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Sample records for stage embryos electronic

  1. Somatic Embryos in Catharanthus roseus: A Scanning Electron Microscopic Study

    Directory of Open Access Journals (Sweden)

    Junaid ASLAM

    2014-06-01

    Full Text Available Catharanthus roseus (L. G. Don is an important medicinal plant as it contains several anti-cancerous compounds, like vinblastine and vincristine. Plant tissue culture technology (organogenesis and embryogenesis has currently been used in fast mass propagating raw materials for secondary metabolite synthesis. In this present communication, scanning electron microscopic (SEM study of somatic embryos was conducted and discussed. The embryogenic callus was first induced from hypocotyls of in vitro germinated seeds on which somatic embryos, differentiated in numbers, particularly on 2,4-D (1.0 mg/L Murashige and Skoog (MS was medium. To understand more about the regeneration method and in vitro formed embryos SEM was performed. The SEM study revealed normal somatic embryo origin and development from globular to heart-, torpedo- and then into cotyledonary-stage of embryos. At early stage, the embryos were clustered together in a callus mass and could not easily be detached from the parental tissue. The embryos were often long cylindrical structure with or without typical notch at the tip. Secondary embryos were also formed on primary embryo structure. The advanced cotyledonary embryos showed prominent roots and shoot axis, which germinated into plantlets. The morphology, structure and other details of somatic embryos at various stages were presented.

  2. Cryopreservation of biopsied cleavage stage human embryos.

    Science.gov (United States)

    Stachecki, James J; Cohen, Jacques; Munné, Santiago

    2005-12-01

    The aim was to develop a method to optimize cryopreservation of biopsied multi-celled human embryos. Human day 3 embryos that were donated to research, along with those found to be chromosomally abnormal after blastomere biopsy and fluorescence in-situ hyridization (FISH), were cryopreserved using a slow-freezing protocol in either standard embryo cryopreservation solution [embryo transfer freezing medium (ETFM), a conventional sodium-based medium] or CJ3 (a choline-based, sodium-free medium). After thawing, the number of intact cells was recorded and the previously biopsied embryos were re-analysed using FISH. Biopsied embryos had a lower proportion of intact blastomeres after cryopreservation as compared with intact embryos. However, a significantly (P < 0.05) higher proportion of blastomeres from intact and biopsied embryos cryopreserved in CJ3 (84.1 and 80.1% respectively) survived after thaw than those in ETFM (73.6 and 50.5% respectively). The proportion of aneuploid and mosaic embryos was not statistically different between the two groups. In addition, the frequency of lost cells by aneuploid and mosaic embryos was similar. This study describes a new method that improves the survival of cryopreserved biopsied embryos, and shows that it may also be beneficial for the storage of intact human multi-celled embryos.

  3. Field emission scanning electron microscopy and transmission electron microscopy studies of the chorion, plasma membrane and syncytial layers of the gastrula-stage embryo of the zebrafish Brachydanio rerio : a consideration of the structural and functional relationships with respect to cryoprotectant penetration

    NARCIS (Netherlands)

    Rawson, DM; Zhang, T; Kalicharan, D; Jongebloed, WL

    The structure of the chorion and plasma membranes of gastrula-stage zebrafish Brachydanio rerio embryos were studied using field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). These studies confirm the outer chorion membrane complex to be 1.5-2.5 mu m in

  4. Somatic Embryos in Catharanthus roseus: A Scanning Electron Microscopic Study

    Directory of Open Access Journals (Sweden)

    Junaid ASLAM

    2014-06-01

    Full Text Available Catharanthus roseus (L. G. Don is an important medicinal plant as it contains several anti-cancerous compounds, like vinblastine and vincristine. Plant tissue culture technology (organogenesis and embryogenesis has currently been used in fast mass propagating raw materials for secondary metabolite synthesis. In this present communication, scanning electron microscopic (SEM study of somatic embryos was conducted and discussed. The embryogenic callus was first induced from hypocotyls of in vitro germinated seeds on which somatic embryos, differentiated in numbers, particularly on 2,4-D (1.0 mg/L Murashige and Skoog (MS was medium. To understand more about the regeneration method and in vitro formed embryos SEM was performed. The SEM study revealed normal somatic embryo origin and development from globular to heart-, torpedo- and then into cotyledonary-stage of embryos. At early stage, the embryos were clustered together in a callus mass and could not easily be detached from the parental tissue. The embryos were often long cylindrical structure with or without typical notch at the tip. Secondary embryos were also formed on primary embryo structure. The advanced cotyledonary embryos showed prominent roots and shoot axis, which germinated into plantlets. The morphology, structure and other details of somatic embryos at various stages were presented.

  5. Extracellular matrix synthesis in blastula and gastrula stages of normal and hybrid frog embryos

    International Nuclear Information System (INIS)

    Johnson, K.E.

    1978-01-01

    Pulse-chase labelling experiments and light- and electron-microscopic autoradiography were used to examine the site of synthesis, mode of transport, and sites of deposition of fucose-, glucose- and mannose-labelled materials in different developmental stages of normal developing Rana pipiens embryos and interspecific hybrid embryos formed by fertilizing the eggs of R. pipiens with the sperm of R. catesbeiana. In both normal and hybrid embryos, after a 15-30 min pulse, grains are closely associated with juxtanuclear and cytoplasmic collections of membrane-bound vescicles which resemble the Golgi apparatus. In normal embryos following a 15-30 min pulse and a 60-min chase, grains are largely cleared from the cytoplasmic vescicles and deposited in the extra-cellular spaces or along cell surfaces. In contrast, arrested hybrid embryos given a 15-30 min pulse and a 60-min chase show a marked accumulation of grains over cytoplasmic structures such as the Golgi apparatus and vescicular elements in the cell cortex. Certain interesting features of regional variation in synthetic activity in developing normal embryos are also described. (author)

  6. Effect of chilling on the development of in vitro produced bovine embryos at various cleavage stages

    OpenAIRE

    Balasubramanian, S.; Rho, Gyu-Jin

    2006-01-01

    Purpose: Bovine embryos and zygotes are known to be sensitive to “temperature shock” when cooled to temperatures near 0°C. The effect of chilling on in vitro derived embryos at various cleavage stages was investigated.

  7. The effect of flurbiprofen on the development of anencephaly in early stage chicken embryos.

    Science.gov (United States)

    Özeren, Ersin; Er, Uygur; Güvenç, Yahya; Demirci, Adnan; Arıkök, Ata Türker; Şenveli, Engin; Ergün, Rüçhan Behzat

    2015-04-01

    The study investigated the effect of flurbiprofen on the development of anencephaly in early stage chicken embryos. We looked at four groups with a total of 36 embryos. There was a control group, a normal saline group, a normal-dose group and a high-dose group with ten, ten, eight and eight eggs with embryo respectively. Two embryos in the control group, studied with light microscopy at 48 h, were consistent with 28-29 hours' incubation in the Hamburger-Hamilton System. They had open neural tubes. The other embryos in this group were considered normal. One embryo in the normal saline group was on the occlusion stage at 48 h. One embryo showed an open neural tube. They were compatible with 28-29 hours' incubation in the Hamburger-Hamilton system. The remaining eight embryos showed normal development. In the normal dose group, one embryo showed underdevelopment of the embryonic disc and the embryo was dead. In four embryos, the neural tubes were open. One cranial malformation was found that was complicated with anencephaly in one embryo. In two embryos the neural tubes were closed, as they showed normal development, and they reached their expected stages according to the Hamburger-Hamilton classification. There was no malformation or growth retardation. Four experimental embryos were anencephalic in the high dose group, and three embryos had open neural tubes. One embryo exhibited both anencephaly and a neural tube closure defect. None of the embryos in this group showed normal development. Even the usual therapeutic doses of flurbiprofen increased the risk of neural tube defect. Flurbiprofen was found to significantly increase the risk of anencephaly. The provision of improved technical materials and studies with larger sample sizes will reveal the stage of morphological disruption during the development of embryos.

  8. The effects of MRI on mouse embryos during fetal stage

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Takashi; Sakazaki, Takahiko; Itokawa, Yuka [Suzuka University of Medical Science, Koriyama (Japan)] (and others)

    2006-06-15

    The effects of Magnetic Resonance Imaging (MRI) on mouse embryos at the early stage of organogenesis were investigated. Pregnant ICR mice were exposed on day 8 of gestation to MRI at 0.5 T for 0.5 hour to 3 hours. The mortality rates of embryos or fetuses, the incidence of external malformations, fetal body weight and sex ratio were observed at day 18 of gestation. A significant increase in embryonic mortality was observed after exposure to either 0.5 T MRI for 0.5 hour or 2 hours. However, the exposure to MRI for 1 hour or 3 hours did not induce any significant increase in embryonic mortality when compared with control. External malformations such as exencephaly, cleft palate and anomalies of tail were observed in all experimental groups exposed to each MRI. A statistically significant increase of external malformations was observed in all groups treated with 0.5 T MRI for 0.5 hour and 3 hours. The incidence of external malformations in the mice group exposed to 0.5 T MRI for 0.5-hour was found to be higher than those of mice group exposed to 0.5 T MRI for 2 hours. The effects of MRI on the external malformations might not to be dose-dependent. There was no statistically significant difference in fetal body weight and sex ratio among each MRI exposure groups.

  9. Cleavage stage versus blastocyst stage embryo transfer in assisted reproductive technology.

    Science.gov (United States)

    Glujovsky, Demián; Farquhar, Cindy; Quinteiro Retamar, Andrea Marta; Alvarez Sedo, Cristian Roberto; Blake, Deborah

    2016-06-30

    Advances in cell culture media have led to a shift in in vitro fertilisation (IVF) practice from cleavage stage embryo transfer to blastocyst stage transfer. The rationale for blastocyst transfer is to improve both uterine and embryonic synchronicity and enable self selection of viable embryos, thus resulting in better live birth rates. To determine whether blastocyst stage (day 5 to 6) embryo transfers improve the live birth rate, and other associated outcomes, compared with cleavage stage (day 2 to 3) embryo transfers. We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library; 2016, Issue 4), MEDLINE, EMBASE, PsycINFO, CINAHL, and Bio extracts from inception to 4th April 2016. We also searched registers of ongoing trials and the reference lists of studies retrieved. We included randomised controlled trials (RCTs) which compared the effectiveness of blastocyst versus cleavage stage transfers. We used standard methodological procedures recommended by Cochrane. Our primary outcomes were live birth and cumulative clinical pregnancy rates. Secondary outcomes were clinical pregnancy, multiple pregnancy, high order pregnancy, miscarriage, failure to transfer embryos, and embryo freezing. We assessed the overall quality of the evidence for the main comparisons using GRADE methods. We included 27 RCTs (4031 couples or women).The live birth rate following fresh transfer was higher in the blastocyst transfer group (odds ratio (OR) 1.48, 95% confidence interval (CI) 1.20 to 1.82; 13 RCTs, 1630 women, I(2) = 45%, low quality evidence) following fresh transfer. This suggests that if 29% of women achieve live birth after fresh cleavage stage transfer, between 32% and 42% would do so after fresh blastocyst stage transfer.There was no evidence of a difference between the groups in rates per couple of cumulative pregnancy following fresh and frozen

  10. Optimal developmental stage for vitrification of parthenogenetically activated porcine embryos

    DEFF Research Database (Denmark)

    Li, Rong; Li, Juan; Kragh, Peter

    2012-01-01

    -lapse monitored for 24 h or analyzed by diffential staining. After warming, the embryos had to be cultured for at least 8 h before their survival rates were stabilized. Both the survival rate and 8 h and the hatching rate at 24 h of Day 4 embryos were significantly higher than those vitrified on Day5 or Day 6 (P...

  11. Improvement of porcine cloning efficiency by trichostain A through early-stage induction of embryo apoptosis.

    Science.gov (United States)

    Ji, Qianqian; Zhu, Kongju; Liu, Zhiguo; Song, Zhenwei; Huang, Yuankai; Zhao, Haijing; Chen, Yaosheng; He, Zuyong; Mo, Delin; Cong, Peiqing

    2013-03-15

    Trichostain A (TSA), an inhibitor of histone deacetylases, improved developmental competence of SCNT embryos in many species, apparently by improved epigenetic reprogramming. The objective of the present study was to determine the effects of TSA-induced apoptosis in cloned porcine embryos. At various developmental stages, a comet assay and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling staining were used to detect apoptosis, and real-time polymerase chain reaction was used to assess expression of genes related to apoptosis and pluripotency. In this study, TSA significantly induced apoptosis (in a dose-dependent manner) at the one-, two-, and four-cell stages. However, in blastocyst stage embryos, TSA decreased the apoptotic index (P < 0.05). Expression levels of Caspase 3 were higher in TSA-treated versus control embryos at the two-cell stage (not statistically significant). The expression ratio of antiapoptotic Bcl-xl gene to proapoptotic Bax gene, an indicator of antiapoptotic potential, was higher in TSA-treated groups at the one-, two-, and four-cell and blastocyst stages. Furthermore, expression levels of pluripotency-related genes, namely, Oct4 and Nanog, were elevated at the morula stage (P < 0.05) in TSA treatment groups. We concluded that inducing apoptosis might be a mechanism by which TSA promotes development of reconstructed embryos. At the initial stage of apoptosis induction, abnormal cells were removed, thereby enhancing proliferation of healthy cells and improving embryo quality. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. The Early Stages of Heart Development: Insights from Chicken Embryos

    Directory of Open Access Journals (Sweden)

    Johannes G. Wittig

    2016-04-01

    Full Text Available The heart is the first functioning organ in the developing embryo and a detailed understanding of the molecular and cellular mechanisms involved in its formation provides insights into congenital malformations affecting its function and therefore the survival of the organism. Because many developmental mechanisms are highly conserved, it is possible to extrapolate from observations made in invertebrate and vertebrate model organisms to humans. This review will highlight the contributions made through studying heart development in avian embryos, particularly the chicken. The major advantage of chick embryos is their accessibility for surgical manipulation and functional interference approaches, both gain- and loss-of-function. In addition to experiments performed in ovo, the dissection of tissues for ex vivo culture, genomic, or biochemical approaches is straightforward. Furthermore, embryos can be cultured for time-lapse imaging, which enables tracking of fluorescently labeled cells and detailed analysis of tissue morphogenesis. Owing to these features, investigations in chick embryos have led to important discoveries, often complementing genetic studies in mice and zebrafish. As well as including some historical aspects, we cover here some of the crucial advances made in understanding early heart development using the chicken model.

  13. Stage selection and restricted oviposition period improves cryopreservation of dipteran embryos.

    Science.gov (United States)

    Rajamohan, Arun; Rinehart, Joseph P; Leopold, Roger A

    2015-04-01

    Embryos of two dipteran species (Musca domestica and Lucilia sericata) were assessed for an effective sampling time that would result in the highest post-cryopreservation hatch rate, with a primary goal to define species-specific egg collection periods and the effects of manual stage selection on post cryopreservation yield. The effects of the time taken to collect eggs on, (a) the proportion of embryos reaching a specific developmental stage between 17 and 20 h of development, and (b) the post-cryopreservation hatch rate were assessed. Permeabilization treatment applied at any stage of embryonic development did not significantly reduce embryo viability. Eggs collected over longer durations significantly reduced the number of embryos available in a specific developmental stage amenable to cryopreservation. Hatch percentage after cryopreservation of the embryos of M. domestica collected over a 60 min period was 10.7 ± 8.7% compared to 31 ± 5% for the eggs collected for just 15 min. Similarly, percent hatch in L. sericata resulted in 17.0 ± 3.9 and cryopreservation after manual selection of specific embryonic developmental stages from the dechorionated samples. Post-cryopreservation hatching rate for stage-selected M. domestica embryos was 86.5 ± 5.5% compared to 33.3 ± 4.5% for embryos staged only by an overall visual confirmation. In the case of L. sericata, the hatching percentage was 79.0 ± 11.1 for stage-selected embryos compared to 17.0 ± 3.9% without individual selection. Published by Elsevier Inc.

  14. Strain preservation of experimental animals: vitrification of two-cell stage embryos for multiple mouse strains.

    Science.gov (United States)

    Eto, Tomoo; Takahashi, Riichi; Kamisako, Tsutomu

    2015-04-01

    Strain preservation of experimental animals is crucial for experimental reproducibility. Maintaining complete animal strains, however, is costly and there is a risk for genetic mutations as well as complete loss due to disasters or illness. Therefore, the development of effective vitrification techniques for cryopreservation of multiple experimental animal strains is important. We examined whether a vitrification method using cryoprotectant solutions, P10 and PEPeS, is suitable for preservation of multiple inbred and outbred mouse strains. First, we investigated whether our vitrification method using cryoprotectant solutions was suitable for two-cell stage mouse embryos. In vitro development of embryos exposed to the cryoprotectant solutions was similar to that of fresh controls. Further, the survival rate of the vitrified embryos was extremely high (98.1%). Next, we collected and vitrified two-cell stage embryos of 14 mouse strains. The average number of embryos obtained from one female was 7.3-33.3. The survival rate of vitrified embryos ranged from 92.8% to 99.1%, with no significant differences among mouse strains. In vivo development did not differ significantly between fresh controls and vitrified embryos of each strain. For strain preservation using cryopreserved embryos, two offspring for inbred lines and one offspring for outbred lines must be produced from two-cell stage embryos collected from one female. The expected number of surviving fetuses obtained from embryos collected from one female of either the inbred or outbred strains ranged from 2.9 to 19.5. The findings of the present study indicated that this vitrification method is suitable for strain preservation of multiple mouse strains. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Monozygotic Triplets and Dizygotic Twins following Transfer of Three Poor-Quality Cleavage Stage Embryos

    Directory of Open Access Journals (Sweden)

    Reshef Tal

    2012-01-01

    Full Text Available Background. Assisted reproductive technology has been linked to the increased incidence of monozygotic twinning. It is of clinical importance due to the increased risk of complications in multiple pregnancies in general and in monozygotic twins in particular. Case. A 29-year-old female, nulligravida underwent her first IVF cycle. Three poor-quality cleavage stage embryos were transferred resulting in monochorionic triamniotic triplets and dichorionic diamniotic twins. Selective embryo reduction was performed at 12 weeks leaving dichorionic twins. The patient underwent emergency cesarean section due to preterm labor and nonreassuring fetal heart tracing at 30 weeks of gestation. Conclusion. Our case emphasizes that even embryos with significant morphological abnormalities should be considered viable and the possibility of simultaneous spontaneous embryo splitting must be factored into determining number of embryos to transfer.

  16. Pentachlorophenol exposure causes Warburg-like effects in zebrafish embryos at gastrulation stage

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Ting; Zhao, Jing [Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Technology, Tongji University, Shanghai 200092 (China); Hu, Ping [Key Laboratory of Model Animal for Disease Study, Ministry of Education, Model Animal Research Center, Nanjing University, Nanjing 210061 (China); State Key Laboratory of Reproductive Medicine, Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing 210029 (China); Dong, Zhangji; Li, Jingyun [Key Laboratory of Model Animal for Disease Study, Ministry of Education, Model Animal Research Center, Nanjing University, Nanjing 210061 (China); Zhang, Hongchang [Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Technology, Tongji University, Shanghai 200092 (China); Yin, Daqiang, E-mail: yindq@tongji.edu.cn [Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Technology, Tongji University, Shanghai 200092 (China); Zhao, Qingshun, E-mail: qingshun@nju.edu.cn [Key Laboratory of Model Animal for Disease Study, Ministry of Education, Model Animal Research Center, Nanjing University, Nanjing 210061 (China)

    2014-06-01

    Pentachlorophenol (PCP) is a prevalent pollutant in the environment and has been demonstrated to be a serious toxicant to humans and animals. However, little is known regarding the molecular mechanism underlying its toxic effects on vertebrate early development. To explore the impacts and underlying mechanisms of PCP on early development, zebrafish (Danio rerio) embryos were exposed to PCP at concentrations of 0, 20 and 50 μg/L, and microscopic observation and cDNA microarray analysis were subsequently conducted at gastrulation stage. The morphological observations revealed that PCP caused a developmental delay of zebrafish embryos in a concentration-dependent manner. Transcriptomic data showed that 50 μg/L PCP treatment resulted in significant changes in gene expression level, and the genes involved in energy metabolism and cell behavior were identified based on gene functional enrichment analysis. The energy production of embryos was influenced by PCP via the activation of glycolysis along with the inhibition of oxidative phosphorylation (OXPHOS). The results suggested that PCP acts as an inhibitor of OXPHOS at 8 hpf (hours postfertilization). Consistent with the activated glycolysis, the cell cycle activity of PCP-treated embryos was higher than the controls. These characteristics are similar to the Warburg effect, which occurs in human tumors. The microinjection of exogenous ATP confirmed that an additional energy supply could rescue PCP-treated embryos from the developmental delay due to the energy deficit. Taken together, our results demonstrated that PCP causes a Warburg-like effect on zebrafish embryos during gastrulation, and the affected embryos had the phenotype of developmental delay. - Highlights: • We treat zebrafish embryos with PCP at gastrula stage. • PCP acts as an oxidative phosphorylation inhibitor, not an uncoupler, in gastrulation. • Exogenous ATP injection will rescue the development of effected embryos. • The transcriptome of PCP

  17. Pentachlorophenol exposure causes Warburg-like effects in zebrafish embryos at gastrulation stage

    International Nuclear Information System (INIS)

    Xu, Ting; Zhao, Jing; Hu, Ping; Dong, Zhangji; Li, Jingyun; Zhang, Hongchang; Yin, Daqiang; Zhao, Qingshun

    2014-01-01

    Pentachlorophenol (PCP) is a prevalent pollutant in the environment and has been demonstrated to be a serious toxicant to humans and animals. However, little is known regarding the molecular mechanism underlying its toxic effects on vertebrate early development. To explore the impacts and underlying mechanisms of PCP on early development, zebrafish (Danio rerio) embryos were exposed to PCP at concentrations of 0, 20 and 50 μg/L, and microscopic observation and cDNA microarray analysis were subsequently conducted at gastrulation stage. The morphological observations revealed that PCP caused a developmental delay of zebrafish embryos in a concentration-dependent manner. Transcriptomic data showed that 50 μg/L PCP treatment resulted in significant changes in gene expression level, and the genes involved in energy metabolism and cell behavior were identified based on gene functional enrichment analysis. The energy production of embryos was influenced by PCP via the activation of glycolysis along with the inhibition of oxidative phosphorylation (OXPHOS). The results suggested that PCP acts as an inhibitor of OXPHOS at 8 hpf (hours postfertilization). Consistent with the activated glycolysis, the cell cycle activity of PCP-treated embryos was higher than the controls. These characteristics are similar to the Warburg effect, which occurs in human tumors. The microinjection of exogenous ATP confirmed that an additional energy supply could rescue PCP-treated embryos from the developmental delay due to the energy deficit. Taken together, our results demonstrated that PCP causes a Warburg-like effect on zebrafish embryos during gastrulation, and the affected embryos had the phenotype of developmental delay. - Highlights: • We treat zebrafish embryos with PCP at gastrula stage. • PCP acts as an oxidative phosphorylation inhibitor, not an uncoupler, in gastrulation. • Exogenous ATP injection will rescue the development of effected embryos. • The transcriptome of PCP

  18. Biopsy of human morula-stage embryos: outcome of 215 IVF/ICSI cycles with PGS.

    Directory of Open Access Journals (Sweden)

    Elena E Zakharova

    Full Text Available Preimplantation genetic diagnosis (PGD is commonly performed on biopsies from 6-8-cell-stage embryos or blastocyst trophectoderm obtained on day 3 or 5, respectively. Day 4 human embryos at the morula stage were successfully biopsied. Biopsy was performed on 709 morulae from 215 ICSI cycles with preimplantation genetic screening (PGS, and 3-7 cells were obtained from each embryo. The most common vital aneuploidies (chromosomes X/Y, 21 were screened by fluorescence in situ hybridization (FISH. No aneuploidy was observed in 72.7% of embryos, 91% of those developed to blastocysts. Embryos were transferred on days 5-6. Clinical pregnancy was obtained in 32.8% of cases, and 60 babies were born. Patients who underwent ICSI/PGS treatment were compared with those who underwent standard ICSI treatment by examining the percentage of blastocysts, pregnancy rate, gestational length, birth height and weight. No significant differences in these parameters were observed between the groups. Day 4 biopsy procedure does not adversely affect embryo development in vitro or in vivo. The increased number of cells obtained by biopsy of morulae might facilitate diagnostic screening. There is enough time after biopsy to obtain PGD results for embryo transfer on day 5-6 in the current IVF cycle.

  19. Cold-induced imbibition damage of lettuce embryos: A study using cryo-scanning electron microscopy

    NARCIS (Netherlands)

    Nijsse, J.; Walther, P.; Hoekstra, F.

    2004-01-01

    The impact of rehydration on a multicellular organism was studied in lettuce (Lactuca sativa L.) embryos, using cryo-scanning electron microscopy (cryo-SEM). Naked embryos were sensitive to imbibitional stress, whereas embryos with an intact, thick-walled endosperm were not. Imbibitional injury to

  20. Temporal and developmental-stage variation in the occurrence of mitotic errors in tripronuclear human preimplantation embryos

    NARCIS (Netherlands)

    Mantikou, Eleni; van Echten-Arends, Jannie; Sikkema-Raddatz, Birgit; van der Veen, Fulco; Repping, Sjoerd; Mastenbroek, Sebastiaan

    2013-01-01

    Mitotic errors during early development of human preimplantation embryos are common, rendering a large proportion of embryos chromosomally mosaic. It is also known that the percentage of diploid cells in human diploid-aneuploid mosaic embryos is higher at the blastocyst than at the cleavage stage.

  1. Temporal and Developmental-Stage Variation in the Occurrence of Mitotic Errors in Tripronuclear Human Preimplantation Embryos

    NARCIS (Netherlands)

    Mantikou, Eleni; van Echten-Arends, Jannie; Sikkema-Raddatz, Birgit; van der Veen, Fulco; Repping, Sjoerd; Mastenbroek, Sebastiaan

    Mitotic errors during early development of human preimplantation embryos are common, rendering a large proportion of embryos chromosomally mosaic. It is also known that the percentage of diploid cells in human diploid-aneuploid mosaic embryos is higher at the blastocyst than at the cleavage stage.

  2. Chromosome fragility at FRAXA in human cleavage stage embryos at risk for fragile X syndrome.

    Science.gov (United States)

    Verdyck, Pieter; Berckmoes, Veerle; De Vos, Anick; Verpoest, Willem; Liebaers, Inge; Bonduelle, Maryse; De Rycke, Martine

    2015-10-01

    Fragile X syndrome (FXS), the most common inherited intellectual disability syndrome, is caused by expansion and hypermethylation of the CGG repeat in the 5' UTR of the FMR1 gene. This expanded repeat, also known as the rare fragile site FRAXA, causes X chromosome fragility in cultured cells from patients but only when induced by perturbing pyrimidine synthesis. We performed preimplantation genetic diagnosis (PGD) on 595 blastomeres biopsied from 442 cleavage stage embryos at risk for FXS using short tandem repeat (STR) markers. In six blastomeres, from five embryos an incomplete haplotype was observed with loss of all alleles telomeric to the CGG repeat. In all five embryos, the incomplete haplotype corresponded to the haplotype carrying the CGG repeat expansion. Subsequent analysis of additional blastomeres from three embryos by array comparative genomic hybridization (aCGH) confirmed the presence of a terminal deletion with a breakpoint close to the CGG repeat in two blastomeres from one embryo. A blastomere from another embryo showed the complementary duplication. We conclude that a CGG repeat expansion at FRAXA causes X chromosome fragility in early human IVF embryos at risk for FXS. © 2015 Wiley Periodicals, Inc.

  3. Stage-dependent toxicity of bisphenol a on Rhinella arenarum (anura, bufonidae) embryos and larvae.

    Science.gov (United States)

    Wolkowicz, Ianina R Hutler; Herkovits, Jorge; Pérez Coll, Cristina S

    2014-02-01

    The acute and chronic toxicity of bisphenol A (BPA) was evaluated on the common South American toad Rhinella arenarum embryos and larvae by means of continuous and pulse exposure treatments. Embryos were treated continuously from early blastula (S.4) up to complete operculum (S.25), during early larval stages and by means of 24 h pulse exposures of BPA in concentrations ranging between 1.25 and 40 mg L(-1) , in order to evaluate the susceptibility to this compound in different developmental stages. For lethal effects, S.25 was the most sensitive and gastrula was the most resistant to BPA. The Teratogenic Index for neurula, the most sensitive embryonic stage for sublethal effects was 4.7. The main morphological alterations during early stages were: delayed or arrested development, reduced body size, persistent yolk plug, microcephaly, axial/tail flexures, edemas, blisters, waving fin, underdeveloped gills, mouth malformations, and cellular dissociation. BPA caused a remarkable narcotic effect from gill circulation stage (S.20) onwards in all the organisms exposed after 3 h of treatment with 10 mg L(-1) BPA. After recovering, the embryos exhibited scarce response to stimuli, erratic or circular swimming, and spasmodic contractions from 5 mg L(-1) onwards. Our results highlight the lethal and sublethal effectsof BPA on R. arenarum embryos and larvae, in the last case both at structural and functional levels. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

  4. Nuclear and cellular expression data from the whole 16-cell stage Arabidopsis thaliana embryo and a cell type-specific expression atlas of the early Arabidopsis embryo

    NARCIS (Netherlands)

    Palovaara, J.P.J.

    2017-01-01

    SuperSeries contain expression data from the nuclei of cell types involved in patterning events, with focus on root apical stem cell formation, at 16-cell stage, early globular stage and late globular stage in the early Arabidopsis embryo (atlas). Expression data comparing nuclear and cellular RNA

  5. Nerve growth factor regulates axial rotation during early stages of chick embryo development

    Science.gov (United States)

    Manca, Annalisa; Capsoni, Simona; Di Luzio, Anna; Vignone, Domenico; Malerba, Francesca; Paoletti, Francesca; Brandi, Rossella; Arisi, Ivan; Cattaneo, Antonino; Levi-Montalcini, Rita

    2012-01-01

    Nerve growth factor (NGF) was discovered because of its neurotrophic actions on sympathetic and sensory neurons in the developing chicken embryo. NGF was subsequently found to influence and regulate the function of many neuronal and non neuronal cells in adult organisms. Little is known, however, about the possible actions of NGF during early embryonic stages. However, mRNAs encoding for NGF and its receptors TrkA and p75NTR are expressed at very early stages of avian embryo development, before the nervous system is formed. The question, therefore, arises as to what might be the functions of NGF in early chicken embryo development, before its well-established actions on the developing sympathetic and sensory neurons. To investigate possible roles of NGF in the earliest stages of development, stage HH 11–12 chicken embryos were injected with an anti-NGF antibody (mAb αD11) that binds mature NGF with high affinity. Treatment with anti-NGF, but not with a control antibody, led to a dose-dependent inversion of the direction of axial rotation. This effect of altered rotation after anti NGF injection was associated with an increased cell death in somites. Concurrently, a microarray mRNA expression analysis revealed that NGF neutralization affects the expression of genes linked to the regulation of development or cell proliferation. These results reveal a role for NGF in early chicken embryo development and, in particular, in the regulation of somite survival and axial rotation, a crucial developmental process linked to left–right asymmetry specification. PMID:22308471

  6. Syntheses of nucleic acid and protein in somatic embryos of Fritillaria ussuriensis maxim in different development stages

    International Nuclear Information System (INIS)

    Wang Shuyu; Tang Wei; Wang Hui

    1993-09-01

    After developing a procedure for somatic embryogenesis in Fritillaria ussuriensis, dynamics on the syntheses of DNA, RNA, and protein during globular, heart-shaped, torpedo-shaped, cotyledonary, and mature somatic embryo stages was demonstrated by both autoradiography and scintillation counting. The rates of syntheses of DNA, RNA, and protein gradually increase between the globular and cotyledonary somatic embryos stages. DNA, RNA, and protein synthesis rates are in peak at the cotyledonary later stage, precotyledonary stage, and cotyledonary stage, respectively. It appears that more DNA, RNA, and protein are synthesized in the cotyledonary somatic embryo stage than in other stages. All these results indicate that an increased syntheses of DNA, RNA, and protein is associated with the differentiation of embryogenic cells and organogenesis in somatic embryos

  7. Volatiles identified from five stages of embryo development separated from a heterogeneous suspension culture of Daucus carota.

    Science.gov (United States)

    Kennedy, A H; Chamberlain, D; Wilson, G; Ryan, M F

    1991-11-01

    Five stages of embryo development were fractionated from a mature culture of Daucus carota (Gelbe Rheinsche), using a series of metal sieves. The composition of the population of embryos in each fraction was determined quantitatively from microscopic investigations. Volatiles from samples of tissue from six stages of development were trapped on activated charcoal cartridges. These volatiles, some of which may play a significant role in the interaction of the plant with the carrot root fly (Psila rosae), were analysed using gas chromatography/mass spectroscopy. The resulting chromatograms are arranged in order of embryo development. The progressive elaboration of the volatile profile reflects the increased biosynthetic capacity of the developing embryo.

  8. Incorporation of 3H-thymidine during early developmental stages of ovoviviparous and oviparous embryos in the brine

    International Nuclear Information System (INIS)

    Iwasaki, Tamiko

    1980-01-01

    DNA synthesis in the embryos during various developmental stages in the brood pouch of the Artemia female as well as the encysted eggs produced by oviparity was studied by autoradiography using 3 H-thymidine. Nuclei of the embryos through the blastula stage in the brood pouch were labelled, regardless of the existence of the thick shell surrounding the embryos. However, incorporation of 3 H-thymidine into nuclei was absent in the stages between gastrula and early nauplii which had developed in the brood pouch or were delivered from encysted dry eggs. (author)

  9. Initial stages of calcium uptake and mineral deposition in sea urchin embryos

    OpenAIRE

    Vidavsky, Netta; Addadi, Sefi; Mahamid, Julia; Shimoni, Eyal; Ben-Ezra, David; Shpigel, Muki; Weiner, Steve; Addadi, Lia

    2013-01-01

    With the onset of gastrulation, sea urchin embryos deposit a calcium carbonate endoskeleton consisting of two spicules. Sea water is the source for the mineral ions, but the specific stages of the transport and deposition pathway are not well understood. This study shows that the first-formed mineral is deposited inside intracellular micrometer-size vesicles as solid nanospheres. Surprisingly, the initial deposits are distributed widely inside the embryonic cells, including epithelial cells. ...

  10. Genome stability of bovine in vivo-conceived cleavage-stage embryos is higher compared to in vitro-produced embryos.

    Science.gov (United States)

    Tšuiko, Olga; Catteeuw, Maaike; Zamani Esteki, Masoud; Destouni, Aspasia; Bogado Pascottini, Osvaldo; Besenfelder, Urban; Havlicek, Vitezslav; Smits, Katrien; Kurg, Ants; Salumets, Andres; D'Hooghe, Thomas; Voet, Thierry; Van Soom, Ann; Robert Vermeesch, Joris

    2017-11-01

    Is the rate and nature of chromosome instability (CIN) similar between bovine in vivo-derived and in vitro-cultured cleavage-stage embryos? There is a major difference regarding chromosome stability of in vivo-derived and in vitro-cultured embryos, as CIN is significantly lower in in vivo-derived cleavage-stage embryos compared to in vitro-cultured embryos. CIN is common during in vitro embryogenesis and is associated with early embryonic loss in humans, but the stability of in vivo-conceived cleavage-stage embryos remains largely unknown. Because human in vivo preimplantation embryos are not accessible, bovine (Bos taurus) embryos were used to study CIN in vivo. Five young, healthy, cycling Holstein Friesian heifers were used to analyze single blastomeres of in vivo embryos, in vitro embryos produced by ovum pick up with ovarian stimulation (OPU-IVF), and in vitro embryos produced from in vitro matured oocytes retrieved without ovarian stimulation (IVM-IVF). Single blastomeres were isolated from embryos, whole-genome amplified and hybridized on Illumina BovineHD BeadChip arrays together with the bulk DNA from the donor cows (mothers) and the bull (father). DNA was also obtained from the parents of the bull and from the parents of the cows (paternal and maternal grandparents, respectively). Subsequently, genome-wide haplotyping and copy-number profiling was applied to investigate the genomic architecture of 171 single bovine blastomeres of 16 in vivo, 13 OPU-IVF and 13 IVM-IVF embryos. The genomic stability of single blastomeres in both of the in vitro-cultured embryo cohorts was severely compromised (P vivo. Only 18.8% of in vivo-derived embryos contained at least one blastomere with chromosomal anomalies, compared to 69.2% of OPU-IVF embryos (P vivo-developed embryos, in vitro procedures exacerbate chromosomal abnormalities during early embryo development. Hence, the present study highlights that IVF treatment compromises embryo viability and should be applied

  11. Molecular asymmetry in the 8-cell stage Xenopus tropicalis embryo described by single blastomere transcript sequencing.

    Science.gov (United States)

    De Domenico, Elena; Owens, Nick D L; Grant, Ian M; Gomes-Faria, Rosa; Gilchrist, Michael J

    2015-12-15

    Correct development of the vertebrate body plan requires the early definition of two asymmetric, perpendicular axes. The first axis is established during oocyte maturation, and the second is established by symmetry breaking shortly after fertilization. The physical processes generating the second asymmetric, or dorsal-ventral, axis are well understood, but the specific molecular determinants, presumed to be maternal gene products, are poorly characterized. Whilst enrichment of maternal mRNAs at the animal and vegetal poles in both the oocyte and the early embryo has been studied, little is known about the distribution of maternal mRNAs along either the dorsal-ventral or left-right axes during the early cleavage stages. Here we report an unbiased analysis of the distribution of maternal mRNA on all axes of the Xenopus tropicalis 8-cell stage embryo, based on sequencing of single blastomeres whose positions within the embryo are known. Analysis of pooled data from complete sets of blastomeres from four embryos has identified 908 mRNAs enriched in either the animal or vegetal blastomeres, of which 793 are not previously reported as enriched. In contrast, we find no evidence for asymmetric distribution along either the dorsal-ventral or left-right axes. We confirm that animal pole enrichment is on average distinctly lower than vegetal pole enrichment, and that considerable variation is found between reported enrichment levels in different studies. We use publicly available data to show that there is a significant association between genes with human disease annotation and enrichment at the animal pole. Mutations in the human ortholog of the most animally enriched novel gene, Slc35d1, are causative for Schneckenbecken dysplasia, and we show that a similar phenotype is produced by depletion of the orthologous protein in Xenopus embryos. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Body movements during early stages of chick embryo under intermittent low oxygen environment

    Science.gov (United States)

    Moriya, Kenji; Chiba, Yuya; Shimouchi, Akito

    2017-07-01

    We have attempted to elucidate the characteristic pattern of body movements in early stages of chick embryos under intermittent low oxygen incubation environment. In order to achieve this aim, the oxygen control system that can be set arbitrary oxygen concentration was developed. We choose the 18% of O2 concentration and tried to measure the embryonic body movements. As a results, only one chick embryo in the early stages under intermittent 18% O2 environment (the cycle is 18%O2-10min and 21%O2-50min) was successfully recorded and its body movements were analyzed. The characteristic body movements, which are attributed to the instantaneous effect of low oxygen environment, compared with before and after normal O2 condition were not observed. Because the early stage embryos in which the significant organs aside from heart are not formed yet have a strong adaptation to environment changes, short hypoxic condition like a 10 min might not affect instantaneous embryonic physiological changes. Meanwhile, although the cyclic interval of the large body movements becomes short in the normal development, it became long in 18%O2 condition. This result might indicate that intermittent low oxygen condition accumulatively influenced physiological function. Further improvements of accuracy in the oxygen control system and the calculation system of body movements, and further experiments under low oxygen conditions are required in the next step.

  13. Embryo splitting

    Directory of Open Access Journals (Sweden)

    Karl Illmensee

    2010-04-01

    Full Text Available Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board approval has been carried out to determine its efficiency for blastocyst development. Embryo splitting at the 6–8 cell stage provided a much higher developmental efficiency compared to splitting at the 2–5 cell stage. Embryo splitting may be advantageous for providing additional embryos to be cryopreserved and for patients with low response to hormonal stimulation in assisted reproduction programs. Social and ethical issues concerning embryo splitting are included regarding ethics committee guidelines. Prognostic perspectives are presented for human embryo splitting in reproductive medicine.

  14. AFSC/RACE/SAP/Foy: Effects of ocean acidification on embryo stages of Tanner crab: Kodiak Island, Alaska.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To study the effects of ocean acidification we examined the effects of ocean acidification on the embryo stages of the economically important southern Tanner crab,...

  15. Totipotency segregates between the sister blastomeres of two-cell stage mouse embryos.

    Science.gov (United States)

    Casser, E; Israel, S; Witten, A; Schulte, K; Schlatt, S; Nordhoff, V; Boiani, M

    2017-08-15

    Following fertilization in mammals, it is generally accepted that totipotent cells are exclusive to the zygote and to each of the two blastomeres originating from the first mitotic division. This model of totipotency was inferred from a minority of cases in which blastomeres produced monozygotic twins in mice. Was this due to experimental limitation or biological constraint? Here we removed experimental obstacles and achieved reliable quantification of the prevalence of dual totipotency among mouse two-cell stage blastomeres. We separated the blastomeres of 1,252 two-cell embryos, preserving 1,210 of the pairs. Two classes of monozygotic twins became apparent at the blastocyst stage: 27% formed a functional epiblast in both members (concordant), and 73% did so in only one member of the pair (discordant) - a partition that proved insensitive to oocyte quality, sperm-entry point, culture environment and pattern of cleavage. In intact two-cell embryos, the ability of sister blastomeres to generate epiblast was also skewed. Class discovery clustering of the individual blastomeres' and blastocysts' transcriptomes points to an innate origin of concordance and discordance rather than developmental acquisition. Our data place constraints on the commonly accepted idea that totipotency is allocated equally between the two-cell stage blastomeres in mice.

  16. Stage-dependent ethoxyresorufin-O-deethylase (EROD) in vivo activity in medaka (Oryzias latipes) embryos.

    Science.gov (United States)

    González-Doncel, Miguel; Carbonell, Gregoria; San Segundo, Laura; Sastre, Salvador; Beltrán, Eulalia M; Fernández-Torija, Carlos

    2015-09-01

    Using medaka (Oryzias latipes) embryos, this study aimed to quantitatively characterize the stage-dependent in vivo ethoxyresorufin-O-deethylase (EROD) as indicator of cytochrome P4501A (CYP1A) activity. Embryos were challenged for 24-h to an agonist (β-naphthoflavone [BNF], 2.5, 5, 10, and 20 μg L(-1)) or to its combination (2.5 μg L(-1)) with an antagonist (α-naphthoflavone [ANF], 25, 50, 100, and 200 μg L(-1)), initiated at four different developmental time points (1, 3, 6, and 9 d post-fertilization [dpf]). Respective induction and competitive inhibition were evaluated over fluorescent images of whole embryo (nonorgan-specific [NOS] EROD activity) and gallbladder (organ-specific [OS] EROD activity). Both flavonoids showed signs of stability in solution. Generally speaking, the mean fluorescence intensity (MFI) values for NOS EROD increased with BNF concentration and exposure challenge. BNF co-exposure with ⩾50 μg ANF L(-1) during the 1-2 and 3-4 dpf challenges lowered NOS EROD to undetectably induced levels. Significant increments in MFIs for OS-EROD were seen from exposures to ⩾2.5 μg BNF L(-1), peaking during the 6-7 dpf challenge regardless of BNF concentration. The simultaneous BNF/ANF incubation showed competitive inhibition for OS EROD activity, although levels were generally detectably induced during all challenges and at all ANF concentrations. The morphometric in vivo gallbladder analysis indicated significant dilation in the 10 dpf-old embryos co-exposed to BNF and 200 μg ANF L(-1). This quantitative approach can be used successfully at 4 dpf at the NOS-EROD or OS-EROD levels, although the NOS-EROD response was sensitive enough to induction or inhibition, even at 2 dpf. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Zinc deficiency in the 11 day rat embryo: a scanning and transmission electron microscope study

    Energy Technology Data Exchange (ETDEWEB)

    Harding, A.J.; Dreosti, I.E.; Tulsi, R.S.

    1988-01-01

    Zinc deficient rat embryos were obtained on the 11th day of pregnancy and examined by scanning and transmission electron microscopy. Scanning electron microscopy revealed an increase in the number of deformed embryos, as well as embryonic growth retardation. In addition, the epithelium of zinc deficient embryos displayed a marked increase in surface microvilli, as well as the presence of blebbing. Transmission electron microscopy indicated extensive cell death in the neural epithelium which was apparently more severely damaged by zinc deficiency than were mesenchymal cells. Mitochondrial cristae were affected to a greater degree than any other membrane of the cell and cristael disintegration appeared to represent the principal cellular lesion preceding necrosis of neural cells and neural tube teratology. 29 references, 4 figures, 1 table.

  18. Prediction of in-vitro developmental competence of early cleavage-stage mouse embryos with compact time-lapse equipment.

    Science.gov (United States)

    Pribenszky, Csaba; Losonczi, Eszter; Molnár, Miklós; Lang, Zsolt; Mátyás, Szabolcs; Rajczy, Klára; Molnár, Katalin; Kovács, Péter; Nagy, Péter; Conceicao, Jason; Vajta, Gábor

    2010-03-01

    Single blastocyst transfer is regarded as an efficient way to achieve high pregnancy rates and to avoid multiple pregnancies. Risk of cancellation of transfer due to a lack of available embryos may be reduced by early prediction of blastocyst development. Time-lapse investigation of mouse embryos shows that the time of the first and second cleavage (to the 2- and 3-cell stages, respectively) has a strong predictive value for further development in vitro, while cleavage from the 3-cell to the 4-cell stage has no predictive value. In humans, embryo fragmentation during preimplantation development has been associated with lower pregnancy rates and a higher incidence of developmental abnormalities. Analysis of time-lapse records shows that most fragmentation is reversible in the mouse and is resorbed in an average of 9 h. Daily or bi-daily microscopic checks of embryo development, applied routinely in human IVF laboratories, would fail to detect 36 or 72% of these fragmentations, respectively. Fragmentation occurring in a defined time frame has a strong predictive value for in-vitro embryo development. The practical compact system used in the present trial, based on the 'one camera per patient' principle, has eliminated the usual disadvantages of time-lapse investigations and is applicable for the routine follow-up of in-vitro embryo development. Copyright 2009 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Initial stages of calcium uptake and mineral deposition in sea urchin embryos.

    Science.gov (United States)

    Vidavsky, Netta; Addadi, Sefi; Mahamid, Julia; Shimoni, Eyal; Ben-Ezra, David; Shpigel, Muki; Weiner, Steve; Addadi, Lia

    2014-01-07

    Sea urchin larvae have an endoskeleton consisting of two calcitic spicules. We reconstructed various stages of the formation pathway of calcium carbonate from calcium ions in sea water to mineral deposition and integration into the forming spicules. Monitoring calcium uptake with the fluorescent dye calcein shows that calcium ions first penetrate the embryo and later are deposited intracellularly. Surprisingly, calcium carbonate deposits are distributed widely all over the embryo, including in the primary mesenchyme cells and in the surface epithelial cells. Using cryo-SEM, we show that the intracellular calcium carbonate deposits are contained in vesicles of diameter 0.5-1.5 μm. Using the newly developed airSEM, which allows direct correlation between fluorescence and energy dispersive spectroscopy, we confirmed the presence of solid calcium carbonate in the vesicles. This mineral phase appears as aggregates of 20-30-nm nanospheres, consistent with amorphous calcium carbonate. The aggregates finally are introduced into the spicule compartment, where they integrate into the growing spicule.

  20. Initial stages of calcium uptake and mineral deposition in sea urchin embryos

    Science.gov (United States)

    Vidavsky, Netta; Addadi, Sefi; Mahamid, Julia; Shimoni, Eyal; Ben-Ezra, David; Shpigel, Muki; Weiner, Steve; Addadi, Lia

    2014-01-01

    Sea urchin larvae have an endoskeleton consisting of two calcitic spicules. We reconstructed various stages of the formation pathway of calcium carbonate from calcium ions in sea water to mineral deposition and integration into the forming spicules. Monitoring calcium uptake with the fluorescent dye calcein shows that calcium ions first penetrate the embryo and later are deposited intracellularly. Surprisingly, calcium carbonate deposits are distributed widely all over the embryo, including in the primary mesenchyme cells and in the surface epithelial cells. Using cryo-SEM, we show that the intracellular calcium carbonate deposits are contained in vesicles of diameter 0.5–1.5 μm. Using the newly developed airSEM, which allows direct correlation between fluorescence and energy dispersive spectroscopy, we confirmed the presence of solid calcium carbonate in the vesicles. This mineral phase appears as aggregates of 20–30-nm nanospheres, consistent with amorphous calcium carbonate. The aggregates finally are introduced into the spicule compartment, where they integrate into the growing spicule. PMID:24344263

  1. Influence of recipient cytoplasm cell stage on transcription in bovine nucleus transfer embryos

    DEFF Research Database (Denmark)

    Smith, S. D.; Soloy, E.; Kanka, J.

    1996-01-01

    Nucleus transfer for the production of multiple embryos derived from a donor embryo relies upon the reprogramming of the donor nucleus so that it behaves similar to a zygotic nucleus. One indication of nucleus reprogramming is the RNA synthetic activity. In normal bovine embryogenesis, the embryo...

  2. Nucleolar ultrastructure in bovine nuclear transfer embryos

    DEFF Research Database (Denmark)

    Kaňka, Jiří; Smith, Steven Dale; Soloy, Eva

    1999-01-01

    all three cell cycles. In the eight-cell stage embryo, a primary vacuole appeared as an electron lucid area originating in the centre of the nucleolar precursor body. In nuclear transfer embryos reconstructed from nonactivated cytoplasts, the nuclear envelope was fragmented or completely broken down...... vacuoles. A nucleolar precursor body typical for the two-cell stage control embryos was never observed. None of the reconstructed embryos of this group reached the eight-cell stage. Nuclear transfer embryos reconstructed from activated cytoplasts, in contrast, exhibited a complete nuclear envelope at all...... time intervals after fusion. In the two-cell stage nuclear transfer embryo, the originally reticulated nucleolus of the donor blastomere had changed into a typical nucleolar precursor body consisting of a homogeneous fibrillar structure. A primary vacuole appeared in the four-cell stage nuclear...

  3. Two-staged nuclear transfer can enhance the developmental ability of goat-sheep interspecies nuclear transfer embryos in vitro.

    Science.gov (United States)

    Ma, Li-Bing; Cai, Lu; Li, Jia-Jia; Chen, Xiu-Li; Ji, Feng-Yu

    2011-02-01

    The technique of interspecies somatic cell nuclear transfer, in which interspecies cloned embryos can be reconstructed by using domestic animal oocytes as nuclear recipients and endangered animal or human somatic cells as nuclear donors, can afford more opportunities in endangered animal rescue and human tissue transplantation, but the application of this technique is limited by extremely low efficiency which may be attributed to donor nucleus not fully reprogrammed by xenogenic cytoplasm. In this study, goat fetal fibroblasts (GFFs) were used as nuclear donors, in vitro-matured sheep oocytes were used as nuclear recipients, and a two-stage nuclear transfer procedure was performed to improve the developmental ability of goat-sheep interspecies clone embryos. In the first stage nuclear transfer (FSNT), GFFs were injected into the ooplasm of enucleated sheep metaphase-II oocytes, then non-activated reconstructed embryos were cultured in vitro, so that the donor nucleus could be exposed to the ooplasm for a period of time. Subsequently, in the second stage nuclear transfer, FSNT-derived non-activated reconstructed embryo was centrifuged, and the donor nucleus was then transferred into another freshly enucleated sheep oocyte. Compared with the one-stage nuclear transfer, two-stage nuclear transfer could significantly enhance the blastocyst rate of goat-sheep interspecies clone embryos, and this result indicated that longtime exposure to xenogenic ooplasm benefits the donor nucleus to be reprogrammed. The two-stage nuclear transfer procedure has two advantages, one is that the donor nucleus can be exposed to the ooplasm for a long time, the other is that the problem of oocyte aging can be solved.

  4. Developmental toxicity of deltamethrin and 3-phenoxybenzoic acid in embryo-larval stages of zebrafish (Danio rerio).

    Science.gov (United States)

    Kuder, Reshma Shabnam; Gundala, Harold Philip

    2018-03-05

    Synthetic pyrethroids are the major insecticides used widely in agriculture and household pest control. Deltamethrin (DM), a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. 3-Phenoxybenzoic acid (PBA) is the major metabolite formed due to metabolism of DM. In order to illustrate the toxic response of zebrafish embryos/larvae to DM and PBA the present research was carried out. For this 4hpf embryos were treated with two concentrations of DM (100 and 200 μg/L) for 48 h and PBA (1000 and 2000 μg/L) for 96 h or 99.9% ethanol (solvent control). Early life stage parameters were observed at specified time points. DM-treated embryo/larvae exhibited increased mortality, delay in hatching time, decrease in percentage of hatched embryos, increase of heartbeat rate and decrease in blood flow; lightening of body and eye pigmentation in a dose dependent manner. Pericardial and yolk sac edema along with were also caused by DM. Along with these crooked notochord, tail deformation was noticed in hatched and unhatched embryos. In case of PBA treated embryos and larvae, increased embryos/larvae length and yolk sac size were observed. Other abnormalities like edema (yolk sac and pericardial), decreased eye and body pigmentation were also observed but in some embryos only. These were not as severe as observed in parental compound indicating that DM is more toxic than its metabolite PBA. The data contributes to a better understanding of the potential consequences of fish exposed to DM and PBA.

  5. Thermal effect on heart rate and hemodynamics in vitelline arteries of stage 18 chicken embryos.

    Science.gov (United States)

    Lee, Jung Yeop; Lee, Sang Joon

    2010-12-01

    We investigated the thermal effects on heart rate, hemodynamics, and response of vitelline arteries of stage-18 chicken embryos. Heart rate was monitored by a high-speed imaging method, while hemodynamic quantities were evaluated using a particle image velocimetry (PIV) technique. Experiments were carried out at seven different temperatures (36-42 °C with 1 °C interval) after 1h of incubation to stabilize the heart rate. The heart rate increased in a linear manner (r = 0.992). Due to the increased cardiac output (or heart rate), the hemodynamic quantities such as mean velocity (U(mean)), velocity fluctuation (U(fluc)), and peak velocity (U(peak)) also increased with respect to the Womersley number (Ω) in the manner r = 0.599, 0.693, and 0.725, respectively. This indicates that the mechanical force exerting on the vessel walls increases. However, the active response (or regulation) of the vitelline arteries was not observed in this study. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. The early-stage diagnosis of albinic embryos by applying optical coherence tomography

    Science.gov (United States)

    Yang, Bor-Wen; Wang, Shih-Yuan; Wang, Yu-Yen; Cai, Jyun-Jhang; Chang, Chung-Hao

    2013-09-01

    Albinism is a kind of congenital disease of abnormal metabolism. Poecilia reticulata (guppy fish) is chosen as the model to study the development of albinic embryos as it is albinic, ovoviviparous and with short life period. This study proposed an imaging method for penetrative embryo investigation using optical coherence tomography. By imaging through guppy mother’s reproduction purse, we found the embryo’s eyes were the early-developed albinism features. As human’s ocular albinism typically appear at about four weeks old, it is the time to determine if an embryo will grow into an albino.

  7. Differential expression of metallothionein isoforms in terrestrial snail embryos reflects early life stage adaptation to metal stress.

    Science.gov (United States)

    Baurand, Pierre-Emmanuel; Pedrini-Martha, Veronika; de Vaufleury, Annette; Niederwanger, Michael; Capelli, Nicolas; Scheifler, Renaud; Dallinger, Reinhard

    2015-01-01

    The aim of this study was to analyze the expression of three metallothionein (MT) isoform genes (CdMT, CuMT and Cd/CuMT), already known from adults, in the Early Life Stage (ELS) of Cantareus aspersus. This was accomplished by detection of the MT isoform-specific transcription adopting Polymerase Chain Reaction (PCR) amplification and quantitative Real Time (qRT)-PCR of the three MT genes. Freshly laid eggs were kept for 24 hours under control conditions or exposed to three cadmium (Cd) solutions of increasing concentration (5, 10, and 15 mg Cd/L). The transcription of the three MT isoform genes was detected via PCR in 1, 6 and 12-day-old control or Cd-exposed embryos. Moreover, the transcription of this isoform genes during development was followed by qRT-PCR in 6 and 12-day-old embryos. Our results showed that the CdMT and Cd/CuMT genes, but not the CuMT gene, are expressed in embryos at the first day of development. The transcription of the 3 MT genes in control embryos increased with development time, suggesting that the capacities of metal regulation and detoxification may have gradually increased throughout embryogenesis. However in control embryos, the most highly expressed MT gene was that of the Cd/CuMT isoform, whose transcription levels greatly exceeded those of the other two MT genes. This contrasts with the minor significance of this gene in adult snails and suggests that in embryos, this isoform may play a comparatively more important role in metal physiology compared to adult individuals. This function in adult snails appears not to be related to Cd detoxification. Instead, snail embryos responded to Cd exposure by over-expression of the CdMT gene in a concentration-dependent manner, whereas the expression of the Cd/CuMT gene remained unaffected. Moreover, our study demonstrates the ability of snail embryos to respond very early to Cd exposure by up-regulation of the CdMT gene.

  8. The Effect of Cirata Reservoir Sediment on Early Developmental Stage of Common Carp (Cyprinus carpio Embryo

    Directory of Open Access Journals (Sweden)

    Yuni Pujihastuti

    2009-07-01

    Full Text Available Sedimentation at Cirata reservoir may directly and indirectly influence fish particularly fish which have an adhesive characteristic at its early developmental stage such as common carp (Cyprinus carpio. Sample of sediment was collected from Cirata reservoir using Eikmand dredge at a depth of 80 m. The sample was subsequently centrifuged at 5500 rpm for 10 min. The supernatant obtained was then used for toxicity test on common carp at early developmental stage. In this test, four treatments were applied based on the concentration of sediment supernatant, namely: 0, 8.33, 16.60 and 24.90 %. The results showed that a higher sediment supernatant concentration resulted in lower egg yolk absorption rate, lower relative growth rate in length, lower egg yolk efficiency and higher egg and larval abnormality.  Higher sediment supernatant concentration also resulted in lower hatching percentage of common carp larva. The damage of eggs and larval morphologies in treatments with sediment supernatant was likely caused by the presence Pb and organic matters which act in synergy. Keywords :  sediment, Cirata, embryo, common carp   ABSTRAK Sedimentasi di Waduk Cirata secara langsung dan tidak langsung akan berpengaruh terhadap kehidupan ikan khususnya tahap awal perkembangan ikan yang bersifat adhesiveseperti ikan mas (Cyprinus carpio.  Sampel sedimen waduk Cirata diambil dengan Eikmand dredge pada kedalaman 80 m.  Hasil ekstrak di sentrifugasi dengan kecepatan 5500 rpm selama 10 menit untuk diambil air pori sedimennya.  Air pori digunakan sebagai bahan uji toksisitas terhadap perkembangan awal ikan mas dengan perlakuan 0; 8,33; 16,60 dan 24,90 %. Hasil uji toksisitas diperoleh bahwa semakin tinggi konsentrasi air pori dari sediment maka semakin rendah laju penyerapan kuning telur Laju pertumbuhan relatif panjang embrio pada berbagai konsentrasi juga diperoleh bahwa semakin tinggi konsentrasi air sedimen maka semakin rendah laju pertumbuhan relatif

  9. Vitrification in Open and Closed Carriers at Different Cell Stages: Assessment of Embryo Survival, Development, DNA Integrity and Stability during Vapor Phase Storage for Transport

    Directory of Open Access Journals (Sweden)

    Goldberg Jeffrey

    2011-03-01

    Full Text Available Abstract Background High cooling rates with vitrification can be achieved through the use of carriers that allow cryopreservation in fluid volumes Methods Frozen one-cell mouse embryos were thawed and randomly allocated to treatment groups. Embryos were cultured and vitrified at the 8-cell (CL or at the blastocyst (BL stage. The cryoloop, an open carrier was tested against two closed systems, the Cryotip and the HSV straw. Carriers were tested for their ability to maintain embryo viability when held in the vapor phase of a dry shipper for a period of 96 hours. Outcome parameters monitored were embryo survival, recovery, subsequent development and signs of DNA damage. Results A total of 561 embryos were vitrified. The only parameter significantly affected by the type of carrier was the percentage of embryos recovered after warming. Vitrification of both CL and BL stage embryos in the Cryotip resulted in significantly lower recovery rates (P Conclusion This study is one of the first to examine DNA integrity after vitrification on different carriers and at different cell stages. It also provides insight on relative safety of short term vapor storage of vitrified embryos during transport. Within the limits of this study we could not detect an adverse effect of vapor storage on blastomere DNA or other measured outcome parameters.

  10. Identification and quantitative analysis of stage-specific carbohydrates in loblolly pine (Pinus taeda) zygotic embryo and female gametophyte tissues.

    Science.gov (United States)

    Pullman, Gerald S; Buchanan, Mike

    2008-07-01

    Stage-specific analyses of starch and 18 sugars, including pentoses, hexoses, disaccharides, trisaccharides, oligosaccharides and sugar alcohols, were made throughout seed development for zygotic embryo and female gametophyte (FG) tissues of loblolly pine (Pinus taeda L.). Tissue was most often analyzed in triplicate from two open-pollinated families grown in different locations and sampled in different years. Carbohydrates were analyzed by enzymatic assay, high performance liquid chromatography or gas chromatography/mass spectrometry. For all carbohydrates quantified, peak concentrations were higher in embryo tissue than in FG tissue. Significant changes in starch and sugar concentrations occurred over time, with both seed collections showing similar trends in temporal changes. Although concentrations were not always similar, embryo and FG tissues generally showed similar patterns of change in starch and sugar concentrations over time. Total starch concentration was highest during early seed development and decreased as development progressed. The major sugars contributing to osmotic potential during early seed development were D-pinitol, sucrose, fructose and glucose. During mid-seed development, D-pinitol, sucrose, fructose, glucose, melibiose and raffinose provided major contributions to the osmotic environment. During late seed development, sucrose, raffinose, melibiose, stachyose and fructose were the major contributors to osmotic potential. These data suggest stage-specific media composition for each step in the somatic embryogenesis protocol.

  11. Somatic embryogenesis, scanning electron microscopy, histology and biochemical analysis at different developing stages of embryogenesis in six date palm (Phoenix dactylifera L.) cultivars

    Science.gov (United States)

    Aslam, Junaid; Khan, Saeed Ahmad; Cheruth, Abdul Jaleel; Mujib, Abdul; Sharma, Maheshwar Pershad; Srivastava, Prem Shanker

    2011-01-01

    An efficient somatic embryogenesis system has been established in six date palm (Phoenix dactylifera L.) cultivars (Barhee, Zardai, Khalasah, Muzati, Shishi and Zart). Somatic embryogenesis (SE) was growth regulators and cultivars dependent. Friable embryogenic callus was induced from excised shoot tips on MS medium supplemented with various auxins particularly 2,4-dichlorophenoxyacetic acid (2,4-D, 1.5 mg 1−l). Suspension culture increased embryogenesis potentiality. Only a-naphthaleneacetic acid (NAA, 0.5 mg 1−1) produced somatic embryos in culture. Somatic embryos germinated and converted into plantlets in N6-benzyladenine (BAP, 0.75 mg 1−l) added medium following a treatment with thidiazuron (TDZ, 1.0 mg 1−l) for maturation. Scanning electron microscopy showed early stages of somatic embryo particularly, globular types, and was in masses. Different developing stages of embryogenesis (heart, torpedo and cotyledonary) were observed under histological preparation of embryogenic callus. Biochemical screening at various stages of somatic embryogenesis (embryogenic callus, somatic embryos, matured, germinated embryos and converted plantlets) of date palm cultivars has been conducted and discussed in detail. The result discussed in this paper indicates that somatic embryos were produced in numbers and converted plantlets can be used as a good source of alternative propagation. Genetic modification to the embryo precursor cell may improve the fruit quality and yield further. PMID:23961149

  12. Changes in the transcriptome of morula-stage bovine embryos caused by heat shock: relationship to developmental acquisition of thermotolerance

    Directory of Open Access Journals (Sweden)

    Sakatani Miki

    2013-01-01

    Full Text Available Abstract Background While initially sensitive to heat shock, the bovine embryo gains thermal resistance as it progresses through development so that physiological heat shock has little effect on development to the blastocyst stage by Day 5 after insemination. Here, experiments using 3’ tag digital gene expression (3’DGE and real-time PCR were conducted to determine changes in the transcriptome of morula-stage bovine embryos in response to heat shock (40 degrees C for 8 h that could be associated with thermotolerance. Results Using 3’DGE, expression of 173 genes were modified by heat shock, with 94 genes upregulated by heat shock and 79 genes downregulated by heat shock. A total of 38 differentially-regulated genes were associated with the ubiquitin protein, UBC. Heat shock increased expression of one heat shock protein gene, HSPB11, and one heat shock protein binding protein, HSPBP1, tended to increase expression of HSPA1A and HSPB1, but did not affect expression of 64 other genes encoding heat shock proteins, heat shock transcription factors or proteins interacting with heat shock proteins. Moreover, heat shock increased expression of five genes associated with oxidative stress (AKR7A2, CBR1, GGH, GSTA4, and MAP2K5, decreased expression of HIF3A, but did not affect expression of 42 other genes related to free radical metabolism. Heat shock also had little effect on genes involved in embryonic development. Effects of heat shock for 2, 4 and 8 h on selected heat shock protein and antioxidant genes were also evaluated by real-time PCR. Heat shock increased steady-state amounts of mRNA for HSPA1A (PHSP90AA1 (PSOD1 or CAT. Conclusions Changes in the transcriptome of the heat-shocked bovine morula indicate that the embryo is largely resistant to effects of heat shock. As a result, transcription of genes involved in thermal protection is muted and there is little disruption of gene networks involved in embryonic development. It is likely that

  13. Single stage incubators and Hypercapnia during incubation affect the vascularization of the chorioallantoic membrane in broiler embryos.

    Science.gov (United States)

    Fernandes, J I M; Bortoluzzi, C; Schmidt, J M; Scapini, L B; Santos, T C; Murakami, A E

    2017-01-01

    Incubation management can have direct effects on neonate health and consequently affect post-hatching development. The effects of incubation in multiple and single stage incubators with different concentrations of CO 2 were evaluated in terms of the vessel density in the chorioallantoic membrane, hatching, heart morphology, and body development of the neonate up to the tenth day. A total of 2,520 fertile eggs were used and distributed in a completely randomized design with 4 levels of CO 2 in 4 single-stage incubators (4,000; 6,000; 8,000; and 10,000 ppm) and a control treatment based on multiple-stage incubation, totaling 5 treatments. The levels of CO 2 were used during the first 10 d of the incubation period, and after this period, all eggs were submitted to the same level of CO 2 (4,000 ppm). Eggs that were incubated in multiple-stage incubators presented a lower percentage of vessels in the chorioallantoic membrane, lower yolk absorption by the embryo, wall depth of the right ventricle, and greater humidity losses in the eggs when compared to eggs in the single-stage incubators. The eggs submitted to hypercapnia, between 5,000 and 6,000 ppm of CO 2 , had a higher percentage of vessels in the chorioallantoic membrane; the embryos originating from these eggs had higher weight, with higher relative weight of the liver. However, the same levels reduced the yolk absorption. Single-stage incubation with moderate levels of hypercapnia is an efficient tool to be adopted by the hatcheries when attempting to improve chick quality. © 2016 Poultry Science Association Inc.

  14. Proteomic analysis of the Gallus gallus embryo at stage-29 of development.

    Science.gov (United States)

    Agudo, David; Agudo Garcillán, David; Gómez-Esquer, Francisco; Díaz-Gil, Gema; Martínez-Arribas, Fernando; Delcán, José; Schneider, José; Palomar, María Angustias; Linares, Rafael

    2005-12-01

    The chicken (Gallus gallus) is one of the primary models for embryological and developmental studies. In order to begin to understand the molecular mechanisms underlying the normal and abnormal development of the chicken, we used 2-DE to construct a whole-embryo proteome map. Proteins were separated by IEF on IPG strips, and by 11% SDS-PAGE) gels. Protein identification was performed by means of PMF with MALDI-TOF-MS. In all, 105 protein spots were identified, 35 of them implicated in embryo development, 10 related with some diseases, and 16, finally, being proteins that have never been identified, purified or characterized in the chicken before. This map will be updated continuously and will serve as a reference database for investigators, studying changes at the protein level under different physiological conditions.

  15. Silencing CENPF in bovine preimplantation embryo induces arrest at 8-cell stage

    Czech Academy of Sciences Publication Activity Database

    Toralová, Tereza; Šušor, Andrej; Němcová, Lucie; Kepková, Kateřina; Kaňka, Jiří

    2009-01-01

    Roč. 138, č. 5 (2009), s. 783-791 ISSN 1470-1626 R&D Projects: GA ČR GA523/06/1226; GA ČR(CZ) GD204/05/H023 Institutional research plan: CEZ:AV0Z50450515 Keywords : CENPF * bovine embryo * preimplantation development Subject RIV: GI - Animal Husbandry ; Breeding Impact factor: 2.579, year: 2009

  16. A catalog of Xenopus tropicalis transcription factors and their regional expression in the early gastrula stage embryo.

    Science.gov (United States)

    Blitz, Ira L; Paraiso, Kitt D; Patrushev, Ilya; Chiu, William T Y; Cho, Ken W Y; Gilchrist, Michael J

    2017-06-15

    Gene regulatory networks (GRNs) involve highly combinatorial interactions between transcription factors and short sequence motifs in cis-regulatory modules of target genes to control cellular phenotypes. The GRNs specifying most cell types are largely unknown and are the subject of wide interest. A catalog of transcription factors is a valuable tool toward obtaining a deeper understanding of the role of these critical effectors in any biological setting. Here we present a comprehensive catalog of the transcription factors for the diploid frog Xenopus tropicalis. We identify 1235 genes encoding DNA-binding transcription factors, comparable to the numbers found in typical mammalian species. In detail, the repertoire of X. tropicalis transcription factor genes is nearly identical to human and mouse, with the exception of zinc finger family members, and a small number of species/lineage-specific gene duplications and losses relative to the mammalian repertoires. We applied this resource to the identification of transcription factors differentially expressed in the early gastrula stage embryo. We find transcription factor enrichment in Spemann's organizer, the ventral mesoderm, ectoderm and endoderm, and report 218 TFs that show regionalized expression patterns at this stage. Many of these have not been previously reported as expressed in the early embryo, suggesting thus far unappreciated roles for many transcription factors in the GRNs regulating early development. We expect our transcription factor catalog will facilitate myriad studies using Xenopus as a model system to understand basic biology and human disease. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Single cell proteomics using frog (Xenopus laevis) blastomeres isolated from early stage embryos, which form a geometric progression in protein content

    OpenAIRE

    Sun, Liangliang; Dubiak, Kyle M.; Peuchen, Elizabeth H.; Zhang, Zhenbin; Zhu, Guijie; Huber, Paul W.; Dovichi, Norman J.

    2016-01-01

    Single cell analysis is required to understand cellular heterogeneity in biological systems. We propose that single cells (blastomeres) isolated from early stage invertebrate, amphibian, or fish embryos are ideal model systems for the development of technologies for single cell analysis. For these embryos, although cell cleavage is not exactly symmetric, the content per blastomere decreases roughly by half with each cell division, creating a geometric progression in cellular content. This pro...

  18. Lipofection of siRNA into bovine 8-16-cell stage embryos using zona removal and the well-of-the-well culture system.

    Science.gov (United States)

    Ikeda, Shuntaro; Sugimoto, Miki; Kume, Shinichi

    2018-04-13

    Bovine preimplantation embryos exhibit dramatic biological changes between before and after the 8-16-cell stage. Here we report a simple lipofection method to transfect siRNA into bovine 8-16-cell stage embryos using zona removal and the well-of-the-well (WOW) culture system. Bovine one-cell embryos produced in vitro were freed from the zona pellucida and cultured up to the 8-16-cell stage in WOW dishes. The 8-16-cell embryos were lipofected with siRNA and the transfection efficiency was assessed at 48 h of transfection. Lipofection with a red fluorescent non-targeting siRNA revealed the importance of zona removal for transfection of siRNA into embryos. Using this method, we knocked down the methionine adenosyltransferase 2A (MAT2A) gene, achieving a significant reduction in MAT2A expression (P < 0.05) concomitant with the marked inhibition of blastocyst development. Our proposed method, tentatively named 'Octo-lipofection', may be useful to analyze gene functions in bovine preimplantation embryos without expensive equipment and skill-intensive techniques.

  19. Progesterone elevation on the day of human chorionic gonadotropin administration adversely affects the outcome of IVF with transferred embryos at different developmental stages.

    Science.gov (United States)

    Huang, Yan; Wang, En-Yin; Du, Qing-Yun; Xiong, Yu-Jing; Guo, Xiao-Yi; Yu, Yi-Ping; Sun, Ying-Pu

    2015-08-04

    The effect of progesterone elevation (PE) on the day of human chorionic gonadotropin (hCG) administration on the pregnancy outcomes of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles is a matter of ongoing debate. The replacement of cleavage-stage embryos with blastocyst-stage embryos for transfer was proposed to avoid the possible impairment of PE in fresh cycles. This study aimed to assess the association between PE on the day of human chorionic gonadotropin (hCG) administration and clinical pregnancy rates (CPRs) in IVF/ICSI cycles with embryos transferred at different developmental stages (cleavage and blastocyst). Moreover, a secondary aim was to determine the thresholds at which PE has a detrimental effect on CPRs. This single-center retrospective cohort study included more than 10,000 patients undergoing day 3 cleavage-stage embryo transfer (ET) and 1146 patients undergoing day 5 blastocyst-stage embryo transfer (ET) using gonadotropin and GnRH agonist for controlled ovarian stimulation. Serum PE was inversely associated with CPRs in both cleavage- and blastocyst-stage ET cycles. In the day 3 ET cycles, CPRs (progesterone levels < 0.5 ng/ml, 49.2 %) significantly declined when the progesterone concentration reached 1.0 ng/ml (45.5 %) and decreased further when the progesterone concentration increased to 1.5 ng/ml (36.2 %). In the day 5 blastocyst-stage ET cycles, patients with serum progesterone levels ≥1.75 ng/ml had significantly lower CPRs (31.3 % VS. 41.4 %, p < 0.001) compared to patients with serum progesterone levels <1.75 ng/ml. The negative association of PE with CPRs was noted in both ET groups, even after adjusting for confounders. Furthermore, the developmental stage of the transferred embryos was not linked to the effect of PE on CPRs because the interaction between the developmental stage of the transferred embryos and PE was not significant. PE on the day of hCG administration is associated with

  20. Transcriptome profiles of embryos before and after cleavage in Eriocheir sinensis: identification of developmental genes at the earliest stages

    Science.gov (United States)

    Hui, Min; Cui, Zhaoxia; Liu, Yuan; Song, Chengwen

    2017-07-01

    In crab, embryogenesis is a complicated developmental program marked by a series of critical events. RNA-Sequencing technology offers developmental biologists a way to identify many more developmental genes than ever before. Here, we present a comprehensive analysis of the transcriptomes of Eriocheir sinensis oosperms (Os) and embryos at the 2-4 cell stage (Cs), which are separated by a cleavage event. A total of 18 923 unigenes were identified, and 403 genes matched with gene ontology (GO) terms related to developmental processes. In total, 432 differentially expressed genes (DEGs) were detected between the two stages. Nine DEGs were specifically expressed at only one stage. These DEGs may be relevant to stage-specific molecular events during development. A number of DEGs related to `hedgehog signaling pathway', `Wnt signaling pathway' `germplasm', `nervous system', `sensory perception' and `segment polarity' were identified as being up-regulated at the Cs stage. The results suggest that these embryonic developmental events begin before the early cleavage event in crabs, and that many of the genes expressed in the two transcriptomes might be maternal genes. Our study provides ample information for further research on the molecular mechanisms underlying crab development.

  1. Absence of Sperm Factors as in the Parthenogenesis Does Not Interfere on Bovine Embryo Sensitiveness to Heat Shock at Pre-Implantation Stage.

    Science.gov (United States)

    Camargo, L S A; Paludo, F; Pereira, M M; Wohlres-Viana, S; Gioso, M M; Carvalho, B C; Quintao, C C R; Viana, J H M

    2016-02-01

    Oocyte has been considered the major contributor for embryo thermo-tolerance. However, it was shown that sperm factors can be transferred to the oocyte during fertilization, raising the question of whether the absence of such factors could interfere on embryo thermo-tolerance. In this study, we used parthenogenesis to generate bovine embryos without spermatozoa in order to test whether the absence of sperm factors could influence their thermo-sensitiveness at early stages. In vitro fertilized (IVF) and parthenogenetic (PA) embryos at 44 h post-insemination/chemical activation were exposed to 38.5°C (control) or 41°C (heat shock) for 12 h and then developed for 48 h and up to blastocyst stage. Apoptosis index and expression of PRDX1, GLUT1, GLUT5 and IGF1r genes in blastocysts derived from heat-shocked embryos were also evaluated. The heat shock decreased the blastocyst rate at day seven (p 0.05) between method of activation (IVF and PA) and temperature (38.5°C or 41.5°C) for all developmental parameters evaluated. Expression of GLUT1 gene was downregulated (p < 0.05) by heat shock in both IVF and PA blastocyst whereas expression of GLUT5 and IGF1r genes was downregulated (p < 0.05) by heat shock in PA blastocysts. Those data show that the heat shock affects negatively the embryo development towards blastocysts stage, increases the apoptotic index and disturbed the expression of some genes in both IVF and PA embryos, indicating that the presence or absence of sperm factors does not influence the sensitivity of the bovine embryo to heat shock. © 2015 Blackwell Verlag GmbH.

  2. Necropsy findings in American alligator late-stage embryos and hatchlings from northcentral Florida lakes contaminated with organochlorine pesticides

    Science.gov (United States)

    Sepulveda, M.S.; Del, Piero F.; Wiebe, J.J.; Rauschenberger, H.R.; Gross, T.S.

    2006-01-01

    Increased American alligator (Alligator mississippiensis) embryo and neonatal mortality has been reported from several northcentral Florida lakes contaminated with old-use organochlorine pesticides (OCPs). However, a clear relationship among these contaminants and egg viability has not been established, suggesting the involvement of additional factors in these mortalities. Thus, the main objective of this study was to determine the ultimate cause of mortality of American alligator late-stage embryos and hatchlings through the conduction of detailed pathological examinations, and to evaluate better the role of OCPs in these mortalities. Between 2000 and 2001, 236 dead alligators were necropsied at or near hatching (after ???65 days of artificial incubation and up to 1 mo of age posthatch). Dead animals were collected from 18 clutches ranging in viability from 0% to 95%. Total OCP concentrations in yolk ranged from ???100 to 52,000 ??g/kg, wet weight. The most common gross findings were generalized edema (34%) and organ hyperemia (29%), followed by severe emaciation (14%) and gross deformities (3%). Histopathologic examination revealed lesions in 35% of the animals, with over half of the cases being pneumonia, pulmonary edema, and atelectasis. Within and across clutches, dead embryos and hatchlings compared with their live cohorts were significantly smaller and lighter. Although alterations in growth and development were not related to yolk OCPs, there was an increase in prevalence of histologic lesions in clutches with high OCPs. Overall, these results indicate that general growth retardation and respiratory abnormalities were a major contributing factor in observed mortalities and that contaminants may increase the susceptibility of animals to developing certain pathologic conditions. ?? Wildlife Disease Association 2006.

  3. A comparison of psychological functioning in couples undergoing frozen-thawed embryo replacement in various stages of treatment using the Mean Affect Adjective Check List (MAACL).

    Science.gov (United States)

    Ismail, W A; Menezes, M Q; Martin, C W; Thong, K J

    2004-09-01

    The objectives were to identify the stage(s) of frozen embryo replacement cycle where the couples are most vulnerable to psychological dysfunction. Assessment was performed by using the Mean Affect Adjective Check-List (MAACL). Thirty couples completed the MAACL questionnaire at the following stages: (a) pretreatment (visit 1), (b) before embryo transfer (visit 2), and (c) before pregnancy test (visit 3). Each partner had to complete a separate questionnaire set. For both partners, the depression score for visit 3 was significantly higher and the sensation seeking and positive affect scores were significantly lower than the corresponding scores for earlier visits. Anxiety scores were similar for all visits. For men, the hostility scores were significantly higher between visits 1 and 2 while in women the same was reported between visits 3 and 2. Psychological counselling should be targeted at couples especially after embryo transfer. MAACL is a useful method for measuring psychological dysfunction in these couples.

  4. The Relationship between Cell Number, Division Behavior and Developmental Potential of Cleavage Stage Human Embryos: A Time-Lapse Study.

    Directory of Open Access Journals (Sweden)

    Xiangyi Kong

    Full Text Available Day 3 cleavage embryo transfer is routine in many assisted reproductive technology centers today. Embryos are usually selected according to cell number, cell symmetry and fragmentation for transfer. Many studies have showed the relationship between cell number and embryo developmental potential. However, there is limited understanding of embryo division behavior and their association with embryo cell number and developmental potential. A retrospective and observational study was conducted to investigate how different division behaviors affect cell number and developmental potential of day 3 embryos by time-lapse imaging. Based on cell number at day 3, the embryos (from 104 IVF/intracytoplasmic sperm injection (ICSI treatment cycles, n = 799 were classified as follows: less than 5 cells (10C; n = 42. Division behavior, morphokinetic parameters and blastocyst formation rate were analyzed in 5 groups of day 3 embryos with different cell numbers. In 10C embryos increased compared to 7-8C embryos (45.8%, 33.3% vs. 11.1%, respectively. In ≥5C embryos, FR and DC significantly reduced developmental potential, whereas 10C. In NB embryos, the cell cycle elongation or shortening was the main cause for abnormally low or high cell number, respectively. After excluding embryos with abnormal division behaviors, the developmental potential, implantation rate and live birth rate of day 3 embryos increased with cell number.

  5. EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

    Energy Technology Data Exchange (ETDEWEB)

    Greeley Jr, Mark Stephen [ORNL; Elmore, Logan R [ORNL; McCracken, Kitty [ORNL

    2012-05-01

    On December 22, 2008, a dike containing fly ash and bottom ash in an 84-acre complex of the Tennessee Valley Authority's (TVA) Kingston Steam Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits extended as far as 4 miles upstream (Emory River mile 6) of the Plant, and some ash was carried as far downstream as Tennessee River mile 564 ({approx}4 miles downstream of the Tennessee River confluence with the Clinch River). A byproduct of coal burning power plants, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be toxic to biological systems. The effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to be the effects of specific ash constituents, especially selenium, on fish early life stages. Uptake by adult female fish of fly ash constituents through the food chain and subsequent maternal transfer of contaminants to the developing eggs is thought to be the primary route of selenium exposure to larval fish (Woock and others 1987, Coyle and others 1993, Lemly 1999, Moscatello and others 2006), but direct contact of the fertilized eggs and developing embryos to ash constituents in river water and sediments is also a potential risk factor (Woock and others 1987, Coyle and others 1993, Jezierska and others 2009). To address the risk of fly ash from the Kingston spill to the reproductive health of downstream fish populations, ORNL has undertaken a series of studies in collaboration with TVA including: (1) a field study of the bioaccumulation of fly ash constituents in fish ovaries and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill; (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (reported in the

  6. Effects of the ionizing radiations in the different stages of the embryo-fetal development

    International Nuclear Information System (INIS)

    Perez, Maria R.

    2001-01-01

    'In utero' exposures to ionizing radiation are a very important subject in radiological protection concerning not only the prevention but also the estimation of the associated risks. In these situations the perception of risks by the pregnant woman and the involved professionals could not always be correlated with their objective magnitude. In this communication we describe the effects of prenatal exposure to ionizing radiation, the thresholds and their relation with the gestational age, taking into account occupationally exposed women, patients undergoing medical procedures and public members. The dose estimation, the evaluation of the potential associated risks and the relation with the spontaneous incidence of the considered effects are analyzed in the framework of the basic principles of radiological protection. Most of diagnostic procedures properly done do not imply induction of deterministic effects in embryo/fetus. Therapeutical procedures and accidental overexposures could be associated with significant risks of deterministic effects. Childhood cancer induction is an stochastic effect without threshold and every 'in utero' exposure will increase their probability. (author)

  7. Runx expression is mitogenic and mutually linked to Wnt activity in blastula-stage sea urchin embryos.

    Directory of Open Access Journals (Sweden)

    Anthony J Robertson

    Full Text Available The Runt homology domain (Runx defines a metazoan family of sequence-specific transcriptional regulatory proteins that are critical for animal development and causally associated with a variety of mammalian cancers. The sea urchin Runx gene SpRunt-1 is expressed throughout the blastula stage embryo, and is required globally during embryogenesis for cell survival and differentiation.Depletion of SpRunt-1 by morpholino antisense-mediated knockdown causes a blastula stage deficit in cell proliferation, as shown by bromodeoxyuridine (BrdU incorporation and direct cell counts. Reverse transcription coupled polymerase chain reaction (RT-PCR studies show that the cell proliferation deficit is presaged by a deficit in the expression of several zygotic wnt genes, including wnt8, a key regulator of endomesoderm development. In addition, SpRunt-1-depleted blastulae underexpress cyclinD, an effector of mitogenic Wnt signaling. Blastula stage cell proliferation is also impeded by knockdown of either wnt8 or cyclinD. Chromatin immunoprecipitation (ChIP indicates that Runx target sites within 5' sequences flanking cyclinD, wnt6 and wnt8 are directly bound by SpRunt-1 protein at late blastula stage. Furthermore, experiments using a green fluorescent protein (GFP reporter transgene show that the blastula-stage operation of a cis-regulatory module previously shown to be required for wnt8 expression (Minokawa et al., Dev. Biol. 288: 545-558, 2005 is dependent on its direct sequence-specific interaction with SpRunt-1. Finally, inhibitor studies and immunoblot analysis show that SpRunt-1 protein levels are negatively regulated by glycogen synthase kinase (GSK-3.These results suggest that Runx expression and Wnt signaling are mutually linked in a feedback circuit that controls cell proliferation during development.

  8. [Demonstration, by means of electron microscopy, of the penetration of somitic cells into the mesoblast of the limb buds of reptile embryos (Anguis fragilis, Lacerta viridis)].

    Science.gov (United States)

    Raynaud, A; Adrian, M

    1975-01-01

    An electron microscopic study of the components of anterior limb buds of the slow-worm (Anguis fragilis) and of the green lizard (Lacerta viridis) (embryos of Anguis whose allantoic bud reach 0,7 to 4 mm of length; embryos of Lacerta 2 to 7 days old) provides data on the cytological characteristics of the components of the limb bud at these early stages. 1. The cells of the distal extremity of the somitic processes extending in the limb bud of Anguis and Lacerta, are elongated cells with ovoid nuclei containing large nucleolus; they possess mitochondria always thin and with dense matrix; they are rich in lipid droplets; they possess cilia; they are devoid of myofilaments; endoplasmic reticulum, free ribosomes and polyribosomes are abundant. Golgi networks display signs of activity. These characteristics are also observed in the cells of the "dermatome" layer of the dermo-myotome; and so, it appears probable that the cells of the "dermatome". Furthermore, in Anguis embryos, the cells of the distal extremities of the somitic processes possess numerous lysosomes and a certain number of cells among them, degenerate early. 2. The somatopleural mesoblastic cells of the limb bud of Anguis and Lacerta embryos keep the characters of the cells of the mesodermic layer of lateral plate from which they originate; they have rounded nuclei, cilia, and their mitochondria are always larger and more transparent to electrons, than the ones of cells of the somitic processes and of cells of the epiblastic apical crest. Golgi networks are well developped, endoplasmic reticulum is abundant, lipid droplets are rare. 3. The processes of somites which extend in the dorsal part of the limb bud of Anguis embryos are cords of cells with thin lumina; at the stage of the allantoic bud of 0,6 to 0,8 mm long, the distal extremity of these processes dislocate in group of cells which afterwards dissociate, releasing individual somitic cells which are integrated among the mesoblastic somatopleural

  9. Confinement and clearance of OCT4 in the porcine embryo at stereomicroscopically defined stages around gastrulation

    DEFF Research Database (Denmark)

    Vejlsted, Morten; Offenberg, Hanne Kjær; Thorup, Flemming

    2006-01-01

    maintaining expression of OCT4 at the end of gastrulation. In the ectodermal and mesodermal cell lineages, OCT4 became undetectable at the neural groove and somite stage, respectively. As in the mouse, PGCs showed onset of c-kit expression when located in extraembryonal compartments. They appeared to follow...... the endoderm during extraembryonal allocation and the mesoderm on return to the genital ridge....

  10. Developmental toxicity and induction of vitellogenin in embryo-larval stages of zebrafish (Danio rerio) exposed to methyl Paraben.

    Science.gov (United States)

    Dambal, Vrinda Yatin; Selvan, Karthikeyan Ponnien; Lite, Christy; Barathi, S; Santosh, Winkins

    2017-07-01

    MethylParaben (MP), a methyl ester of p-hydroxybenzoic acid, is used as an anti-microbial preservative in foods, drugs and cosmetics for decades. It enters the aquatic environment, and can have toxic effects on aquatic organisms. Little is known on the developmental toxicity of MP exposure to zebrafish during early life stages. In this study, the developmental effects of MP were evaluated in embryo-larval zebrafish (at concentrations ranging from 100μM, 200μM, 400µM, 800μM and 1000μM for 96h post fertilization (hpf). The survival, hatching, heart beat rate and developmental abnormalities were observed in the embryos exposed to MP. MP exposure resulted in decreased heart rate and hatching rate. Defects including pericardial edema blood cell accumulation and bent spine were observed in all the treated concentration, except at 100μM. With increasing concentrations, the frequency of these defects increased. The 96 hpf LC 50 of MP was calculated to be 428μM (0.065mg/L). Furthermore, RT-PCR result showed that in larval zebrafish exposed to 100μM (0.015mg/L) of MP till 96 hpf, expression of vitellogenin I (Vtg -I) was significantly upregulated compared to the control group. This data suggest that even though lower concentrations of MP do not cause phenotypic malformations, it leads to dysregulated expression of estrogenic biomarker gene Vtg-I. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. In situ fatigue loading stage inside scanning electron microscope

    Science.gov (United States)

    Telesman, Jack; Kantzos, Peter; Brewer, David

    1988-01-01

    A fatigue loading stage inside a scanning electron microscopy (SEM) was developed. The stage allows dynamic and static high-magnification and high-resolution viewing of the fatigue crack initiation and crack propagation processes. The loading stage is controlled by a closed-loop servohydraulic system. Maximum load is 1000 lb (4450 N) with test frequencies ranging up to 30 Hz. The stage accommodates specimens up to 2 inches (50 mm) in length and tolerates substantial specimen translation to view the propagating crack. At room temperature, acceptable working resolution is obtainable for magnifications ranging up to 10,000X. The system is equipped with a high-temperature setup designed for temperatures up to 2000 F (1100 C). The signal can be videotaped for further analysis of the pertinent fatigue damage mechanisms. The design allows for quick and easy interchange and conversion of the SEM from a loading stage configuration to its normal operational configuration and vice versa. Tests are performed entirely in the in-situ mode. In contrast to other designs, the NASA design has greatly extended the life of the loading stage by not exposing the bellows to cyclic loading. The loading stage was used to investigate the fatigue crack growth mechanisms in the (100)-oriented PWA 1480 single-crystal, nickel-based supperalloy. The high-magnification observations revealed the details of the crack growth processes.

  12. Transmission electron microscope studies of the nuclear envelope in Caenorhabditis elegans embryos.

    Science.gov (United States)

    Cohen, Merav; Tzur, Yonatan B; Neufeld, Esther; Feinstein, Naomi; Delannoy, Michael R; Wilson, Katherine L; Gruenbaum, Yosef

    2002-01-01

    Nuclear membranes and nuclear pore complexes (NPCs) are conserved in both animals and plants. However, the lamina composition and the dimensions of NPCs vary between plants, yeast, and vertebrates. In this study, we established a protocol that preserves the structure of Caenorhabditis elegans embryonic cells for high-resolution studies with thin-section transmission electron microscopy (TEM). We show that the NPCs are bigger in C. elegans embryos than in yeast, with dimensions similar to those in higher eukaryotes. We also localized the C. elegans nuclear envelope proteins Ce-lamin and Ce-emerin by pre-embedding gold labeling immunoelectron microscopy. Both proteins are present at or near the inner nuclear membrane. A fraction of Ce-lamin, but not Ce-emerin, is present in the nuclear interior. Removing the nuclear membranes leaves both Ce-lamin and Ce-emerin associated with the chromatin. Eliminating the single lamin protein caused cell death as visualized by characteristic changes in nuclear architecture including condensation of chromatin, clustering of NPCs, membrane blebbing, and the presence of vesicles inside the nucleus. Taken together, these results show evolutionarily conserved protein localization, interactions, and functions of the C. elegans nuclear envelope.

  13. Annotating and quantifying pri-miRNA transcripts using RNA-Seq data of wild type and serrate-1 globular stage embryos of Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Daniel Lepe-Soltero

    2017-12-01

    Full Text Available The genome annotation for the model plant Arabidopsis thaliana does not include the primary transcripts from which MIRNAs are processed. Here we present and analyze the raw mRNA sequencing data from wild type and serrate-1 globular stage embryos of A. thaliana, ecotype Columbia. Because SERRATE is required for pri-miRNA processing, these precursors accumulate in serrate-1 mutants, facilitating their detection using standard RNA-Seq protocols. We first use the mapping of the RNA-Seq reads to the reference genome to annotate the potential primary transcripts of MIRNAs expressed in the embryo. We then quantify these pri-miRNAs in wild type and serrate-1 mutants. Finally, we use differential expression analysis to determine which are up-regulated in serrate-1 compared to wild type, to select the best candidates for bona fide pri-miRNAs expressed in the globular stage embryos. In addition, we analyze a previously published RNA-Seq dataset of wild type and dicer-like 1 mutant embryos at the globular stage [1]. Our data are interpreted and discussed in a separate article [2].

  14. Annotating and quantifying pri-miRNA transcripts using RNA-Seq data of wild type and serrate-1 globular stage embryos of Arabidopsis thaliana.

    Science.gov (United States)

    Lepe-Soltero, Daniel; Armenta-Medina, Alma; Xiang, Daoquan; Datla, Raju; Gillmor, C Stewart; Abreu-Goodger, Cei

    2017-12-01

    The genome annotation for the model plant Arabidopsis thaliana does not include the primary transcripts from which MIRNAs are processed. Here we present and analyze the raw mRNA sequencing data from wild type and serrate-1 globular stage embryos of A. thaliana , ecotype Columbia. Because SERRATE is required for pri-miRNA processing, these precursors accumulate in serrate-1 mutants, facilitating their detection using standard RNA-Seq protocols. We first use the mapping of the RNA-Seq reads to the reference genome to annotate the potential primary transcripts of MIRNAs expressed in the embryo. We then quantify these pri-miRNAs in wild type and serrate-1 mutants. Finally, we use differential expression analysis to determine which are up-regulated in serrate-1 compared to wild type, to select the best candidates for bona fide pri-miRNAs expressed in the globular stage embryos. In addition, we analyze a previously published RNA-Seq dataset of wild type and dicer-like 1 mutant embryos at the globular stage [1]. Our data are interpreted and discussed in a separate article [2].

  15. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    International Nuclear Information System (INIS)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L.; Vankerkom, J.

    1995-01-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy

  16. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L. [Laboratory of Radiobiology, Department of Radioprotection, CEN/SCK, Mol (Belgium); Vankerkom, J. [Division of Environmental Research, VITO, Mol (Belgium)

    1995-11-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy.

  17. A simplified table for staging embryos of the pipid frog Pipa arrabali

    Directory of Open Access Journals (Sweden)

    OLÍVIA G.S. ARAÚJO

    Full Text Available ABSTRACT Pipa is a Neotropical genus of frogs that dwell in freshwater environments. It includes four species that lack free-swimming larvae (P. aspera, P. arrabali, P. pipa, and P. snethlageae and three with tadpoles (P. carvalhoi, P. myersi, and P. parva. Developmental tables such as the one proposed by Nieuwkoop and Faber might be useful for Pipa species with tadpoles. However, for the other Pipa species, to determine stages by this table or by any of the tables already prepared for frogs without tadpoles (e.g., Crinia nimbus, Eleutherodactylus coqui, and Oreobates barituensis is impossible. By using embryonic, juvenile, and subadult specimens, we generated a staging table for P. arrabali, from the moment limb buds were first observed until birth, based on diagnostic features such as snout-vent length; growth, morphology, and reabsorption of the external tail; growth and differentiation of fore and hind limbs; development of intestine and vent tube; position of the angle of the mouth relative to nostrils and eyes; and color of preserved individuals. Based on these observations, we discuss some noteworthy traits (e.g., posture of hands and feet. We also compare the pattern of development of P. arrabali with that of other anuran species (with and without tadpoles.

  18. A Thermoelectric Generation System and Its Power Electronics Stage

    Science.gov (United States)

    Gao, Junling; Sun, Kai; Ni, Longxian; Chen, Min; Kang, Zhengdong; Zhang, Li; Xing, Yan; Zhang, Jianzhong

    2012-06-01

    The electricity produced by a thermoelectric generator (TEG) must satisfy the requirements of specific loads given the signal level, stability, and power performance. In the design of such systems, one major challenge involves the interactions between the thermoelectric power source and the power stage and signal-conditioning circuits of the load, including DC-DC conversion, the maximum power point tracking (MPPT) controller, and other power management controllers. In this paper, a survey of existing power electronics designs for TEG systems is presented first. Second, a flat, wall-like TEG system consisting of 32 modules is experimentally optimized, and the improved power parameters are tested. Power-conditioning circuitry based on an interleaved boost DC-DC converter is then developed for the TEG system in terms of the tested power specification. The power electronics design features a combined control scheme with an MPPT and a constant output voltage as well as the low-voltage and high-current output characteristics of the TEG system. The experimental results of the TEG system with the power electronics stage and with purely resistive loads are compared. The comparisons verify the feasibility and effectiveness of the proposed design. Finally, the thermal-electric coupling effects caused by current-related heat source terms, such as the Peltier effect etc., are reported and discussed, and the potential influence on the power electronics design due to such coupling is analyzed.

  19. Maintenance ofMestimprinted methylation in blastocyst-stage mouse embryos is less stable than other imprinted loci following superovulation or embryo culture.

    Science.gov (United States)

    Velker, Brenna A M; Denomme, Michelle M; Krafty, Robert T; Mann, Mellissa R W

    2017-07-01

    Assisted reproductive technologies are fertility treatments used by subfertile couples to conceive their biological child. Although generally considered safe, these pregnancies have been linked to genomic imprinting disorders, including Beckwith-Wiedemann and Silver-Russell Syndromes. Silver-Russell Syndrome is a growth disorder characterized by pre- and post-natal growth retardation. The Mest imprinted domain is one candidate region on chromosome 7 implicated in Silver-Russell Syndrome. We have previously shown that maintenance of imprinted methylation was disrupted by superovulation or embryo culture during pre-implantation mouse development. For superovulation, this disruption did not originate in oogenesis as a methylation acquisition defect. However, in comparison to other genes, Mest exhibits late methylation acquisition kinetics, possibly making Mest more vulnerable to perturbation by environmental insult. In this study, we present a comprehensive evaluation of the effects of superovulation and in vitro culture on genomic imprinting at the Mest gene. Superovulation resulted in disruption of imprinted methylation at the maternal Mest allele in blastocysts with an equal frequency of embryos having methylation errors following low or high hormone treatment. This disruption was not due to a failure of imprinted methylation acquisition at Mest in oocytes. For cultured embryos, both the Fast and Slow culture groups experienced a significant loss of maternal Mest methylation compared to in vivo -derived controls. This loss of methylation was independent of development rates in culture. These results indicate that Mest is more susceptible to imprinted methylation maintenance errors compared to other imprinted genes.

  20. Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

    International Nuclear Information System (INIS)

    Kikuchi, O.K.; Okazaki, K.; Kawano, T.; Ribeiro, A.A.G.F.C.

    1988-09-01

    Ultrastructural studies of Biomphalaria glabrata embryos (MOllusca: Gastropoda), and important snail vector of schistosomiasis has not been explored. In the present work it was evaluated a suitable electron microscopical technique for embryos processing. Promising results was obtained with double fixation in 1% glutaraldehyde plus 1% osmium tetroxide in 0.05 M cacodylate buffer (pH 7.4), preliminary staining overnight in 1% uranyl acetate and embedding in EPON or Polylite under vacuum. It was used embryos at young trochophore stage wich is characterized by active organogenesis. Some ultrastructural aspects of B. glabrata embryos cells are presented. (author) [pt

  1. Vitrification of pronuclear-stage mouse embryos on solid surface (SSV) versus in cryotube: comparison of the effect of equilibration time and different sugars in the vitrification solution.

    Science.gov (United States)

    Bagis, H; Sagirkaya, H; Mercan, H Odaman; Dinnyès, A

    2004-02-01

    The cryopreservation of pronuclear-stage embryos has particular importance in transgenic technology and human assisted reproductive technology (ART). The objective of this study was to improve the efficiency of cryopreservation of pronuclear-stage mouse embryos. Two vitrification methods (solid surface vitrification (SSV) vs. vitrification in cryotube) have been compared with special emphasis on the effect of the exposure of the embryos to the solutions for various times and the sugar content (trehalose, sucrose, or raffinose) of the vitrification solutions. Pronuclear-stage embryos were either exposed to 1 M dimethyl sulfoxide (DMSO) + 1 M propylene-glycol (PG) solution for 2, 5, 10, or 15 min or not exposed to this "equilibration" solution. The vitrification solutions consisted of 2.75 M DMSO and 2.75 M PG in M2 medium supplemented with 1 M trehalose (DPT), 1 M sucrose (DPS), or 1 M raffinose (DPR). In the cryotube method, groups of 15-25 embryos were transferred into a 1.8 ml cryotube containing 30 microl of DPT, DPS, or DPR. After 30 sec, the cryotubes were directly plunged into liquid nitrogen (LN(2)) and stored for 1 day to 1 month. Vitrified samples were warmed by immersing the cryotubes in a 40 degrees C water bath and then immediately diluted with 300 microl of 0.3 M trehalose, sucrose, or raffinose in M2. In the SSV method, after equilibration 15-20 embryos were exposed to DPT, DPS, or DPR solutions for around 20 sec before being dropped in 2-microl drops onto a pre-cooled (-150 to -180 degrees C) metal surface. Vitrified droplets were stored in cryovials in LN(2). Warming was performed by transferring the vitrified droplets into 0.3 M solutions of trehalose, sucrose, or raffinose at 37 degrees C, respectively. Results showed that both SSV and cryotube vitrification methods can result in high rates of in vitro blastocyst development (up to 58.3 and 68.5% with DPR, respectively), not statistically different from that of the controls (58.3 and 64.4%). Even

  2. The nasal apparatus of the red squirrel (Sciurus vulgaris L.) embryo at the stage of the fully formed chondrocranium.

    Science.gov (United States)

    Slabý, O

    1991-01-01

    The nasal apparatus of the squirrel embryo at the optimum stage of the chondrocranium displays simple (though not always primitive) features and individual structures developed largely as in other rodents and even in insectivores. Primitive features include the presence of a cartilago paraseptalis communis and probably the simplicity of the olfactory labyrinth, whose main support in the region as a whole is ethmoturbinale I, whose dorsal and ventral lamella divide off the basic recesses; anterior (frontalis), maxillaris and frontoturbinalis. Completely caudally we find ethmoturbinale I, the frontoturbinalia and the relevant secondary (greatly reduced) recesses. The zona annularis is interrupted by failure of the rostral processes of the lamina transversalis anterior (corresponding to the processes laterales ventrales) to fuse with the capsula nasi ant. or with the anlage of the septum nasi. We did find a fenestra nasi superior (lateralis). The atrioturbinale is well developed, the maxilloturbinale only as a trace, but we have a very striking nasoturbinale. In the rostral region of the olfactory segment, the cartilaginous capsule has a very conspicuous thickening, which in this part is formed of paranasal cartilage. The thickening presents outwardly as the prominentia anterior; cavity of the recessus anterior (frontalis) is formed inside it. The rest of the dorsal and caudal wall of this cavity forms the crista semicircularis, which further caudally circumscribes the foramen olfactorium. A foramen epiphaniale is present. The vestibular region of the epithelial nasal tube is interestingly formed. In cross section it is crescent-shaped; the nasal tube itself opens into the convexity, but the lamina transversalis ant. sends a turbinale into the concavity. A cartilago alaris superior, which develops independently in situ, is present; in our stage it is associated with the wall of the capsule, but ventrolaterally it terminates freely and is not joined to any other

  3. Characterization of secreted proteins of 2-cell mouse embryos cultured in vitro to the blastocyst stage with and without protein supplementation.

    Science.gov (United States)

    Burch, Tanya; Yu, Liang; Nyalwidhe, Julius; Horcajadas, Jose A; Bocca, Silvina; Swanson, R James; Oehninger, Sergio

    2014-06-01

    To identify the secreted proteins of murine embryos grown in vitro. Two-cell mouse embryos (n=432) were randomly allocated to culture to the blastocyst stage in protein-free and in protein-supplemented (3 % BSA) media. Proteins were separated by SDS-PAGE; bands were visualized by coomassie staining, followed by in-gel trypsin digestion and liquid chromatography-tandem mass spectrometry. RT-PCR and confocal microscopy were used to confirm gene/protein expression in blastocysts. Of all individually identified proteins, 34 and 23 were found in embryos cultured without and with BSA, respectively, and 20 were common. Identified proteins having an N-terminal secretory sequence or transmembrane domains located on the extracellular backbone were postulated as secreted proteins. Gene and protein expression for two selected molecules were confirmed. Functional analysis revealed over-represented processes related to lipid metabolism, cyclase activity, and cell adhesion/membrane functions. This study provided evidence to further characterize secreted proteins by mouse embryos grown from the 2-cell to the blastocyst stage in vitro. Because of homology between murine and human, these results may provide information to be translated to the clinical setting.

  4. Embryos, microscopes, and society.

    Science.gov (United States)

    Maienschein, Jane

    2016-06-01

    Embryos have different meanings for different people and in different contexts. Seen under the microscope, the biological embryo starts out as one cell and then becomes a bunch of cells. Gradually these divide and differentiate to make up the embryo, which in humans becomes a fetus at eight weeks, and then eventually a baby. At least, that happens in those cases that carry through normally and successfully. Yet a popular public perception imagines the embryo as already a little person in the very earliest stages of development, as if it were predictably to become an adult. In actuality, cells can combine, pull apart, and recombine in a variety of ways and still produce embryos, whereas most embryos never develop into adults at all. Biological embryos and popular imaginations of embryos diverge. This paper looks at some of the historical reasons for and social implications of that divergence. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

  5. Interpretation of recovery stage III in gold. [Electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Seeger, A.; Frank, W. (Max-Planck-Institut fuer Metallforschung, Stuttgart (Germany, F.R.). Inst. fuer Physik; Stuttgart Univ. (Germany, F.R.). Inst. fuer Theoretische und Angewandte Physik)

    1983-05-01

    The paper compares a recent investigation of Stage-III recovery on electron-irradiated gold by Sonnenberg and Dedek with earlier work on cold-worked or quenched gold. The experimental results of Sonnenberg and Dedek are found to be in excellent agreement with those of Schuele, Seeger, Schumacher, and King, who showed that in Au Stage III is due to the migration of an elementary intrinsic point defect with migration enthalpy Hsup(III) = (0.71 +- 0.02)eV. Since the monovacancy migration enthalpy Hsub(IVsup(M)) = (0.83 +- 0.02)eV obtained by Schuele et al. has been confirmed by other workers and independent techniques, it is concluded that Hsup(III) represents the migration enthalpy of isolated self-interstitials.

  6. Intra- and interobserver analysis in the morphological assessment of early stage embryos during an IVF procedure: a multicentre study

    Directory of Open Access Journals (Sweden)

    Devroe Johanna

    2011-09-01

    Full Text Available Abstract Background Quality control programs are necessary to maintain good clinical practice. Embryo grading has been described as one of the external quality assurance schemes. Although the evaluation of embryos is based on the assessment of morphological characteristics, considerable intra- and inter-observer variability has been described. In this multicentre study, the variability in the embryo evaluation has been evaluated using morphological characteristics on day 1, day 2 and day 3 of embryo development. Methods Five embryologists of four different IVF centers participated in this study. Multilevel images of embryos were presented on a website at different time points to evaluate intra-and inter-observer agreement in the assessment of embryo morphology. The embryos were evaluated on day 1, day 2 and day 3 of their development and each embryologist had to decide if the embryo had to be transferred, cryopreserved or discarded. Results Both intra-observer agreement and inter-observer agreement were good to excellent for the position of the pronuclei on day 1, the number of blastomeres on day 2 and day 3 and the clinical decision (transfer, cryopreservation, discard. For all other characteristics (size of pronuclei, presence of cytoplasomic halo, degree of fragmentation and size of blastomeres the intra- and inter-observer agreement was moderate to very poor. Conclusions Mono- or multicentre quality control on embryo scoring by morphological assessment can easily be performed through the design of a simple website. In the future the website design can be adapted to generate statistical feedback upon scoring and can even include a training module.

  7. Acetylcholinesterase-positive innervation is present at undifferentiated stages of the sea turtle Lepidochelis olivacea embryo gonads: implications for temperature-dependent sex determination.

    Science.gov (United States)

    Gutiérrez-Ospina, G; Jiménez-Trejo, F J; Favila, R; Moreno-Mendoza, N A; Granados Rojas, L; Barrios, F A; Díaz-Cintra, S; Merchant-Larios, H

    1999-07-19

    In embryos of different reptile species, incubation temperature triggers a cascade of endocrine events that lead to gonad sex differentiation. The cellular and molecular mechanisms by which temperature sets in motion this process are still controversial. Here, we begin evaluating the possible participation of the nervous system in temperature-dependent sex determination by showing the existence and origin of acetylcholinesterase (AchE)-positive nerve fibers in undifferentiated gonads of the Lepidochelys olivacea (L. olivacea) sea turtle putative male and female embryos, along the thermosensitive period for sex determination (TPSD; stages 20-27). AChE-positive nerve bundles and fibers were readily visualized until developmental stage 24 and thereafter. DiI injections and confocal imaging showed that some of these gonadal nerves arise from the lower thoracic and upper lumbar spinal cord levels, and might thus be sensory in nature. Because the vertebrate spinal cord is capable of integrating by itself thermoregulatory responses with no intervention of uppermost levels of the central nervous system, we also evaluated spinal cord maturation during the TPSD. The maturation of the spinal cord was more advanced in putative female than in male embryos, when sex determination is taking place for each sex; this process starts and ends earlier in male than in female embryos. Together these observations open the possibility that the spinal cord and the innervation derived from it could play a direct role in driving or modulating the process of temperature-dependent gonad sex determination and/or differentiation, particularly in female L. olivacea embryos.

  8. Genome-Wide DNA Methylation Patterns of Bovine Blastocysts Developed In Vivo from Embryos Completed Different Stages of Development In Vitro.

    Directory of Open Access Journals (Sweden)

    Dessie Salilew-Wondim

    Full Text Available Early embryonic loss and altered gene expression in in vitro produced blastocysts are believed to be partly caused by aberrant DNA methylation. However, specific embryonic stage which is sensitive to in vitro culture conditions to alter the DNA methylation profile of the resulting blastocysts remained unclear. Therefore, the aim of this study was to investigate the stage specific effect of in vitro culture environment on the DNA methylation response of the resulting blastocysts. For this, embryos cultured in vitro until zygote (ZY, 4-cell (4C or 16-cell (16C were transferred to recipients and the blastocysts were recovery at day 7 of the estrous cycle. Another embryo group was cultured in vitro until blastocyst stage (IVP. Genome-wide DNA methylation profiles of ZY, 4C, 16C and IVP blastocyst groups were then determined with reference to blastocysts developed completely under in vivo condition (VO using EmbryoGENE DNA Methylation Array. To assess the contribution of methylation changes on gene expression patterns, the DNA methylation data was superimposed to the transcriptome profile data. The degree of DNA methylation dysregulation in the promoter and/or gene body regions of the resulting blastocysts was correlated with successive stages of development the embryos advanced under in vitro culture before transfer to the in vivo condition. Genomic enrichment analysis revealed that in 4C and 16C blastocyst groups, hypermethylated loci were outpacing the hypomethylated ones in intronic, exonic, promoter and proximal promoter regions, whereas the reverse was observed in ZY blastocyst group. However, in the IVP group, as much hypermethylated as hypomethylated probes were detected in gene body and promoter regions. In addition, gene ontology analysis indicated that differentially methylated regions were found to affected several biological functions including ATP binding in the ZY group, programmed cell death in the 4C, glycolysis in 16C and genetic

  9. The First Human Cloned Embryo.

    Science.gov (United States)

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  10. Electron microscope study of the genesis of strain-induced martensite embryos

    International Nuclear Information System (INIS)

    Staudhammer, K.P.; Hecker, S.S.; Murr, L.E.

    1984-01-01

    Previous work of Olson and Cohen and Murr, et al., is used to describe the genesis of martensite embryos which form at the intersection of microscopic shear bands in deformed type 304 stainless steel. It is shown that the intersection volume included within intersecting shear bands contains irregular and smaller dispersed volume segments forming α' martensite (bcc). These correspond to the satisfaction of specific intersections of stacking faults or partial dislocations on approximately every second (111)/sub fcc/ plane in one direction, and every third (111)/sub fcc/ plane in the other (conjugate) direction. The requisite stacking fault or partial dislocation arrangements are produced in an irregular fashion resulting in α' martensite embryos nucleating in an incomplete and irregular fashion within the intersection volume. 9 references, 2 figures

  11. Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Yan; Liu, Chunying; Lu, Wenwen; Zhang, Quan; Sodmergen, E-mail: sodmergn@pku.edu.cn

    2016-05-27

    The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysis revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.

  12. Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

    International Nuclear Information System (INIS)

    Ju, Yan; Liu, Chunying; Lu, Wenwen; Zhang, Quan; Sodmergen

    2016-01-01

    The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysis revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.

  13. Embryo splitting

    OpenAIRE

    Karl Illmensee; Mike Levanduski

    2010-01-01

    Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board appr...

  14. The developmental stage of chicken embryos modulates the impact of in ovo olfactory stimulation on food preferences.

    Science.gov (United States)

    Bertin, Aline; Calandreau, Ludovic; Arnould, Cécile; Lévy, Frédéric

    2012-03-01

    Like mammals, bird embryos are capable of chemosensory learning, but the ontogeny of their feeding preferences has not been examined. We tested if the timing of stimulation in chicken embryos modulates the impact of in ovo olfactory stimulation on later food preferences. We exposed chicken embryos to an olfactory stimulus for a 4-day period in the middle or toward the end of the incubation period. The chicks were tested for their preference between foods with and without the olfactory stimulus in 3-min choice tests and on a 24-h time scale. Regardless of the type of food (familiar or novel) or the duration of the test, the control chicks not exposed to the olfactory stimulus consistently showed significant preferences for non-odorized foods. Chicks that were exposed in ovo to the olfactory stimulus did not show a preference for odorized or non-odorized foods. Only those chicks that were exposed to the olfactory stimulus toward the end of the incubation period differed from the controls and incorporated a higher proportion of odorized food into their diets on a 24-h time scale. This result indicates that olfactory stimulation at the end of embryonic development has a stronger impact on later feeding preferences. Our findings contribute to the growing pool of recent data appreciating the impact of olfactory signals on behavior regulation in avian species.

  15. Urochordate ascidians possess a single isoform of Aurora kinase that localizes to the midbody via TPX2 in eggs and cleavage stage embryos.

    Directory of Open Access Journals (Sweden)

    Celine Hebras

    Full Text Available Aurora kinases are key proteins found throughout the eukaryotes that control mitotic progression. Vertebrate Aurora-A and B kinases are thought to have evolved from a single Aurora-kinase isoform closest to that found in present day urochordates. In urochordate ascidians Aurora binds both TPX2 (a vertebrate AURKA partner and INCENP (a vertebrate AURKB partner and localizes to centrosomes and spindle microtubules as well as chromosomes and midbody during both meiosis and mitosis. Ascidian Aurora also displays this localization pattern during mitosis in echinoderms, strengthening the idea that non-vertebrate deuterostomes such as the urochordates and echinoderms possess a single form of Aurora kinase that has properties of vertebrate Aurora-kinase A and B. In the ascidian, TPX2 localizes to the centrosome and the spindle poles also as in vertebrates. However, we were surprised to find that TPX2 also localized strongly to the midbody in ascidian eggs and embryos. We thus examined more closely Aurora localization to the midbody by creating two separate point mutations of ascidian Aurora predicted to perturb binding to TPX2. Both forms of mutated Aurora behaved as predicted: neither localized to spindle poles where TPX2 is enriched. Interestingly, neither form of mutated Aurora localized to the midbody where TPX2 is also enriched, suggesting that ascidian Aurora midbody localization required TPX2 binding in ascidians. Functional analysis revealed that inhibition of Aurora kinase with a pharmacological inhibitor or with a dominant negative kinase dead form of Aurora caused cytokinesis failure and perturbed midbody formation during polar body extrusion. Our data support the view that vertebrate Aurora-A and B kinases evolved from a single non-vertebrate deuterostome ancestor. Moreover, since TPX2 localizes to the midbody in ascidian eggs and cleavage stage embryos it may be worthwhile re-assessing whether Aurora A kinase or TPX2 localize to the midbody

  16. Expression pattern of pluripotent markers in different embryonic developmental stages of buffalo (Bubalus bubalis) embryos and putative embryonic stem cells generated by parthenogenetic activation.

    Science.gov (United States)

    Singh, Karn P; Kaushik, Ramakant; Garg, Veena; Sharma, Ruchi; George, Aman; Singh, Manoj K; Manik, Radhey S; Palta, Prabhat; Singla, Suresh K; Chauhan, Manmohan S

    2012-12-01

    In this study, we describe the production of buffalo parthenogenetic blastocysts and subsequent isolation of parthenogenetic embryonic stem cell (PGESC)-like cells. PGESC colonies exhibited dome-shaped morphology and were clearly distinguishable from the feeder layer cells. Different stages of development of parthenogenetic embryos and derived embryonic stem cell (ESC)-like cells expressed key ESC-specific markers, including OCT-4, NANOG, SOX-2, FOXD3, REX-1, STAT-3, TELOMERASE, NUCLEOSTEMIN, and cMYC. Immunofluorescence-based studies revealed that the PGESCs were positive for surface-based pluripotent markers, viz., SSEA-3, SSEA-4, TRA 1-80, TRA 1-60, CD-9, and CD-90 and exhibited high alkaline phosphatase (ALP) activity. PGEC cell-like cells formed embryoid body (EB)-like structures in hanging drop cultures and when cultured for extended period of time spontaneously differentiated into derivatives of three embryonic germ layers as confirmed by RT-PCR for ectodermal (CYTOKERATIN8, NF-68), mesodermal (MSX1, BMP-4, ASA), and endodermal markers (AFP, HNF-4, GATA-4). Differentiation of PGESCs toward the neuronal lineage was successfully directed by supplementation of serum-containing media with retinoic acid. Our results indicate that the isolated ESC-like cells from parthenogenetic blastocyst hold properties of ESCs and express markers of pluripotency. The pluripotency markers were also expressed by early cleavage-stage of buffalo embryos.

  17. Scanning electron microscopy of surface features of hamster embryo cells transformed in vitro by x-irradiation

    International Nuclear Information System (INIS)

    Borek, C.; Fenoglio, C.M.

    1976-01-01

    Scanning electron microscope studies were carried out on Syrian hamster embryo cells transformed in vitro by x-irradiation (300 rads) (x-ray transformed) and on normal nonirradiated and irradiated nontransformed controls. Transformed cells appeared in scanning electron microscopy as pleomorphic, thick cells piling up over each other and exhibiting extensive surface features consisting of microvilli, blebs, and ruffles. These surface structures were seen on single as well as on densely cultured transformed cells during both interphase and mitosis. The complex surface was observed shortly after transformation (on cells of a 20-day-old clone) and seems a permanent feature of the x-ray transformed cells (present after 8 years in culture). All controls appeared by scanning electron microscopy as regular, flat, and smooth cells which grew in high-density cultures to seemingly contact-inhibited monolayers. During mitosis the normal cells (control, nontransformed) displayed surface excrescences similar to those of the transformed cells making the mitotic normal cells indistinguishable from transformed cells. The complex surface features in the normal cells were temporary and reversed back to characteristic smoothness upon reentrance into interphase

  18. Apparatus and methods for controlling electron microscope stages

    Science.gov (United States)

    Duden, Thomas

    2015-08-11

    Methods and apparatus for generating an image of a specimen with a microscope (e.g., TEM) are disclosed. In one aspect, the microscope may generally include a beam generator, a stage, a detector, and an image generator. A plurality of crystal parameters, which describe a plurality of properties of a crystal sample, are received. In a display associated with the microscope, an interactive control sphere based at least in part on the received crystal parameters and that is rotatable by a user to different sphere orientations is presented. The sphere includes a plurality of stage coordinates that correspond to a plurality of positions of the stage and a plurality of crystallographic pole coordinates that correspond to a plurality of polar orientations of the crystal sample. Movement of the sphere causes movement of the stage, wherein the stage coordinates move in conjunction with the crystallographic coordinates represented by pole positions so as to show a relationship between stage positions and the pole positions.

  19. The action of X-rays on electrophysiological characteristics in early stages of development of frog embryo

    International Nuclear Information System (INIS)

    Tevdoradze, V.V.; Nadarejshvili, K.Sh.

    1987-01-01

    Comparative investigation of dynamics of changes in the membrane potential (MP), input resistance (R in ) and the coefficient of electric coupling (K ec ) between blastomers in the process of the first divisions of irradiated and nonirradiated Rana ridibunda frog embryo cleavage is carried out. Microelectrophysiological equipment has been used. It is detected that 12 Gy radiation dose does not change cycling of changes and absolute MP and K ec while the amplitute of cyclic oscillations (R in ) decreases sharpy. Possible mechanisms of this effect and perspectives of investigation of certain general problems on radiation membranology are discussed

  20. NASAwide electronic publishing system: Prototype STI electronic document distribution, stage-4 evaluation report

    Science.gov (United States)

    Tuey, Richard C.; Collins, Mary; Caswell, Pamela; Haynes, Bob; Nelson, Michael L.; Holm, Jeanne; Buquo, Lynn; Tingle, Annette; Cooper, Bill; Stiltner, Roy

    1996-01-01

    This evaluation report contains an introduction, seven chapters, and five appendices. The Introduction describes the purpose, conceptual frame work, functional description, and technical report server of the STI Electronic Document Distribution (EDD) project. Chapter 1 documents the results of the prototype STI EDD in actual operation. Chapter 2 documents each NASA center's post processing publication processes. Chapter 3 documents each center's STI software, hardware, and communications configurations. Chapter 7 documents STI EDD policy, practices, and procedures. The appendices, which arc contained in Part 2 of this document, consist of (1) STI EDD Project Plan, (2) Team members, (3) Phasing Schedules, (4) Accessing On-line Reports, and (5) Creating an HTML File and Setting Up an xTRS. In summary, Stage 4 of the NASAwide Electronic Publishing System is the final phase of its implementation through the prototyping and gradual integration of each NASA center's electronic printing systems, desktop publishing systems, and technical report servers to be able to provide to NASA's engineers, researchers, scientists, and external users the widest practicable and appropriate dissemination of information concerning its activities and the result thereof to their work stations.

  1. Single-stage unity power factor based electronic ballast

    Indian Academy of Sciences (India)

    This paper deals with the design, modeling, analysis and implementation of unity power factor (UPF) based electronic ballast for a fluorescent lamp (FL). The proposed electronic ballast uses a boost AC–DC converter as a power factor corrector (PFC) to improve the power quality at the input ac mains. In this singlestage ...

  2. Stem Cell Differentiation Stage Factors from Zebrafish Embryo: A Novel Strategy to Modulate the Fate of Normal and Pathological Human (Stem) Cells.

    Science.gov (United States)

    Biava, Pier M; Canaider, Silvia; Facchin, Federica; Bianconi, Eva; Ljungberg, Liza; Rotilio, Domenico; Burigana, Fabio; Ventura, Carlo

    2015-01-01

    In spite of the growing body of evidence on the biology of the Zebrafish embryo and stem cells, including the use of Stem Cell Differentiation Stage Factors (SCDSFs) taken from Zebrafish embryo to impact cancer cell dynamics, comparatively little is known about the possibility to use these factors to modulate the homeostasis of normal human stem cells or to modulate the behavior of cells involved in different pathological conditions. In the present review we recall in a synthetic way the most important researches about the use of SCDSFs in reprogramming cancer cells and in modulating the high speed of multiplication of keratinocytes which is characteristic of some pathological diseases like psoriasis. Moreover we add here the results about the capability of SCDSFs in modulating the homeostasis of human adiposederived stem cells (hASCs) isolated from a fat tissue obtained with a novel-non enzymatic method and device. In addition we report the data not yet published about a first protein analysis of the SCDSFs and about their role in a pathological condition like neurodegeneration.

  3. 77 FR 53967 - Medicare and Medicaid Programs; Electronic Health Record Incentive Program-Stage 2

    Science.gov (United States)

    2012-09-04

    ... objective in Stage 2, and the ``Provide patients with an electronic copy of their health information...-designated transmission method. For EPs, this includes an aggregate electronic submission or a patient-level... eligible hospitals and CAHs, this includes an aggregate electronic submission or a patient-level data...

  4. Staged electron laser accelerator (STELLA) experiment at brookhaven ATF

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelsky, I.V.; Steenbergen, A. van; Gallardo, J.C. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1998-03-01

    The STELLA experiment is being prepared at the BNL Accelerator Test Facility (STF). The goal of the experiment is to demonstrate quasi-monochromatic inverse Cherenkov acceleration (ICA) of electrons bunched to the laser wavelength period. Microbunches on the order of 2 {mu}m in length separated by 10.6 {mu}m will be produced using an inverse free electron laser (IFEL) accelerator driven by a CO{sub 2} laser. The design and simulations for two phases of this experiment including demonstration of 10 MeV and 100 MeV acceleration are presented. (author)

  5. A Thermoelectric Generation System and Its Power Electronics Stage

    DEFF Research Database (Denmark)

    Gao, Junling; Sun, Kai; Ni, Longxian

    2012-01-01

    the feasibility and effectiveness of the proposed design. Finally, the thermal–electric coupling effects caused by current-related heat source terms, such as the Peltier effect etc., are reported and discussed, and the potential influence on the power electronics design due to such coupling is analyzed....

  6. Ultrastructural analyses of somatic embryo initiation, development and polarity establishment from mesophyll cells of Dactylis glomerata

    Science.gov (United States)

    Vasilenko, A.; McDaniel, J. K.; Conger, B. V.

    2000-01-01

    Somatic embryos initiate and develop directly from single mesophyll cells in in vitro-cultured leaf segments of orchardgrass (Dactylis glomerata L.). Embryogenic cells establish themselves in the predivision stage by formation of thicker cell walls and dense cytoplasm. Electron microscopy observations for embryos ranging from the pre-cell-division stage to 20-cell proembryos confirm previous light microscopy studies showing a single cell origin. They also confirm that the first division is predominantly periclinal and that this division plane is important in establishing embryo polarity and in determining the embryo axis. If the first division is anticlinal or if divisions are in random planes after the first division, divisions may not continue to produce an embryo. This result may produce an embryogenic cell mass, callus formation, or no structure at all. Grant numbers: NAGW-3141, NAG10-0221.

  7. Trains of electron pulses generation using multi-stage cavities

    International Nuclear Information System (INIS)

    Kamada, Masaki; Mori, Michiya; Sugawara, Kazuyoshi; Yamada, Yoko; Kurihara, Kazuteru; Shirasaka, Haruki; Nishiguchi, Takashi; Ando, Ritoku; Kamada, Keiichi

    2002-01-01

    Automodulation of an intense relativistic electron beam was reexamined experimentally to obtain trains of subnanosecond electron bunches. Sufficient beam modulation with frequency larger than 1 GHz was expected for the trains of subnanosecond bunches. It was obtained when a short pulse electron beam with energy of 550 keV, current of 4 kA, pulse duration of 12 ns and current rise time of 2ns was injected to a series of four coaxial cavities with the length of 75 mm. However, only a poor modulation was observed when a long pulse electron beam of 700 keV, 4 kA, 175 ns with current rise time of 20 ns was injected to the same cavities. Transmission line theory as well PIC code simulation suggested that the round trip time for the electromagnetic wave in the cavity must be longer than the rise time of the beam current to obtain the high level current modulation. Therefore, we studied experimentally how the ratio between the beam current rise time and the length of the cavity affects on the level of current modulation. Single cavity experiments were carried out with the short pulse beam. Single cavity with the length of 75, 150 or 300 mm was utilized. The round trip times for 75 and 150 mm cavities are shorter than the current rise time of 2 ns. The experiments with a 75 or 150 mm cavity resulted in suppression of the modulation amplitude. In the case of a 300 mm cavity, the high level modulation was obtained. The simulation results showed good agreements with the experimental results. We employed a series of cavities with decreasing lengths to improve the current rise time. For the short pulse beam, the high level current 1 GHz modulation was obtained when two 75 mm cavities were set at the downstream side of cavities with lengths of 300 mm and 150 mm. (author)

  8. Manipulating early pig embryos.

    Science.gov (United States)

    Niemann, H; Reichelt, B

    1993-01-01

    On the basis of established surgical procedures for embryo recovery and transfer, the early pig embryo can be subjected to various manipulations aimed at a long-term preservation of genetic material, the generation of identical multiplets, the early determination of sex or the alteration of the genetic make-up. Most of these procedures are still at an experimental stage and despite recent considerable progress are far from practical application. Normal piglets have been obtained after cryopreservation of pig blastocysts hatched in vitro, whereas all attempts to freeze embryos with intact zona pellucida have been unsuccessful. Pig embryos at the morula and blastocyst stage can be bisected microsurgically and the resulting demi-embryos possess a high developmental potential in vitro, whereas their development in vivo is impaired. Pregnancy rates are similar (80%) but litter size is reduced compared with intact embryos and twinning rate is approximately 2%. Pig blastomeres isolated from embryos up to the 16-cell stage can be grown in culture and result in normal blastocysts. Normal piglets have been born upon transfer of blastocysts derived from isolated eight-cell blastomeres, clearly underlining the totipotency of this developmental stage. Upon nuclear transfer the developmental capacity of reconstituted pig embryos is low and culture. Sex determination can be achieved either by separation of X and Y chromosome bearing spermatozoa by flow cytometry or by analysing the expression of the HY antigen in pig embryos from the eight-cell to morula stage. Microinjection of foreign DNA has been successfully used to alter growth and development of transgenic pigs, and to produce foreign proteins in the mammary gland or in the bloodstream, indicating that pigs can be used as donors for valuable human pharmaceutical proteins. Another promising area of gene transfer is the increase of disease resistance in transgenic lines of pigs. Approximately 30% of pig spermatozoa bind

  9. Optimizing the number of cleavage stage embryos to transfer on day 3 in women 38 years of age and older: a Society for Assisted Reproductive Technology database study.

    Science.gov (United States)

    Stern, Judy E; Goldman, Marlene B; Hatasaka, Harry; MacKenzie, Todd A; Surrey, Eric S; Racowsky, Catherine

    2009-03-01

    To determine the optimal number of day 3 embryos to transfer in women >or=38 years by conducting an evidence-based evaluation. Retrospective analysis of 2000-2004 national SART data. National writing group. A total of 36,103 day 3 embryo transfers in women >or=38 years undergoing their first assisted reproductive technology cycle. None. Logistic regression was used to model the probability of pregnancy, delivery, and multiple births (twin or high order) based on age- and cycle-specific parameters. Pregnancy rates, delivery rates, and multiple rates increased up to transfer of three embryos in 38-year-olds and four in 39-year-olds; beyond this number, only multiple rates increased. In women >or=40 years, delivery rates and multiple rates climbed steadily with increasing numbers transferred. Multivariate analysis confirmed the statistically significant effect of age, number of oocytes retrieved, and embryo cryopreservation on delivery and multiple rates. Maximum FSH level was not an independent predictor by multivariate analysis. Use of intracytoplasmic sperm injection was associated with lowered delivery rate. No more than three or four embryos should be transferred in 38- and 39-year-olds, respectively, whereas up to five embryos could be transferred in >or=40-year-olds. Numbers of embryos to transfer should be adjusted according to number of oocytes retrieved and availability of excess embryos for cryopreservation.

  10. Effect of vitamin A supplementation at different gaseous environments on in vitro development of pre-implantation sheep embryos to the blastocyst stage.

    Science.gov (United States)

    Rajesh, N; Shankar, M B; Deecaraman, M

    2010-11-01

    Vitamin A (all-trans retinol) is an important antioxidant whose role in embryo development in vitro and in vivo is well established. Oxidative stress is a major cause of defective embryo development. This study evaluated the effects of all-trans retinol supplementation to maturation and embryo culture media under different gaseous environments on the development of ovine oocytes and embryos in vitro. The percentages of cleavage, morula and blastocyst, total cell count and comet assay were taken as indicators of developmental competence of embryos. In experiments I and II, all-trans retinol at concentrations of 0, 2, 4, 6, 8 and 10 μM were supplemented to the oocyte maturation medium and cultured in an environment of 5% or 20% O2 respectively. All-trans retinol supplementation (6 μM) to the maturation medium at 5% O2 levels significantly increased blastocyst yield and total cell number (P embryo culture media under a 5% or 20% O2 environment, respectively. All-trans retinol supplementation to the embryo culture medium at 5% O2 levels did not yield any significant result whereas the culture at 20% O2 levels gave significantly higher blastocyst yield in the 6 μM supplemented group compared with the control group (P < 0.01).

  11. ESTÁDIOS DE DESENVOLVIMENTO DE EMBRIÕES NA OBTENÇÃO DE PLANTAS EM CRUZAMENTOS ENTRE GENITORES APIRENOS DE VIDEIRA EMBRYO GROWTH STAGES ON PLANT OBTENTION FROM CROSSES BETWEEN SEEDLESS GRAPE PARENTS

    Directory of Open Access Journals (Sweden)

    ADRIANE LEITE DO AMARAL

    2001-12-01

    Full Text Available Pesquisou-se o efeito do estádio de desenvolvimento de embriões resgatados na obtenção de plantas em cruzamentos entre genitores apirenos de videira, utilizando dois métodos de cultivo in vitro de sementes-traço. No método 1 (M1, as sementes-traço foram cultivadas 60 dias em meio-de-cultura ER e no método 2 (M2 60 dias em ER, mais 30 dias em meio-de-cultura MS. O estádio de desenvolvimento do embrião foi identificado no final destes períodos, quando do resgate e transferência para meio-de-cultura WP. Quatro tipos de embriões foram identificados: globular, cordiforme, torpedo e indefinido. O estádio globular foi encontrado com maior freqüência, levando à obtenção de maior número de plantas, mesmo tendo apresentado menor capacidade de gerar plantas. A maior eficiência em gerar plantas foi obtida com o estádio torpedo. No M2, ocorreu maior número de embriões germinados e de plantas desenvolvidas. Como o estádio de desenvolvimento do embrião influencia na obtenção de plantas, o resgate de embriões em estádio mais avançado do seu desenvolvimento leva a tem maior capacidade de gerar plantas. Portanto, uso de técnicas que favoreçam o resgate de embriões mais desenvolvidos pode aumentar o número de plantas obtidas.It was investigated the effect of the growth stage of rescued embryos on plant obtention from crosses between seedless grape parents. Two methods for in vitro culture were compared. Method 1 (M1: seed traces were cultured 60 days in ER culture medium. Method 2 (M2: procedure of M1 followed by additional 30 days in MS culture medium. The stage of embryo growth was established at the end of this period, when the embryos were rescued and transfered to WP culture medium. Four classes of embryo stages were indentified: globular, heart, torpedo and undefined. The globular stage, the most frequently found, produced the largest quantity of recovered plants, though it had the lowest capacity of originating plants

  12. Rabbit whole embryo culture.

    Science.gov (United States)

    Marshall, Valerie A; Carney, Edward W

    2012-01-01

    Although the rabbit is used extensively in developmental toxicity testing, relatively little is known about the fundamental developmental biology of this species let alone mechanisms underlying developmental toxicity. This paucity of information about the rabbit is partly due to the historic lack of whole embryo culture (WEC) methods for the rabbit, which have only been made available fairly recently. In rabbit WEC, early somite stage embryos (gestation day 9) enclosed within an intact amnion and attached to the visceral yolk sac are dissected from maternal tissues and placed in culture for up to 48 h at approximately 37°C and are continuously exposed to an humidified gas atmosphere mixture in a rotating culture system. During this 48 h culture period, major phases of organogenesis can be studied including cardiac looping and segmentation, neural tube closure, and development of anlagen of the otic system, eyes and craniofacial structures, somites and early phases of limb development (up to bud stage), as well as expansion and closure of the visceral yolk sac around the embryo. Following completion of the culture period, embryos are evaluated based on several growth and development parameters and also are assessed for morphological abnormalities. The ability to sustain embryo development independent of the maternal system allows for exposure at precise development stages providing the opportunity study the direct action of a teratogen or one of its metabolites on the developing embryo. Rabbit WEC is perhaps most useful when used in conjunction with rodent WEC methods to investigate species-specific mechanisms of developmental toxicity.

  13. Evidence for stage-specific modulation of specific microRNAs (miRNAs) and miRNA processing components in zygotic embryo and female gametophyte of loblolly pine (Pinus taeda).

    Science.gov (United States)

    Oh, Thomas J; Wartell, Roger M; Cairney, John; Pullman, Gerald S

    2008-01-01

    MicroRNAs (miRNAs) are known to regulate plant development, but have not been studied in gymnosperm seed tissues. The presence and characteristics of several miRNAs were examined in zygotic embryos (ZEs) and female gametophytes (FGs) of Pinus taeda (loblolly pine). Evidence for miRNAs was obtained using northern analyses and quantitative reverse transcription polymerase chain reaction (qRT-PCR) mediated with poly(A) polymerase. Partial sequences of two miRNAs were verified. Three regions of putative mRNA targets were analyzed by qRT-PCR to monitor the occurrence of stage-dependent miRNA-mediated cleavage. Five miRNAs were identified in ZEs and FGs along with partial sequences of Pta-miR166 and Pta-miR167. Both miRNAs showed differing degrees of tissue-specific and stage-specific modulation. Analysis of HB15L mRNA (a potential Pta-miR166 target) suggested miRNA-guided cleavage in ZEs and FGs. Analysis of ARF8L mRNA (a potential Pta-miR167 target) implied cleavage in ZEs but not in FGs. Argonaute9-like mRNA (ptAGO9L) showed stage-specific modulation of expression in ZEs that appeared to be inverted in the corresponding FGs. MicroRNAs and argonaute genes varied spatiotemporally during seed development. The peak levels of Pta-miR166 in FGs and ptAGO9L in embryos occurred at stage 9.1, a critical transition point during embryo development and a point where somatic embryo maturation often stops. MicroRNAs identified in FG tissue may play a role in embryogenesis.

  14. High-power free-electron laser amplifier using a scalloped electron beam and a two-stage wiggler

    Directory of Open Access Journals (Sweden)

    D. C. Nguyen

    2006-05-01

    Full Text Available High-power free-electron laser (FEL amplifiers present many practical design and construction problems. One such problem is possible damage to any optical beam control elements beyond the wiggler. The ability to increase the optical beam’s divergence angle after the wiggler, thereby reducing the intensity on the first optical element, is important to minimize such damage. One proposal to accomplish this optical beam spreading is to pinch the electron beam thereby focusing the radiation as well. In this paper, we analyze an approach that relies on the natural betatron motion to pinch the electron beam near the end of the wiggler. We also consider a step-tapered, two-stage wiggler to enhance the efficiency. The combination of a pinched electron beam and step-taper wiggler leads to additional optical guiding of the optical beam. This novel configuration is studied in simulation using the MEDUSA code. For a representative set of beam and wiggler parameters, we discuss (i the effect of the scalloped beam on the interaction in the FEL and on the focusing and propagation of the radiation, and (ii the efficiency enhancement in the two-stage wiggler.

  15. Cryopreservation of green fluorescent protein (GFP)-labeled primordial germ cells with GFP fused to the 3' untranslated region of the nanos gene by vitrification of Japanese eel (Anguilla japonica) somite stage embryos.

    Science.gov (United States)

    Kawakami, Y; Ishihara, M; Saito, T; Fujimoto, T; Adachi, S; Arai, K; Yamaha, E

    2012-12-01

    Primordial germ cells (PGC) are the only cell type in developing embryos with the potential to transmit genetic information to the next generation. In this study, PGC of Japanese eel (Anguilla japonica) were visualized by injection of mRNA synthesized from a construct carrying the green fluorescent protein (GFP) gene fused to the 3' untranslated region of the Japanese eel nanos gene. We investigated the feasibility of cryopreserving Japanese eel PGC by vitrification of dechorionated whole somite stage embryos. The GFP-labeled PGC were rapidly cooled using liquid nitrogen after exposure to a pretreatment solution containing 1.5 M cryoprotectant (methanol, dimethyl sulfoxide, and glycerol for 10 min and ethylene glycol for 10, 20, and 30 min) and a vitrification solution containing 3 M cryoprotectant and 0.5 M sucrose for 1, 5, and 10 min. Ethylene glycerol is an effective cryoprotectant for embryonic cells and shows no evidence of ice formation after thawing. Vitrified and thawed PGC were transplanted into blastula stage embryos from zebrafish (Danio rerio). The GFP-labeled PGC migrated toward the host gonadal ridge, suggesting maintenance of their normal migration motility. These techniques may assist in achieving inter- and intraspecies germ-line chimers using donor Japanese eel PGC.

  16. In vitro culture of Arabidopsis embryos.

    Science.gov (United States)

    Sauer, Michael; Friml, Jirí

    2008-01-01

    Embryogenesis of Arabidopsis thaliana follows a nearly invariant cell division pattern and provides an ideal system for studies of early plant development. However, experimental manipulation with embryogenesis is difficult, as the embryo develops deeply inside maternal tissues. Here, we present a method to culture zygotic Arabidopsis embryos in vitro. It enables culturing for prolonged periods of time from the first developmental stages on. The technique omits excision of the embryo by culturing the entire ovule, which facilitates the manual procedure. It allows pharmacological manipulation of embryo development and does not interfere with standard techniques for localizing gene expression and protein localization in the cultivated embryos.

  17. Investigation of the aluminium-aluminium oxide reversible transformation as observed by hot stage electron microscopy.

    Science.gov (United States)

    Grove, C. A.; Judd, G.; Ansell, G. S.

    1972-01-01

    Thin foils of high purity aluminium and an Al-Al2O3 SAP type of alloy were oxidised in a specially designed hot stage specimen chamber in an electron microscope. Below 450 C, amorphous aluminium oxide formed on the foil surface and was first detectable at foil edges, holes, and pits. Islands of aluminium then nucleated in this amorphous oxide. The aluminium islands displayed either a lateral growth with eventual coalescence with other islands, or a reoxidation process which caused the islands to disappear. The aluminium island formation was determined to be related to the presence of the electron beam. A mechanism based upon electron charging due to the electron beam was proposed to explain the nucleation, growth, coalescence, disappearance, and geometry of the aluminium islands.

  18. NASA wide electronic publishing system: Electronic printing and duplicating. Stage 3 evaluation report

    Science.gov (United States)

    Tuey, Richard C.; Moore, Fred W.; Ryan, Christine A.

    1995-01-01

    The report is presented in four sections: The Introduction describes the duplicating configuration under evaluation and the Background contains a chronological description of the evaluation segmented by phases 1 and 2. This section includes the evaluation schedule, printing and duplicating requirements, storage and communication requirements, electronic publishing system configuration, existing processes and proposed processes, billing rates, costs and productivity analysis, and the return on investment based upon the data gathered to date. The third section contains the phase 1 comparative cost and productivity analysis. This analysis demonstrated that LaRC should proceed with a 90-day evaluation of the DocuTech and follow with a phase 2 cycle to actually demonstrate that the proposed system would meet the needs of LaRC's printing and duplicating requirements, benchmark results, cost comparisons, benchmark observations, and recommendations. These are documented after the recommendations.

  19. Development of interspecies cloned embryos in yak and dog.

    Science.gov (United States)

    Murakami, Masao; Otoi, Takeshige; Wongsrikeao, Pimprapar; Agung, Budiyanto; Sambuu, Rentsenkhand; Suzuki, Tatsuyuki

    2005-01-01

    Interspecies nuclear transfer (NT) could be an alternative to replicate animals when supply of recipient oocytes is limited or in vitro embryo production systems are incomplete. In the present study, embryonic development was assessed following interspecies NT of donor cumulus cells derived from yak and dog into the recipient ooplasm of domestic cow. The percentages of fusion and subsequent embryo development to the eight-cell stage of interspecies NT embryos were comparable to those of intraspecies NT embryos (cow-cow NT embryos). The percentage of development to blastocysts was significantly lower (p dog-cow NT embryos, only one embryo (0.4%) developed to the blastocyst stage. These results indicate that interspecies NT embryos possess equally developmental competence to the eight-cell stage as intraspecies NT embryos, but the development to blastocysts is very low when dog somatic cells are used as the donor nuclei.

  20. Beam dynamics analysis of femtosecond microbunches produced by the staged electron laser acceleration experiment

    Directory of Open Access Journals (Sweden)

    F. Zhou

    2003-05-01

    Full Text Available Preservation of the femtosecond (fs microbunches, created during laser acceleration, is a crucial step to enable staging of the laser acceleration process. This paper focuses on the optimization of the beam dynamics of fs microbunches transported through the staged electron laser acceleration (STELLA-II experiment being carried out at the Brookhaven National Laboratory Accelerator Test Facility. STELLA-II consists of an inverse free electron laser (IFEL untapered undulator, which acts as an electron beam energy modulator; a magnetic chicane, which acts as a buncher; a second IFEL tapered undulator, which acts as an accelerator; and a dipole, which serves as an energy spectrometer. When the energy-modulated macrobunch traverses through the chicane and a short drift space, microbunches of order fs in duration (i.e., ∼3  fs FWHM are formed. The 3-fs microbunches are accelerated by interacting with a high-power CO_{2} laser beam in the following tapered undulator. These extremely short microbunches may experience significant space charge and coherent synchrotron radiation effects when traversing the STELLA-II transport line. These effects are analyzed and the safe operating conditions are determined. With less than 0.5-pC microbunch charge, both microbunch debunching and emittance growth are negligible, and the energy-spread increase is less than 5%. These results are also useful for the laser electron acceleration project at SLAC and in possible future programs where the fs microbunches are employed for other purposes.

  1. Effect of pressure relaxation during the laser heating and electron-ion relaxation stages

    Energy Technology Data Exchange (ETDEWEB)

    Chimier, B.; Tikhonchuk, V.T.; Hallo, L. [Univ Bordeaux 1, CEA, CNRS, CELIA, UMR 5107, 33 - Talence (France)

    2008-09-15

    The multi-phase equation of state by Bushman et al. (Sov. Tech. Rev. 5:1-44, 2008) is modified to describe states with different electron and ion temperatures and it is applied to the non-equilibrium evolution of an aluminum sample heated by a subpicosecond laser pulse. The sample evolution is described by the two-temperature model for the electron and ion temperatures, while the pressure and density are described by a simplified relaxation equation. The pressure relaxation in the heating stage reduces the binding energy and facilitates the electron-driven ablation. The model is applied to estimate the ablation depth of an Al target irradiated by a subpicosecond laser pulse. It improves the agreement with the experimental data and provides a new explanation of the ablation process. (authors)

  2. NASAwide electronic publishing system-prototype STI electronic document distribution: Stage-4 evaluation report. Part 2; Appendices

    Science.gov (United States)

    Tuey, Richard C.; Collins, Mary; Caswell, Pamela; Haynes, Bob; Nelson, Michael L.; Holm, Jeanne; Buquo, Lynn; Tingle, Annette; Cooper, Bill; Stiltner, Roy

    1996-01-01

    This evaluation report contains an introduction, seven chapters, and five appendices. The Introduction describes the purpose, conceptual framework, functional description, and technical report server of the Scientific and Technical Information (STI) Electronic Document Distribution (EDD) project. Chapter 1 documents the results of the prototype STI EDD in actual operation. Chapter 2 documents each NASA center's post processing publication processes. Chapter 3 documents each center's STI software, hardware. and communications configurations. Chapter 7 documents STI EDD policy, practices, and procedures. The appendices consist of (A) the STI EDD Project Plan, (B) Team members, (C) Phasing Schedules, (D) Accessing On-line Reports, and (E) Creating an HTML File and Setting Up an xTRS. In summary, Stage 4 of the NASAwide Electronic Publishing System is the final phase of its implementation through the prototyping and gradual integration of each NASA center's electronic printing systems, desk top publishing systems, and technical report servers, to be able to provide to NASA's engineers, researchers, scientists, and external users, the widest practicable and appropriate dissemination of information concerning its activities and the result thereof to their work stations.

  3. Estádios de desenvolvimento embrionário e localização do embrião zigótico em sementes de citros Embryo development stage and the location of embryo zygotic in the seed of citrine

    Directory of Open Access Journals (Sweden)

    Valtemir Gonçalves Ribeiro

    1999-08-01

    Full Text Available Objetivou-se estudar o comportamento de embriões zigóticos e nucelares aos 120, 130, 140 e 150 dias após serem efetuadas hibridações controladas entre a laranjeira 'Natal' (Citrus sinensis Osb. e o parental masculino Poncirus trifoliata (L. Raf. Em cada data, as sementes foram removidas, e os embriões excisados foram caracterizados em estádios de desenvolvimento (globular, cordiforme, torpedo e cotiledonar; coloração (clorofilado ou não; e localização na semente (próximo à micrópila ou mais interiormente. A partir dessas características, foram construídas tabelas de contingência para testar hipóteses de independência entre elas, mediante o teste exato de Fisher e chi² (qui-quadrado. Relações de dependência foram verificadas entre as características: estádios de desenvolvimento embrionário com a localização na semente; estádios de desenvolvimento embrionário com a natureza da plântula (zigótica ou nucelar; e entre natureza da plântula com a localização do embrião na semente. Verificou-se que os embriões zigóticos excisados de frutos com 130 a 150 dias da hibridação controlada, localizam-se, em grande maioria, próximos à região micropilar da semente, em estádio globular e cordiforme de desenvolvimento.Controlled hybridizations between 'Natal' orange variety (Citrus sinensis Osb. and male parent Poncirus trifoliata (L. Raf. were performed in order to study zygotic and nucellar embryos behaviour at 120, 130, 140 and 150 days. At very date the seeds were removed and the embryos excised to characterize: development stage (globular, cordiform, torpedo and cotyledonal; colour (with or without chlorophyll; and location in the seed (close to the micropyle or more internal in the seed. From these characteristics contingency tables were evaluated to test independency hypothesis through Fisher test and chi² (chi-square. Dependence relationships were observed between the following characteristics: stages of the

  4. Transmission electron microscopic observation of body cuticle structures of phoretic and parasitic stages of Parasitaphelenchinae nematodes.

    Directory of Open Access Journals (Sweden)

    Taisuke Ekino

    Full Text Available Using transmission electron microscopy, we examined the body cuticle ultrastructures of phoretic and parasitic stages of the parasitaphelenchid nematodes Bursaphelenchus xylophilus, B. conicaudatus, B. luxuriosae, B. rainulfi; an unidentified Bursaphelenchus species, and an unidentified Parasitaphelenchus species. Nematode body cuticles usually consist of three zones, a cortical zone, a median zone, and a basal zone. The phoretic stages of Bursaphelenchus spp., isolated from the tracheal systems of longhorn beetles or the elytra of bark beetles, have a thick and radially striated basal zone. In contrast, the parasitic stage of Parasitaphelenchus sp., isolated from bark beetle hemocoel, has no radial striations in the basal zone. This difference probably reflects the peculiar ecological characteristics of the phoretic stage. A well-developed basal radially striated zone, composed of very closely linked proteins, is the zone closest to the body wall muscle. Therefore, the striation is necessary for the phoretic species to be able to seek, enter, and depart from host/carrier insects, but is not essential for internal parasites in parasitaphelenchid nematodes. Phylogenetic relationships inferred from near-full-length small subunit ribosomal RNA sequences suggest that the cuticle structures of parasitic species have apomorphic characters, e.g., lack of striation in the basal zone, concurrent with the evolution of insect parasitism from a phoretic life history.

  5. Positron annihilation and electron microscopy study in the early stage of fatigue of polycrystalline copper

    International Nuclear Information System (INIS)

    Diaz, L.; Pareja, R.; Pedrosa, M.A.; Gonzalez, R.

    1985-01-01

    Positron annihilation and transmission electron microscopy are used to study the early stage of fatigue in polycrystalline copper cyclically deformed at various temperatures. The concentration of positron traps is correlated to the cumulative plastic strain and to the work done during deformation. The average lifetimes of the trapped positrons are (177 +- 4) and (186 +- 3) ps for samples fatigued at T 15 s -1 for the samples deformed at T <= 293 K. Vacancy clusters like small dislocation loops, are proposed as the main defects responsible for the positron trapping. (author)

  6. Review of input stages used in front end electronics for particle detectors

    CERN Document Server

    Kaplon, J

    2015-01-01

    In this paper we present noise analysis of the input stages most commonly used in front end electronics for particle detectors. Analysis shows the calculation of the input referenced noise related to the active devices. It identifies the type, parallel or series, of the equivalent noise sources related to the input transistors, which is the important input for the further choice of the signal processing method. Moreover we calculate the input impedance of amplifiers employed in applications where the particle detector is connected to readout electronics by means of transmission line. We present schematics, small signal models,a complete set of equations, and results of the major steps of calculations for all discussed circuits.

  7. Future aspects of micromanipualtion with embryos for

    African Journals Online (AJOL)

    Embryo micromanipulation techniques and their potential genetic impact in dairy cattle are discussed. In addition, some aspects of gene transfer are mentioned. Only the technique of splitting bovine embryos and the subsequent transfer of halfembryos has reached a stage which might make its application to cattle breeding ...

  8. Desempenho de diferentes estádios embrionários no cultivo in vitro de embriões de 'Pêra Rio' x 'Poncã' Perfomance of different embryo stage of sweet orange x mandarin cultivated in vitro

    Directory of Open Access Journals (Sweden)

    Edvan Alves Chagas

    2003-12-01

    Full Text Available Objetivou-se verificar qual o melhor estádio embrionário para o cultivo de embriões imaturos oriundos de frutos provenientes de hibridação entre 'Pêra Rio' x 'Poncã' , bem como o efeito de diferentes concentrações do meio de cultura MT. Os embriões em diferentes estádios de desenvolvimento (globulares, torpedo e cordiforme foram excisados e inoculados em tubos de ensaio contendo 15 mL do meio MT com diferentes concentrações (0; 50; 100 e 150% da composição original e acrescido de 50 g.L-1 de sacarose. Após a inoculação, os embriões foram incubados à 27±1ºC, fotoperíodo de 16 horas e irradiância de 32 mmol.m-2.s-1. Após 90 dias, avaliou-se o comprimento da parte aérea e do sistema radicular, massa fresca e número de folhas das plântulas. Melhor desenvolvimento dos embriões imaturos foi obtido em estádio cotiledonar e com a concentração de 150% do meio MT.Embryos obtained from Citrus sinensis Osbeck 'Pêra Rio' x Citrus reticulata Blanco 'Poncã' crossings were excised in diverse phases of development and cultivated in different medium concentrations. Embryos in globular, torped and cotiledonary stage were excised and inoculated individually in test tubes with 15 mL in distinct MT medium concentrations (0; 50; 100 and 150% of original composition and added sucrose (50 g.L-1. After inoculation, the embryos were maintained in growth room at 27±1ºC, 16 hour photoperiod and 32 umol.m-2.s-1 irradiance. After 90 days, the length of the aerial part and roots system, fresh mass and number of leaves, were evaluated. The best results were obtained by incubating embryos in the cotiledonary stage, in MT medium with concentrations of 150%.

  9. Toward embedded laboratory automation for smart Lab-on-a-Chip embryo arrays.

    Science.gov (United States)

    Wang, Kevin I-Kai; Salcic, Zoran; Yeh, Johnny; Akagi, Jin; Zhu, Feng; Hall, Chris J; Crosier, Kathryn E; Crosier, Philip S; Wlodkowic, Donald

    2013-10-15

    Lab-on-a-Chip (LOC) biomicrofluidic technologies are rapidly emerging bioanalytical tools that can miniaturize and revolutionize in situ research on embryos of small vertebrate model organisms such as zebrafish (Danio rerio) and clawed African frog (Xenopus laevis). Despite considerable progress being made in fabrication techniques of chip-based devices, they usually still require excessive and manual actuation and data acquisition that significantly reduce throughput and introduce operator-related analytical bias. This work describes the development of a proof-of-concept embedded platform that integrates an innovative LOC zebrafish embryo array technology with an electronic interface to provide higher levels of laboratory automation for in situ biotests. The integrated platform was designed to perform automatic immobilization, culture and treatment of developing zebrafish embryos during fish embryo toxicity (FET) biotests. The system was equipped with a stepper motor driven stage, solenoid-actuated pinch valves, miniaturized peristaltic pumps as well as Peltier heating module. Furthermore, a Field Programmable Gate Array (FPGA) was used to implement an embedded hardware/software solution and interface to enable real-time control over embryo loading and immobilization; accurate microfluidic flow control; temperature stabilization and also automatic time-resolved image acquisition of developing zebrafish embryos. This work presents evidence that integration of embedded electronic interfaces with microfluidic chip-based technologies can bring the Lab-on-a-Chip a step closer to fully automated analytical systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. The destruction of parasitic resistant stages in sewage sludge by irradiation with low accelerating voltage electrons

    International Nuclear Information System (INIS)

    Enigk, K.; Holl, P.; Dey-Hazra, A.; Polymer-Physik G.m.b.H. und Co. K.G., Tuebingen

    1975-01-01

    The destroying effect of ionizing radiation on parasitic resistant stages in sludge has been tested. Suitable for that process is an electron beam accelerator which will be provided with energy from the electric power supply network which can be switched on and off according to the requirements. Such modern utilities have an enormous beam capacity and a high operating safety. The process is working according to the continuous flow principle and at room temperature. In a series of 13 experiments the effect of different doses has been tested. A dose of 480 kRad (accelerating voltage: 400 kV, beam current: 10 mA , irradiation time: 24 sec.) can easily obtained in practical work and is economically acceptable. By these means approximately 97% of the following parasitic stages have been destroyed: undeveloped eggs of Ascaris suum, Trichuris suis, Fasciola hepatica and gastrointestinal strongylids of pigs, embryonated eggs of Capillaria obsignata and probably of Taenia spec. A few third-stage larvae of Oesophagostomum (Strongylidae) of pigs survived even 108 sec of irradiation; however, they did not develop to maturity in the definitive host. Approximately 25% of the sporulated oocysts of Eimeria tenella were still infective after 108 sec of irradiation. (orig.) [de

  11. Evaluation of high step-up power electronics stages in thermoelectric generator systems

    DEFF Research Database (Denmark)

    Sun, Kai; Ni, Longxian; Chen, Min

    2013-01-01

    To develop practical thermoelectric generator (TEG) systems, especially radioisotope thermoelectric power supplies for deep-space exploration, a power conditioning stage with high step-up gain is indispensable. This stage is used to step up the low output voltage of thermoelectric generators to t...... efficiency and input current ripples. The interleaved boost converter with an auxiliary transformer is found to be the most suitable topology for TEG applications, which is verified by experiments....... to the required high level. Furthermore, maximum power point tracking control for TEG modules needs to be implemented into the power electronics stages. In this paper, the temperature-dependent electrical characteristics of a thermoelectric generator are analyzed in depth. Three typical high step-up power...... converters suitable for TEG applications are discussed: an interleaved boost converter, a boost converter with a coupled inductor and an interleaved boost converter with an auxiliary transformer. A general comparison of the three high step-up converters is conducted to study the step-up gain, conversion...

  12. Comparative anatomy and morphology of Vitis vinifera (Vitaceae) somatic embryos from solid- and liquid-culture-derived proembryogenic masses.

    Science.gov (United States)

    Jayasankar, S; Bondada, Bhaskar R; Li, Zhijian; Gray, D J

    2003-07-01

    Ontogeny of somatic embryos of grapevine (Vitis vinifera) produced from solid- and liquid-culture-derived proembryogenic masses (PEM) was compared using light and scanning electron microscopy. Somatic embryos produced from solid-medium-derived PEM (SPEM) had large cotyledons, little or no visible suspensor structure, and a relatively undeveloped concave shoot apical meristem, whereas those from liquid-medium-derived PEM (LPEM) had smaller cotyledons, a distinct suspensor, and a flat-to-convex shoot apical meristem. The convex shoot apical meristem in LPEM-derived somatic embryos formed as early as the heart stage of development; it was 4-6 cell layers deep and rich in protein. Suspensors persisted in fully developed and mature LPEM-derived somatic embryos. The SPEM-derived somatic embryos exhibited dormancy, as do mature zygotic embryos, which also have a rudimentary suspensor, whereas LPEM-derived embryos were not dormant. We hypothesize that the presence of a persistent suspensor in LPEM-derived somatic embryos modulates development, ultimately resulting in rapid germination and a high plant-regeneration rate.

  13. Nonlinear resonances in a multi-stage free-electron laser amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, S. [Graduate Univ. for Advanced Studies, Ibaraki-ken (Japan); Takayama, K. [National Lab. for High Energy Physics, Ibaraki-ken (Japan)

    1995-12-31

    A two-beam accelerator (TBA) is a possible candidate of future linear colliders, in which the demanded rf power is provided by a multi-stage free-electron laser (MFEL). After if amplification in each stage, a driving beam is re-accelerated by an induction unit and propagates into the next stage. Recently it has been recognized that the multi-stage character of the MFEL causes resonances between its periodicity and the synchrotron motion in an rf bucket. Since the synchrotron oscillation is strongly modulated by the resonance and at the worst a large fraction of particles is trapped in the resonance islands, the nonlinear resonances in the FEL longitudinal beam dynamics can lead to notable degradation of the MFEL performance, such as output fluctuation and phase modulation which have been big concerns in the accelerator society. The overall efficiency of the MFEL and the quality of the amplified microwave power are key issues for realizing the TBA/FEL Particularly the rf phase and amplitude errors must be maintained within tolerance. One of significant obstacles is an amplification of undesired modes. If a small-size waveguide is employed, the FEL resonance energies for undesired higher order modes shift very far from that for a fundamental mode; so it is possible to prevent higher order modes from evolving. Such a small-size waveguide, however, gives a high power density in the FEL. Simulation results have demonstrated that the nonlinear resonances occur in die FEL longitudinal motion when the power density exceeds some threshold. An analytical method for studying the nonlinear resonance in the TBA/FEL is developed based on the macroparticle model which can describe analytically the drastic behaviors in the evolutions of the phase and amplitude. In the theory the basic 1D-FEL equations are reduced to a nonlinear pendulum equation with respect to the ponderomotive phase.

  14. Hospital Characteristics are Associated With Readiness to Attain Stage 2 Meaningful Use of Electronic Health Records.

    Science.gov (United States)

    Kim, Jungyeon; Ohsfeldt, Robert L; Gamm, Larry D; Radcliff, Tiffany A; Jiang, Luohua

    2017-06-01

    To examine the difference between rural and urban hospitals as to their overall level of readiness for stage 2 meaningful use of electronic health records (EHRs) and to identify other key factors that affect their readiness for stage 2 meaningful use. A conceptual framework based on the theory of organizational readiness for change was used in a cross-sectional multivariate analysis using 2,083 samples drawn from the HIMSS Analytics survey conducted with US hospitals in 2013. Rural hospitals were less likely to be ready for stage 2 meaningful use compared to urban hospitals in the United States (OR = 0.49) in our final model. Hospitals' past experience with an information exchange initiative, staff size in the information system department, and the Chief Information Officer (CIO)'s responsibility for health information management were identified as the most critical organizational contextual factors that were associated with hospitals' readiness for stage 2. Rural hospitals lag behind urban hospitals in EHR adoption, which will hinder the interoperability of EHRs among providers across the nation. The identification of critical factors that relate to the adoption of EHR systems provides insights into possible organizational change efforts that can help hospitals to succeed in attaining meaningful use requirements. Rural hospitals have increasingly limited resources, which have resulted in a struggle for these facilities to attain meaningful use. Given increasing closures among rural hospitals, it is all the more important that EHR development focus on advancing rural hospital quality of care and linkages with patients and other organizations supporting the care of their patients. © 2016 National Rural Health Association.

  15. Mouse embryos cultured in amniotic fluid | Oettle | South African ...

    African Journals Online (AJOL)

    The embryos were cultured for 72 hours at 37°C in 5% carbon dioxide in air. Osmolarity, pH, partial arterial carbon dioxide pressure and HCO; were checked before culture and again at the end of culture. Embryos were assessed according to the stage of development, namely degenerate embryos, morulae and blastocysts.

  16. Xenopus laevis embryos and tadpoles as models for testing for ...

    African Journals Online (AJOL)

    The toxicity of bio available Zn, Cu, Pb, and Cd on the life stages of Xenopus laevis embryos and tadpoles was investigated. Cu and Cd were found to affect the hatching success of the embryos, with a strong negative relationship existing between the increase in Cu concentrations and the hatching of the embryos.

  17. Superovulation and embryo recovery in Boer goats treated with ...

    African Journals Online (AJOL)

    Lehloenya

    These pregnancy rates obtained were also indicative of an acceptable procedure of embryo transfer used in this trial. The differences obtained could also be attributed to the stage of development of the embryos, as in this trial blastocysts were used. In most trials transferable embryos (morulae and blastocysts) were used.

  18. Release of somatic embryogenic potential from excised zygotic embryos of carrot and maintenance of proembryonic cultures in hormone-free medium

    Science.gov (United States)

    Smith, D. L.; Krikorian, A. D.

    1989-01-01

    Excised zygotic embryos, mericarps ("seeds") and hypocotyls of seedlings of cultivated carrot Daucus carota cv. Scarlet Nantes were evaluated for their ability to generate somatic embryos on a semisolid hormone-free nutrient medium. Neither intact zygotic embryos nor hypocotyls ever produced somatic embryos. However, mericarps and broken zygotic embryos were excellent sources for somatic embryo production (response levels as high as 86%). Somatic embryo formation was highest from cotyledons, but was also observed on isolated hypocotyls and root tips of mature zygotic embryos. On media containing unreduced nitrogen, somatic embryo formation led to the generation of vigorous cultures comprised entirely of somatic embryos at various stages of development which in turn proliferated still other somatic embryos. However, a medium was devised which when 1-5 mM NH4+ was the sole nitrogen source, led only to a proliferation of globular proembryos. Sustained subculturing of these proembryos at 2-3 week intervals enabled establishment of highly uniform cultures in which no further development into more mature stages of embryonic development occurred. These have been maintained, without decline, as morphogenetically competent proembryonic globules for over ten months. A basal medium containing from 1-5 mM NH4+ as the sole nitrogen source appears not to be inductive to somatic proembryo formation. Instead, such a medium is best thought of as permissive to the expression of embryogenically determined cells within zygotic embryos. By excising and breaking or wounding zygotic embryos, constituent cells are probably released from positional or chemical restraints and thus are able to express their innate embryogenic potential. Once a proembryonic culture is established, this medium containing 1-5 mM NH4+ as the sole nitrogen source provides a nonpermissive environment to the development and growth of later embryonic stages, but it does allow the continued formation and

  19. Superovulation Response and In vivo Embryo Production Potential ...

    African Journals Online (AJOL)

    to a search dish containing holding medium and grouped in to embryos and UFO under a stereomicroscope (MotisSMZ 140/143®, Roanoke, USA). The embryos were graded for their developmental stage (from stage 1 = 1-cell to stage 9 = expanded hatched blastocyst) and quality (from quality 1 = excellent to quality 4.

  20. Developmental competence of porcine chimeric embryos produced by aggregation

    DEFF Research Database (Denmark)

    Li, Juan; Jakobsen, Jannik E.; Xiong, Qiang

    2015-01-01

    either by parthenogenetic activation (PA) or handmade cloning (HMC). Results showed that the developmental competence of chimeric embryos, evaluated based on their blastocyst rate and total cell number per blastocyst, was increased when two whole 2-cell stage embryos (PA or HMC) were aggregated....... In comparison, when two blastomeres were aggregated, the developmental competence of the chimeric embryos decreased if the blastomeres were either from PA or from HMC embryos, but not if they were from different sources, i.e. one PA and one HMC blastomere. To evaluate the cell contribution in embryo formation......, aggregation was made with HMC embryos cloned using EGFP transgenic cells; the cell contribution in the formation of the inner cell mass or trophectoderm was random in chimeric blastocysts. Finally, two blastomeres from 2-cell stage embryos were fused to construct tetraploid embryos, and when diploid...

  1. Radioprotective effects of dimethyl sulfoxide in golden hamster embryo cells exposed to gamma rays at 77 K. I. Radical formation as studied by electron spin resonance

    International Nuclear Information System (INIS)

    Miyazaki, T.; Hayakawa, Y.; Suzuki, K.; Suzuki, M.; Watanabe, M.

    1990-01-01

    Formation of free radicals in golden hamster embryo (GHE) cells in the frozen living state by gamma irradiation has been studied by electron spin resonance spectroscopy at 4.2 and 77 K. The relative yields of H atoms, OH radicals, and organic radicals trapped in the irradiated GHE cells are 12, 72, and 16%, respectively, of total radical yields. When dimethylsulfoxide (DMSO) is added to GHE cells at 77 K, a large quantity of CH2SOCH3 radicals (DMSO radicals) are formed after gamma irradiation. The yields of OH radicals are not affected by the addition of DMSO. When the GHE cell-DMSO mixtures are irradiated with gamma rays at 77 K and then warmed to 111 K, the OH radicals decay, whereas the DMSO radicals do not increase complementarily. Moreover, the decay rates of the OH radicals at 111 K do not depend upon the concentration of DMSO. Thus OH radicals do not react with DMSO during warming of the irradiated sample. When H atoms are produced by gamma irradiation of acid ice at 60 K, the decay rates of the H atoms at 77 K increase with increasing DMSO concentration, indicating that DMSO reacts with H atoms (CH3SOCH3 + H----.CH2SOCH3 + H2) at 77 K by quantum-mechanical tunneling. When the GHE cell-DMSO mixture is irradiated with gamma rays at 77 or 4.2 K in the dark, DMSO ions are produced in addition to DMSO radicals. Therefore it is concluded that DMSO does not scavenge OH radicals, but does capture H atoms, holes and/or electrons in the gamma-irradiated cells, resulting in the remarkable formation of DMSO radicals. This scavenger effect of DMSO may be related to the radioprotection of DMSO against cell killing

  2. White communicating rami in human embryos at the end of the fifth week.

    Science.gov (United States)

    Bruska, M; Łupicka, J; Pytel, A; Woźniak, W

    2010-05-01

    White communicating rami were traced in 8 human embryos of developmental stages 14 and 15 (aged 33 and 36 postovulatory days, respectively). In embryos at stage 14 the white communicating rami were found in the spinal nerves T1 to T9. In embryos at stage 15 the white communicating rami were present at the spinal cord levels T1 to L3.

  3. Effects of Fluoxetine on Human Embryo Development.

    Science.gov (United States)

    Kaihola, Helena; Yaldir, Fatma G; Hreinsson, Julius; Hörnaeus, Katarina; Bergquist, Jonas; Olivier, Jocelien D A; Åkerud, Helena; Sundström-Poromaa, Inger

    2016-01-01

    The use of antidepressant treatment during pregnancy is increasing, and selective serotonin reuptake inhibitors (SSRIs) are the most widely prescribed antidepressants in pregnant women. Serotonin plays a role in embryogenesis, and serotonin transporters are expressed in two-cell mouse embryos. Thus, the aim of the present study was to evaluate whether fluoxetine, one of the most prescribed SSRI antidepressant world-wide, exposure influences the timing of different embryo developmental stages, and furthermore, to analyze what protein, and protein networks, are affected by fluoxetine in the early embryo development. Human embryos (n = 48) were randomly assigned to treatment with 0.25 or 0.5 μM fluoxetine in culture medium. Embryo development was evaluated by time-lapse monitoring. The fluoxetine-induced human embryo proteome was analyzed by shotgun mass spectrometry. Protein secretion from fluoxetine-exposed human embryos was analyzed by use of high-multiplex immunoassay. The lower dose of fluoxetine had no influence on embryo development. A trend toward reduced time between thawing and start of cavitation was noted in embryos treated with 0.5 μM fluoxetine (p = 0.065). Protein analysis by shotgun mass spectrometry detected 45 proteins that were uniquely expressed in fluoxetine-treated embryos. These proteins are involved in cell growth, survival, proliferation, and inflammatory response. Culturing with 0.5 μM, but not 0.25 μM fluoxetine, caused a significant increase in urokinase-type plasminogen activator (uPA) in the culture medium. In conclusion, fluoxetine has marginal effects on the timing of developmental stages in embryos, but induces expression and secretion of several proteins in a manner that depends on dose. For these reasons, and in line with current guidelines, the lowest possible dose of SSRI should be used in pregnant women who need to continue treatment.

  4. Brachylaima cribbi (Digenea: Brachylaimidae): scanning electron microscopical observations of the life-cycle stages.

    Science.gov (United States)

    Butcher, A R; Brealey, J K; Grove, D I; Dymock, R B

    2002-09-01

    Brachylaima cribbi is a recently described species of terrestrial trematode that infects mammals and birds with helicid land snails as its first and second intermediate hosts. The adult worm is 2.5-6.0 mm long by 0.5-0.8 mm wide being a long slender cylindrical worm with oral and ventral suckers in the anterior quarter and genital pore in the posterior quarter. Scanning electron microscopy shows that there is a dense covering of tegumental spines at the anterior end which diminishes towards the posterior extremities of the worm. Development of spines was observed in juvenile and mature adult worms. In young worms 1-3 weeks post infection (wpi) spines appear as buds with a serrated edge each having 1-4 spikes per spine. As the worm ages the spines broaden and by 5 wpi the number of spikes per spine increases to an average of 8.1. The serial development of oral sucker papillae in the cercaria, metacercaria and adult worm was observed with the finding of an elongated papilla with a bifurcated tip on the cercaria becoming a shorter and thicker elongated papilla with a large central stoma on the metacercaria. In the adult worm, this papilla becomes dome-shaped with a small central stoma. For some of these papillae a cilium could be seen extended from the central stoma. Other life-cycle stages illustrated were the hatched egg with an extruded egg membrane minus an operculum and a portion of the branched sporocyst dissected from the digestive gland of the land snail Theba pisana showing a terminal birth pore. Scanning electron microscopy morphological features of the adult worm observed for the first time in a Brachylaima were the unarmed cirrus extended from the genital pore with released sperm present and the Laurer's canal opening visible in tegumental folds on the dorsal surface approximately 300 microm posterior to the genital pore.

  5. Retinoic acid signalling in the zebrafish embryo is necessary during pre-segmentation stages to pattern the anterior-posterior axis of the CNS and to induce a pectoral fin bud.

    Science.gov (United States)

    Grandel, Heiner; Lun, Klaus; Rauch, Gerd-Jörg; Rhinn, Muriel; Piotrowski, Tatjana; Houart, Corinne; Sordino, Paolo; Küchler, Axel M; Schulte-Merker, Stefan; Geisler, Robert; Holder, Nigel; Wilson, Stephen W; Brand, Michael

    2002-06-01

    A number of studies have suggested that retinoic acid (RA) is an important signal for patterning the hindbrain, the branchial arches and the limb bud. Retinoic acid is thought to act on the posterior hindbrain and the limb buds at somitogenesis stages in chick and mouse embryos. Here we report a much earlier requirement for RA signalling during pre-segmentation stages for proper development of these structures in zebrafish. We present evidence that a RA signal is necessary during pre-segmentation stages for proper expression of the spinal cord markers hoxb5a and hoxb6b, suggesting an influence of RA on anteroposterior patterning of the neural plate posterior to the hindbrain. We report the identification and expression pattern of the zebrafish retinaldehyde dehydrogenase2 (raldh2/aldh1a2) gene. Raldh2 synthesises retinoic acid (RA) from its immediate precursor retinal. It is expressed in a highly ordered spatial and temporal fashion during gastrulation in the involuting mesoderm and during later embryogenesis in paraxial mesoderm, branchial arches, eyes and fin buds, suggesting the involvement of RA at different times of development in different functional contexts. Mapping of the raldh2 gene reveals close linkage to no-fin (nof), a newly discovered mutant lacking pectoral fins and cartilaginous gill arches. Cloning and functional tests of the wild-type and nof alleles of raldh2 reveal that nof is a raldh2 mutant. By treating nof mutants with RA during different time windows and by making use of a retinoic acid receptor antagonist, we show that RA signalling during pre-segmentation stages is necessary for anteroposterior patterning in the CNS and for fin induction to occur.

  6. Frontal Cortex Transcriptome Analysis of Mice Exposed to Electronic Cigarettes During Early Life Stages

    Science.gov (United States)

    Lauterstein, Dana E.; Tijerina, Pamella B.; Corbett, Kevin; Akgol Oksuz, Betul; Shen, Steven S.; Gordon, Terry; Klein, Catherine B.; Zelikoff, Judith T.

    2016-01-01

    Electronic cigarettes (e-cigarettes), battery-powered devices containing nicotine, glycerin, propylene glycol, flavorings, and other substances, are increasing in popularity. They pose a potential threat to the developing brain, as nicotine is a known neurotoxicant. We hypothesized that exposure to e-cigarettes during early life stages induce changes in central nervous system (CNS) transcriptome associated with adverse neurobiological outcomes and long-term disease states. To test the hypothesis, pregnant C57BL/6 mice were exposed daily (via whole body inhalation) throughout gestation (3 h/day; 5 days/week) to aerosols produced from e-cigarettes either with nicotine (13–16 mg/mL) or without nicotine; following birth, pups and dams were exposed together to e-cigarette aerosols throughout lactation beginning at postnatal day (PND) 4–6 and using the same exposure conditions employed during gestational exposure. Following exposure, frontal cortex recovered from ~one-month-old male and female offspring were excised and analyzed for gene expression by RNA Sequencing (RNA-Seq). Comparisons between the treatment groups revealed that e-cigarette constituents other than nicotine might be partly responsible for the observed biological effects. Transcriptome alterations in both offspring sexes and treatment groups were all significantly associated with downstream adverse neurobiological outcomes. Results from this study demonstrate that e-cigarette exposure during early life alters CNS development potentially leading to chronic neuropathology. PMID:27077873

  7. Transmission electron microscopy reveals distinct macrophage- and tick cell-specific morphological stages of Ehrlichia chaffeensis.

    Directory of Open Access Journals (Sweden)

    Sarah E Dedonder

    Full Text Available BACKGROUND: Ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis. Despite the induction of an active host immune response, the pathogen has evolved to persist in its vertebrate and tick hosts. Understanding how the organism progresses in tick and vertebrate host cells is critical in identifying effective strategies to block the pathogen transmission. Our recent molecular and proteomic studies revealed differences in numerous expressed proteins of the organism during its growth in different host environments. METHODOLOGY/PRINCIPAL FINDINGS: Transmission electron microscopy analysis was performed to assess morphological changes in the bacterium within macrophages and tick cells. The stages of pathogen progression observed included the attachment of the organism to the host cells, its engulfment and replication within a morulae by binary fission and release of the organisms from infected host cells by complete host cell lysis or by exocytosis. E. chaffeensis grown in tick cells was highly pleomorphic and appears to replicate by both binary fission and filamentous type cell divisions. The presence of Ehrlichia-like inclusions was also observed within the nucleus of both macrophages and tick cells. This observation was confirmed by confocal microscopy and immunoblot analysis. CONCLUSIONS/SIGNIFICANCE: Morphological differences in the pathogen's progression, replication, and processing within macrophages and tick cells provide further evidence that E. chaffeensis employs unique host-cell specific strategies in support of adaptation to vertebrate and tick cell environments.

  8. Rape embryogenesis. III. Embryo development in time

    Directory of Open Access Journals (Sweden)

    Teresa Tykarska

    2014-01-01

    Full Text Available It was found that the growth curve of the rape embryo axis is of triple sigmoid type. Embryo growth occurs in 3 phases corresponding to 3 different periods of development. Phase I includes growth of the apical cell up to it's division into two layers of octants. Phase II comprises the increase of the spherical proembryo to the change of its symmetry from radial to bilateral. Phase III includes, growth of the embryo from the heart stage up to the end of embryogenesis. In each phase the relative growth rate increases drastically and then diminishes. The differences in growth intensity during the same phase are several-fold. The growth intensity maximum of the embryo axis occurs in phase II. The phasic growth intensity maxima occur: in phase I during apical cell elongation, :before its division, and in phases II and III in the periods of cell division ;growth in globular and torpedo-shaped -shaped embryos.

  9. Light and transmission electron microscopic studies on trophozoites and cyst-like stages of Histomonas meleagridis from cultures.

    Science.gov (United States)

    Munsch, Mareike; Lotfi, Abdulrahman; Hafez, Hafez Mohammed; Al-Quraishy, Saleh; Mehlhorn, H

    2009-02-01

    The present study deals with Berlin strains of Histomonas meleagridis, the specimens of which were cultivated in Dwyer's medium. The light and electron microscopic examination revealed that the cultivated trophozoite stages (reaching about 10 mum in size) appeared more or less spherical, although their surface (covered by a single membrane) showed amoeba-like waves. All stages were uni-nucleated and reproduced by binary fission with an extranuclear spindle apparatus. Some trophozoites appeared ovoid and possessed a single flagellum with a typical microtubular 9 x 2 + 2 arrangement. Furthermore, the latter were characterized by an inner row of typical microtubules (remnant of an axostyle) and a Golgi apparatus (both adjacent to the nucleus), multivesicular structures, hydrogenosomes, and many food vacuoles containing either starch grains or bacteria. Their cytoplasm was densely filled with glycogen granules and ribosomes. Similar stages were also documented in the caeca and cloaca of chicken when being inoculated (via cloaca) with such culture stages. In addition to these typical trophozoites, the cultures contained a low number of 10-mum-sized spherical cyst-like stages with a surrounding amorphous layer. The cytoplasm of some of these cyst-like stages-when studied by electron microscopy-appeared with two membranes or had formed an amorphic, cyst-wall-like layer at their surface, apparently corresponding to their light microscopical appearance. Such stages might be involved in transmission from one host to another and probably have been missed before in microscopical examinations of infected poultry.

  10. Closure of the vertebral canal in human embryos and fetuses

    NARCIS (Netherlands)

    Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

    2017-01-01

    The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

  11. Integrated chip-based physiometer for automated fish embryo toxicity biotests in pharmaceutical screening and ecotoxicology.

    Science.gov (United States)

    Akagi, Jin; Zhu, Feng; Hall, Chris J; Crosier, Kathryn E; Crosier, Philip S; Wlodkowic, Donald

    2014-06-01

    Transgenic zebrafish (Danio rerio) models of human diseases have recently emerged as innovative experimental systems in drug discovery and molecular pathology. None of the currently available technologies, however, allow for automated immobilization and treatment of large numbers of spatially encoded transgenic embryos during real-time developmental analysis. This work describes the proof-of-concept design and validation of an integrated 3D microfluidic chip-based system fabricated directly in the poly(methyl methacrylate) transparent thermoplastic using infrared laser micromachining. At its core, the device utilizes an array of 3D micromechanical traps to actively capture and immobilize single embryos using a low-pressure suction. It also features built-in piezoelectric microdiaphragm pumps, embryo-trapping suction manifold, drug delivery manifold, and optically transparent indium tin oxide heating element to provide optimal temperature during embryo development. Furthermore, we present design of the proof-of-concept off-chip electronic interface equipped with robotic servo actuator driven stage, innovative servomotor-actuated pinch valves, and embedded miniaturized fluorescent USB microscope. Our results showed that the innovative device has 100% embryo-trapping efficiency while supporting normal embryo development for up to 72 hr in a confined microfluidic environment. We also showed data that this microfluidic system can be readily applied to kinetic analysis of a panel of investigational antiangiogenic agents in transgenic zebrafish lines. The optical transparency and embryo immobilization allow for convenient visualization of developing vasculature patterns in response to drug treatment without the need for specimen re-positioning. The integrated electronic interfaces bring the lab-on-a-chip systems a step closer to realization of complete analytical automation. © 2014 International Society for Advancement of Cytometry.

  12. Neural network classification of sweet potato embryos

    Science.gov (United States)

    Molto, Enrique; Harrell, Roy C.

    1993-05-01

    Somatic embryogenesis is a process that allows for the in vitro propagation of thousands of plants in sub-liter size vessels and has been successfully applied to many significant species. The heterogeneity of maturity and quality of embryos produced with this technique requires sorting to obtain a uniform product. An automated harvester is being developed at the University of Florida to sort embryos in vitro at different stages of maturation in a suspension culture. The system utilizes machine vision to characterize embryo morphology and a fluidic based separation device to isolate embryos associated with a pre-defined, targeted morphology. Two different backpropagation neural networks (BNN) were used to classify embryos based on information extracted from the vision system. One network utilized geometric features such as embryo area, length, and symmetry as inputs. The alternative network utilized polar coordinates of an embryo's perimeter with respect to its centroid as inputs. The performances of both techniques were compared with each other and with an embryo classification method based on linear discriminant analysis (LDA). Similar results were obtained with all three techniques. Classification efficiency was improved by reducing the dimension of the feature vector trough a forward stepwise analysis by LDA. In order to enhance the purity of the sample selected as harvestable, a reject to classify option was introduced in the model and analyzed. The best classifier performances (76% overall correct classifications, 75% harvestable objects properly classified, homogeneity improvement ratio 1.5) were obtained using 8 features in a BNN.

  13. Survival of embryo irradiated with gamma rays by embryo culture in Brassica pekinensis Rupr

    International Nuclear Information System (INIS)

    Moue, T.

    1984-01-01

    The effect of irradiation on the survival rates and embryonic development of Brassica pekinensis RUPR. (Varieties; Kashin, Kohai 65 nichi and kairyochitose) was investigated. The purpose of this study was to seek ways of increasing the survival rates of embryos such as B.oleracea obtained through embryo culture techniques after irradiation doses affecting seed fertility and germination, for the purpose of increasing mutation rates. Embryos at different developmental stages ranging from the globular to the early heart stages were irradiated with 20 KR of gamma rays at the daily rate 0L 20 KR or 10 KR (Fig.1 and Table 1). The embryos were excised from ovules 4 to 10 days after irradiation and cultured on White's medium. The shooting and rooting rates on the 34th day of culture were higher at the dose of 10 KR/day than 20 KR/day and were lower when the materials were irradiated at the young embryonic stage (Table 3). Varietal differences in the shooting and rooting rates were also observed. The irradiated embryos survived mainly in the state of callus. It was concluded that the embryo culture technique was successful when applied to irradiated embryos excised at the young embryonic stage and that the technique affected B.pekinensis less than B.oleracea

  14. Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

    Science.gov (United States)

    Gambini, Andrés; De Stéfano, Adrián; Jarazo, Javier; Buemo, Carla; Karlanian, Florencia; Salamone, Daniel Felipe

    2016-09-01

    The low efficiency of interspecies somatic cell nuclear transfer (iSCNT) makes it necessary to investigate new strategies to improve embryonic developmental competence. Embryo aggregation has been successfully applied to improve cloning efficiency in mammals, but it remains unclear whether it could also be beneficial for iSCNT. In this study, we first compared the effect of embryo aggregation over in vitro development and blastocyst quality of porcine, bovine, and feline zona-free (ZF) parthenogenetic (PA) embryos to test the effects of embryo aggregation on species that were later used as enucleated oocytes donors in our iSCNT study. We then assessed whether embryo aggregation could improve the in vitro development of ZF equine iSCNT embryos after reconstruction with porcine, bovine, and feline ooplasm. Bovine- and porcine-aggregated PA blastocysts had significantly larger diameters compared with nonaggregated embryos. On the other hand, feline- and bovine-aggregated PA embryos had higher blastocyst cell number. Embryo aggregation of equine-equine SCNT was found to be beneficial for embryo development as we have previously reported, but the aggregation of three ZF reconstructed embryos did not improve embryo developmental rates on iSCNT. In vitro embryo development of nonaggregated iSCNT was predominantly arrested around the stage when transcriptional activation of the embryonic genome is reported to start on the embryo of the donor species. Nevertheless, independent of embryo aggregation, equine blastocyst-like structures could be obtained in our study using domestic feline-enucleated oocytes. Taken together, these results reported that embryo aggregation enhance in vitro PA embryo development and embryo quality but effects vary depending on the species. Embryo aggregation also improves, as expected, the in vitro embryo development of equine-equine SCNT embryos; however, we did not observe positive effects on equine iSCNT embryo development. Among oocytes

  15. Miniaturized embryo array for automated trapping, immobilization and microperfusion of zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    Jin Akagi

    Full Text Available Zebrafish (Danio rerio has recently emerged as a powerful experimental model in drug discovery and environmental toxicology. Drug discovery screens performed on zebrafish embryos mirror with a high level of accuracy the tests usually performed on mammalian animal models, and fish embryo toxicity assay (FET is one of the most promising alternative approaches to acute ecotoxicity testing with adult fish. Notwithstanding this, automated in-situ analysis of zebrafish embryos is still deeply in its infancy. This is mostly due to the inherent limitations of conventional techniques and the fact that metazoan organisms are not easily susceptible to laboratory automation. In this work, we describe the development of an innovative miniaturized chip-based device for the in-situ analysis of zebrafish embryos. We present evidence that automatic, hydrodynamic positioning, trapping and long-term immobilization of single embryos inside the microfluidic chips can be combined with time-lapse imaging to provide real-time developmental analysis. Our platform, fabricated using biocompatible polymer molding technology, enables rapid trapping of embryos in low shear stress zones, uniform drug microperfusion and high-resolution imaging without the need of manual embryo handling at various developmental stages. The device provides a highly controllable fluidic microenvironment and post-analysis eleuthero-embryo stage recovery. Throughout the incubation, the position of individual embryos is registered. Importantly, we also for first time show that microfluidic embryo array technology can be effectively used for the analysis of anti-angiogenic compounds using transgenic zebrafish line (fli1a:EGFP. The work provides a new rationale for rapid and automated manipulation and analysis of developing zebrafish embryos at a large scale.

  16. Multiple-embryo transfer for studying very early maternal-embryo interactions in cattle.

    Science.gov (United States)

    Gómez, E; Muñoz, M

    2015-08-01

    In the present paper, we highlight the need to study very early maternal-embryo interactions and discuss how these interactions can be addressed. Bovine species normally carry one or, less frequently, two embryos to term; there are very rare cases of triplets or higher-order multiple pregnancies in which all the offspring are born alive. Multiple-embryo transfer (MET) in cattle allows for the detection of endometrial responses in scenarios where single-embryo transfer would not. Although MET is non-physiological, the present study shows that at the very early embryonic stages, a uterus carrying zona-enclosed embryos does not exhibit non-physiological reactions. On the contrary, MET should be considered the sum of multiple individual effects triggered by developing embryos. We provide arguments to support our hypothesis that describe a rationale for current work with MET, and we discuss alternative hypotheses. Using cattle as a model, we describe how technical approaches to analyzing zona-enclosed early embryo-maternal interactions (i.e., transcriptomics, proteomics, and endometrial cell culture) can help identify molecular changes that may be difficult to observe when only a single embryo is present. We conclude that MET can be used for studying very early maternal-embryo interactions in vivo in monotocous species. Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/150/2/R35/suppl/DC1. © 2015 Society for Reproduction and Fertility.

  17. Silver nanoparticles induce developmental stage-specific embryonic phenotypes in zebrafish

    Science.gov (United States)

    Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Osgood, Christopher J.; Xu, Xiao-Hong Nancy

    2013-11-01

    to the NPs than cleavage and segmentation stage embryos, and do not develop abnormally. These important findings suggest that the Ag NPs are not simple poisons, and they can target specific pathways in development, and potentially enable target specific study and therapy for early embryonic development. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03210h

  18. Cooling strategies for brazilian flounder Paralichthys orbignyanus embryos.

    Science.gov (United States)

    Varela, A S; Cardoso, T F; Fernandes E Silva, E; Goularte, K L; Okamoto, M H; Sampaio, L A; Jardim, R D; Corcini, C D

    Paralichthys orbignyanus is the species of the greatest potential for marine and estuarine fish farming in southern Brazil. Consequently, embryo cryopreservation becomes an important tool for increasing their production. To evaluate the effects of cooling protocols on the viability of embryos of P. orbignyanus at two stages of development (neurula and early differentiation of the tail). Control embryos were maintained at 23 degree C and treated embryos were cooled to 15 degree C, 10 degree C and 5 degree C at rapid, moderate and slow cooling rates. Then embryos were maintained at these different temperatures for 30, 60 and 90 min and the loss of viability assessed as hatching rates (HR) and morphologically normal larvae (MNL). The average HR for embryos following cooling was higher for those at the tail stage compared to the neurula stage (Pcooling. Also for tail stage embryos, there was no difference between MNL of control and rapidly cooled embryos. As first steps in the development of cryopreservation methods for P. orbignyanus embryos, the use of a rapid cooling and holding at 5 degree C for 30 min are recommended.

  19. Classification of embryo sacs in the Eragrostis curvula Complex

    Directory of Open Access Journals (Sweden)

    T. B. Vorster

    1984-12-01

    Full Text Available At each of 17 collecting points between Johannesburg and Brits in the Transvaal, three plants which belong to the  Eragrostis curvula Complex were collected and studied. A total o f 3 902 embryo sacs was examined in this sample. Of the embryo sacs examined, 3 306 were apomictic by means of diplospory, whereas 99 were sexual monosporic Polygonum-type embryo sacs. One hundred and nineteen embryo sacs were abnormal or divergent, and 378 were degenerated. There are indications that seasonal climatic fluctuations may be responsible for embryo sacs developing abnormally or degenerating. Simple and multiple correlations confirmed that sexual embryo sacs usually do not develop abnormally or degenerate during the later developmental stages. This finding lends credence to both the system of classification of individual embryo sacs and to the validity of the estimate of the proportion of sexuality of the plants sampled at each sampling point.

  20. Improvement of bovine in vitro embryo production by vitamin K₂ supplementation.

    Science.gov (United States)

    Baldoceda-Baldeon, Luis Manuel; Gagné, Dominic; Vigneault, Christian; Blondin, Patrick; Robert, Claude

    2014-11-01

    Mitochondria play an important role during early development in mammalian embryos. It has been shown that properly controlled follicular preparation increases the likelihood of in-vitro-produced bovine embryos reaching the blastocyst stage and that competent embryos exhibit heightened expression of genes associated with mitochondrial function. We hypothesized that apparently incompetent embryos could be rescued by restoring mitochondrial function. It has been shown that vitamin K2 (a membrane-bound electron carrier similar to ubiquinone) can restore mitochondrial dysfunction in eukaryotic cells. The aim of this study was therefore to investigate the effects of vitamin K2 on bovine embryonic development in vitro. The vitamin was found most effective when added 72 h after fertilization. It produced a significant (Pembryos of better morphological quality. It improved the mitochondrial activity significantly and had a measurable impact on gene expression. This is the first demonstration that current standard conditions of in vitro production of bovine embryos may be inadequate due to the lack of support for mitochondrial function and may be improved significantly by supplementing the culture medium with vitamin K2. © 2014 Society for Reproduction and Fertility.

  1. Studies on the cytodifferentiation of the neuroblasts and visual cells in the chick embryo retina, using the electron-microscopic autoradiography of 3H-thymidine

    International Nuclear Information System (INIS)

    Mishima, H.; Fujita, H.

    1978-01-01

    Studies on the histogenetic analysis of cytodifferentiation of the neuroblast and visual cell in the chick embryo retina were made using the autoradiography of 3 H-thymidine. The posterior pole region of the eyeball was observed in all the animals used. The retina in a 4-day-old chick embryo consists exclusively of matrix cells forming the matrix layer. In a 5-day-old chick embryo retina, neuroblasts first differentiated from the matrix cells migrate into the outer part of the matrix layer, forming the mantle layer. The matrix cell is a homogeneous epithelial cell containing abundant free ribosomes and a poorly developed cytoplasmic membrane system in the cytoplasm. The characteristic sign of differentiation of the neuroblast is an appearance of elements of rough-surfaced endoplasmic reticulum and an indentation of the nucleus. The primitive visual cell having just lost its ability to synthesize DNA appears just beneath the pigment epithelium in a 7-day-old chick embryo, and all the cells lying beneath the pigment epithelium lose the ability to synthesize DNA at 10 days of incubation. The cytoplasmic process of the matrix cell is in contact with the adjacent one, making an apicolateral junction. When the matrix cell loses its ability to synthesize DNA, a big tentlike process extending over the level of the apicolateral junction appears. This phenomenon is considered to be a sign of differentiation from matrix cell to primitive visual cell, and this big tentlike process containing 2 centrioles is a primordium of the inner segment of the visual cell. (orig.) [de

  2. Live embryo imaging to follow cell cycle and chromosomes stability after nuclear transfer.

    Science.gov (United States)

    Balbach, Sebastian T; Boiani, Michele

    2015-01-01

    Nuclear transfer (NT) into mouse oocytes yields a transcriptionally and functionally heterogeneous population of cloned embryos. Most studies of NT embryos consider only embryos at predefined key stages (e.g., morula or blastocyst), that is, after the bulk of reprogramming has taken place. These retrospective approaches are of limited use to elucidate mechanisms of reprogramming and to predict developmental success. Observing cloned embryo development using live embryo cinematography has the potential to reveal otherwise undetectable embryo features. However, light exposure necessary for live cell cinematography is highly toxic to cloned embryos. Here we describe a protocol for combined bright-field and fluorescence live-cell imaging of histone H2b-GFP expressing mouse embryos, to record cell divisions up to the blastocyst stage. This protocol, which can be adapted to observe other reporters such as Oct4-GFP or Nanog-GFP, allowed us to quantitatively analyze cleavage kinetics of cloned embryos.

  3. A New Cost-Effective Multi-Drive Solution based on a Two-Stage Direct Power Electronic Conversion Topology

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2002-01-01

    The matrix converter is a single stage AC/AC converter, which is able to provide sinusoidal PWM output voltages and input currents, inherent bi-directional power flow with no need of bulky DC-capacitors and large line inductors. However, the increased number of active switches (18) and the need...... for a reduction of power devices. In this paper, a new DPEC topology suited for multi-drive application is proposed, having an input port for a three-phase power supply and several output ports to connect three-phase loads, which are independently controlled. The cost of the rectification stage is therefore...... shared by many loads, making this topology more cost effective. The functionality of the proposed two-stage multi-drive direct power electronic conversion topology is validated by experiments on a realistic laboratory prototype....

  4. A New Cost-Effective Multi-Drive Solution based on a Two-Stage Direct Power Electronic Conversion Topology

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2002-01-01

    The matrix converter is a single stage AC/AC converter, which is able to provide sinusoidal PWM output voltages and input currents, inherent bi-directional power flow with no need of bulky DC-capacitors and large line inductors. However, the increased number of active switches (18) and the need o...... shared by many loads, making this topology more cost effective. The functionality of the proposed two-stage multi-drive direct power electronic conversion topology is validated by experiments on a realistic laboratory prototype.......The matrix converter is a single stage AC/AC converter, which is able to provide sinusoidal PWM output voltages and input currents, inherent bi-directional power flow with no need of bulky DC-capacitors and large line inductors. However, the increased number of active switches (18) and the need...... of a protection circuit involving twelve diodes with full voltage/current ratings used only during faulty situations, makes this topology not so attractive. Lately, two stage Direct Power Electronic Conversion (DPEC) topologies have been proposed, providing similar functionality as a matrix converter but allowing...

  5. Effects of alpha particles on zebrafish embryos

    International Nuclear Information System (INIS)

    Yum, E.H.W.; Choi, V.W.Y.; Yu, K.N.; Li, V.W.T.; Cheng, S.H.

    2008-01-01

    Full text: Ionizing radiation such as X-ray and alpha particles can damage cellular macromolecules, which can lead to DNA single- and double-strand breaks. In the present work, we studied the effects of alpha particles on dechorionated zebrafish embryos. Thin polyallyldiglycol carbonate (PADC) films with a thickness of 16 μm were prepared from commercially available PADC films (with thickness of 100 μm) by chemical etching and used as support substrates for holding zebrafish embryos for alpha-particle irradiation. These films recorded alpha-particle hit positions, quantified the number and energy of alpha particles actually incident on the embryo cells, and thus enabled the calculation of the dose absorbed by the embryo cells. Irradiation was made at 1.25 hours post fertilization (hpf) with various absorbed dose. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was performed on the embryos at different time stages after irradiation. Marked apoptosis was detected only in embryos at earlier time stages. The results showed that DNA double-strand break during zebrafish embryogenesis can be induced by alpha-particle irradiation, which suggests that zebrafish is a potential model for assessing the effects of alpha-particle radiation

  6. Development of the endolymphatic sac in chick embryos, with reference to the degradation of otoconia

    Science.gov (United States)

    Yoshihara, T.; Kaname, H.; Narita, N.; Ishii, T.; Igarashi, M.; Fermin, C. D.

    1992-01-01

    The endolymphatic sac of chick embryos (from embryonic day 7 to 1-day-old chicks) was studied light- and electron-microscopically. At stage 30-31 (embryonic day 7-7.5), the epithelial cells of the endolymphatic sac were cuboidal to columnar in shape. Microvilli were relatively well developed. The intercellular space was wide. In the endolymphatic space of the endolymphatic sac, varying shapes and sizes of otoconia-like bodies were often observed. Intracytoplasmic phagosomes containing these bodies were rarely found. After stage 37 (embryonic day 11), otoconia-like bodies in the endolymphatic sac decreased in number and size. They were almost the same as the otoconia in the macular organs, ultrastructurally. These findings indicate that the endolymphatic sac of the chick embryos may possess the function of otoconial degradation and removal of calcium from otoconia.

  7. Cyclic electron flow provides acclimatory plasticity for the photosynthetic machinery under various environmental conditions and developmental stages

    Directory of Open Access Journals (Sweden)

    Marjaana eSuorsa

    2015-09-01

    Full Text Available Photosynthetic electron flow operates in two modes, linear and cyclic. In cyclic electron flow (CEF, electrons are recycled around photosystem I. As a result, a transthylakoid proton gradient (ΔpH is generated, leading to the production of ATP without concomitant production of NADPH, thus increasing the ATP/NADPH ratio within the chloroplast. At least two routes for CEF exist: a PGR5-PGRL1–and a chloroplast NDH-like complex mediated pathway. This review focuses on recent findings concerning the characteristics of both CEF routes in higher plants, with special emphasis paid on the crucial role of CEF in under challenging environmental conditions and developmental stages.

  8. Design of a novel 5-DOF flexure-based compound alignment stage for Roll-to-Roll Printed Electronics.

    Science.gov (United States)

    Chen, Weihai; Yang, Shang; Liu, Jingmeng; Chen, Wenjie; Jin, Yan

    2017-02-01

    Alignment stage is a pivotal component for Roll-to-Roll Printed Electronic (R2RPE), especially for Roll-to-Roll inkjet printing. This paper presents the design, modeling, and testing of a new flexure-based compound alignment stage for R2RPE. In this design, the alignment stage has 5-DOF (Degree of Freedom) motions for compensating the alignment errors and only the rotation motion about the y-axis is redundant. The stage is constructed in series by four key parts and adopts a compounded flexure structure to achieve a great performance. Each part is driven by a piezoelectric actuator or voice coil motor actuator to obtain one or two DOF motion. In order to enlarge the travel range of the alignment stage, a Scott-Russell mechanism and a lever mechanism are arranged in series for forming a two-grade displacement amplifier to overcome the small displacement of the actuator. Based on the pseudo-rigid-body simplification method, alignment models are developed. Kinematic and static analyses are conducted to evaluate the performance of the stage in terms of travel range and input stiffness. Finite element simulation is carried out to examine the mechanical performance and the theoretical models. A prototype is fabricated and experiments are conducted. Results show that the proposed alignment stage possesses an error compensation workspace of 148.11μm×149.73μm×813.61μm×1.558mrad×3.501mrad with output coupling errors of 0.693% and 0.637% between the x- and y-axis, which meets the requirements of Roll-to-Roll inkjet printing.

  9. Labeling surface epitopes to identify Cryptosporidium life stages using a scanning electron microscopy-based immunogold approach.

    Science.gov (United States)

    Edwards, Hanna; Thompson, R C Andrew; Koh, Wan H; Clode, Peta L

    2012-02-01

    The Apicomplexan parasite Cryptosporidium parvum is responsible for the widespread disease cryptosporidiosis, in both humans and livestock. The nature of C. parvum infection is far from understood and many questions remain in regard to host-parasite interactions, limiting successful treatment of the disease. To definitively identify a range of C. parvum stages in cell culture and to begin to investigate host cell interactions in some of the lesser known life stages, we have utilized a combined scanning electron microscopy and immunolabeling approach, correlating high resolution microstructural information with definitive immunogold labeling of Cryptosporidium stages. Several life cycle stages, including oocysts, merozoites I, trophozoites, gamonts and microgametocytes, were successfully immunolabeled in an in vitro model system. Developing oocysts were clearly immunolabeled, but this did not persist once excystation had occurred. Immunolabeling visualized on the host cell surface adjacent to invasive merozoites is likely to be indicative of receptor shedding, with merozoites also initiating host responses that manifested as abnormal microvilli on the host cell surface. Small sub-micron stages such as microgametocytes, which were impossible to identify as single entities without immunolabeling, were readily visualized and observed to attach to host cells via novel membranous projections. Epicellular parasites also expressed Cryptosporidium-derived epitopes within their encapsulating membrane. These data have allowed us to confidently identify a variety of C. parvum stages in cell culture at high resolution. With this, we provide new insight into C. parvum - host cell interactions and highlight future opportunities for investigating and targeting receptor-mediated interactions between Cryptosporidium life cycle stages and host cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation

    Energy Technology Data Exchange (ETDEWEB)

    Shirakashi, Ryo, E-mail: aa21150@iis.u-tokyo.ac.jp [Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505 (Japan); Mischke, Miriam [Lehrstuhl fuer Biotechnologie und Biophysik, Biozentrum, Universitaet Wuerzburg, Wuerzburg (Germany); Fischer, Peter [Physiologische Chemie, Biozentrum, Universitaet Wuerzburg, Wuerzburg (Germany); Memmel, Simon [Lehrstuhl fuer Biotechnologie und Biophysik, Biozentrum, Universitaet Wuerzburg, Wuerzburg (Germany); Krohne, Georg [Abteilung fuer Elektronenmikroskopie, Biozentrum, Universitaet Wuerzburg, Wuerzburg (Germany); Fuhr, Guenter R. [Lehrstuhl fuer Biotechnologie und Medizintechnik, Universitaet des Saarlandes, Saarbruecken (Germany); Zimmermann, Heiko [Lehrstuhl fuer Molekulare und Zellulaere Biotechnologie, Universitaet des Saarlandes, Saarbruecken (Germany); Sukhorukov, Vladimir L., E-mail: sukhorukov@biozentrum.uni-wuerzburg.de [Lehrstuhl fuer Biotechnologie und Biophysik, Biozentrum, Universitaet Wuerzburg, Wuerzburg (Germany)

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer Electrorotation offers a non-invasive tool for dielectric analysis of fish embryos. Black-Right-Pointing-Pointer The three-shell dielectric model matches the rotation spectra of medaka eggs. Black-Right-Pointing-Pointer The capacitance value suggests a double-membrane structure of yolk envelope. -- Abstract: The Japanese medaka fish, Oryzias latipes, has become a powerful vertebrate model organism in developmental biology and genetics. The present study explores the dielectric properties of medaka embryos during pre-hatching development by means of the electrorotation (ROT) technique. Due to their layered structure, medaka eggs exhibited up to three ROT peaks in the kHz-MHz frequency range. During development from blastula to early somite stage, ROT spectra varied only slightly. But as the embryo progressed to the late-somite stage, the ROT peaks underwent significant changes in frequency and amplitude. Using morphological data obtained by light and electron microscopy, we analyzed the ROT spectra with a three-shell dielectric model that accounted for the major embryonic compartments. The analysis yielded a very high value for the ionic conductivity of the egg shell (chorion), which was confirmed by independent osmotic experiments. A relatively low capacitance of the yolk envelope was consistent with its double-membrane structure revealed by transmission electron microscopy. Yolk-free dead eggs exhibited only one co-field ROT peak, shifted markedly to lower frequencies with respect to the corresponding peak of live embryos. The dielectric data may be useful for monitoring the development and changes in fish embryos' viability/conditions in basic research and industrial aquaculture.

  11. Preimplantation development of embryos in women of advanced maternal age

    Directory of Open Access Journals (Sweden)

    O. V. Chaplia

    2014-04-01

    Full Text Available In order to reveal the influence of genetic component on the early embryo development, the retrospective study of morphokinetic characteristics of 717 embryos subjected to preimplantation genetic testing was conducted. Blastomere biopsy for FISH-based preimplantation genetic screening of 7 chromosomes was performed on the third day of culture, while embryo developmental potential and morphological features at the cleavage and blastulation stage were studied regarding maternal age particularly in the group of younger women and patients older than 36. Results of genetic testing revealed that euploid embryos rate gradually decreased with maternal age comprising 39.9% in young women group and 25.3% of specimen belonging to elder patients. At the cleavage stage, morphological characteristics of aneuploid and euploid embryos didn’t differ significantly regardless of the age of patients that could be accounted for the transcriptional silence of embryo genome till the third day of its development. However, in case of prolonged culture chromosomally balanced embryos rarely faced developmental arrest (in 7.9% and formed blastocysts half more frequently compared to aberrant embryos (respectively 75.6 versus 49.8%. Nevertheless, no substantial difference was found between blastocyst formation rate among embryos with similar genetic component regardless of the maternal age. Taking into consideration high rate of chromosomally unbalanced embryos specific to patients of advanced maternal age, the relative proportion of aneuplouid blastocysts was significantly higher in this group of embryos. Thus, without genetic screening there is a possibility of inaccurate selection of embryos for women of advanced reproductive age for transfer procedure even in case of prolonged culture. Consequently, increase of aneuploid embryos frequency associated with permanent preimplantation natural selection effectiveness along with the postimplantation natural selection failure

  12. Efficient somatic embryo production of Limau madu (Citrus ...

    African Journals Online (AJOL)

    fbn

    concentrations for producing cell suspension and somatic embryos of Limau madu (Citrus suhuiensis ... Citrus. The successful performance of all the stages of somatic embryogenesis has been reported, from the growth of embryogenic cells to embryo maturation in ..... line I and Cleopatra, line II and C. limonia L. Osbeck, cv.

  13. Fruit, seed and embryo development of different cassava (Manihot ...

    African Journals Online (AJOL)

    Fruit, seed and embryo developments of different cassava (Manihot esculenta Crantz) genotypes, as well as embryo rescue, were investigated. The fruits of three genotypes after uncontrolled open pollination presented the same progressive development with similar sizes at different stages. There are large differences in ...

  14. Nascent stages of DNA radiolysis: secondary electron and reactive ion induced damage

    International Nuclear Information System (INIS)

    Huels, M.A.

    2000-01-01

    Full text: It is by now well understood that most of the energy deposited in solids by ionizing radiation is converted within less than attoseconds into the production of ions, radicals, and ballistic low-energy secondary electrons. The latter are known to decompose small molecules even at electron energies well below molecular ionization thresholds regardless of molecular aggregation state, and have recently been shown to induce substantial yields of single and double strand breaks in supercoiled DNA. In that study, we found that the electron-energy dependent strand break yields have a strong maximum near 10 eV, which was attributed to the decomposition of transient molecular anion (TMA) states, i.e. resonances. The localization of these resonances on the different components of DNA leads to dissociations into anion and radical fragments within femtoseconds, where subsequent fragment reactions on similar timescales are thought to lead to the final observed DNA damage. In order to unravel this sequence of secondary electron and reactive ion induced events, and to better understand their fundamental reaction pathways, we have performed, and will present: (a) measurements of the basic mechanisms by which low-energy (0-30 eV) electrons induce damage to different components of DNA, e.g. H 2 0, deoxyribose analogs, bases, as well as other organic model systems, and (b) measurements of the basic reaction pathways by which some of the energetic ion fragments observed in (a) induce further damage in simple hydrocarbon films, as well as solids of DNA components, or their structural analogs. Our experiments show that: (i) for electron energies below 15 eV dissociative electron attachment (i.e. resonances) results in exocyclic and complex endocyclic bond cleavages in any of the molecular systems studied, leading to the formation of a vast variety of reactive radical and anion fragments, whereas above 15 eV electronic excitations and ionizations (nonresonant mechanisms) may

  15. Dynamic analysis of angiogenesis in transgenic zebrafish embryos using a 3D multilayer chip-based technology

    Science.gov (United States)

    Akagi, Jin; Zhu, Feng; Hall, Chris J.; Khoshmanesh, Khashayar; Kalantar-Zadeh, Kourosh; Mitchell, Arnan; Crosier, Kathryn E.; Crosier, Philip S.; Wlodkowic, Donald

    2013-03-01

    Transgenic zebrafish (Danio rerio) models of human diseases have recently emerged as innovative experimental systems in drug discovery and molecular pathology. None of the currently available technologies, however, allow for automated immobilization and treatment of large numbers of spatially encoded transgenic embryos during real-time developmental analysis. This work describes the proof-of-concept design and validation of an integrated 3D microfluidic chip-based system fabricated directly in the poly(methyl methacrylate) transparent thermoplastic using infrared laser micromachining. At its core, the device utilizes an array of 3D micro-mechanical traps to actively capture and immobilize single embryos using a low-pressure suction. It also features built-in piezoelectric microdiaphragm pumps, embryo trapping suction manifold, drug delivery manifold and optically transparent indium tin oxide (ITO) heating element to provide optimal temperature during embryo development. Furthermore, we present design of the proof-of-concept off-chip electronic interface equipped with robotic servo actuator driven stage, innovative servomotor-actuated pinch valves and miniaturized fluorescent USB microscope. Our results show that the innovative device has 100% embryo trapping efficiency while supporting normal embryo development for up to 72 hours in a confined microfluidic environment. We also present data that this microfluidic system can be readily applied to kinetic analysis of a panel of investigational anti-angiogenic agents in transgenic zebrafish Tg(fli1a:EGFP) line. The optical transparency and embryo immobilization allow for convenient visualization of developing vasculature patterns in response to drug treatment without the need for specimen re-positioning. The integrated electronic interfaces bring the Lab-on-a-Chip systems a step closer to realization of complete analytical automation.

  16. Learning to segment mouse embryo cells

    Science.gov (United States)

    León, Juan; Pardo, Alejandro; Arbeláez, Pablo

    2017-11-01

    Recent advances in microscopy enable the capture of temporal sequences during cell development stages. However, the study of such sequences is a complex task and time consuming task. In this paper we propose an automatic strategy to adders the problem of semantic and instance segmentation of mouse embryos using NYU's Mouse Embryo Tracking Database. We obtain our instance proposals as refined predictions from the generalized hough transform, using prior knowledge of the embryo's locations and their current cell stage. We use two main approaches to learn the priors: Hand crafted features and automatic learned features. Our strategy increases the baseline jaccard index from 0.12 up to 0.24 using hand crafted features and 0.28 by using automatic learned ones.

  17. Three-stage decoherence dynamics of an electron spin qubit in an optically active quantum dot

    Science.gov (United States)

    Bechtold, Alexander; Rauch, Dominik; Li, Fuxiang; Simmet, Tobias; Ardelt, Per-Lennart; Regler, Armin; Müller, Kai; Sinitsyn, Nikolai A.; Finley, Jonathan J.

    2015-12-01

    The control of solid-state qubits requires a detailed understanding of the decoherence mechanisms. Despite considerable progress in uncovering the qubit dynamics in strong magnetic fields, decoherence at very low magnetic fields remains puzzling, and the role of quadrupole coupling of nuclear spins is poorly understood. For spin qubits in semiconductor quantum dots, phenomenological models of decoherence include two basic types of spin relaxation: fast dephasing due to static but randomly distributed hyperfine fields (~2 ns) and a much slower process (>1 μs) of irreversible monotonic relaxation due either to nuclear spin co-flips or other complex many-body interaction effects. Here we show that this is an oversimplification; the spin qubit relaxation is determined by three rather than two distinct stages. The additional stage corresponds to the effect of coherent precession processes that occur in the nuclear spin bath itself, leading to a relatively fast but incomplete non-monotonic relaxation at intermediate timescales (~750 ns).

  18. Metabolite profiling of somatic embryos of Cyclamen persicum in comparison to zygotic embryos, endosperm and testa

    Directory of Open Access Journals (Sweden)

    Traud eWinkelmann

    2015-08-01

    Full Text Available Somatic embryogenesis has been shown to be an efficient in vitro plant regeneration system for many crops such as the important ornamental plant Cyclamen persicum, for which this regeneration pathway of somatic embryogenesis is of interest for the vegetative propagation of parental lines as well as elite plants. However, somatic embryogenesis is not commercially used in many crops due to several unsolved problems, such as malformations, asynchronous development, deficiencies in maturation and germination of somatic embryos. In contrast, zygotic embryos in seeds develop and germinate without abnormalities in most cases. Instead of time-consuming and labor-intensive experiments involving tests of different in vitro culture conditions and plant growth regulator supplements, we follow a more directed approach. Zygotic embryos served as a reference and were compared to somatic embryos in metabolomic analyses allowing the future optimization of the in vitro system. The aims of this study were to detect differences in the metabolite profiles of torpedo stage somatic and zygotic embryos of C. persicum. Moreover, major metabolites in endosperm and testa were identified and quantified.Two sets of extracts of two to four biological replicates each were analyzed. In total 52 metabolites were identified and quantified in the different tissues. One of the most significant differences between somatic and zygotic embryos was that the proline concentration in the zygotic embryos was about 40 times higher than that found in somatic embryos. Epicatechin, a scavenger for reactive oxygen species, was found in highest abundance in the testa. Sucrose, the most abundant metabolite was detected in significantly higher concentrations in zygotic embryos. Also, a yet unknown trisaccharide, was significantly enriched in zygotic embryos.

  19. Auger electron spectroscopy study of initial stages of oxidation in a copper - 19.6-atomic-percent-aluminum alloy

    Science.gov (United States)

    Ferrante, J.

    1973-01-01

    Auger electron spectroscopy was used to examine the initial stages of oxidation of a polycrystalline copper - 19.6 a/o-aluminum alloy. The growth of the 55-eV aluminum oxide peak and the decay of the 59-, 62-, and 937-eV copper peaks were examined as functions of temperature, exposure, and pressure. Pressures ranged from 1x10 to the minus 7th power to 0.0005 torr of O2. Temperatures ranged from room temperature to 700 C. A completely aluminum oxide surface layer was obtained in all cases. Complete disappearance of the underlying 937-eV copper peak was obtained by heating at 700 C in O2 at 0.0005 torr for 1 hr. Temperature studies indicated that thermally activated diffusion was important to the oxidation studies. The initial stages of oxidation followed a logarithmic growth curve.

  20. Direct observation of the growth of voids in multifilamentary superconducting materials via hot stage scanning electron microscopy

    International Nuclear Information System (INIS)

    Wang, J.L.F.; Holthuis, J.T.; Pickus, M.R.; Lindberg, R.W.

    1978-11-01

    The need for large high field magnetic devices has focused attention on multifilamentary superconductors based on A15 compounds such as Nb 3 Sn. The commercial bronze process for fabricating multifilamentary superconducting Nb 3 Sn wires was developed. A major problem is strain sensitivity when long reaction times are employed. An improved hot stage for the scanning electron microscope was constructed to study the formation of the A15 phase by solid state diffusion. The nucleation and growth of voids near the interface of the A15 phase (Nb 3 Sn) and matrix were observed, monitored, and recorded on video tape. Successive layers of material heated in the hot stage were subsequently removed and the new surfaces were re-examined, using SEM-EDX and optical microscopy, to confirm the fact that the observed porosity was indeed a bulk rather than a surface phenomenon. These voids are considered to be a primary cause for degrading the mechanical, thermal and superconducting properties

  1. Effect of culture medium volume and embryo density on early mouse embryonic development: tracking the development of the individual embryo.

    Science.gov (United States)

    Dai, Shan-Jun; Xu, Chang-Long; Wang, Jeffrey; Sun, Ying-Pu; Chian, Ri-Cheng

    2012-07-01

    To determine the optimal volume or density of embryos for the well-of-the-well (WOW) system in order to track the development of individual embryos and to determine whether the WOW system can reverse the negative impact of culturing embryos singly. (1) Mouse embryos (groups of nine at the 2-cell stage) were cultured in 6.25 μl, 12.50 μl, 25.00 μl and 50.00 μl of droplets of culture medium under paraffin oil; (2) Groups of three, six, nine and twelve embryos at the 2-cell stage were cultured in 50 μl of droplet of culture medium under paraffin oil; (3) Groups of nine embryos at the 2-cell stage were cultured in 50 μl of droplet under paraffin oil with or without nine micro-wells made on the bottom of the Petri dish into each of which were placed one of the nine embryos (WOW system). Also single 2-cell stage embryos was cultured individually in 5.5 μl of droplet of culture medium under paraffin oil with or without a single micro-well made on the bottom of the Petri dish (WOW system for single culture). At the end of culture, the percentages of blastocyst development, hatching and hatched blastocysts were compared in each group. The blastocysts were fixed for differential staining. The blastocyst development was significantly higher (P WOW system. The blastocyst development was not improved when single embryo cultured individually in a micro-well was compared to single embryo cultured individually without micro-well. The total cell numbers of blastocysts were significantly higher in group embryo culture than single embryo culture regardless of whether the WOW system was used. In addition, the total cell numbers of blastocysts were significantly higher (P WOW system than without. Group embryo culture is superior to single embryo culture for blastocyst development. The WOW system with 50 μl of droplet of culture medium can be used to track the individual development of embryo cultured in groups while preserving good embryonic development. The reduced

  2. Polyamine levels during the development of zygotic and somatic embryos of Pinus radiata

    Science.gov (United States)

    Rakesh Minocha; Dale R. Smith; Cathie Reeves; Kevin D. Steele; Subhash C. Minocha

    1999-01-01

    Changes in the cellular content of three polyamines (putrescine, spermidine and spermine) were compared at different stages of development in zygotic and somatic embryos of Pinus radiata D. Don. During embryo development, both the zygotic and the somatic embryos showed a steady increase in spermidine content, with either a small decrease or no...

  3. In vivo assay for the developmental competence of embryo-derived zebrafish cell lines

    NARCIS (Netherlands)

    Speksnijder, JE; Hage, WJ; Lanser, PH; Collodi, P; Zivkovic, D

    We have produced chimeric zebrafish embryos by transplanting permanent embryo-derived cell lines into blastula-stage embryos. Furthermore, we have established a fluorescent in vivo assay to monitor the developmental effects and fate of such transplanted cells using confocal laser scanning

  4. Polyamines and their biosynthetic enzymes during somatic embryo development in red spruce (Picea rubens Sarg.)

    Science.gov (United States)

    Rakesh Minocha; Subhash C. Minocha; Stephanie Long

    2004-01-01

    The major objective of this study was to determine if the observed changes in polyamines and their biosynthetic enzymes during somatic embryo development were specifically related to either the stage of the embryo development or to the duration of time spent on the maturation medium. Somatic embryos of red spruce (Picea rubens) at different...

  5. Activation of ribosomal RNA genes in porcine embryos produced in vitro or by somatic cell nuclear transfer

    DEFF Research Database (Denmark)

    Bjerregaard, Bolette; Pedersen, Hanne Gervi; Jakobsen, Anne Sørig

    2007-01-01

    equal proportions of transcriptionally active and inactive embryos and essentially all embryos that developed to the 16-cell stage (n = 21) and further to the blastocyst stage (n = 19) contained only transcriptionally active cells. In conclusion, porcine embryos produced in vitro had an asynchronous...

  6. Addition of ascorbate during cryopreservation stimulates subsequent embryo development.

    Science.gov (United States)

    Lane, Michelle; Maybach, Jeffery M; Gardner, David K

    2002-10-01

    Embryo development following cryopreservation is reduced compared with fresh embryos. One of the traumas that cryopreservation imparts on embryos is an increase in oxidative stress. Therefore, this study investigated the effects of the addition of the antioxidant ascorbate to the cryopreservation solutions on subsequent embryo development. Mouse embryos at the 2-cell and blastocyst stages were either slow-frozen or vitrified in solutions containing either no ascorbate or 0.1 or 0.5 mmol/l ascorbate. The effects on the levels of hydrogen peroxide and subsequent embryo development and physiology were assessed. Addition of ascorbate to the cryopreservation solutions reduced the levels of hydrogen peroxide in embryos. Furthermore, addition of 0.1 mmol/l ascorbate significantly enhanced inner cell mass development in blastocysts. Embryos cryopreserved with ascorbate had significantly lower levels of lactate dehydrogenase leakage, and increased rates of metabolism compared with those cryopreserved in the absence of ascorbate. The benefits of ascorbate were significantly greater in embryos that were slow-frozen compared with those that were vitrified. These data indicate that the addition of 0.1 mmol/l ascorbate to the cryopreservation solutions for the mammalian embryo would be of significant value.

  7. Transcriptome analysis of Anopheles stephensi embryo using ...

    Indian Academy of Sciences (India)

    2013-04-18

    Apr 18, 2013 ... SignalP/) (Nielsen et al. 1997). All ESTs are submitted in NCBI GenBank database ..... 2001). Expression of these genes hint at conserved pathways of epigenetic regulation associated with. GBR stage embryos. Developmental timing of gene expres- sion is regulated by a set of evolutionarily conserved.

  8. [Assisted reproductive technologies and the embryo status].

    Science.gov (United States)

    Englert, Y

    The status of the human embryo has always be a subject of philosophical and theological thoughts with major social consequences, but, until the 19th century, it has been mainly an abstraction. The arrival of the human embryo in vitro, materialized by Louise Brown's birth in 1978 and above all by the supernumerary embryos produced by the Australian team of Trounson and Wood following the introduction of ovarian stimulation, will turn theoretical thoughts into a reality. Nobody may ignore the hidden intentions behind the debate, as to recognise a status to a few days old embryo will immediately have a major impact on the status of a few weeks old foetus and therefore on the abortion rights. We will see that the embryo status, essentially based as well on a vision on the good and evil as on social order, cannot be based on a scientific analysis of the reproduction process but comes from a society's choice, by essence " arbitrary " and always disputable. This does not preclude the collectivity right and legitimacy to give a precise status and it is remarkable to observe the law is careful not to specify which status to give to the human embryo. It is more thru handling procedures and functioning rules that the law designed the embryo position, neither with a status of a person, nor of a thing. It nevertheless remains true that there is a constant risk that the legislation gives the embryo a status that would call into question it's unique characteristic of early reproductive stage, jeopardizing at once the hard-won reproductive freedom (reproductive choice) as well as freedom of research on embryonic stem cells, one of the most promising field of medical research.

  9. Structural Alterations of the Glomerular Wall And Vessels in Early Stages of Diabetes Mellitus: Light and Transmission Electron Microscopic Study

    Directory of Open Access Journals (Sweden)

    Dkhil MA

    2007-01-01

    Full Text Available Objective: The capillary changes at the initial stage of diabetes may show an angioarchitecture clearly different from those of later stages and,/or very severe glomerular change. However, the onset of alterations in the early phases is unclear. This study attempts to determine the functional and structural alterations of the glomerular wall and vesicles in the early stage of diabetes.Material and Methods: Twenty-five adult rats were used in this study. They were divided into two groups: the first group of five was used as a control .The second group of 20 (the experimental group was injected intraperitoneally by a single dose of streptozotocin to induce hyperglycemia. Rats were sacrificed after ten days, two months, and four months.Five rats at two months of age with hyperglycemia were treated with insulin for eight weeks. Renal tissues were prepared by routine technique for light and transmission electron microscopic evaluation. Results: By light microscopy after ten days of induced hyperglycemia, there were no structural modifications detected either in renal glomerular fine vessels or in the glomerular basement membrane of the glomerular capillaries. After two months, there was a moderate glomerular enlargement and dilatation of glomerular capillaries, afferent, and efferent arterioles. After four months, glomerular basement membrane thickening was the only structural alteration observed. Recovery of the glomerular alterations was observed after two months of treatment with insulin. Conclusion: In early stages of diabetes mellitus in rats, there was an increase in the diameter of glomerular vessels. In later stages of the disease, the reverse was seen, but insulin treatment had a positive role in reversing these changes in the study subjects.

  10. Characterization of the onset of embryonic control and early development in the bovine embryo

    International Nuclear Information System (INIS)

    Barnes, F.L.

    1988-01-01

    Bovine embryos were used to determine if morphological and molecular features of early development are similar to in vivo recovered bovine embryos and to determine at what level early bovine development is regulated. Radiolabeling of IVP embryos and in vivo recovered embryos with 35 S-methionine for SDS-polyacrylamide gel electrophoresis reveals that these embryos are equivalent. Few differences in protein profiles are observed between 1- and early 4-cell embryos. A change in protein profiles begins at the mid 4-cell stage and continues into the 8-cell stage. Few differences in protein profiles are observed between 1- and early 4-cell embryos. A change in protein profiles begins at the mid 4-cell stage and continues into the 8-cell stage. Few differences in protein profiles are observed between late 8-cells and morulae. This transition is α-amanitin sensitive therefore due to de novo embryonic transcription. Embryonic transcription is partially responsible for terminating the post-transcriptionally regulated period of early bovine development. Argentophillic nucleolar organizing regions (Ag-NORs) indicate onset of nucleolar activation. Ag-NORs were absent in 2- and 4-cell IVP embryos and rarely occurred in 8-cell IVP embryos cultured in vitro. IVP 1- and 2-cell embryos cultured to blastocysts in sheep oviducts demonstrated Ag-NORs. Thus the lack of nucleolar activation of IVP embryos cultured in vitro is culture induced between the 2- and 8-cell stage

  11. Studies of In Vitro Embryo Culture of Guppy (Poecilia reticulata).

    Science.gov (United States)

    Liu, LiLi; Lee, Ki-Young

    2014-09-01

    Different with other fishes, the guppies (Poecilia reticulata) is ovoviviparity, which retain their fertilized eggs within the follicle throughout gestation. The synchronously growing diplotene oocytes store nutrients in droplets and yolk, before their maturation and fertilization. The lecithotrophic strategy of development entails the provisioning of embryos with resources from the maternal yolk deposit rather than from a placenta, it allows the extracorporeal culture of guppy embryo. Studies on their early development of live bearers like the guppy including lineage tracing and genetic manipulations, have been limited. Therefore, to optimize conditions of embryo in vitro culture, explanted embryos from pregnant females were incubated in embryo medium (L-15 medium, supplemented with 5, 10, 15, 20% fetal bovine serum, respectively). We investigated whether the contents of FBS in vitro culture medium impact the development of embryos, and whether they would hatch in vitro. Our study found that in 5% of FBS of the medium, although embryos developed significantly slower in vitro than in the ovary, it was impossible to exactly quantify the developmental delay in culture, due to the obvious spread in developmental stage within each batch of eggs, and embryos can only be maintained until the early-eyed. And although in culture with 20% FBS the embryos can sustain rapid development of early stage, but cannot be cultured for the entire period of their embryonic development and ultimately died. In the medium with 10% and 15% FBS, the embryos seems well developed, even some can continue to grow after follicle ruptures until it can be fed. We also observed that embryonic in these two culture conditions were significantly different in development speed, in 15% it is faster than 10%. But 10% FBS appears to be more optimizing condition than 15% one on development process of embryos and survival rate to larvae stage.

  12. Dose estimation in embryo or fetus in external fields

    International Nuclear Information System (INIS)

    Gregori, Beatriz N.

    2001-01-01

    The embryo or the fetus can be irradiated as result of radiological procedures of diagnosis of therapy in where the beam effects directly on the same one or in tissues or peripherical organs. Some authors have suggested that in the first stages of the pregnancy the dose in ovaries can be the good estimated of the dose in embryo or fetus. In advanced conditions of the development, probably also in the early stage, is more appropriated to specify the dose in the embryo or fetus equal of the uterus. The dose in the uterus is a good estimated so much for external irradiation as for radionuclides incorporation

  13. Perkembangan Praimplantasi Embrio Mencit dengan Materi Genetik yang Berasal dari Parental, Maternal, dan Inti Sel Somatik (PRE-IMPLANTATION DEVELOPMENT OF MOUSE EMBRYO WITH GENETIC MATERIAL DERIVED FROM PARENTAL, MATERNAL AND SOMATIC CELL NUCLEUS

    Directory of Open Access Journals (Sweden)

    Harry Murti

    2014-05-01

    Full Text Available Cloned embryo and parthenogenetic embryo are a potential source of stem cells for regenerativemedicine. Stem cells derived from those embryos are expected to overcome the ethical issues to the use offertilization embryos for therapeutic purposes. The pre-implantation development is a critical step fordeveloping embryos reach the blastocyst stage. The objectives in vivo of this research are to produce mousecloned embryo, parthenogenetic embryo, and fertilized embryo and to study stages of  in vitro pre-implantation development culture. In vivo fertilized embryos, mouse oocytes, and cumulus cells were usedin this study. Treatment was performed on female mice superovulated with PMSG and hCG injections.Two-cell stage of in vivo fertilized embryos were collected on the second day post hCG injection. Clonedembryos were produced through Somatic Cell Nuclear Transfer (SCNT, which included enucleation, nucleartransfer and artificial activation. Parthenogenetic embryos were produced with artificial activationtechnique. The result of the research indicated that SCNT application was able to produce cloned embryos which could develop to blastocyst stage (3,2%. In addition, artificial activation of oocytes could produceparthenogenetic embryos which were able to develop up to the blastocyst stage (8,6%. In conclusion,efficiency level of parthenogenetic embryos that is able to reach the blastocyst stage was higher than in thecloned embryos. Fertilized embryos shows a better development and more efficient compared to in vitrocloned embryos and parthenogenetic embryos cultures.

  14. Analysis of compaction initiation in human embryos by using time-lapse cinematography.

    Science.gov (United States)

    Iwata, Kyoko; Yumoto, Keitaro; Sugishima, Minako; Mizoguchi, Chizuru; Kai, Yoshiteru; Iba, Yumiko; Mio, Yasuyuki

    2014-04-01

    To analyze the initiation of compaction in human embryos in vitro by using time-lapse cinematography (TLC), with the goal of determining the precise timing of compaction and clarifying the morphological changes underlying the compaction process. One hundred and fifteen embryos donated by couples with no further need for embryo-transfer were used in this study. Donated embryos were thawed and processed, and then their morphological behavior during the initiation of compaction was dynamically observed via time-lapse cinematography (TLC) for 5 days. Although the initiation of compaction occurred throughout the period from the 4-cell to 16-cell stage, 99 (86.1 %) embryos initiated compaction at the 8-cell stage or later, with initiation at the 8-cell stage being most frequent (22.6 %). Of these 99 embryos, 49.5 % developed into good-quality blastocysts. In contrast, of the 16 (13.9 %) embryos that initiated compaction prior to the 8-cell stage, only 18.8 % developed into good-quality blastocysts. Embryos that initiated compaction before the 8-cell stage showed significantly higher numbers of multinucleated blastomeres, due to asynchronism in nuclear division at the third mitotic division resulting from cytokinetic failure. The initiation of compaction primarily occurs at the third mitotic division or later in human embryos. Embryos that initiate compaction before the 8-cell stage are usually associated with aberrant embryonic development (i.e., cytokinetic failure accompanied by karyokinesis).

  15. Effect of electron beam irradiation on developmental stages of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Kim, Junheon; Chung, Soon-Oh; Jang, Sin Ae; Jang, Miyeon; Park, Chung Gyoo

    2015-07-01

    Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is an economically important and polyphagous pest, which harms various kinds of food crops and important agricultural plants, such as cotton and paprika. Effects of electron beam irradiation at six dose levels between 50 and 350 Gy on the egg (24-48 h old), the larval (4-5th instar), and the pupal (7-d old for female, 5-d old for male) development, and on the adult (1-d old) reproduction were tested to identify a potential quarantine treatment dose. Increased doses of irradiation on eggs decreased egg hatchability, pupation and adult emergence and increased larval period. ED99 values for inhibition of hatching, pupation and emergence were 460.6, 236.9 and 197.8 Gy, respectively. When larvae were irradiated with more than 280 Gy, no larvae could develop into pupae. ED99 values for inhibition of pupation and adult emergence were 265.6 and 189.6 Gy, respectively. Even though the irradiation on pupa did not completely inhibit adult emergence, most of the pupae emerged to deformed adults. When adults were irradiated, fecundity was not affected. However, F1 egg hatching was completely inhibited at the dose of 350 Gy. ED99 value for inhibition of adult emergence was estimated at 366.5 Gy. Our results suggest that electron beam irradiation could be recommendable as an alternative to MB and as a phytosanitary treatment for quarantine. A treatment dose of less than or equal to 220 Gy is suggested as a potential quarantine treatment to H. armigera egg for prevention of pupation and to larva for prevention of adult emerge.

  16. Effect of supplementation of different growth factors in embryo culture medium with a small number of bovine embryos on in vitro embryo development and quality.

    Science.gov (United States)

    Ahumada, C J; Salvador, I; Cebrian-Serrano, A; Lopera, R; Silvestre, M A

    2013-03-01

    When embryos are cultured individually or in small groups, blastocyst yield efficiency and quality are usually reduced. The aim of this work was to investigate the effect of supplementation of the embryo culture medium (CM) with several growth factors (GFs) on embryo development and apoptosis rate when a reduced number of embryos were in vitro cultured. Two experimental studies (ES) were carried out. In ES 1, five treatments were tested to study the effect of GF on embryo development: Control (∼30 to 50 embryos cultured in 500 μl of CM); Control 5 (Five embryos cultured in 50 μl microdrops of CM), without addition of GF in either of the two control groups; epidermal GF (EGF); IGF-I; and transforming GF-α (TGF-α) (Five embryos were cultured in 50 μl microdrops of CM with 10 ng/ml EGF, 10 ng/ml IGF-I or 10 ng/ml TGF-α, respectively). In ES 2, following the results obtained in ES 1, four different treatments were tested to study their effect on embryo development and quality (number of cells per blastocyst and apoptotic rate): Control; Control 5; EGF, all three similar to ES 1; EGF + IGF-I group (five embryos cultured in 50 μl microdrops of CM with 10 ng/ml EGF and 10 ng/ml IGF-I). In both ESs, it was observed that a higher proportion of embryos cultured in larger groups achieved blastocyst stage than embryos cultured in reduced groups (22.6% v. 14.0%, 12.6% and 5.3% for Control v. Control 5, IGF-I, TGF-α groups in ES 1, and 24.9% v. 17.1% and 19.0% for Control v. Control 5 and EGF in ES 2, respectively; P embryos cultured in medium supplemented with EGF (18.5%) or with EGF + IGF-I (23.5%), in ES 1 and ES 2, respectively. With regard to blastocyst quality, embryos cultured in reduced groups and supplemented with EGF, alone or combined with IGF-I, presented lower apoptosis rates than embryos cultured in reduced groups without GF supplementation (11.6% and 10.5% v. 21.9% for EGF, EGF + IGF-I and Control 5 groups, respectively; P embryos, increasing blastocyst

  17. Embryo-maternal communication

    DEFF Research Database (Denmark)

    Østrup, Esben; Hyttel, Poul; Østrup, Olga

    2011-01-01

    Communication during early pregnancy is essential for successful reproduction. In this review we address the beginning of the communication between mother and developing embryo; including morphological and transcriptional changes in the endometrium as well as epigenetic regulation mechanisms dire...... directing the placentation. An increasing knowledge of the embryo-maternal communication might not only help to improve the fertility of our farm animals but also our understanding of human health and reproduction.......Communication during early pregnancy is essential for successful reproduction. In this review we address the beginning of the communication between mother and developing embryo; including morphological and transcriptional changes in the endometrium as well as epigenetic regulation mechanisms...

  18. Staging of Alzheimer's Pathology in Triple Transgenic Mice: A Light and Electron Microscopic Analysis

    Directory of Open Access Journals (Sweden)

    Kwang-Jin Oh

    2010-01-01

    , and TauP301L gene mutations, remains unclear. At 3 weeks of age, AT180, Alz50, MC1, AT8, and PHF-1 intraneuronal immunoreactivity appeared in the amygdala and hippocampus and at later ages in the cortex of 3xTg-AD mice. AT8 and PHF-1 staining was fixation dependent in young mutant mice. 6E10 staining was seen at all ages. Fluorescent immunomicroscopy revealed CA1 neurons dual stained for 6E10 and Alz50 and single Alz50 immunoreactive neurons in the subiculum at 3 weeks and continuing to 20 months. Although electron microscopy confirmed intraneuronal cytoplasmic Alz50, AT8, and 6E10 reaction product in younger 3xTg-AD mice, straight filaments appeared at 23 months of age in female mice. The present data suggest that other age-related biochemical mechanisms in addition to early intraneuronal accumulation of 6E10 and tau underlie the formation of tau filaments in 3xTg-AD mice.

  19. Embryo fossilization is a biological process mediated by microbial biofilms.

    Science.gov (United States)

    Raff, Elizabeth C; Schollaert, Kaila L; Nelson, David E; Donoghue, Philip C J; Thomas, Ceri-Wyn; Turner, F Rudolf; Stein, Barry D; Dong, Xiping; Bengtson, Stefan; Huldtgren, Therese; Stampanoni, Marco; Chongyu, Yin; Raff, Rudolf A

    2008-12-09

    Fossilized embryos with extraordinary cellular preservation appear in the Late Neoproterozoic and Cambrian, coincident with the appearance of animal body fossils. It has been hypothesized that microbial processes are responsible for preservation and mineralization of organic tissues. However, the actions of microbes in preservation of embryos have not been demonstrated experimentally. Here, we show that bacterial biofilms assemble rapidly in dead marine embryos and form remarkable pseudomorphs in which the bacterial biofilm replaces and exquisitely models details of cellular organization and structure. The experimental model was the decay of cleavage stage embryos similar in size and morphology to fossil embryos. The data show that embryo preservation takes place in 3 distinct steps: (i) blockage of autolysis by reducing or anaerobic conditions, (ii) rapid formation of microbial biofilms that consume the embryo but form a replica that retains cell organization and morphology, and (iii) bacterially catalyzed mineralization. Major bacterial taxa in embryo decay biofilms were identified by using 16S rDNA sequencing. Decay processes were similar in different taphonomic conditions, but the composition of bacterial populations depended on specific conditions. Experimental taphonomy generates preservation states similar to those in fossil embryos. The data show how fossilization of soft tissues in sediments can be mediated by bacterial replacement and mineralization, providing a foundation for experimentally creating biofilms from defined microbial species to model fossilization as a biological process.

  20. Elongated microvilli support the sea urchin embryo concentrically within the perivitelline space until hatching.

    Science.gov (United States)

    Spiegel, Evelyn; Howard, Louisa; Spiegel, Melvin

    1989-06-01

    The early sea urchin embryo is supported in a concentric position within the perivitelline space by elongated microvilli which are attached to the fertilization envelope by extracellular matrix fibers. This "attachment complex," of microvillus tip: extracellular matrix fibers: fertilization envelope, was revealed by two methods: the use of pronase or calcium-free sea water to dissolve the extracellular matrix fibers, thus causing the eggs to lose their concentric location, and the visualization of the "attachment complex" using video-enhanced differential interference contrast microscopy and transmission electron microscope images. The presence of the "attachment complex" helps in understanding two types of early developmental events: (1) the apparently continual change in microvillus length during cleavage stages which retains the embryos in their concentric position and (2) the hatching process.

  1. Nucleolar development and allocation of key nucleolar proteins require de novo transcription in bovine embryos

    DEFF Research Database (Denmark)

    Svarcova, Olga; Laurincik, Jozef; Avery, Birthe

    2007-01-01

    The goal of the present study was to investigate whether key nucleolar proteins involved in ribosomal RNA (rRNA) transcription and processing are transcribed de novo or from maternally inherited messenger RNAs (mRNA) in bovine embryos, and to which extent de novo transcription of these proteins m......RNA is required for the development of functional nucleoli during the major activation of the embryonic genome. Immunofluorescence for localization of key nucleolar proteins, autoradiography for detection of transcriptional activity, and transmission electron microscopy were applied to in vitro produc ed bovine...... embryos cultured from the 2-cell stage with or without (control groups) a-amanitin, which blocks the RNA plymerases II and III transcription and, thus the synthesis of mRNA. In the control groups, weak autoradiographic labelling was initially observed in the periphery of few nuclei at the 4-cell...

  2. Improving initiation, genotype capture, and family representation in somatic embryogenesis of Pinus radiata by a combination of zygotic embryo maturity, media, and explant preparation

    DEFF Research Database (Denmark)

    Hargreaves, Cathy; Find, Jens; Reeves, Cathie

    2009-01-01

    . Optimum stage of cone maturity for initiation success was tested by five collections made at 1 week intervals, spanning the developmental period from pro-embryo to cotyledonary embryos. Two media were compared; embryo-development media (EDM6) and a modified Litvay medium (Glitz). Two zygotic embryo...

  3. Post-surgical treatment of early-stage breast cancer with electronic brachytherapy: an intersociety, multicenter brachytherapy trial

    Directory of Open Access Journals (Sweden)

    Peter D Beitsch

    2010-10-01

    Full Text Available Peter D Beitsch1, Rakesh R Patel2, John D Lorenzetti3, James C Wurzer4, James C Tucker5, Susan J Laduzinsky6, Morris A Kugler71Dallas Surgical Group, Dallas, TX, USA; 2Valley Medical Oncology Consultants, Pleasanton, CA, USA; 3Breast Specialists, Egg Harbor Township, NJ, USA; 4AtlantiCare Regional Medical Center, Egg Harbor Township, NJ, USA; 5DCH Regional Medical Center – Tuscaloosa, AL, USA; 6Memorial and St Elizabeth’s Cancer Treatment Center, Swansea, IL, USA; 7Southern Illinois Surgical Consultants, Maryville, IL, USAIntroduction: Electronic brachytherapy (EBT was developed to allow accelerated partial breast irradiation to be performed in a patient procedure room with minimal shielding. This observational, nonrandomized, multicenter study evaluated EBT as a post-surgical adjuvant radiation therapy for early stage breast cancer.Methods: This study included women aged 50 years or more with invasive carcinoma or ductal carcinoma in situ, tumor size ≤3 cm, negative lymph node status, and negative surgical margins. The endpoints were skin and subcutaneous toxicities, efficacy outcomes, cosmetic outcomes, and device performance. In this interim report, 1-month, 6-month, and 1-year follow-up data are available on 68, 59, and 37 patients, respectively.Results: The EBT device performed consistently, delivering the prescribed 34 Gy to all 69 patients (10 fractions/patient. Most adverse events were Grade 1 and included firmness, erythema, breast tenderness, hyperpigmentation, pruritis, field contracture, seroma, rash/desquamation, palpable mass, breast edema, hypopigmentation, telangiectasia, and blistering, which were anticipated. Breast infection occurred in 2 (2.9% patients. No tumor recurrences were reported. Cosmetic outcomes were excellent or good in 83.9%–100% of evaluable patients at 1 month, 6 months, and 1 year.Conclusion: This observational, nonrandomized, multicenter study demonstrates that this EBT device was reliable and well

  4. Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation

    International Nuclear Information System (INIS)

    Shirakashi, Ryo; Mischke, Miriam; Fischer, Peter; Memmel, Simon; Krohne, Georg; Fuhr, Günter R.; Zimmermann, Heiko; Sukhorukov, Vladimir L.

    2012-01-01

    Highlights: ► Electrorotation offers a non-invasive tool for dielectric analysis of fish embryos. ► The three-shell dielectric model matches the rotation spectra of medaka eggs. ► The capacitance value suggests a double-membrane structure of yolk envelope. -- Abstract: The Japanese medaka fish, Oryzias latipes, has become a powerful vertebrate model organism in developmental biology and genetics. The present study explores the dielectric properties of medaka embryos during pre-hatching development by means of the electrorotation (ROT) technique. Due to their layered structure, medaka eggs exhibited up to three ROT peaks in the kHz–MHz frequency range. During development from blastula to early somite stage, ROT spectra varied only slightly. But as the embryo progressed to the late-somite stage, the ROT peaks underwent significant changes in frequency and amplitude. Using morphological data obtained by light and electron microscopy, we analyzed the ROT spectra with a three-shell dielectric model that accounted for the major embryonic compartments. The analysis yielded a very high value for the ionic conductivity of the egg shell (chorion), which was confirmed by independent osmotic experiments. A relatively low capacitance of the yolk envelope was consistent with its double-membrane structure revealed by transmission electron microscopy. Yolk-free dead eggs exhibited only one co-field ROT peak, shifted markedly to lower frequencies with respect to the corresponding peak of live embryos. The dielectric data may be useful for monitoring the development and changes in fish embryos’ viability/conditions in basic research and industrial aquaculture.

  5. Label-free Quantification of Proteins in Single Embryonic Cells with Neural Fate in the Cleavage-Stage Frog (Xenopus laevis) Embryo using Capillary Electrophoresis Electrospray Ionization High-Resolution Mass Spectrometry (CE-ESI-HRMS).

    Science.gov (United States)

    Lombard-Banek, Camille; Reddy, Sushma; Moody, Sally A; Nemes, Peter

    2016-08-01

    Quantification of protein expression in single cells promises to advance a systems-level understanding of normal development. Using a bottom-up proteomic workflow and multiplexing quantification by tandem mass tags, we recently demonstrated relative quantification between single embryonic cells (blastomeres) in the frog (Xenopus laevis) embryo. In this study, we minimize derivatization steps to enhance analytical sensitivity and use label-free quantification (LFQ) for single Xenopus cells. The technology builds on a custom-designed capillary electrophoresis microflow-electrospray ionization high-resolution mass spectrometry platform and LFQ by MaxLFQ (MaxQuant). By judiciously tailoring performance to peptide separation, ionization, and data-dependent acquisition, we demonstrate an ∼75-amol (∼11 nm) lower limit of detection and quantification for proteins in complex cell digests. The platform enabled the identification of 438 nonredundant protein groups by measuring 16 ng of protein digest, or embryo. LFQ intensity was validated as a quantitative proxy for protein abundance. Correlation analysis was performed to compare protein quantities between the embryo and n = 3 different single D11 blastomeres, which are fated to develop into the nervous system. A total of 335 nonredundant protein groups were quantified in union between the single D11 cells spanning a 4 log-order concentration range. LFQ and correlation analysis detected expected proteomic differences between the whole embryo and blastomeres, and also found translational differences between individual D11 cells. LFQ on single cells raises exciting possibilities to study gene expression in other cells and models to help better understand cell processes on a systems biology level. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Label-free Quantification of Proteins in Single Embryonic Cells with Neural Fate in the Cleavage-Stage Frog (Xenopus laevis) Embryo using Capillary Electrophoresis Electrospray Ionization High-Resolution Mass Spectrometry (CE-ESI-HRMS)*

    Science.gov (United States)

    Lombard-Banek, Camille; Reddy, Sushma; Moody, Sally A.; Nemes, Peter

    2016-01-01

    Quantification of protein expression in single cells promises to advance a systems-level understanding of normal development. Using a bottom-up proteomic workflow and multiplexing quantification by tandem mass tags, we recently demonstrated relative quantification between single embryonic cells (blastomeres) in the frog (Xenopus laevis) embryo. In this study, we minimize derivatization steps to enhance analytical sensitivity and use label-free quantification (LFQ) for single Xenopus cells. The technology builds on a custom-designed capillary electrophoresis microflow-electrospray ionization high-resolution mass spectrometry platform and LFQ by MaxLFQ (MaxQuant). By judiciously tailoring performance to peptide separation, ionization, and data-dependent acquisition, we demonstrate an ∼75-amol (∼11 nm) lower limit of detection and quantification for proteins in complex cell digests. The platform enabled the identification of 438 nonredundant protein groups by measuring 16 ng of protein digest, or embryo. LFQ intensity was validated as a quantitative proxy for protein abundance. Correlation analysis was performed to compare protein quantities between the embryo and n = 3 different single D11 blastomeres, which are fated to develop into the nervous system. A total of 335 nonredundant protein groups were quantified in union between the single D11 cells spanning a 4 log-order concentration range. LFQ and correlation analysis detected expected proteomic differences between the whole embryo and blastomeres, and also found translational differences between individual D11 cells. LFQ on single cells raises exciting possibilities to study gene expression in other cells and models to help better understand cell processes on a systems biology level. PMID:27317400

  7. A cutin fluorescence pattern in developing embryos of some angiosperms

    Directory of Open Access Journals (Sweden)

    Ewa Szczuka

    2014-01-01

    Full Text Available A cuticle visualized by auramine O fluorescence appears on the developing embryos of 9 species belonging to Cruciferae, Caryophyllaceae, Plantaginaceae, Linaceae and Papilionaceae. In the investigated species the formation and extent of fluorescing and non-fluorescing embryonic areas follow a similar pattern. At first the cutin fluorescing layer is formed on the apical part of the proembryo without delimited protoderm. This layer extends and at the late globular stage envelops the embryo proper, except for a cell adjoining the suspensor. Fluorescing cutin persists during the heart stage but disappears from the torpedo embryo. During these stages there is no cutine fluorescence on suspensorial cells. Continuous cutin fluorescence appears again on the surface of the whole embryo by the late torpedo stage. Then fluorescence disappears from the radicular part of U-shaped embryos, but persists on the shoot apex, cotyledons and at least on the upper part of hypocotyl. It is assumed that polarization and nutrition of the embryo may be influenced by cuticular changes.

  8. Selfed embryo death in Pinus taeda: a phenotypic profile.

    Science.gov (United States)

    Williams, Claire G

    2008-01-01

    Selective elimination of selfed embryos, or inbreeding depression, is shared among many members of the Pinaceae but it has not been fully characterized at the phenotypic level. Here, two death pattern model hypotheses are tested using 10 621 Pinus taeda embryos sampled in two cohorts. Cones from a single pedigree based on selfed, outbred, parent-offspring and offspring-parent matings were destructively sampled weekly before, during and after fertilization. Selfed embryo deaths adhered to two patterns over the course of development: death was linear with respect to days from fertilization; and a stage-specific death peak occurred during the early embryogeny stage. This death peak occurred from 23 to 36 d after fertilization in the 2004 cohort and from 27 to 34 d after fertilization in the 2006 cohort. Of those selfed embryos that died, 64-83% died at stages where a single dominant embryo was elongating inside the female gametophyte. Additional genetic models are needed to account for the stage-specific death component of selfed P. taeda embryos.

  9. Culture of bovine embryos on a polydimethylsiloxane (PDMS) microwell plate.

    Science.gov (United States)

    Akagi, Satoshi; Hosoe, Misa; Matsukawa, Kazutsugu; Ichikawa, Akihiko; Tanikawa, Tamio; Takahashi, Seiya

    2010-08-01

    We fabricated a polydimethylsiloxane (PDMS)-based microwell plate (PDMS-MP) containing 100 microwells with a rounded bottom and examined whether it can be used for culture of individual in vitro fertilized (IVF) embryos or parthenogenetically activated zona-free embryos in cattle. In Experiment 1, we examined the in vitro developmental ability of IVF embryos cultured individually on PDMS-MP. After IVF, 20 embryos were transferred into 100 microl drops on PDMS-MP and cultured individually in each well of PDMS-MP (PDMS group). After 7 days of culture, the embryos in the PDMS group developed to the blastocyst stage at the same rate of those in the control group cultured in a group of 20 embryos without PDMS-MP. There were no differences in total number of cells and the ratio of inner cell mass to total cells between the PDMS and control groups. In Experiment 2, we examined the in vitro developmental ability of parthenogenetically activated zona-free bovine embryos cultured individually on PDMS-MP. The zona-free embryos were cultured individually in each well of a PDMS-MP or in each well produced by pressing a darning needle onto the bottom of a culture dish (WOW group). After 7 days of culture, the blastocyst formation rate and cell number of blastocysts in the PDMS group did not differ from those of the zona-intact embryos in the control group. Also, there were no differences in the blastocyst formation rate and cell number of blastocysts between the WOW and PDMS groups. These results suggest that the culture system using PDMS-MP is useful for individual embryos or zona-free embryos in cattle.

  10. Equine cloning: in vitro and in vivo development of aggregated embryos.

    Science.gov (United States)

    Gambini, Andrés; Jarazo, Javier; Olivera, Ramiro; Salamone, Daniel F

    2012-07-01

    The production of cloned equine embryos remains highly inefficient. Embryo aggregation has not yet been tested in the equine, and it might represent an interesting strategy to improve embryo development. This study evaluated the effect of cloned embryo aggregation on in vitro and in vivo equine embryo development. Zona-free reconstructed embryos were individually cultured in microwells (nonaggregated group) or as 2- or 3-embryo aggregates (aggregated groups). For in vitro development, they were cultured until blastocyst stage and then either fixed for Oct-4 immunocytochemical staining or maintained in in vitro culture where blastocyst expansion was measured daily until Day 17 or the day on which they collapsed. For in vivo assays, Day 7-8 blastocysts were transferred to synchronized mares and resultant vesicles, and cloned embryos were measured by ultrasonography. Embryo aggregation improved blastocyst rates on a per well basis, and aggregation did not imply additional oocytes to obtain blastocysts. Embryo aggregation improved embryo quality, nevertheless it did not affect Day 8 and Day 16 blastocyst Oct-4 expression patterns. Equine cloned blastocysts expanded and increased their cell numbers when they were maintained in in vitro culture, describing a particular pattern of embryo growth that was unexpectedly independent of embryo aggregation, as all embryos reached similar size after Day 7. Early pregnancy rates were higher using blastocysts derived from aggregated embryos, and advanced pregnancies as live healthy foals also resulted from aggregated embryos. These results indicate that the strategy of aggregating embryos can improve their development, supporting the establishment of equine cloned pregnancies.

  11. Early embryo development in Fucus distichus is auxin sensitive

    Science.gov (United States)

    Basu, Swati; Sun, Haiguo; Brian, Leigh; Quatrano, Ralph L.; Muday, Gloria K.

    2002-01-01

    Auxin and polar auxin transport have been implicated in controlling embryo development in land plants. The goal of these studies was to determine if auxin and auxin transport are also important during the earliest stages of development in embryos of the brown alga Fucus distichus. Indole-3-acetic acid (IAA) was identified in F. distichus embryos and mature tissues by gas chromatography-mass spectroscopy. F. distichus embryos accumulate [(3)H]IAA and an inhibitor of IAA efflux, naphthylphthalamic acid (NPA), elevates IAA accumulation, suggesting the presence of an auxin efflux protein complex similar to that found in land plants. F. distichus embryos normally develop with a single unbranched rhizoid, but growth on IAA leads to formation of multiple rhizoids and growth on NPA leads to formation of embryos with branched rhizoids, at concentrations that are active in auxin accumulation assays. The effects of IAA and NPA are complete before 6 h after fertilization (AF), which is before rhizoid germination and cell division. The maximal effects of IAA and NPA are between 3.5 and 5 h AF and 4 and 5.5 h AF, respectively. Although, the location of the planes of cell division was significantly altered in NPA- and IAA-treated embryos, these abnormal divisions occurred after abnormal rhizoid initiation and branching was observed. The results of this study suggest that auxin acts in the formation of apical basal patterns in F. distichus embryo development.

  12. Storage oil breakdown during embryo development of Brassica napus (L.).

    Science.gov (United States)

    Chia, Tansy Y P; Pike, Marilyn J; Rawsthorne, Stephen

    2005-05-01

    In this study it is shown that at least 10% of the major storage product of developing embryos of Brassica napus (L.), triacylglycerol, is lost during the desiccation phase of seed development. The metabolism of this lipid was studied by measurements of the fate of label from [1-(14)C]decanoate supplied to isolated embryos, and by measurements of the activities of enzymes of fatty acid catabolism. Measurements on desiccating embryos have been compared with those made on embryos during lipid accumulation and on germinating seedlings. Enzymes of beta-oxidation and the glyoxylate cycle, and phosphoenolpyruvate carboxykinase were present in embryos during oil accumulation, and increased in activity and abundance as the seeds matured and became desiccated. Although the activities were less than those measured during germination, they were at least comparable to the in vivo rate of fatty acid synthesis in the embryo during development. The pattern of labelling, following metabolism of decanoate by isolated embryos, indicated a much greater involvement of the glyoxylate cycle during desiccation than earlier in oil accumulation, and showed that much of the (14)C-label from decanoate was released as CO(2) at both stages. Sucrose was not a product of decanoate metabolism during embryo development, and therefore lipid degradation was not associated with net gluconeogenic activity. These observations are discussed in the context of seed development, oil yield, and the synthesis of novel fatty acids in plants.

  13. Experimental taphonomy shows the feasibility of fossil embryos.

    Science.gov (United States)

    Raff, Elizabeth C; Villinski, Jeffrey T; Turner, F Rudolf; Donoghue, Philip C J; Raff, Rudolf A

    2006-04-11

    The recent discovery of apparent fossils of embryos contemporaneous with the earliest animal remains may provide vital insights into the metazoan radiation. However, although the putative fossil remains are similar to modern marine animal embryos or larvae, their simple geometric forms also resemble other organic and inorganic structures. The potential for fossilization of animals at such developmental stages and the taphonomic processes that might affect preservation before mineralization have not been examined. Here, we report experimental taphonomy of marine embryos and larvae similar in size and inferred cleavage mode to presumptive fossil embryos. Under conditions that prevent autolysis, embryos within the fertilization envelope can be preserved with good morphology for sufficiently long periods for mineralization to occur. The reported fossil record exhibits size bias, but we show that embryo size is unlikely to be a major factor in preservation. Under some conditions of death, fossilized remains will not accurately reflect the cell structure of the living organism. Although embryos within the fertilization envelope have high preservation potential, primary larvae have negligible preservation potential. Thus the paleo-embryological record may have strong biases on developmental stages preserved. Our data provide a predictive basis for interpreting the fossil record to unravel the evolution of ontogeny in the origin of metazoans.

  14. Ethical Challenges of Embryo Donation in Embryo Donors and Recipients

    OpenAIRE

    Taebi, Mahboubeh; Bahrami, Reyhane; Bagheri-Lankarani, Narges; Shahriari, Mohsen

    2018-01-01

    Background: Embryo donation, as one of the novel assisted reproductive technologies (ART), has remained a controversial issue. This is due to this methods' need for individuals from outside the family circle. Their presence can cause many ethical issues and complicate the designing and planning of the embryo donation process. The present study was conducted with the aim to assess the ethical challenges of embryo donation from the view point of embryo donors and recipients. Material and Method...

  15. Synthetic seed production from somatic embryos of Pinus radiata.

    Science.gov (United States)

    Aquea, Felipe; Poupin, María Josefina; Matus, José Tomás; Gebauer, Marlene; Medina, Consuelo; Arce-Johnson, Patricio

    2008-10-01

    Pinus radiata is one of the most important forestry species in the southern hemisphere. This work describes the regeneration of this plant via somatic embryogenesis from immature zygotic embryos. To improve this process, somatic embryogenic cell suspensions were established in liquid media for the generation of material for embryo maturation. Each developmental stage of these suspensions was characterized by microscopy and their growth phases quantified. An alginate-containing medium was used as an encapsulation method for the somatic embryos that were then germinated as artificial seeds in vitro. The protocols described in this work are both useful and reliable for industrial purposes.

  16. Experimental taphonomy shows the feasibility of fossil embryos

    OpenAIRE

    Raff, Elizabeth C.; Villinski, Jeffrey T.; Turner, F. Rudolf; Donoghue, Philip C. J.; Raff, Rudolf A.

    2006-01-01

    The recent discovery of apparent fossils of embryos contemporaneous with the earliest animal remains may provide vital insights into the metazoan radiation. However, although the putative fossil remains are similar to modern marine animal embryos or larvae, their simple geometric forms also resemble other organic and inorganic structures. The potential for fossilization of animals at such developmental stages and the taphonomic processes that might affect preservation before mineralization ha...

  17. High dose progesterone effects the growth of early chick embryo

    International Nuclear Information System (INIS)

    Iqbal, I.; Qamar, K.

    2014-01-01

    Objective: To find out the effect of high dose progesterone on the development of early chick embryo. Study Design: Lab based randomized controlled trial. Place and Duration of study: This study was carried out in Army Medical College and Post Graduate Institute of Poultry Sciences, Rawalpindi from June 2010 - December 2010. Material and Methods: Forty five specific pathogen free, fertile, eggs of Fyoumi species of chick were selected at zero hour of incubation. They were incubated at 37.5oC and 75% relative humidity for 26 hrs until the embryos reached stage 8 of the development. Then on stage 8 the eggs were divided into three groups consisting of 15 eggs per group. The first group (GI) was incubated without any operation. The second (G2) and third groups (G3) were injected with two and twenty times more than physiologic does of progesterone respectively. After 48 hours of incvbation, all embryos were examined for their development under light microscopy. Results: All the embryos of G1 and G2 showed normal development according to their stage of development, while 4 out of 11 embryos of G3 were under developed and their survival rate was also less. Conclusion: Exogenous progesterone at levels twenty times above its physiologic range effects the development of chick embryos. Further studies are needed to explain the mechanisms of this effect. (author)

  18. Climatic factors affecting quantity and quality grade of in vivo derived embryos of cattle.

    Science.gov (United States)

    Chinchilla-Vargas, Josué; Jahnke, Marianna M; Dohlman, Tyler M; Rothschild, Max F; Gunn, Patrick J

    2018-02-17

    The present study investigated the effects of climatic variables on the quality grade and quantity of in vivo derived cattle embryos in the Midwestern United States. Climatic information included greatest and least daily temperature, average daily wind speed and average temperature-humidity index for each of the 765 records. The response variables included the number of ovarian structures, viable embryos, quality grade 1 embryos, quality grade 2 embryos, quality grade 3 embryos, freezable embryos (sum of quality grade 1 and quality grade 2 embryos), transferable embryos (sum of quality grade 1-3 embryos), degenerate embryos and unfertilized ova. Measures for variables among the breeds of donors and sires grouped by geographical origin were compared. A negative effect of greater temperatures during the early embryonic development stage tended (P climatic variables have significant effects on the in vivo production of cattle embryos and that wind speed should be considered in future analyses of factors affecting embryo quality. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Effect of Medium Salt Concentration on Differentiation and Maturation of Somatic Embryos of Cassava (Manihot esculenta Crantz)

    OpenAIRE

    GROLL, J.; MYCOCK, D. J.; GRAY, V. M.

    2002-01-01

    Culture of cassava somatic embryos on media with an altered macro‐ and micro‐nutrient salt concentration affected embryo development and germination capability. In the tests, quarter‐, half‐, full‐ or double‐strength Murashige and Skoog (MS) media were compared. The maximum number of somatic embryos differentiated from a proliferative nodular embryogenic callus (NEC) on either half‐ or full‐strength MS medium, and the greatest numbers of cotyledonary stage embryos were formed on full‐strength...

  20. L- carnitine and trans-10, cis-12 conjugated linoleic acid on in vitro bovine embryo production and cryopreservation

    OpenAIRE

    Zolini, Adriana Moreira

    2015-01-01

    High lipid content in embryo is associated with low freezing tolerance. This study assessed the effects of exogenous L-carnitine and trans-10, cis-12 (t10, c12) conjugated linoleic acid (CLA) on in-vitro development and cryotolerance of bovine embryos when added during different stages of in vitro production of embryos. For all experiments, embryos were produced in vitro using slaughterhouse cows oocytes. Cleavage rates on Day 3, blastocyst and advanced blastocyst (hatching/hatched blastocyst...

  1. Radiation effects on cultured mouse embryos in relation to cell division cycle

    International Nuclear Information System (INIS)

    Domon, M.

    1982-01-01

    The authors have worked with mouse embryos in vitro asking first, what are the suitable parameters to define the radiation sensitivity of embryos, and second what is a major factor determining it. The LD 50 was adopted as a parameter of the radiation sensitivity of a population in a mouse embryo system in culture. The fertilized ova were collected into Whitten's medium at various times during the pronuclear and 2-cell stages of development. They were irradiated in chambers with X-rays at doses of 0 to 800 rads. After the embryos were cultured, a set of the lethal fractions for various X-ray doses were obtained. Regarding the radiation sensitivity variation of the embryos, the LD 50 varied from 100 to 200 rads during the pronuclear stage and from 100 to 600 rads during the 2-cell stage. The embryos during the pronuclear stage were most radioresistant at early G 2 phase, followed by an increase in the sensitivity. The embryos during the 2-cell stage were also most radioresistant at early G 2 phase and were more sensitive when they got close to either the first or the second cleavage division. Furthermore, it seems that the factor 6 of the large variation was due to the extremely long G 2 period, 14 hrs for the 2-cell embryos. That is, the pooled 2-cell embryos were in a relative sense well synchronized with G 2 phase. In contrast, the synchrony was poor during the pronuclear stage, which led to less variation of the LD 50 for the pronuclear embryos. It is concluded that during the early cleavage stages of mice, radiosensitivity is mainly governed by the content of cells of various cell cycle ages in the embryo. (Namekawa, K.)

  2. Ovarian stimulation and embryo quality

    NARCIS (Netherlands)

    Baart, Esther; Macklon, Nick S.; Fauser, Bart J. C. M.

    To Study the effects of different ovarian stimulation approaches on oocyte and embryo quality, it is imperative to assess embryo quality with a reliable and objective method. Embryos rated as high quality by standardized morphological assessment are associated with higher implantation and pregnancy

  3. Effects of 60Co gamma radiation on Biomphalaria glabrata (Say, 1818) Embryo, I. Mortality

    International Nuclear Information System (INIS)

    Okazaki, K.; Kawano, T.

    1990-01-01

    A study was conducted on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10,15,20 and 25 Gy of 60 Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality was the parameter used to evaluated the damage induced by ionizing radiation. Susceptibility decreased with increasing embryo age and with decreased radiation dose. Estimated LD 50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). The survival curves obtained for each embryo stage are discussed on the basis of the multitarget theory. (author) [pt

  4. impact on embryo quality

    Directory of Open Access Journals (Sweden)

    Marijan Tandara

    2013-05-01

    Conclusions: In men with poorer semen quality, evaluated by standard semen parameters, a higher proportion of sperm with damaged DNA can also be expected. Higher sperm DNA damage, established by Halosperm test, also had an impact on embryo quality in this group of patients.

  5. Embryo Aggregation in Pig Improves Cloning Efficiency and Embryo Quality.

    Science.gov (United States)

    Buemo, Carla Paola; Gambini, Andrés; Moro, Lucia Natalia; Hiriart, María Inés; Fernández-Martín, Rafael; Collas, Philippe; Salamone, Daniel Felipe

    2016-01-01

    In this study, we analyzed the effects of the cloned embryo aggregation on in vitro embryo development and embryo quality by measuring blastocyst diameter and cell number, DNA fragmentation levels and the expression of genes associated with pluripotency, apoptosis, trophoblast and DNA methylation in the porcine. Zona-free reconstructed cloned embryos were cultured in the well of the well system, placing one (1x non aggregated group) or three (3x group) embryos per microwell. Our results showed that aggregation of three embryos increased blastocyst formation rate and blastocyst diameter of cloned pig embryos. DNA fragmentation levels in 3x aggregated cloned blastocysts were significantly decreased compared to 1x blastocysts. Levels of Oct4, Klf4, Igf2, Bax and Dnmt 1 transcripts were significantly higher in aggregated embryos, whereas Nanog levels were not affected. Transcripts of Cdx2 and Bcl-xl were essentially non-detectable. Our study suggests that embryo aggregation in the porcine may be beneficial for cloned embryo development and embryo quality, through a reduction in apoptotic levels and an improvement in cell reprogramming.

  6. Early Cambrian pentamerous cubozoan embryos from South China.

    Directory of Open Access Journals (Sweden)

    Jian Han

    Full Text Available BACKGROUND: Extant cubozoans are voracious predators characterized by their square shape, four evenly spaced outstretched tentacles and well-developed eyes. A few cubozoan fossils are known from the Middle Cambrian Marjum Formation of Utah and the well-known Carboniferous Mazon Creek Formation of Illinois. Undisputed cubozoan fossils were previously unknown from the early Cambrian; by that time probably all representatives of the living marine phyla, especially those of basal animals, should have evolved. METHODS: Microscopic fossils were recovered from a phosphatic limestone in the Lower Cambrian Kuanchuanpu Formation of South China using traditional acetic-acid maceration. Seven of the pre-hatched pentamerous cubozoan embryos, each of which bears five pairs of subumbrellar tentacle buds, were analyzed in detail through computed microtomography (Micro-CT and scanning electron microscopy (SEM without coating. RESULTS: The figured microscopic fossils are unequivocal pre-hatching embryos based on their spherical fertilization envelope and the enclosed soft-tissue that has preserved key anatomical features arranged in perfect pentaradial symmetry, allowing detailed comparison with modern cnidarians, especially medusozoans. A combination of features, such as the claustrum, gonad-lamella, suspensorium and velarium suspended by the frenula, occur exclusively in the gastrovascular system of extant cubozoans, indicating a cubozoan affinity for these fossils. Additionally, the interior anatomy of these embryonic cubozoan fossils unprecedentedly exhibits the development of many new septum-derived lamellae and well-partitioned gastric pockets unknown in living cubozoans, implying that ancestral cubozoans had already evolved highly specialized structures displaying unexpected complexity at the dawn of the Cambrian. The well-developed endodermic lamellae and gastric pockets developed in the late embryonic stages of these cubozoan fossils are comparable with

  7. Early Cambrian pentamerous cubozoan embryos from South China.

    Science.gov (United States)

    Han, Jian; Kubota, Shin; Li, Guoxiang; Yao, Xiaoyong; Yang, Xiaoguang; Shu, Degan; Li, Yong; Kinoshita, Shunichi; Sasaki, Osamu; Komiya, Tsuyoshi; Yan, Gang

    2013-01-01

    Extant cubozoans are voracious predators characterized by their square shape, four evenly spaced outstretched tentacles and well-developed eyes. A few cubozoan fossils are known from the Middle Cambrian Marjum Formation of Utah and the well-known Carboniferous Mazon Creek Formation of Illinois. Undisputed cubozoan fossils were previously unknown from the early Cambrian; by that time probably all representatives of the living marine phyla, especially those of basal animals, should have evolved. Microscopic fossils were recovered from a phosphatic limestone in the Lower Cambrian Kuanchuanpu Formation of South China using traditional acetic-acid maceration. Seven of the pre-hatched pentamerous cubozoan embryos, each of which bears five pairs of subumbrellar tentacle buds, were analyzed in detail through computed microtomography (Micro-CT) and scanning electron microscopy (SEM) without coating. The figured microscopic fossils are unequivocal pre-hatching embryos based on their spherical fertilization envelope and the enclosed soft-tissue that has preserved key anatomical features arranged in perfect pentaradial symmetry, allowing detailed comparison with modern cnidarians, especially medusozoans. A combination of features, such as the claustrum, gonad-lamella, suspensorium and velarium suspended by the frenula, occur exclusively in the gastrovascular system of extant cubozoans, indicating a cubozoan affinity for these fossils. Additionally, the interior anatomy of these embryonic cubozoan fossils unprecedentedly exhibits the development of many new septum-derived lamellae and well-partitioned gastric pockets unknown in living cubozoans, implying that ancestral cubozoans had already evolved highly specialized structures displaying unexpected complexity at the dawn of the Cambrian. The well-developed endodermic lamellae and gastric pockets developed in the late embryonic stages of these cubozoan fossils are comparable with extant pelagic juvenile cubomedusae rather than

  8. From callus to embryo: a proteomic view on the development and maturation of somatic embryos in Cyclamen persicum.

    Science.gov (United States)

    Rode, Christina; Lindhorst, Kathrin; Braun, Hans-Peter; Winkelmann, Traud

    2012-05-01

    In this study, the proteome structures following the pathway in somatic embryogenesis of Cyclamen persicum were analysed via high-resolution 2D-SDS-PAGE with two objectives: (1) to identify the significant physiological processes during somatic embryogenesis in Cyclamen and (2) to improve the maturation of somatic embryos. Therefore, the effects of maturation-promoting plant growth regulator abscisic acid (ABA) and high sucrose levels on torpedo-shaped embryos were investigated. In total, 108 proteins of differential abundance were identified using a combination of tandem mass spectrometry and a digital proteome reference map. In callus, enzymes related to energy supply were especially distinct, most likely due to energy demand caused by fast growth and cell division. The switch from callus to globular embryo as well as from globular to torpedo-shaped embryo was associated with controlled proteolysis via the ubiquitin-26S proteasome pathway. Storage compound accumulation was first detected 21 days after transfer to plant growth regulator (PGR)-free medium in early torpedo-shaped embryos. Increase in abundance of auxin-amidohydrolase during embryogenesis suggests a possible increase in auxin release in the late embryo stages of Cyclamen. A development-specific isoelectric point switch of catalases has been reported for the first time for somatic embryogenesis. Several proteins were identified to represent markers for the different developmental stages analysed. High sucrose levels and ABA treatment promoted the accumulation of storage compounds in torpedo-shaped embryos. Additionally, proteins of the primary metabolic pathways were decreased in the proteomes of ABA-treated embryos. Thus, ABA and high sucrose concentration in the culture medium improved maturation and consequently the quality of somatic embryos in C. persicum.

  9. Halogenated flame retardants during egg formation and chicken embryo development: maternal transfer, possible biotransformation, and tissue distribution.

    Science.gov (United States)

    Zheng, Xiao-Bo; Luo, Xiao-Jun; Zeng, Yan-Hong; Wu, Jiang-Ping; Chen, She-Jun; Mai, Bi-Xian

    2014-08-01

    Hen muscle, eggs, and newborn chick tissues (muscle and liver) were collected from an electronic waste recycling site in southern China. The authors examined the maternal transfer, potential metabolism, and tissue distribution of several halogenated flame retardants (HFRs) during egg formation and chicken embryo development. The pollutant composition changes significantly from hen muscle to eggs and from eggs to tissues of newborn chicks. Higher-halogenated chemicals, such as octa- to deca-polybrominated diphenyl ether (PBDE) congeners, deca-polybrominated biphenyl (PBB209), and dechlorane plus (DP), are less readily transferred to eggs compared with lower-halogenated chemicals. During embryo development, PBDEs are the most likely to be metabolized, whereas decabromodiphenyl ethane (DBDPE) is the least. The authors also observed selective maternal transfer of anti-DP and stereoselective metabolism of syn-DP during chicken embryo development. During tissue development, liver has greater affinity than the muscle for chemcials with a high log octanol-water partition coefficient, with the exception of DBDPE. The differences in metabolism potential of different chemicals in chicken embryos cause pollutant composition alterations. Halogenated flame retardant from maternal transfer and tissue distribution also exhibited chemical specificity, especially for DBDPE. Levels of DBDPE were elevated along with the full process from hen muscle to eggs and from eggs to chick tissues. More attention should be paid to the selective accumulation and biotransformation of HFRs in the early development stage of birds. © 2014 SETAC.

  10. Beneficial effect of two culture systems with small groups of embryos on the development and quality of in vitro-produced bovine embryos.

    Science.gov (United States)

    Cebrian-Serrano, A; Salvador, I; Silvestre, M A

    2014-02-01

    Currently, in vitro-produced embryos derived by ovum pick up (OPU) and in vitro fertilization (IVF) technologies represent approximately one-third of the embryos worldwide in cattle. Nevertheless, the culture of small groups of embryos from an individual egg donor is an issue that OPU-IVF laboratories have to face. In this work, we tested whether the development and quality of the preimplantation embryos in vitro cultured in low numbers (five embryos) could be improved by the addition of epidermal growth factor, insulin, transferrin and selenium (EGF-ITS) or by the WOW system. With this aim, immature oocytes recovered from slaughtered heifers were in vitro matured and in vitro fertilized. Presumptive zygotes were then randomly cultured in four culture conditions: one large group (LG) (50 embryos/500 μl medium) and three smaller groups [five embryos/50 μl medium without (control) or with EGF-ITS (EGF-ITS) and five embryos per microwell in the WOW system (WOW)]. Embryos cultured in LG showed a greater ability to develop to blastocyst stage than embryos cultured in smaller groups, while the blastocyst rate of WOW group was significantly higher than in control. The number of cells/blastocyst in LG was higher than control or WOW, whereas the apoptosis rate per blastocyst was lower. On the other hand, the addition of EGF-ITS significantly improved both parameters compared to the control and resulted in similar embryo quality to LG. In conclusion, the WOW system improved embryo development, while the addition of EGF-ITS improved the embryo quality when smaller groups of embryos were cultured. © 2013 Blackwell Verlag GmbH.

  11. HSPC117 deficiency in cloned embryos causes placental abnormality and fetal death

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yingying [Department of Reproduction and Development, Kunming Institute of Zoology and Kunming Primate Research Center, Chinese Academy of Sciences, Kunming 650223 (China); State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Hai, Tang; Liu, Zichuan; Zhou, Shuya; Lv, Zhuo [State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Ding, Chenhui; Liu, Lei [State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China); Niu, Yuyu [Department of Reproduction and Development, Kunming Institute of Zoology and Kunming Primate Research Center, Chinese Academy of Sciences, Kunming 650223 (China); Zhao, Xiaoyang; Tong, Man [State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, Liu [State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China); Jouneau, Alice [INRA, UMR 1198, ENVA, CNRS, FRE 2857, Biologie du Developpement et Reproduction, Jouy en Josas F-78350 (France); Zhang, Xun [Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114 (United States); Ji, Weizhi, E-mail: wji@mail.kiz.ac.cn [Department of Reproduction and Development, Kunming Institute of Zoology and Kunming Primate Research Center, Chinese Academy of Sciences, Kunming 650223 (China); Zhou, Qi, E-mail: qzhou@ioz.ac.cn [State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080 (China)

    2010-07-02

    Somatic cell nuclear transfer (SCNT) has been successfully used in many species to produce live cloned offspring, albeit with low efficiency. The low frequency of successful development has usually been ascribed to incomplete or inappropriate reprogramming of the transferred nuclear genome. Elucidating the genetic differences between normal fertilized and cloned embryos is key to understand the low efficiency of SCNT. Here, we show that expression of HSPC117, which encodes a hypothetical protein of unknown function, was absent or very low in cloned mouse blastocysts. To investigate the role of HSPC117 in embryo development, we knocked-down this gene in normal fertilized embryos using RNA interference. We assessed the post-implantation survival of HSPC117 knock-down embryos at 3 stages: E9 (prior to placenta formation); E12 (after the placenta was fully functional) and E19 (post-natal). Our results show that, although siRNA-treated in vivo fertilized/produced (IVP) embryos could develop to the blastocyst stage and implanted without any difference from control embryos, the knock-down embryos showed substantial fetal death, accompanied by placental blood clotting, at E12. Furthermore, comparison of HSPC117 expression in placentas of nuclear transfer (NT), intracytoplasmic sperm injection (ICSI) and IVP embryos confirmed that HSPC117 deficiency correlates well with failures in embryo development: all NT embryos with a fetus, as well as IVP and ICSI embryos, had normal placental HSPC117 expression while those NT embryos showing reduced or no expression of HSPC117 failed to form a fetus. In conclusion, we show that HSPC117 is an important gene for post-implantation development of embryos, and that HSPC117 deficiency leads to fetal abnormalities after implantation, especially following placental formation. We suggest that defects in HSPC117 expression may be an important contributing factor to loss of cloned NT embryos in vivo.

  12. HSPC117 deficiency in cloned embryos causes placental abnormality and fetal death

    International Nuclear Information System (INIS)

    Wang, Yingying; Hai, Tang; Liu, Zichuan; Zhou, Shuya; Lv, Zhuo; Ding, Chenhui; Liu, Lei; Niu, Yuyu; Zhao, Xiaoyang; Tong, Man; Wang, Liu; Jouneau, Alice; Zhang, Xun; Ji, Weizhi; Zhou, Qi

    2010-01-01

    Somatic cell nuclear transfer (SCNT) has been successfully used in many species to produce live cloned offspring, albeit with low efficiency. The low frequency of successful development has usually been ascribed to incomplete or inappropriate reprogramming of the transferred nuclear genome. Elucidating the genetic differences between normal fertilized and cloned embryos is key to understand the low efficiency of SCNT. Here, we show that expression of HSPC117, which encodes a hypothetical protein of unknown function, was absent or very low in cloned mouse blastocysts. To investigate the role of HSPC117 in embryo development, we knocked-down this gene in normal fertilized embryos using RNA interference. We assessed the post-implantation survival of HSPC117 knock-down embryos at 3 stages: E9 (prior to placenta formation); E12 (after the placenta was fully functional) and E19 (post-natal). Our results show that, although siRNA-treated in vivo fertilized/produced (IVP) embryos could develop to the blastocyst stage and implanted without any difference from control embryos, the knock-down embryos showed substantial fetal death, accompanied by placental blood clotting, at E12. Furthermore, comparison of HSPC117 expression in placentas of nuclear transfer (NT), intracytoplasmic sperm injection (ICSI) and IVP embryos confirmed that HSPC117 deficiency correlates well with failures in embryo development: all NT embryos with a fetus, as well as IVP and ICSI embryos, had normal placental HSPC117 expression while those NT embryos showing reduced or no expression of HSPC117 failed to form a fetus. In conclusion, we show that HSPC117 is an important gene for post-implantation development of embryos, and that HSPC117 deficiency leads to fetal abnormalities after implantation, especially following placental formation. We suggest that defects in HSPC117 expression may be an important contributing factor to loss of cloned NT embryos in vivo.

  13. Radial extracorporeal shock wave treatment harms developing chicken embryos

    Science.gov (United States)

    Kiessling, Maren C.; Milz, Stefan; Frank, Hans-Georg; Korbel, Rüdiger; Schmitz, Christoph

    2015-01-01

    Radial extracorporeal shock wave treatment (rESWT) has became one of the best investigated treatment modalities for cellulite, including the abdomen as a treatment site. Notably, pregnancy is considered a contraindication for rESWT, and concerns have been raised about possible harm to the embryo when a woman treated with rESWT for cellulite is not aware of her pregnancy. Here we tested the hypothesis that rESWT may cause serious physical harm to embryos. To this end, chicken embryos were exposed in ovo to various doses of radial shock waves on either day 3 or day 4 of development, resembling the developmental stage of four- to six-week-old human embryos. We found a dose-dependent increase in the number of embryos that died after radial shock wave exposure on either day 3 or day 4 of development. Among the embryos that survived the shock wave exposure a few showed severe congenital defects such as missing eyes. Evidently, our data cannot directly be used to draw conclusions about potential harm to the embryo of a pregnant woman treated for cellulite with rESWT. However, to avoid any risks we strongly recommend applying radial shock waves in the treatment of cellulite only if a pregnancy is ruled out. PMID:25655309

  14. Radial extracorporeal shock wave treatment harms developing chicken embryos.

    Science.gov (United States)

    Kiessling, Maren C; Milz, Stefan; Frank, Hans-Georg; Korbel, Rüdiger; Schmitz, Christoph

    2015-02-06

    Radial extracorporeal shock wave treatment (rESWT) has became one of the best investigated treatment modalities for cellulite, including the abdomen as a treatment site. Notably, pregnancy is considered a contraindication for rESWT, and concerns have been raised about possible harm to the embryo when a woman treated with rESWT for cellulite is not aware of her pregnancy. Here we tested the hypothesis that rESWT may cause serious physical harm to embryos. To this end, chicken embryos were exposed in ovo to various doses of radial shock waves on either day 3 or day 4 of development, resembling the developmental stage of four- to six-week-old human embryos. We found a dose-dependent increase in the number of embryos that died after radial shock wave exposure on either day 3 or day 4 of development. Among the embryos that survived the shock wave exposure a few showed severe congenital defects such as missing eyes. Evidently, our data cannot directly be used to draw conclusions about potential harm to the embryo of a pregnant woman treated for cellulite with rESWT. However, to avoid any risks we strongly recommend applying radial shock waves in the treatment of cellulite only if a pregnancy is ruled out.

  15. Embryo wastage rates remain high in assisted reproductive technology (ART): a look at the trends from 2004-2013 in the USA.

    Science.gov (United States)

    Ghazal, Sanaz; Patrizio, Pasquale

    2017-02-01

    This work examined the trend in "embryo wastage" rates after ART in USA and its relationship to the number of embryos transferred, live born infants delivered across patient age, and the yearly percentage of embryos wasted. The data were obtained from the US-clinics SART databank for the years 2004-2013. A total of 1,808,082 non-donor embryos were transferred in 748,394 fresh cycles resulting in 358,214 liveborn. During the years of analysis, the mean number of embryos transferred has progressively decreased leading to an overall significant decrease in Embryo Wastage rates (83.2 to 76.5%, p ART cycle are competent. The overall "Embryo Wastage" rates have consistently decreased from a high of 90% in 1995 to a rate of 76.5% in 2013. Transferring fewer embryos particularly at the blastocyst-stage and improved methods of embryo selection may further decrease "Embryo Wastage" rates.

  16. The sensitivity of grass shrimp, Palaemonetes pugio, embryos to organophosphate pesticide induced acetylcholinesterase inhibition.

    Science.gov (United States)

    Lund; Fulton; Key

    2000-03-01

    Grass shrimp, Palaemonetes pugio, are common inhabitants of salt marshes along the Atlantic and Gulf coasts of North America. Grass shrimp embryos are brooded externally on the abdomen of adult females for about 2 weeks prior to hatching. In South Carolina, the spring spawning period for grass shrimp coincides with the period of peak pesticide application on crops grown along the South Carolina coast. Thus, grass shrimp of all developmental stages are at risk of exposure to pesticides present in nonpoint source agricultural runoff. Organophosphate (OP) insecticides are commonly applied agricultural chemicals which produce toxicity by inhibiting the nervous system enzyme, acetylcholinesterase (AChE). The purpose of this study was to examine the development of AChE activity in grass shrimp embryos and to assess their sensitivity to OP-induced AChE inhibition. Embryos were exposed for 24 h to either chlorpyrifos or malathion. All exposure concentrations were nominal and ranged from 0 to 2.00 µg l(-1) for chlorpyrifos and from 0 to 120.00 µg l(-1) for malathion. Quantifiable levels of AChE activity first appeared at Stage V of development and increased as embryonic development progressed. AChE inhibition by the OPs was assessed in Stage VI and Stage VII embryos. Both stages of embryos were more sensitive to chlorpyrifos than malathion. The 24-h Effective Concentration (EC(50)) values for chlorpyrifos were 0.49 µg l(-1) (95% C.I.=0.33-0.77 µg l(-1)) and 0.36 µg l(-1) (95% C.I.=0.33-0.38 µg l(-1)) for Stage VI and Stage VII embryos, respectively. In comparison, malathion 24-h EC(50) values were 55.53 µg l(-1) (95% C.I.=22.08-80.73 µg l(-1)) for Stage VI embryos and 29.93 µg l(-1) (95% C.I.=25.22-44.22 µg l(-1)) for Stage VII embryos. For both OPs, there were no significant differences in the EC(50) values calculated for Stage VI and Stage VII embryos; however, AChE inhibition was significantly (Pinsecticide. A comparison of the results of these embryo tests

  17. The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis.

    Science.gov (United States)

    Cimadomo, Danilo; Capalbo, Antonio; Ubaldi, Filippo Maria; Scarica, Catello; Palagiano, Antonio; Canipari, Rita; Rienzi, Laura

    2016-01-01

    Preimplantation Genetic Diagnosis and Screening (PGD/PGS) for monogenic diseases and/or numerical/structural chromosomal abnormalities is a tool for embryo testing aimed at identifying nonaffected and/or euploid embryos in a cohort produced during an IVF cycle. A critical aspect of this technology is the potential detrimental effect that the biopsy itself can have upon the embryo. Different embryo biopsy strategies have been proposed. Cleavage stage blastomere biopsy still represents the most commonly used method in Europe nowadays, although this approach has been shown to have a negative impact on embryo viability and implantation potential. Polar body biopsy has been proposed as an alternative to embryo biopsy especially for aneuploidy testing. However, to date no sufficiently powered study has clarified the impact of this procedure on embryo reproductive competence. Blastocyst stage biopsy represents nowadays the safest approach not to impact embryo implantation potential. For this reason, as well as for the evidences of a higher consistency of the molecular analysis when performed on trophectoderm cells, blastocyst biopsy implementation is gradually increasing worldwide. The aim of this review is to present the evidences published to date on the impact of the biopsy at different stages of preimplantation development upon human embryos reproductive potential.

  18. The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis

    Directory of Open Access Journals (Sweden)

    Danilo Cimadomo

    2016-01-01

    Full Text Available Preimplantation Genetic Diagnosis and Screening (PGD/PGS for monogenic diseases and/or numerical/structural chromosomal abnormalities is a tool for embryo testing aimed at identifying nonaffected and/or euploid embryos in a cohort produced during an IVF cycle. A critical aspect of this technology is the potential detrimental effect that the biopsy itself can have upon the embryo. Different embryo biopsy strategies have been proposed. Cleavage stage blastomere biopsy still represents the most commonly used method in Europe nowadays, although this approach has been shown to have a negative impact on embryo viability and implantation potential. Polar body biopsy has been proposed as an alternative to embryo biopsy especially for aneuploidy testing. However, to date no sufficiently powered study has clarified the impact of this procedure on embryo reproductive competence. Blastocyst stage biopsy represents nowadays the safest approach not to impact embryo implantation potential. For this reason, as well as for the evidences of a higher consistency of the molecular analysis when performed on trophectoderm cells, blastocyst biopsy implementation is gradually increasing worldwide. The aim of this review is to present the evidences published to date on the impact of the biopsy at different stages of preimplantation development upon human embryos reproductive potential.

  19. Seed architecture shapes embryo metabolism in oilseed rape.

    Science.gov (United States)

    Borisjuk, Ljudmilla; Neuberger, Thomas; Schwender, Jörg; Heinzel, Nicolas; Sunderhaus, Stephanie; Fuchs, Johannes; Hay, Jordan O; Tschiersch, Henning; Braun, Hans-Peter; Denolf, Peter; Lambert, Bart; Jakob, Peter M; Rolletschek, Hardy

    2013-05-01

    Constrained to develop within the seed, the plant embryo must adapt its shape and size to fit the space available. Here, we demonstrate how this adjustment shapes metabolism of photosynthetic embryo. Noninvasive NMR-based imaging of the developing oilseed rape (Brassica napus) seed illustrates that, following embryo bending, gradients in lipid concentration became established. These were correlated with the local photosynthetic electron transport rate and the accumulation of storage products. Experimentally induced changes in embryo morphology and/or light supply altered these gradients and were accompanied by alterations in both proteome and metabolome. Tissue-specific metabolic models predicted that the outer cotyledon and hypocotyl/radicle generate the bulk of plastidic reductant/ATP via photosynthesis, while the inner cotyledon, being enclosed by the outer cotyledon, is forced to grow essentially heterotrophically. Under field-relevant high-light conditions, major contribution of the ribulose-1,5-bisphosphate carboxylase/oxygenase-bypass to seed storage metabolism is predicted for the outer cotyledon and the hypocotyl/radicle only. Differences between in vitro- versus in planta-grown embryos suggest that metabolic heterogeneity of embryo is not observable by in vitro approaches. We conclude that in vivo metabolic fluxes are locally regulated and connected to seed architecture, driving the embryo toward an efficient use of available light and space.

  20. Cells, embryos and development in space

    Science.gov (United States)

    Krikorian, A. D.

    1984-01-01

    Work continues to focus on the demonstrable totipotency of cultured somatic cells of various higher plants and has examined the conditions which regulate this propensity to be controllably released. This was done with special reference to cells obtained from cultured explants of daylily and carrot. For purposes of identifying the variables in question, work was carried out almost exclusively in liquid media. The events that intervene between the aseptic isolation of tissue explants, the culture of small derived units and free cells and the propagation in large numbers of adventive or somatic embryos to plantlets were traced and certain definitive stages at which control is exercised were identified. In daylily, morphologically competent units are now propagated with a high degree of precision in rotated liquid cultures in bulk, and under the conditions of continuous neutralized gravity, the development progresses so that embryo-plantlets are obtained.

  1. Action of uranium on pre implanted mouse embryos

    International Nuclear Information System (INIS)

    Kundt, Miriam S.

    2001-01-01

    The cultured preimplantation embryos are normally employed to evaluate the effects of environmental pollutants specially metals. Embryos were obtained from hybrid females CBA x C57 Bl following induction of super ovulation. They were incubated from 1 cell stage during 120 hs. in M16 cultured medium. Three different experiments were carried out: A, B and C using uranyl nitrate UO 2 (NO 3 ) 2 6H 2 O as source of uranium. In experiment 'A' the embryos were cultivated in the same culture dish containing final U concentrations of 13, 26, 52, 104 and 208 μgU/ml. In experiment 'B' embryos in a one cell stage were placed in culture medium with uranyl nitrate with final U concentrations of 26, 52, 104 μgU/ml. After 24 hours those embryos which had reached the two-cell stage were transferred to another culture dish to which fresh solutions of uranyl nitrate were added, maintaining the same concentrations of the previous one. In experiment 'C' the embryos were cultivated containing final U concentrations of 26, 52 and 104 μgU/ml and they were transferred to another culture dish every day to which fresh solutions of uranyl nitrate were added. Different embryos parameters were analyzed: 1) Development grade; 2) Number of cell per embryo and metaphases index; and 3) Embryo ploidy. 1) Embryos were observed each 24 hs. to evaluate development grade: 2, 4 and 8 cell stage, morula, early -expanded- hatched blastocysts and atresic embryos. No significant differences were observed in the proportion of embryos arrested either in the one-cell or in the two cell stages in control culture medium regarding different concentrations of U, in a total of 4388 embryos analyzed. From 2 cell stage, moment that the embryo begins to synthesize its own ARNm, the delay in embryonic development increased dose dependent. On the other hand, the toxicological effects in the same concentration are increase from 'A' treatment to 'C' treatment. Embriotoxicology effects are evidenced by an increment in

  2. Poor Prognosis with In Vitro Fertilization in Indian Women Compared to Caucasian Women Despite Similar Embryo Quality

    OpenAIRE

    Shahine, Lora K.; Lamb, Julie D.; Lathi, Ruth B.; Milki, Amin A.; Langen, Elizabeth; Westphal, Lynn M.

    2009-01-01

    BACKGROUND: Disease prevalence and response to medical therapy may differ among patients of diverse ethnicities. Poor outcomes with in vitro fertilization (IVF) treatment have been previously shown in Indian women compared to Caucasian women, and some evidence suggests that poor embryo quality may be a cause for the discrepancy. In our center, only patients with the highest quality cleavage stage embryos are considered eligible for extending embryo culture to the blastocyst stage. We compared...

  3. Silver nanoparticles incite size- and dose-dependent developmental phenotypes and nanotoxicity in zebrafish embryos.

    Science.gov (United States)

    Browning, Lauren M; Lee, Kerry J; Nallathamby, Prakash D; Xu, Xiao-Hong Nancy

    2013-10-21

    Nanomaterials possess distinctive physicochemical properties and promise a wide range of applications, from advanced technology to leading-edge medicine. However, their effects on living organisms remain largely unknown. Here we report that the purified silver nanoparticles (Ag NPs) (97 ± 13 nm) incite specific developmental stage embryonic phenotypes and nanotoxicity in a dose-dependent manner, upon acute exposure of given stage embryos to the NPs (0-24 pM) for only 2 h. The critical concentrations of the NPs that cause 50% of embryos to develop normally for cleavage, early gastrula, early segmentation, late segmentation, and hatching stage zebrafish embryos are 3.5, 4, 6, 6, and 8 pM, respectively, showing that the earlier developmental stage embryos are much more sensitive to the effects of the NPs than the later stage embryos. Interestingly, distinctive phenotypes (head abnormality and no eyes) are observed only in cleavage and early gastrula stage embryos treated with the NPs, showing the stage-specific effects of the NPs. By comparing these Ag NPs with smaller Ag NPs (13.1 ± 2.5 nm), we found that the embryonic phenotypes strikingly depend upon the sizes of Ag NPs and embryonic developmental stages. These notable findings suggest that the Ag NPs are unlike any conventional chemicals or ions. They can potentially enable target-specific study and therapy for early embryonic development in size-, stage-, dose-, and exposure duration-dependent manners.

  4. In vitro regeneration and morphogenesis of somatic embryos of cassava

    Directory of Open Access Journals (Sweden)

    Ádila Melo Vidal

    Full Text Available In this study, the somatic embryogenesis and regeneration of Cigana Preta plants from shoot apices and immature leaves taken from plants cultivated in vitro were examined. To embryo induction the explants were cultivated in Murashige and Skoog (MS medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D or 4-amino-3,5,6-trichloropicolinic acid (Picloram at concentrations of 8.0 and 12 mg L-1. To development of embryos two media cultures with different concentration of BAP (D1 or D2 were evaluated. Embryos in the cotyledonary stage were incubated in germination medium containing MS salts and vitamins, 2.0 µM copper sulfate, 2.4 g L-1 of Phytagel® and 1.77 µM BAP. The highest frequency of calluses and the greatest number of embryos per explant were obtained using the auxin picloram at a concentration of 8.0 mg L-1. The plants regenerated in the picloram treatment exhibited normal development and were transferred to a multiplication medium after a minimum of four weeks. The histological sections of the malformed embryos from foliar explants cultured in the presence of 2,4-D demonstrated that the origin of the cotyledonary structures was independent of the formation of the shoot apical meristem, which was not formed in the embryos, and the majority of the embryos were classified as cornet-shaped. This study demonstrates that in cassava, the use of different auxins provides different conditions for the formation of somatic embryos, and the low rate of conversion into plants results from abnormalities in the embryos.

  5. Effects of Co60 gamma radiation on Biomphalaria glabrata (Say, 1818) Embryo. II. Malformations

    International Nuclear Information System (INIS)

    Okazaki, K.; Kawano, T.

    1990-01-01

    The morphogenetic effects of ionizing radiation were investigated in Biomphalaria glabrata embryos irradiated in the cleavage, blastula, gastrula, young trochophore and trochophore stages with 5 to 25 Gy doses of 60 CO gamma radiation. The number of malformed embryos rapidly increased with increasing radiation dose, reaching a maximum between 5th to 8th day after irradiation in all stages analyzed. Susceptibility to malformation induction was higher the younger than the age of the irradiated embryo. However, for the cleavage stage the frequency of malformed embryos was inversely proportional to radiation dose for the same radiation dose. Several types of morphogenetic malformations were obtained, among then cephalic malformations, exogastrula, shell malformations and embryos with everted stomodeum, unspecific malformations being the most frequent. The results show that the types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied [pt

  6. Fusion of blastomeres in mouse embryos under the action of femtosecond laser radiation. Efficiency of blastocyst formation and embryo development

    Energy Technology Data Exchange (ETDEWEB)

    Osychenko, A A; Zalesskii, A D; Krivokharchenko, A S; Zhakhbazyan, A K; Nadtochenko, V A [N N Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow (Russian Federation); Ryabova, A V [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-05-31

    Using the method of femtosecond laser surgery we study the fusion of two-cell mouse embryos under the action of tightly focused femtosecond laser radiation with the fusion efficiency reaching 60%. The detailed statistical analysis of the efficiency of blastomere fusion and development of the embryo up to the blastocyst stage after exposure of the embryos from different mice to a femtosecond pulse is presented. It is shown that the efficiency of blastocyst formation essentially depends on the biological characteristics of the embryo, namely, the strain and age of the donor mouse. The possibility of obtaining hexaploid embryonal cells using the methods of femtosecond laser surgery is demonstrated. (extreme light fields and their applications)

  7. Developmental toxicity of cartap on zebrafish embryos.

    Science.gov (United States)

    Zhou, Shengli; Dong, Qiaoxiang; Li, Shaonan; Guo, Jiangfeng; Wang, Xingxing; Zhu, Guonian

    2009-12-13

    Cartap is a widely used insecticide which belongs to a member of nereistoxin derivatives and acts on nicotinic acetylcholine receptor site. Its effects on aquatic species are of grave concern. To explore the potential developmental toxicity of cartap, zebrafish embryos were continually exposed, from 0.5 to 144h post-fertilization, to a range of concentrations of 25-1000microg/l. Results of the experiment indicated that cartap concentrations of 100microg/l and above negatively affected embryo survival and hatching success. Morphological analysis uncovered a large suite of abnormalities such as less melanin pigmentation, wavy notochord, crooked trunk, fuzzy somites, neurogenesis defects and vasculature defects. The most sensitive organ was proved to be the notochord which displayed defects at concentrations as low as 25microg/l. Both sensitivity towards exposure and localization of the defect were stage specific. To elucidate mechanisms concerning notochord, pigmentation, and hatching defects, enzyme assay, RT Q-PCR, and different exposure strategies were performed. For embryos with hatching failure, chorion was verified not to be digested, while removing cartap from exposure at early pre-hatching stage could significantly increase the hatching success. However, cartap was proved, via vitro assay, to have no effect on proteolytic activity of hatching enzyme. These findings implied that the secretion of hatching enzyme might be blocked. We also revealed that cartap inhibited the activity of melanogenic enzyme tyrosinase and matrix enzyme lysyl oxidase and induced expression of their genes. These suggested that cartap could impaired melanin pigmentation of zebrafish embryos through inhibiting tyrosinase activity, while inhibition of lysyl oxidase activity was responsible for notochord undulation, which subsequently caused somite defect, and at least partially responsible for defects in vasculature and neurogenesis.

  8. Ethical Challenges of Embryo Donation in Embryo Donors and Recipients.

    Science.gov (United States)

    Taebi, Mahboubeh; Bahrami, Reyhane; Bagheri-Lankarani, Narges; Shahriari, Mohsen

    2018-01-01

    Embryo donation, as one of the novel assisted reproductive technologies (ART), has remained a controversial issue. This is due to this methods' need for individuals from outside the family circle. Their presence can cause many ethical issues and complicate the designing and planning of the embryo donation process. The present study was conducted with the aim to assess the ethical challenges of embryo donation from the view point of embryo donors and recipients. This descriptive, cross-sectional study was conducted on 192 couples (96 embryo donators and 96 embryo recipients) referring to Isfahan Fertility and Infertility Center and Royan Institute, Iran. The subjects were selected through convenience sampling. The data collection tool was the researcher-made Ethical Challenges Questionnaire. Data were analyzed in SPSS software. Embryo donors and recipients expresses the most important ethical challenges of embryo donation in the principle of justice (70.20%) and respect for autonomy (42.57%), respectively. The four ethical principles are important in the view of embryo donors and recipients; however, they highlighted the importance of the principle of respect for autonomy considering the existing barriers in the services of infertility centers. Legislators and relevant authorities must take measures toward the development of guidelines for this treatment method in the framework of ethics principles and incorporate all four principles independently.

  9. Ethical challenges of embryo donation in embryo donors and recipients

    Directory of Open Access Journals (Sweden)

    Mahboubeh Taebi

    2018-01-01

    Full Text Available Background: Embryo donation, as one of the novel assisted reproductive technologies (ART, has remained a controversial issue. This is due to this methods' need for individuals from outside the family circle. Their presence can cause many ethical issues and complicate the designing and planning of the embryo donation process. The present study was conducted with the aim to assess the ethical challenges of embryo donation from the view point of embryo donors and recipients. Material and Methods: This descriptive, cross-sectional study was conducted on 192 couples (96 embryo donators and 96 embryo recipients referring to Isfahan Fertility and Infertility Center and Royan Institute, Iran. The subjects were selected through convenience sampling. The data collection tool was the researcher-made Ethical Challenges Questionnaire. Data were analyzed in SPSS software. Results: Embryo donors and recipients expresses the most important ethical challenges of embryo donation in the principle of justice (70.20% and respect for autonomy (42.57%, respectively. Conclusions: The four ethical principles are important in the view of embryo donors and recipients; however, they highlighted the importance of the principle of respect for autonomy considering the existing barriers in the services of infertility centers. Legislators and relevant authorities must take measures toward the development of guidelines for this treatment method in the framework of ethics principles and incorporate all four principles independently.

  10. In vitro development of OPU-derived bovine embryos cultured either individually or in groups with the silk protein sericin and the viability of frozen-thawed embryos after transfer.

    Science.gov (United States)

    Isobe, Tomohiro; Ikebata, Yoshihisa; Do, Lanh Thi Kim; Tanihara, Fuminori; Taniguchi, Masayasu; Otoi, Takeshige

    2015-07-01

    The optimization of single-embryo culture conditions is very important, particularly in the in vitro production of bovine embryos using the ovum pick-up (OPU) procedure. The purpose of this study was to examine the development of embryos derived from oocytes obtained by OPU that were cultured either individually or in groups in medium supplemented with or without sericin and to investigate the viability of the frozen-thawed embryos after a direct transfer. When two-cell-stage embryos were cultured either individually or in groups for 7 days in CR1aa medium supplemented with or without 0.5% sericin, the rates of development to blastocysts and freezable blastocysts were significantly lower for the embryos cultured individually without sericin than for the embryos cultured in groups with or without sericin. Moreover, the rate of development to freezable blastocysts of the embryos cultured individually with sericin was significantly higher than that of the embryos cultured without sericin. When the frozen-thawed embryos were transferred directly to recipients, the rates of pregnancy, abortion, stillbirth and normal calving in the recipients were similar among the groups, irrespective of the culture conditions and sericin supplementation. Our findings indicate that supplementation with sericin during embryo culture improves the quality of the embryos cultured individually but not the viability of the frozen-thawed embryos after transfer to recipients. © 2014 Japanese Society of Animal Science.

  11. Proteomic analysis of embryo development in rice (Oryza sativa).

    Science.gov (United States)

    Xu, Hong; Zhang, Weiping; Gao, Yi; Zhao, Yong; Guo, Lin; Wang, Jianbo

    2012-04-01

    Although embryo development is a major subject in plant growth and development research, a number of aspects of the mechanism of this development process remain unknown. Rice (Oryza sativa) is an excellent monocot plant model for studying embryogenesis with a known genome sequence. Here, we conducted proteomic analysis of embryo development in rice (O. sativa L. ssp. indica cv. 9311). The aim was to investigate and characterize the changes in the protein expression profile during embryo development. For this purpose, the proteome of developing embryos was characterized by two-dimensional gel electrophoresis and nano liquid chromatography/mass spectrometry/mass spectrometry. Proteomic analyses identified 275 differentially expressed proteins throughout the 5 sequential developmental stages from 5 to 30 days after pollination. Most of these proteins were classified into eight functional categories: metabolism, protein synthesis/destination, disease and defense, transporter, transcription, signal transduction, cell growth/division, and storage proteins, which were involved in different cellular and metabolic processes. Hierarchical clustering analyses of protein expression profiles showed that highly expressed proteins in early stages were involved in metabolism, protein synthesis/destination, and most of the other cellular functions, whereas the proteins highly expressed in later stages functioned in the desiccation and dormancy of the embryo.

  12. Development of sheep androgenetic embryos is boosted following transfer of male pronuclei into androgenetic hemizygotes.

    Science.gov (United States)

    Matsukawa, Kazutsugu; Turco, Margherita Yayoi; Scapolo, Pier Augusto; Reynolds, Lawrence; Ptak, Grazyna; Loi, Pasqualino

    2007-01-01

    Androgenetic embryos are useful model for investigating the contribution of the paternal genome to embryonic development. Little work has been done with androgenetic embryo production in domestic animals. The aim of this study was the production of diploid androgenetic sheep embryos. In vitro matured sheep oocytes were enucleated and fertilized in vitro; parthenogenetic and normally fertilized embryos were also produced as a control. Fifteen hours after in vitro fertilization (IVF), presumptive zygotes were centrifuged and scored for the number of pronucleus. IVF, parthenogenetic, and androgenetic embryos (haploid, diploid, and triploid) were cultured in SOFaa medium with bovine serum albumin (BSA). The proportion of oocytes with polyspermic fertilization increased linearly with increasing sperm concentration. After IVF, there was no significant difference in early cleavage and morula formation rates between the groups, while there was a significant difference on blastocyst development between IVF, parthenogenetic, and androgenetic embryos, the last ones displaying poor developmental potential (IVF, parthenogenetic, and haploid, diploid, and triploid androgenetic embryos: 43%, 38%, 0%, 2%, and 2%, respectively). In order to boost androgenetic embryonic development, we produced diploid androgenetic embryos through pronuclear transfer. Single pronuclei were aspirated with a bevelled pipette from haploid or diploid embryos and transferred into the perivitelline space of other haploid embryos, and the zygotes were reconstructed by electrofusion. Fusion rates approached 100%. Pronuclear transfer significantly increased blastocyst development (IVF, parthenogenetic, androgenetic: Diploid into Haploid, and Haploid into Haploid: 42%, 42%, 19%, and 3%, respectively); intriguingly, the Haploid + Diploid group showed the highest development to blastocyst stage. The main findings of our study are: (1) sheep androgenetic embryos display poor developmental ability compared with

  13. DEVELOPMENT OF MICE AND HAMSTER EMBRYOS IN KSOMAA AND HECM-6 MEDIUM

    Directory of Open Access Journals (Sweden)

    Bayu Rosadi

    2008-12-01

    Full Text Available The purpose of the present study was to investigate the viability of mice and hamster embryos developed in Kalium Simplex Optimized Medium amino acid (KSOMaa and Hamster Embryo Culture Medium-6 (HECM-6 medium. Female DDY mice were superovulated by injection i.p. of 5 IU Pregnant Mare Serum Gonadotropine (PMSG and 5 IU Human Chorionic Gonadotropine (hCG in 48 h interval, hamster (Phodopus campbelli injected by 2.5 IU PMSG and 2.5 IU hCG 48 h later. Then females were mated with fertile males. Eight-cell embryos were recovered at day 3 after natural mating. The mice embryos were cultured in KSOMaa+5% NBCS (New Born Calf Serum (T1 and HECM-6+5% NBCS (T2, the hamster embryos were cultured in KSOMaa+5% NBCS (T3 and HECM-6 + 5% NBCS (T4 for further development at 37oC in a humidified atmosphere of 5% CO2 in air for 48 h. The examinations were replicated five times. The T1 embryos developed to compact morulla and early blastocyst 100% (140/140, 92.1% (129/140 to blastocyst and expanded blastocyst, and 22.9% (32/140 became hatching/hatched. The T3 reached 100% (60/60 to compact morulla and early blastocyst, 85.0% (51/60 blastocyst, and 48.3% (29/60 expanded blastocyst, no embryo observed hatching/hatced. The T2 embryos had more expanded blastocyst than T3 (P<0.05, hatching/hatched rate higher than T1 and T3 but lower than T4 (P<0.05. Shortly, KSOMaa enable to support 8-cell stage mice and hamster embryo, but the hamster embryo developed lower at expanded blastocyst stage. HECM-6 is more appropriate than KSOMaa to support 8-cell mice embryos development and suitable to develop 8-cell stage hamster embryos.

  14. Blastocyst Morphology Holds Clues Concerning The Chromosomal Status of The Embryo

    Directory of Open Access Journals (Sweden)

    Rita de Cassia Savio Figueira

    2015-07-01

    Full Text Available Background: Embryo morphology has been proposed as an alternative marker of chromosomal status. The objective of this retrospective cohort study was to investigate the association between the chromosomal status on day 3 of embryo development and blastocyst morphology. Materials and Methods: A total of 596 embryos obtained from 106 cycles of intracytoplasmic sperm injection (ICSI followed by preimplantation genetic aneuploidy screening (PGS were included in this retrospective study. We evaluated the relationship between blastocyst morphological features and embryonic chromosomal alteration. Results: Of the 564 embryos with fluorescent in situ hybridization (FISH results, 200 reached the blastocyst stage on day 5 of development. There was a significantly higher proportion of euploid embryos in those that achieved the blastocyst stage (59.0% compared to embryos that did not develop to blastocysts (41.2% on day 5 (P<0.001. Regarding blastocyst morphology, we observed that all embryos that had an abnormal inner cell mass (ICM were aneuploid. Embryos with morphologically normal ICM had a significantly higher euploidy rate (62.1%, P<0.001. As regards to the trophectoderm (TE morphology, an increased rate of euploidy was observed in embryos that had normal TE (65.8% compared to embryos with abnormal TE (37.5%, P<0.001. Finally, we observed a two-fold increase in the euploidy rate in high-quality blastocysts with both high-quality ICM and TE (70.4% compared to that found in low-quality blastocysts (31.0%, P<0.001. Conclusion: Chromosomal abnormalities do not impair embryo development as aneuploidy is frequently observed in embryos that reach the blastocyst stage. A high-quality blastocyst does not represent euploidy of chromosomes 13, 14, 15, 16, 18, 21, 22, X and Y. However, aneuploidy is associated with abnormalities in the ICM morphology. Further studies are necessary to confirm whether or not the transfer of blastocysts with low-quality ICM should be

  15. Gender determination of avian embryo

    Energy Technology Data Exchange (ETDEWEB)

    Daum, Keith A. (Idaho Falls, ID); Atkinson, David A. (Idaho Falls, ID)

    2002-01-01

    Disclosed is a method for gender determination of avian embryos. During the embryo incubation process, the outer hard shells of eggs are drilled and samples of allantoic fluid are removed. The allantoic fluids are directly introduced into an ion mobility spectrometer (IMS) for analysis. The resulting spectra contain the relevant marker peaks in the positive or negative mode which correlate with unique mobilities which are sex-specific. This way, the gender of the embryo can be determined.

  16. Analysis of electronic component inventory optimization in six stages supply chain management for warehouse with ABC using genetic algorithm and PSO

    Directory of Open Access Journals (Sweden)

    Ajay Singh Yadav

    2017-12-01

    Full Text Available The purpose of the proposed study is to give a new dimension on warehouse with artificial bee colony algorithm using genetic algorithm and particle swarm optimization algorithm processes in six stages - 11 member supply chain in electronic component inventory optimization to describe the certain and uncertain market demand which is based on supply reliability and to develop more realistic and more flexible models. We hope that the proposed study has a great potential to solve various practical tribulations related to the warehouse using genetic algorithm processes in six stages - 11 member supply chain in electronic component inventory optimization and also provide a general review for the application of soft computing techniques like genetic algorithms to use for improve the effectiveness and efficiency for various aspect of warehouse with artificial bee colony algorithm using genetic algorithm and particle swarm optimization algorithm.

  17. Effects of embryo-derived exosomes on the development of bovine cloned embryos.

    Science.gov (United States)

    Qu, Pengxiang; Qing, Suzhu; Liu, Ruiqi; Qin, Hongyu; Wang, Weiwei; Qiao, Fang; Ge, Hui; Liu, Jun; Zhang, Yong; Cui, Wei; Wang, Yongsheng

    2017-01-01

    The developmental competence of in vitro cultured (IVC) embryos is markedly lower than that of their in vivo counterparts, suggesting the need for optimization of IVC protocols. Embryo culture medium is routinely replaced three days after initial culture in bovine, however, whether this protocol is superior to continuous nonrenewal culture method under current conditions remains unclear. Using bovine somatic cell nuclear transfer (SCNT) embryos as the model, our results showed that compared with routine renewal treatment, nonrenewal culture system significantly improved blastocyst formation, blastocyst quality (increased total cell number, decreased stress and apoptosis, enhanced Oct-4 expression and ratio of ICM/TE), as well as following development to term. Existence and function of SCNT embryo-derived exosomes were then investigated to reveal the cause of impaired development induced by culture medium replacement. Exosomes were successfully isolated through differential centrifugation and identified by both electron microscopy and immunostaining against exosomal membrane marker CD9. Supplementation of extracted exosomes into freshly renewed medium significantly rescued not only blastocyst formation and quality (in vitro development), but also following growth to term (in vivo development). Notably, ratio of ICM/TE and calving rate were enhanced to a similar level as that in nonrenewal group. In conclusion, our results for the first time indicate that 1: bovine SCNT embryos can secrete exosomes into chemically defined culture medium during IVC; 2: secreted exosomes are essential for SCNT blastocyst formation, blastocyst quality, and following development to term; 3: removal of exosomes induced by culture medium replacement impairs SCNT embryo development, which can be avoided by nonrenewal culture procedure or markedly recovered by exosome supplementation.

  18. Determination of gene expression patterns using high-throughput RNA in situ hybridizaion to whole-mount Drosophila embryos

    Energy Technology Data Exchange (ETDEWEB)

    Weiszmann, R.; Hammonds, A.S.; Celniker, S.E.

    2009-04-09

    We describe a high-throughput protocol for RNA in situ hybridization (ISH) to Drosophila embryos in a 96-well format. cDNA or genomic DNA templates are amplified by PCR and then digoxigenin-labeled ribonucleotides are incorporated into antisense RNA probes by in vitro transcription. The quality of each probe is evaluated before ISH using a RNA probe quantification (dot blot) assay. RNA probes are hybridized to fixed, mixed-staged Drosophila embryos in 96-well plates. The resulting stained embryos can be examined and photographed immediately or stored at 4oC for later analysis. Starting with fixed, staged embryos, the protocol takes 6 d from probe template production through hybridization. Preparation of fixed embryos requires a minimum of 2 weeks to collect embryos representing all stages. The method has been used to determine the expression patterns of over 6,000 genes throughout embryogenesis.

  19. Who abandons embryos after IVF?

    LENUS (Irish Health Repository)

    Walsh, A P H

    2010-04-01

    This investigation describes features of in vitro fertilisation (IVF) patients who never returned to claim their embryos following cryopreservation. Frozen embryo data were reviewed to establish communication patterns between patient and clinic; embryos were considered abandoned when 1) an IVF patient with frozen embryo\\/s stored at our facility failed to make contact with our clinic for > 2 yrs and 2) the patient could not be located after a multi-modal outreach effort was undertaken. For these patients, telephone numbers had been disconnected and no forwarding address was available. Patient, spouse and emergency family contact\\/s all escaped detection efforts despite an exhaustive public database search including death records and Internet directory portals. From 3244 IVF cycles completed from 2000 to 2008, > or = 1 embryo was frozen in 1159 cases (35.7%). Those without correspondence for > 2 yrs accounted for 292 (25.2%) patients with frozen embryos; 281 were contacted by methods including registered (signature involving abandoned embryos did not differ substantially from other patients. The goal of having a baby was achieved by 10\\/11 patients either by spontaneous conception, adoption or IVF. One patient moved away with conception status unconfirmed. The overall rate of embryo abandonment was 11\\/1159 (< 1%) in this IVF population. Pre-IVF counselling minimises, but does not totally eliminate, the problem of abandoned embryos. As the number of abandoned embryos from IVF accumulates, their fate urgently requires clarification. We propose that clinicians develop a policy consistent with relevant Irish Constitutional provisions to address this medical dilemma.

  20. Antioxidants improve mouse preimplantation embryo development and viability.

    Science.gov (United States)

    Truong, Thi T; Soh, Yu May; Gardner, David K

    2016-07-01

    What is the effect of three antioxidants (acetyl-L-carnitine, N-acetyl-L-cysteine and α-lipoic acid), when used individually and in combination, on mouse embryo development in culture, and subsequent fetal development post-transfer? A combination of antioxidants resulted in significant increases in blastocyst cell number, maintained intracellular glutathione (GSH) levels, supported earlier cleavage times from 5-cell stage to expanded blastocyst, and improved fetal developmental irrespective of incubator oxygen concentration. Acetyl-L-carnitine, N-acetyl-L-cysteine and α-lipoic acid have been shown to have beneficial effects individually in several tissues, and most recently on developing embryos, in the presence of oxidative stress. Morphokinetics of mouse embryos were quantitated using time-lapse imaging. GSH levels in pronucleate oocytes were measured. Blastocysts underwent differential nuclear staining for inner cell mass and trophectoderm cells or were transferred to recipient females to assess implantation and fetal development. Pronucleate oocytes from F1 mice were cultured in 5 or 20% oxygen either individually or in groups of 10, in media G1/G2, in the presence or absence of 10 µM acetyl-L-carnitine /10 µM N-acetyl-L-cysteine /5 µM α-lipoic acid, either individually or in combination. Controls were embryos cultured without antioxidants. Intracellular levels of reduced glutathione were quantitated in pronucleate oocytes. Embryo development and viability were analysed through time-lapse microscopy and embryo transfers. Antioxidants significantly increased mouse blastocyst cell numbers compared with control when used individually (Pantioxidants resulted in faster development rates to 5-cell cleavage stage, which continued until the expanded blastocyst stage when cultured in 20% oxygen. The beneficial effects of combining the antioxidants were greater for embryos cultured individually as opposed to in groups of 10 and for those embryos cultured in 20

  1. Role of melatonin in embryo fetal development.

    Science.gov (United States)

    Voiculescu, S E; Zygouropoulos, N; Zahiu, C D; Zagrean, A M

    2014-01-01

    Melatonin is an indoleamine produced by the pineal gland and secreted in a circadian manner. In the past few decades, research over this topic has been enhanced. Melatonin has many important roles in the human physiology: regulator of the circadian rhythms, sleep inducer, antioxidant, anticarcinogenic. This paper reviews the involvement of melatonin in embryo fetal development. The pineal gland develops completely postpartum, so both the embryo and the fetus are dependent on the maternal melatonin provided transplacentally. Melatonin appears to be involved in the normal outcome of pregnancy beginning with the oocyte quality and finishing with the parturition. Its pregnancy night-time concentrations increase after 24 weeks of gestation, with significantly high levels after 32 weeks. Melatonin receptors are widespread in the embryo and fetus since early stages. There is solid evidence that melatonin is neuroprotective and has a positive effect on the outcome of the compromised pregnancies. In addition, chronodisruption leads to a reproductive dysfunction. Thus, the influence of melatonin on the developing human fetus may not be limited to the entertaining of circadian rhythmicity, but further studies are needed.

  2. Effect of sericin on preimplantation development of bovine embryos cultured individually.

    Science.gov (United States)

    Isobe, T; Ikebata, Y; Onitsuka, T; Wittayarat, M; Sato, Y; Taniguchi, M; Otoi, T

    2012-09-01

    The silk protein sericin has been identified as a potent antioxidant in mammalian cells. This study was conducted to examine the effects of sericin on preimplantation development and quality of bovine embryos cultured individually. When two-cell-stage embryos were cultured individually for 7 days in CR1aa medium supplemented with 0, 0.1, 0.5, or 1% sericin, rates of total blastocyst formation and development to expanded blastocysts from embryos cultured with 0.5% sericin were higher (P sericin. When embryos were cultured individually for 7 days in the CR1aa medium supplemented with 0 or 0.5% sericin under two oxidative stress conditions (50 or 100 μm H(2)O(2)), the addition of sericin significantly improved the blastocyst formation rate of embryos exposed to 100 μm H(2)O(2). However, the protective effect of sericin was not observed in development of embryos exposed to 50 μm H(2)O(2). When embryos were exposed to 100 μm H(2)O(2) during culture, the DNA fragmentation index of total blastocysts from embryos cultured with 0.5% sericin was lower than blastocysts derived from embryos cultured without sericin (4.4 vs. 6.8%; P sericin to in vitro culture medium improved preimplantation development and quality of bovine embryos cultured individually by preventing oxidative stress. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Nucleologenesis in the Caenorhabditis elegans embryo.

    Directory of Open Access Journals (Sweden)

    Darina Korčeková

    Full Text Available In the Caenorhabditis elegans nematode, the oocyte nucleolus disappears prior to fertilization. We have now investigated the re-formation of the nucleolus in the early embryo of this model organism by immunostaining for fibrillarin and DAO-5, a putative NOLC1/Nopp140 homolog involved in ribosome assembly. We find that labeled nucleoli first appear in somatic cells at around the 8-cell stage, at a time when transcription of the embryonic genome begins. Quantitative analysis of radial positioning showed the nucleolus to be localized at the nuclear periphery in a majority of early embryonic nuclei. At the ultrastructural level, the embryonic nucleolus appears to be composed of a relatively homogenous core surrounded by a crescent-shaped granular structure. Prior to embryonic genome activation, fibrillarin and DAO-5 staining is seen in numerous small nucleoplasmic foci. This staining pattern persists in the germline up to the ∼100-cell stage, until the P4 germ cell divides to give rise to the Z2/Z3 primordial germ cells and embryonic transcription is activated in this lineage. In the ncl-1 mutant, which is characterized by increased transcription of rDNA, DAO-5-labeled nucleoli are already present at the 2-cell stage. Our results suggest a link between the activation of transcription and the initial formation of nucleoli in the C. elegans embryo.

  4. A method for measuring the local gas pressure within a gas-flow stage in situ in the transmission electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Colby, R. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA (United States); Alsem, D.H. [Hummingbird Scientific, Lacey, WA (United States); Liyu, A.; Kabius, B. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA (United States)

    2015-06-15

    Environmental transmission electron microscopy (TEM) has enabled in situ experiments in a gaseous environment with high resolution imaging and spectroscopy. Addressing scientific challenges in areas such as catalysis, corrosion, and geochemistry can require pressures much higher than the ∼20 mbar achievable with a differentially pumped environmental TEM. Gas flow stages, in which the environment is contained between two semi-transparent thin membrane windows, have been demonstrated at pressures of several atmospheres. However, the relationship between the pressure at the sample and the pressure drop across the system is not clear for some geometries. We demonstrate a method for measuring the gas pressure at the sample by measuring the ratio of elastic to inelastic scattering and the defocus of the pair of thin windows. This method requires two energy filtered high-resolution TEM images that can be performed during an ongoing experiment, at the region of interest. The approach is demonstrated to measure greater than atmosphere pressures of N{sub 2} gas using a commercially available gas-flow stage. This technique provides a means to ensure reproducible sample pressures between different experiments, and even between very differently designed gas-flow stages. - Highlights: • Method developed for measuring gas pressure within a gas-flow stage in the TEM. • EFTEM and CTF-fitting used to calculate amount and volume of gas. • Requires only a pair of images without leaving region of interest. • Demonstrated for P > 1 atm with a common commercial gas-flow stage.

  5. A method for measuring the local gas pressure within a gas-flow stage in situ in the transmission electron microscope

    International Nuclear Information System (INIS)

    Colby, R.; Alsem, D.H.; Liyu, A.; Kabius, B.

    2015-01-01

    Environmental transmission electron microscopy (TEM) has enabled in situ experiments in a gaseous environment with high resolution imaging and spectroscopy. Addressing scientific challenges in areas such as catalysis, corrosion, and geochemistry can require pressures much higher than the ∼20 mbar achievable with a differentially pumped environmental TEM. Gas flow stages, in which the environment is contained between two semi-transparent thin membrane windows, have been demonstrated at pressures of several atmospheres. However, the relationship between the pressure at the sample and the pressure drop across the system is not clear for some geometries. We demonstrate a method for measuring the gas pressure at the sample by measuring the ratio of elastic to inelastic scattering and the defocus of the pair of thin windows. This method requires two energy filtered high-resolution TEM images that can be performed during an ongoing experiment, at the region of interest. The approach is demonstrated to measure greater than atmosphere pressures of N 2 gas using a commercially available gas-flow stage. This technique provides a means to ensure reproducible sample pressures between different experiments, and even between very differently designed gas-flow stages. - Highlights: • Method developed for measuring gas pressure within a gas-flow stage in the TEM. • EFTEM and CTF-fitting used to calculate amount and volume of gas. • Requires only a pair of images without leaving region of interest. • Demonstrated for P > 1 atm with a common commercial gas-flow stage

  6. Self-field effects on small-signal gain in two-stage free-electron lasers

    Indian Academy of Sciences (India)

    electron lasers. S JAFARI. ∗. , H MEHDIAN and A HASANBEIGI. Department of Physics and ... put power. This is particularly important for applications in which the radiation source is required to operate at high efficiency. For example, the tunability ...

  7. FACTOR MODEL ASSESSMENT OF THE COMPETITIVE INNOVATION CLUSTERS ELECTRONICS BASED ON ANALYSIS OF THE STAGES OF THEIR LIFE CYCLE

    Directory of Open Access Journals (Sweden)

    A. V. Brykin

    2013-01-01

    Full Text Available The cluster principle development in the world of electronics is one of the most effective examples of high-tech industry. The author considers the possibility of using clusters to modernize the Russian economy.

  8. Effect of the microenvironment and embryo density on developmental characteristics and gene expression profile of bovine preimplantative embryos cultured in vitro.

    Science.gov (United States)

    Hoelker, Michael; Rings, Franka; Lund, Qamaruddin; Ghanem, Nasser; Phatsara, Chirawath; Griese, Josef; Schellander, Karl; Tesfaye, Dawit

    2009-03-01

    The Well of the Well (WOW) system has been developed to culture embryos in small groups or to track the development of single embryos. In the present study, we aimed to examine the effects of the microenvironment provided by the WOW system and embryo density on developmental rates, embryo quality and preimplantative gene expression profile of the resulting embryos. Embryos cultured in a group of 16 reached the blastocyst stage at a significantly lower level than zygotes cultured in a group of 50 (22.2 vs 30.3%), whereas zygotes cultured in WOW were able to compensate against low embryo densities, reaching a blastocyst rate as high as embryos cultured in a group of 50 (31.3 vs 30.3%). Moreover, embryos derived from WOW culture did not differ in terms of differential cell counts and apoptotic cell index compared with controls. The gene expression analysis revealed 62 transcripts to be upregulated and 33 transcripts to be downregulated by WOW culture. Comparing the in vivo derived blastocysts with the blastocysts derived from WOW culture, and group culture, expression of ATP5A1, PLAC8 and KRT8 was more similar to the embryos derived from WOW culture, whereas expression of S100A10 and ZP3 genes was more similar to blastocysts cultured in a group. In conclusion, microenvironment as well as embryo density significantly affected developmental rates. While subsequent blastocysts did not differ in terms of differential cell counts and apoptotic cell index, significant differences were observed in terms of the relative abundance of transcripts in the resulting embryos.

  9. Embryos, genes, and birth defects

    National Research Council Canada - National Science Library

    Ferretti, Patrizia

    2006-01-01

    ... Structural anomalies The genesis of chromosome abnormalities Embryo survival The cause of high levels of chromosome abnormality in human embryos Relative parental risks - age, translocations, inversions, gonadal and germinal mosaics 33 33 34 35 36 44 44 45 4 Identification and Analysis of Genes Involved in Congenital Malformation Syndromes Peter J. Scambler Ge...

  10. Development of HY1 hybrid embryos between a cultivar of ...

    African Journals Online (AJOL)

    Reciprocal crosses between Phaseolus vulgaris and P. coccineus frequently lead to embryos abortion in all the developmental stages. However, the P. vulgaris NI637 cultivar and the wild form NI1108 of P. coccineus present abilities for combination. The abortion rate of pods is 93.93% when NI1108 is the maternal parent ...

  11. Gas exchange of the ostrich embryo during peak metabolism in ...

    African Journals Online (AJOL)

    Oxygen (O2) consumption and carbon dioxide (CO2) excretion of ostrich embryos were studied on 45 ostrich eggs in various stages of development. A closed respirometry system was used for eggs subjected to ????10 days of incubation, while an open flow system was used for older eggs. A total of 102 measurements ...

  12. Germination response of coconut ( Cocos nucifera L.) zygotic embryo

    African Journals Online (AJOL)

    The study investigated the effects of liquid and solid media in the propagation of coconut (Cocos nucifera) zygotic embryos at initiation stage. Eeuwen's medium supplemented with growth hormones naphthalene acetic acid ( NAA) and indole butyric acid (IBA) at different concentrations (0.5, 1.0, 1.5, 2.0 and 2.5mg/l) were ...

  13. Germination response of coconut (Cocos nucifera L.) zygotic embryo ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: The study investigated the effects of liquid and solid media in the propagation of coconut (Cocos nucifera) zygotic embryos at initiation stage. Eeuwen's medium supplemented with growth hormones naphthalene acetic acid ( NAA) and indole butyric acid (IBA) at different concentrations (0.5, 1.0, 1.5, 2.0 and ...

  14. Long-distance transportation of primate embryos developing in culture: a preliminary study.

    Science.gov (United States)

    Nichols, Stephanie; Harvey, Alexandra; Gierbolini, Lynette; Gonzalez-Martinez, Janis; Brenner, Carol; Bavister, Barry

    2010-03-01

    Non-human primate embryos are invaluable for conducting research relevant to human infertility and stem cells, but their availability is restricted. In this preliminary study, rhesus monkey embryos were produced by IVF at the Caribbean Primate Research Centre and shipped in tubes of gassed culture medium within a battery-powered transport incubator by overnight courier to Wayne State University in Michigan. Upon arrival, the embryos were incubated in fresh culture medium to evaluate further development. In 11 shipments comprising 98 cleavage-stage embryos developing from oocytes that were mature (MII) upon collection, 51 (52%) reached advanced preimplantation stages (morula to hatched blastocyst) during prolonged culture following transportation. However, most embryos produced from oocytes that were immature (MI) at collection arrested and only 5/51 (10%) reached advanced stages of development. This study demonstrates that non-cryopreserved primate embryos can be routinely transported between distant sites without loss of developmental ability. In this way, the processes of production and study of non-cryopreserved primate embryos need not be restricted to the same or nearby laboratories. This will expand the use of these embryos for research and facilitate generation of translationally relevant information. Published by Elsevier Ltd.

  15. Shared and unique patterns of embryo development in extremophile poeciliids.

    Directory of Open Access Journals (Sweden)

    Rüdiger Riesch

    Full Text Available Closely related lineages of livebearing fishes have independently adapted to two extreme environmental factors: toxic hydrogen sulphide (H(2S and perpetual darkness. Previous work has demonstrated in adult specimens that fish from these extreme habitats convergently evolved drastically increased head and offspring size, while cave fish are further characterized by reduced pigmentation and eye size. Here, we traced the development of these (and other divergent traits in embryos of Poecilia mexicana from benign surface habitats ("surface mollies" and a sulphidic cave ("cave mollies", as well as in embryos of the sister taxon, Poecilia sulphuraria from a sulphidic surface spring ("sulphur mollies". We asked at which points during development changes in the timing of the involved processes (i.e., heterochrony would be detectible.Data were extracted from digital photographs taken of representative embryos for each stage of development and each type of molly. Embryo mass decreased in convergent fashion, but we found patterns of embryonic fat content and ovum/embryo diameter to be divergent among all three types of mollies. The intensity of yellow colouration of the yolk (a proxy for carotenoid content was significantly lower in cave mollies throughout development. Moreover, while relative head size decreased through development in surface mollies, it increased in both types of extremophile mollies, and eye growth was arrested in mid-stage embryos of cave mollies but not in surface or sulphur mollies.Our results clearly demonstrate that even among sister taxa convergence in phenotypic traits is not always achieved by the same processes during embryo development. Furthermore, teleost development is crucially dependent on sufficient carotenoid stores in the yolk, and so we discuss how the apparent ability of cave mollies to overcome this carotenoid-dependency may represent another potential mechanism explaining the lack of gene flow between surface and

  16. Shared and unique patterns of embryo development in extremophile poeciliids.

    Science.gov (United States)

    Riesch, Rüdiger; Schlupp, Ingo; Langerhans, R Brian; Plath, Martin

    2011-01-01

    Closely related lineages of livebearing fishes have independently adapted to two extreme environmental factors: toxic hydrogen sulphide (H(2)S) and perpetual darkness. Previous work has demonstrated in adult specimens that fish from these extreme habitats convergently evolved drastically increased head and offspring size, while cave fish are further characterized by reduced pigmentation and eye size. Here, we traced the development of these (and other) divergent traits in embryos of Poecilia mexicana from benign surface habitats ("surface mollies") and a sulphidic cave ("cave mollies"), as well as in embryos of the sister taxon, Poecilia sulphuraria from a sulphidic surface spring ("sulphur mollies"). We asked at which points during development changes in the timing of the involved processes (i.e., heterochrony) would be detectible. Data were extracted from digital photographs taken of representative embryos for each stage of development and each type of molly. Embryo mass decreased in convergent fashion, but we found patterns of embryonic fat content and ovum/embryo diameter to be divergent among all three types of mollies. The intensity of yellow colouration of the yolk (a proxy for carotenoid content) was significantly lower in cave mollies throughout development. Moreover, while relative head size decreased through development in surface mollies, it increased in both types of extremophile mollies, and eye growth was arrested in mid-stage embryos of cave mollies but not in surface or sulphur mollies. Our results clearly demonstrate that even among sister taxa convergence in phenotypic traits is not always achieved by the same processes during embryo development. Furthermore, teleost development is crucially dependent on sufficient carotenoid stores in the yolk, and so we discuss how the apparent ability of cave mollies to overcome this carotenoid-dependency may represent another potential mechanism explaining the lack of gene flow between surface and cave

  17. Expression of microRNAs in bovine and human pre-implantation embryo culture media

    Science.gov (United States)

    Kropp, Jenna; Salih, Sana M.; Khatib, Hasan

    2014-01-01

    MicroRNAs (miRNA) are short non-coding RNAs which act to regulate expression of genes driving numerous cellular processes. These RNAs are secreted within exosomes from cells into the extracellular environment where they may act as signaling molecules. In addition, they are relatively stable and are specifically expressed in association to certain cancers making them strong candidates as biological markers. Moreover, miRNAs have been detected in body fluids including urine, milk, saliva, semen, and blood plasma. However, it is unknown whether they are secreted by embryonic cells into the culture media. Given that miRNAs are expressed throughout embryonic cellular divisions and embryonic genome activation, we hypothesized that they are secreted from the embryo into the extracellular environment and may play a role in the developmental competence of bovine embryos. To test this hypothesis, bovine embryos were cultured individually from day 5 to day 8 of development in an in vitro fertilization system and gene expression of 5 miRNAs was analyzed in both embryos and culture media. Differential miRNA gene expression was observed between embryos that developed to the blastocyst stage and those that failed to develop from the morula to blastocyst stage, deemed degenerate embryos. MiR-25, miR-302c, miR-196a2, and miR-181a expression was found to be higher in degenerate embryos compared to blastocyst embryos. Interestingly, these miRNAs were also found to be expressed in the culture media of both bovine and human pre-implantation embryos. Overall, our results show for the first time that miRNAs are secreted from pre-implantation embryos into culture media and that miRNA expression may correlate with developmental competence of the embryo. Expression of miRNAs in in vitro culture media could allow for the development of biological markers for selection of better quality embryos and for subsequent successful pregnancy. PMID:24795753

  18. A Review of the Teratogenic Factors Effect on Embryo

    Directory of Open Access Journals (Sweden)

    Manzarbanoo Shojaei fard

    2017-02-01

    Full Text Available Background & Objectives: Teratology is a branch of embryology science that studies causes, mechanisms and abnormal pattern development. Embryo growth traumatic factors during pregnancy are called teratogens that some teratogens pass the placental barrier and cause adverse effect during development stages and malformation, however a drug may improve general health of the mother, but it might be poisonous for embryo and cause diverse malformation. Since study of embryo health and risk factor in this stage is important, the aim of this review article was the investigation of some types of teratosgens (such as radiation, infectious agents, heat disorders, maternal conditions and particularly the effect of teratogenic drugs on embryo including some legal drugs (such as acetaminophen, thalidomide, acyclovir, sedatives and anticonvulsants and illegal drugs (such as nicotine, alcohol, cocaine and marijuana. Conclusion: In general, teratogens depending on the type and duration of exposure in pregnancyperiod, adversely affect embryo and cause various disorders. A better understanding of these teratogens can contribute to prevent these defects, since many other drugs with similar effects and lower teratogenicity can be used to improve mothers’ health.

  19. Development and quality of porcine parthenogenetically activated embryos after removal of zona pellucida

    DEFF Research Database (Denmark)

    Li, Rong; Liu, Ying; Pedersen, Hanne Skovsgaard

    2013-01-01

    The need of the zona pellucida (ZP) for in vitro development is controversial because it might be an obstacle to hatching of the blastocyst. This study investigated the development and quality of porcine parthenogenetically activated (PA) embryos by observation of the developmental kinetics...... of developmental percentages and occurrence of apoptosis on Day 6 and Day 7 (Time of PA, Day 0); and (3) investigation of the robustness of embryos using vitrification on Day 4. The developmental kinetics showed that there was a general trend for zona-free PA embryos to develop faster than zona intact PA embryos...... at all developmental stages, but the difference was only significant at the five-cell stage. When compared with development of zona-intact embryos, ZP removal decreased the overall blastocyst percentage (83.9 ± 2.0 vs. 72.5 ± 2.9, respectively) and especially the percentage of good morphology (grades 1...

  20. Is there a link between blastomere contact surfaces of day 3 embryos and live birth rate?

    Directory of Open Access Journals (Sweden)

    Paternot Goedele

    2012-09-01

    Full Text Available Abstract Background Cell-cell communication and adhesion are essential for the compaction process of early stage embryos. The aim of this study was to develop a non-invasive objective calculation system of embryo compaction in order to test the hypothesis that embryos with a larger mean contact surface result in a higher live birth rate compared to embryos with a lower mean contact surface. Methods Multilevel images of 474 embryos transferred on day 3 were evaluated by the Cellify software. This software calculates the contact surfaces between the blastomeres. The primary outcome of this study was live birth. An ideal range of contact surface was determined and the positive and negative predictive value, the sensitivity, the specificity and the area under the curve for this new characteristic were calculated. Results In total, 115 (24% transferred embryos resulted in a live birth. Selection of an embryo for transfer on its mean contact surface could predict live birth with a high sensitivity (80% and high negative predicting value (83% but with a low positive predictive value (27%, a low specificity (31% and low area under the ROC curve (0.56. The mean contact surface of embryos cultured in a single medium was significantly higher compared to the mean contact surface of embryos cultured in a sequential medium (p = 0.0003. Conclusions Neither the mean contact surface nor the number of contact surfaces of a day 3 embryo had an additional value in the prediction of live birth. The type of culture medium, however, had an impact on the contact surface of an embryo. Embryos cultured in a single medium had a significant larger contact surface compared to embryos cultured in the sequential medium.

  1. Osmotic measurements in whole megagametophytes and embryos of loblolly pine (Pinus taeda) during seed development.

    Science.gov (United States)

    Pullman, Gerald S; Johnson, Shannon

    2009-06-01

    Water potential (Psi) and osmotic potential (Psis) were measured weekly through the sequence of seed development in megagametophytes of loblolly pine (Pinus taeda L.). A Wescor 5500XRS vapor pressure osmometer, modified with a cycle hold switch, was used to measure Psi for whole megagametophytes containing embryos. The Psi measurements for megagametophytes with embryos removed were also attempted but readings were distorted due to cell lysates from the cut surfaces. Six seasonal sets of megagametophyte Psi profiles were generated. Megagametophytes from most of the trees examined showed a consistent Psi pattern: low measurements of -1.0 to -0.75 MPa during early embryo development in late June to early July when embryo Stages 1-2 occur; an increase for one to several weeks to levels of -0.5 to -0.75 MPa, beginning at Stages 3-5 when apical dome formation occurs; followed by a steady drop from -0.85 to -1.7 to -2.0 MPa from Stage 6 onward from late August until just before cone seed release. The Psis was measured for supernatant from centrifuged frozen-thawed megagametophyte tissue (embryos removed). Megagametophyte Psis profiles were similar for seeds analyzed from two trees and resembled Psi observations starting low, rising around Stages 4-7 and then undergoing a major reduction indicating a strong solute accumulation beginning at Stages 7-9.1. Somatic embryos stop growth prematurely in vitro at Stages 8-9.1. The major change in the accumulation of megagametophyte solutes at Stages 8-9.1 correlates with the halt in somatic embryo maturation and suggests that identifying, quantifying and using the major natural soluble compounds that accumulate during mid- to late-stage seed development may be important to improve conifer somatic embryo maturation.

  2. Silver Nanoparticles Incite Size and Dose-Dependent Developmental Phenotypes and Nanotoxicity in Zebrafish Embryos

    Science.gov (United States)

    Browning, Lauren M.; Lee, Kerry J.; Nallathamby, Prakash D.; Xu, Xiao-Hong Nancy

    2013-01-01

    Nanomaterials possess distinctive physicochemical properties and promise a wide range of applications, from advanced technology to leading-edge medicine. However, their effects on living organisms remain largely unknown. Here we report that the purified silver nanoparticles (Ag NPs, 97 ± 13 nm) incite specific developmental stage embryonic phenotypes and nanotoxicity in a dose-dependent manner, upon acute exposure of given-stage embryos to the NPs (0–24 pM) for only 2 h. The critical concentrations of the NPs that cause 50% of embryos develop normally for cleavage, early-gastrula, early-segmentation, late-segmentation, and hatching stage zebrafish embryos are 3.5, 4, 6, 6, and 8 pM, respectively, showing that the earlier developmental stage embryos are much more sensitive to the effects of the NPs than the later stage. Interestingly, distinctive phenotypes (head abnormality and no eyes) are observed only in cleavage and early-gastrula stage embryos treated with the NPs, showing the stage-specific effects of the NPs. By comparing with our study of the smaller Ag NPs (13.1 ± 2.5 nm), we found that the embryonic phenotypes strikingly depend upon the sizes of Ag NPs and embryonic developmental stages. These notable findings suggest that the Ag NPs are unlike any conventional chemicals or ions. They can potentially enable target specific study and therapy for early embryonic development in size, stage, dose, and exposure-duration dependent manners. PMID:24024906

  3. In Vitro Embryo as a Person

    Directory of Open Access Journals (Sweden)

    محمد حسن صادقی مقدم

    2016-03-01

    Full Text Available Based on moral principles and the natural laws, an in vitro embryo is considered as a natural embryo. The difference in the course of natural growing of an in vitro embryo and natural embryo, does not result in a difference of the governing rules, since both are embryos. It is argued that an in vitro embryo has the same rights as the natural embryo. Considering this claim, despite the position of some scholars who believe that such an embryo is subject to ownership, this article aims to critique this idea and argue that an in vitro embryo has the same personhood as a natural embryo from the moment of conception. Therefore, the embryo cannot be transferred as a gift or otherwise traded in the form of a stipulation in a contract.

  4. Correlating Metastable-Atom Density, Reduced Electric Field, and Electron Energy Distribution in the Initiation, Transient, and Post-Transient Stages of a Pulsed Argon Discharge

    Science.gov (United States)

    Franek, James B.

    Argon emission lines, particularly those in the near-infrared region (700-900nm), are used to determine plasma properties in low-temperature, partially ionized plasmas to determine effective electron temperature [Boffard et al., 2012], and argon excited state density [Boffard et al., 2009] using appropriately assumed electron energy distributions. While the effect of radiation trapping influences the interpretation of plasma properties from emission-line ratio analysis, eliminating the need to account for these effects by directly observing the 3px-to-1sy transitions [ Boffard et al., 2012] is preferable in most cases as this simplifies the analysis. In this dissertation, a 1-Torr argon, pulsed positive column in a hollow-cathode discharge is used to study the correlation between four quantities: 420.1-419.8nm emission-line ratio, metastable-atom density, reduced electric field, and electron energy distribution. The extended coronal model is used to acquire an expression for 420.1-419.8nm emission-line ratio, which is sensitive to direct electron-impact excitation of argon excited states as well as stepwise electron-impact excitation of argon excited states for the purpose of inferring plasma quantities from experimental measurements. Initial inspection of the 420.1-419.8nm emission-line ratio suggests the pulse may be empirically divided into three distinct stages labelled the Initiation Stage, Transient Stage, and Post-Transient stage. Using equilibrium electron energy distributions from simulation to deduce excitation rates [Adams et al., 2012] in the extended coronal model affords agreement between predicted and observed metastable density in the Post-Transient stage of the discharge [Franek et al., 2015]. Applying this model-assisted diagnostic technique to the characterization of plasma systems utilizing lower-resolution spectroscopic systems is not straightforward, however, as the 419.8nm and 420.1nm emission-line profiles are convolved and become

  5. Preimplantation development of cloned canine embryos recovered by hysterectomy or surgical uterine flushing and subsequent pregnancy outcomes.

    Science.gov (United States)

    Jeong, Yeon Woo; Kim, Joung Joo; Kim, Hyun Duk; Hwang, Kyu Chan; Hyun, Sang Hwan; Kim, Nam-Hyung; Jeung, Eui-Bae; Hwang, Woo Suk

    2016-11-01

    Dog cloning offers a substantial potential because of the advancements in assisted reproductive technology and development of the human disease model in line with the transgenic technique. However, little is known about the development of the canine cloned embryo during the preimplantation period. The aim of this study was to investigate the most efficient method and time for collecting cloned canine preimplantation embryos and to ascertain the developmental timeline of cloned canine embryos. Two hundred cloned embryos were created and transferred into 11 surrogates. The preimplantation stage cloned embryos were then collected on Days 7, 8, and 9 using an ovariohysterectomy or the Foley balloon catheter method. The recovery rate of reconstructed embryos was 63.6% and 60.6% for the ovariohysterectomy and Foley balloon catheter methods, respectively. Although significant differences were observed in the early developmental stages (one-cell and 16-cell stages), no significant difference was observed in the blastocyst stage. Significantly higher blastocyst rate was observed when the embryos were collected on Day 8 (11.4%) than on Day 7 (0.0%; P cloned embryos can develop to blastocysts by Day 8, and full-term pregnancy can be achieved after embryo transfer in canine. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Self-field effects on small-signal gain in two-stage free-electron lasers

    Indian Academy of Sciences (India)

    efficiency in strong optical fields. Axially nonuniform magnetic fields are important for enhancing the extraction efficiency in free-electron lasers. The experimental observation of efficiency enhancement by linearly tapering the last quarter of the 10 m NISUS un- dulator at the NSLS-SDL was reported by Watanabe et al [12].

  7. An electron-microscopical analysis of capture and initial stages of penetration of nematodes by Arthrobotrys oligospora

    NARCIS (Netherlands)

    Veenhuis, Marten; Nordbring-Hertz, Birgit; Harder, Wim

    1985-01-01

    A detailed analysis was made of the capture and subsequent penetration of nematodes by the nematophagous fungus Arthrobotrys oligospora using different electron-microscopical techniques. Capture of nematodes by this fungus occurred on complex hyphal structures (traps) and was effectuated by an

  8. Effect of medium salt concentration on differentiation and maturation of somatic embryos of cassava (Manihot esculenta Crantz).

    Science.gov (United States)

    Groll, J; Mycock, D J; Gray, V M

    2002-05-01

    Culture of cassava somatic embryos on media with an altered macro- and micro-nutrient salt concentration affected embryo development and germination capability. In the tests, quarter-, half-, full- or double-strength Murashige and Skoog (MS) media were compared. The maximum number of somatic embryos differentiated from a proliferative nodular embryogenic callus (NEC) on either half- or full-strength MS medium, and the greatest numbers of cotyledonary stage embryos were formed on full-strength MS medium. Developed somatic embryos were then desiccated above a saturated K2SO4 solution for 10 d. After transfer to germination medium, embryos that had developed on half- and full-strength MS medium yielded 8.3 and 8.6 germinants g(-1) NEC tissue, respectively. For this important but often disregarded culture factor, either half- or full-strength MS medium is recommended for both the differentiation and development of cassava somatic embryos that are capable of germination.

  9. Hot-electron generation by “cavitating” Langmuir turbulence in the nonlinear stage of the two-plasmon–decay instability

    International Nuclear Information System (INIS)

    Vu, H. X.; DuBois, D. F.; Russell, D. A.; Myatt, J. F.

    2012-01-01

    The kinetic reduced-description particle-in-cell simulation technique has been applied to study the nonlinear stage of two-plasmon–decay (TPD) instability in an inhomogeneous plasma driven by crossed laser beams. The TPD instability is found to be a prolific generator of “cavitating” Langmuir turbulence. Langmuir “cavitons”—localized longitudinal electric fields, oscillating near the local electron plasma frequency, trapped in ponderomotive density depressions—collapse to dimensions of a few electron Debye lengths, where the electric field energy is collisionlessly transferred to electron kinetic energy. The resulting hot electrons can attain instantaneous temperatures up to 100 keV with net suprathermal heat flux out of the system of up to a few percent of the input laser energy. Scaling laws for this hot-electron generation by TPD, in regimes motivated by recent experiments on the Omega laser, were presented recently by Vu et al. (H. X. Vu, D. F. DuBois, D. A. Russell, and J. F. Myatt, Phys. Plasmas 19, 102703 (2012)). This paper concentrates on the microscopic mechanisms for hot-electron generation. The spatial distribution of the maxima of the electric field envelope modulus is found to be very spiky, with the distribution of electric field envelope maxima obeying Gaussian statistics. The cavitons are produced in density-depletion trenches produced by the combined ponderomotive interference of the crossed laser beams and the ponderomotive beats of the primary backward-going TPD Langmuir waves (LWs) resulting from the crossed beams. The Langmuir turbulence is strongest in the electron-density region near 0.241× the laser's critical density, where the forward LWs from the crossed-beam TPD are degenerate. Nucleation of cavitons is assisted by the modulation of the electron density in the trenches, which in turn is caused by the beating of the common forward-going LW and the pair of backward-going LWs. The autocorrelation function of the LW envelope

  10. Contrasting Storage Protein Synthesis and Messenger RNA Accumulation during Development of Zygotic and Somatic Embryos of Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Krochko, J E; Pramanik, S K; Bewley, J D

    1992-05-01

    During development on hormone-free media, somatic embryos pass through distinct morphological stages that superficially resemble those of zygotic embryo development (globular, heart, torpedo, cotyledonary stages). Despite these similarities, they differ from zygotic embryos in the extent of cotyledonary development and the patterns of synthesis and quantitative expression of seed-specific storage proteins (7S, 11S, and 2S proteins). Alfin (7S) is the first storage protein synthesized in developing zygotic embryos (stage IV). The 11S (medicagin) and 2S (Low Molecular Weight, LMW) storage proteins are not detectable until the following stage of development (stage V), although all three are present before the completion of embryo enlargement. Likewise, the 7S storage protein is the first to be synthesized in developing somatic embryos (day 5). Medicagin is evident by day 7 and the LMW protein by day 10. In contrast to zygotic embryos, alfin remains the predominant storage protein in somatic embryos throughout development. Not only are the relative amounts of medicagin and the LMW protein reduced in somatic embryos but the LMW protein is accumulated much later than the other proteins. Quantification of the storage protein mRNAs (7S, 11S, and 2S) by northern blot analysis confirms that there are substantial differences in the patterns of message accumulation in zygotic and somatic embryos of alfalfa (Medicago sativa). In zygotic embryos, the 7S, 11S, and 2S storage protein mRNAs are abundant during maturation and, in particular, during the stages of maximum protein synthesis (alfin, stages VI and VII; medicagin, stage VII; LMW, stage VII). In somatic embryos, the predominance of the 7S storage protein is correlated with increased accumulation of its mRNA, whereas the limited synthesis of the 11S storage protein is associated with much lower steady-state levels of its message. The mRNA for the LMW protein is present already by 3 days after transfer to hormone-free media

  11. X-Ray Production by Cascading Stages of a High-Gain Harmonic Generation Free-Electron Laser I: Basic Theory

    Energy Technology Data Exchange (ETDEWEB)

    Wu, J

    2004-07-02

    We study a new approach to produce x-ray by cascading several stages of a High-Gain Harmonic Generation (HGHG) Free-Electron Laser (FEL). Besides the merits of a Self-Amplified Spontaneous Emission (SASE) scheme, an HGHG scheme could also provide much better stability of the radiation power, controllable short pulse length, more stable central wavelength, and radiation with better longitudinal coherence. Detailed design and optimization scheme, simulation results and analytical estimate formulae are presented. To lay results on a realistic basis, the electron bunch parameters used in this paper are restricted to be those of DESY TTF and SLAC LCLS projects; however, such sets of parameters are not necessary to be optimized for an HGHG FEL.

  12. Simulator program as a form of implementation of electronic teaching tools for self-study of foreign students at the stage of pre-university training

    Directory of Open Access Journals (Sweden)

    Andriy O. Savel'ev

    2015-06-01

    Full Text Available Questions of empowerment the organization of classroom and extracurricular self-study of foreign students at the stage of pre-university training through the implementation of electronic teaching tools as a component of computer training facilities in educational process are considered. Classification of modern electronic teaching tools as a component of computer hardware training, developed on the basis of modern information and communication technologies is offered. Version of program-simulator "Introductory course" is offered. The program is created by means of WEB-programming and uses training material of introductory course. Introductory course is one of the most important elements of teaching of scientific style of speech within the language training for the foreign students at the preparatory faculty.

  13. Effects of Insulin-like Growth Factor-1 on Development of Somatic Cell Cloned Bovine Embryos.

    Science.gov (United States)

    Qu, Pengxiang; Li, Yanyan; Deng, Tengfei; Jia, Dan; Qing, Suzhu; Su, Jianmin; Zhang, Yong; Wang, Yongsheng

    2016-06-01

    The aim of this study was to assess the effect of insulin-like growth factor-1 (IGF-1) on the developmental competence of somatic cell nuclear transfer (SCNT) bovine embryos. First, the expression levels of IGF-1 receptor (IGF-1R) and IGF-1 in the oocytes and embryos of different developmental stages were examined. Then the effects of exogenous IGF-1 on the development of SCNT embryos were evaluated both in vitro and in vivo. The results showed that IGF-1 was not expressed in both IVF and SCNT embryos, whereas IGF-1R could be detected throughout the preimplantation stages in both protein and mRNA levels. Also, exogenous IGF-1 had no obvious impact on the developmental competence of IVF embryos. However, it could improve the developmental competence of SCNT embryos in terms of blastocyst developmental rate (31.3% vs. 43.2%, p embryo transfer, there was an upward tendency in both examined terms in the IGF-1-supplemented group when compared with the control group. In conclusion, the present study showed that supplementing exogenous IGF-1 to the culture medium has an obvious positive effect on the development competence of SCNT embryos.

  14. Developmental toxicity and oxidative stress induced by gamma irradiation in zebrafish embryos

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Miao; Hu, Nan; Ding, Dexin; Zhao, Weichao; Feng, Yongfu; Zhang, Hui; Li, Guangyue; Wang, Yongdong [University of South China, Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, Hengyang, Hunan Province (China)

    2016-11-15

    This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1-1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner. (orig.)

  15. Developmental toxicity and oxidative stress induced by gamma irradiation in zebrafish embryos.

    Science.gov (United States)

    Hu, Miao; Hu, Nan; Ding, Dexin; Zhao, Weichao; Feng, Yongfu; Zhang, Hui; Li, Guangyue; Wang, Yongdong

    2016-11-01

    This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1-1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner.

  16. PXD101 significantly improves nuclear reprogramming and the in vitro developmental competence of porcine SCNT embryos

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jun-Xue; Kang, Jin-Dan; Li, Suo; Jin, Long; Zhu, Hai-Ying; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun, E-mail: yinxj33@msn.com

    2015-01-02

    Highlights: • First explored that the effects of PXD101 on the development of SCNT embryos in vitro. • 0.5 μM PXD101 treated for 24 h improved the development of porcine SCNT embryos. • Level of AcH3K9 was significantly higher than control group at early stages. - Abstract: In this study, we investigated the effects of the histone deacetylase inhibitor PXD101 (belinostat) on the preimplantation development of porcine somatic cell nuclear transfer (SCNT) embryos and their expression of the epigenetic markers histone H3 acetylated at lysine 9 (AcH3K9). We compared the in vitro developmental competence of SCNT embryos treated with various concentrations of PXD101 for 24 h. Treatment with 0.5 μM PXD101 significantly increased the proportion of SCNT embryos that reached the blastocyst stage, in comparison to the control group (23.3% vs. 11.5%, P < 0.05). We tested the in vitro developmental competence of SCNT embryos treated with 0.5 μM PXD101 for various amounts of times following activation. Treatment for 24 h significantly improved the development of porcine SCNT embryos, with a significantly higher proportion of embryos reaching the blastocyst stage in comparison to the control group (25.7% vs. 10.6%, P < 0.05). PXD101-treated SCNT embryos were transferred into two surrogate sows, one of whom became pregnant and four fetuses developed. PXD101 treatment significantly increased the fluorescence intensity of immunostaining for AcH3K9 in embryos at the pseudo-pronuclear and 2-cell stages. At these stages, the fluorescence intensities of immunostaining for AcH3K9 were significantly higher in PXD101-treated embryos than in control untreated embryos. In conclusion, this study demonstrates that PXD101 can significantly improve the in vitro and in vivo developmental competence of porcine SCNT embryos and can enhance their nuclear reprogramming.

  17. Estagiamento de embriões de Macrobrachium olfersi (Wiegman (Crustacea, Palaemonidae através de critérios morfológicos nos dias embrionários Macrobrachium olfersi (Wiegman (Crustacea, Palaemonidae embryo staging through morphological landmarks identified in each embryonic day

    Directory of Open Access Journals (Sweden)

    Marcos S. Simões-Costa

    2005-06-01

    was characterized through daily staging system. Living and fixed embryos were analyzed (48x in intervals of 24 hours (embryonic day. The eye index was calculated in each embryonic day from the appearance of the eye pigmentation. The development of M. olfersi was described in 14 embryonic days (E, where the cleavage, gastrulation, germinal disk and egg nauplius are developed from E1 to E4. The subsequent days were characterized by the growth of the egg nauplius, as well by the formation and the bent of the post-nauplius. At E7, the eye pigmentation appeared and was followed by the beginning of heartbeats at E8. From E9 to E14, more intensive organogenesis processes occurred, mainly on the nervous, cardiac and digestive systems. The daily staging of development of M. olfersi development enabled the recognition of different embryonic forms, as well as growth and differentiation rhythms of embryo, which were fundamental to the gradual formation of the body plan.

  18. Oxygen diffusion in fish embryos

    NARCIS (Netherlands)

    Kranenbarg, S.

    2002-01-01

    All vertebrate embryos pass through a developmental period of remarkably low morphological variability. This period has been called phylotypic period. During the phylotypic period, organogenesis takes place, including blood vessel development. Before the phylotypic

  19. The MARVEL domain protein, Singles Bar, is required for progression past the pre-fusion complex stage of myoblast fusion.

    Science.gov (United States)

    Estrada, Beatriz; Maeland, Anne D; Gisselbrecht, Stephen S; Bloor, James W; Brown, Nicholas H; Michelson, Alan M

    2007-07-15

    Multinucleated myotubes develop by the sequential fusion of individual myoblasts. Using a convergence of genomic and classical genetic approaches, we have discovered a novel gene, singles bar (sing), that is essential for myoblast fusion. sing encodes a small multipass transmembrane protein containing a MARVEL domain, which is found in vertebrate proteins involved in processes such as tight junction formation and vesicle trafficking where--as in myoblast fusion--membrane apposition occurs. sing is expressed in both founder cells and fusion competent myoblasts preceding and during myoblast fusion. Examination of embryos injected with double-stranded sing RNA or embryos homozygous for ethane methyl sulfonate-induced sing alleles revealed an identical phenotype: replacement of multinucleated myofibers by groups of single, myosin-expressing myoblasts at a stage when formation of the mature muscle pattern is complete in wild-type embryos. Unfused sing mutant myoblasts form clusters, suggesting that early recognition and adhesion of these cells are unimpaired. To further investigate this phenotype, we undertook electron microscopic ultrastructural studies of fusing myoblasts in both sing and wild-type embryos. These experiments revealed that more sing mutant myoblasts than wild-type contain pre-fusion complexes, which are characterized by electron-dense vesicles paired on either side of the fusing plasma membranes. In contrast, embryos mutant for another muscle fusion gene, blown fuse (blow), have a normal number of such complexes. Together, these results lead to the hypothesis that sing acts at a step distinct from that of blow, and that sing is required on both founder cell and fusion-competent myoblast membranes to allow progression past the pre-fusion complex stage of myoblast fusion, possibly by mediating fusion of the electron-dense vesicles to the plasma membrane.

  20. Determination of escin content in androgenic embryos and hairy root culture of Aesculus hippocastanum.

    Science.gov (United States)

    Calić-Dragosavac, Dusica; Zdravković-Korać, Snezana; Savikin-Fodulović, Katarina; Radojević, Ljiljana; Vinterhalter, Branka

    2010-05-01

    Escin, a group of chemically related triterpenic glycosides, is widely used in commercial preparations for the treatment of venous insufficiency. Since the zygotic embryo cotyledons accumulate the highest amount of escin, it is currently extracted from the seeds of horse chestnut, Aesculus hippocastanum L. (Hippocastanaceae), on a large scale. As this material is available during only short period of the year, we studied the possibility of using plant tissue culture to obtain escin. For this purpose, the content of escin in androgenic embryos and hairy root cultures of horse chestnut was studied. Escin content was found to be dependent on the stage of androgenic embryo development and the type of phytoregulator supplemented to the nutritive medium. In the absence of phytoregulators, androgenic embryos at the globular stage of development contained approximately four times less escin than those at the cotyledonary stage. Inclusion of various phytoregulators in the nutritive media stimulated escin production. Among them, 2,4-dichlorophenoxyacetic acid (2,4-D) showed the most pronounced effect, with escin content almost reaching that found in zygotic embryos (6.77% versus 6.96%). Two hairy root clones produced substantial amounts of escin (3.57% and 4.09%), less than zygotic embryos, but higher than cotyledonary embryos on phytoregulator-free medium.

  1. Three-dimensional anatomy of the Ciona intestinalis tailbud embryo at single-cell resolution.

    Science.gov (United States)

    Nakamura, Mitsuru J; Terai, Jun; Okubo, Reiko; Hotta, Kohji; Oka, Kotaro

    2012-12-15

    During embryogenesis, chordates pass through a tailbud stage in which the larval tail is formed. Since acquisition of a tadpole-like tail during tailbud stage is one of the key events in the evolution of chordates, understanding the anatomy of the tailbud stage chordate embryo is of special interest. In this study, to understand comprehensively the anatomy of the tailbud embryo at single-cell-level, real microscopic image stacks of the tailbud embryo in Ciona intestinalis were reconstructed into a 3D computer model. This comprehensive 3D model of the ascidian tailbud embryo was based on real images of confocal laser scanning microscope (CLSM) and therefore, cell shape, location and cell arrangement reflect real geometries of the tailbud embryo. We found that the tailbud embryo consists of 1579 cells, including 836 epidermal cells, 228 cells in the central nervous system, 218 mesenchymal cells, four trunk ventral cells, two B/B(⁎)8.11 cells, 36 muscle cells, 40 notochord cells, four primordial germ cells, and 199 endodermal cells. Moreover, we identified for the first time two populations of previously undefined cells (a total of 12 cells) in Ciona: one located in the lateral trunk and the other located under the tail dorsal epidermis. This information provides a first step for understanding how the body plan of the chordate tailbud embryo formed and evolved. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Establishing some Correlations between Certain Morphometric Parameters and Embryo Quality

    Directory of Open Access Journals (Sweden)

    Nicolae Păcală

    2011-05-01

    Full Text Available The aim of this paper was to establish some correlations between certain morphometric parameters and embryo quality. The morphometric parameters taken into consideration were: zona pellucida thickness, outer and inner diameter, and outer and inner perimeter. For experiments we used embryos recovered at 24 hours from mouse females superovulated with gonadotrope hormones (eCG and hCG. The embryos recovered were cultivated in KSOM media, supplemented with amino acids, and during the in vitro cultivation they were measured at different time intervals for establishing morphometric parameters. The data obtained were statistically analyzed using Minitab 15, using Fitted Line Plot regression that allows testing of the linear and polynomial regression of one variable. After statistical analyze of the data we found that the thickness of the zona pellucida can constitute a morphometric parameter that can be used as an indicator of subsequent development of the 2 cell embryos to morula and blastocyst stage respectively. The other morphometric parameters studied (outer and inner diameter, and outer and inner perimeter cannot be used as indicators of the embryo development.

  3. Pro-apoptotic Effect of Pifithrin-α on Preimplantation Porcine Fertilized Embryo Development

    Directory of Open Access Journals (Sweden)

    Brendan Mulligan

    2012-12-01

    Full Text Available The aim of this study was to investigate the impact of a reported p53 inhibitor, pifithrin-α (PFT-α, on preimplantation porcine in vitro fertilized (IVF embryo development in culture. Treatment of PFT-α was administered at both early (0 to 48 hpi, and later stages (48 to 168 hpi of preimplantation development, and its impact upon the expression of five genes related to apoptosis (p53, bak, bcl-xL, p66Shc and caspase3, was assessed in resulting d 7 blastocysts, using real-time quantitative PCR. Total cell numbers, along with the number of apoptotic nuclei, as detected by the in situ cell death detection assay, were also calculated on d 7 in treated and non-treated control embryos. The results indicate that PFT-α, when administered at both early and later stages of porcine IVF embryo development, increases the incidence of apoptosis in resulting blastocysts. When administered at early cleavage stages, PFT-α treatment was shown to reduce the developmental competence of porcine IVF embryos, as well as reducing the quality of resulting blastocysts in terms of overall cell numbers. In contrast, at later stages, PFT-α administration resulted in marginally increased blastocyst development rates amongst treated embryos, but did not affect cell numbers. However, PFT-α treatment induced apoptosis and apoptotic related gene expression, in all treated embryos, irrespective of the timing of treatment. Our results indicate that PFT-α may severely compromise the developmental potential of porcine IVF embryos, and is a potent apoptotic agent when placed into porcine embryo culture media. Thus, caution should be exercised when using PFT-α as a specific inhibitor of p53 mediated apoptosis, in the context of porcine IVF embryo culture systems.

  4. EVALUATION OF ETHINYLESTRADIOL (EE2 EFFECT ON EMBRYO DEVELOPMENT IN COMMON CARP (CYPRINUS CARPIO

    Directory of Open Access Journals (Sweden)

    GABI DUMITRESCU

    2009-10-01

    Full Text Available Worldwide, the scientific researches performed during the last years are focused on the determination of the negative effects caused by natural and antropogeneous chemical compounds on aquatic species; these species are more exposed to most pollutants than the land species, for the simple reason that the aquatic environment is the last destination for most residues. Our research team proposed to test the toxic effect caused by ethinylestradiol on embryo development in common carp (Cyprinus carpio. Common carp embryos were purchased from the fish farm S.C. Acva Prod S.R.L. Cefa, Bihor County these were obtained by artificial reproduction. After taking and selection, the fecundated spawns were introduced in 10 Nunk culture plates of 45 ml, where we introduced 40 ml water, too. We created 3 batches, with two replications, namely: batch 1 – control, batch 2 – in water, we added ethinylestradiol (EE2 in concentration of 1.5 ng L-1 and batch 3 – we added in water a concentration of 7 ng L-1 EE2. During the incubation, the Nunk plates were kept in breeding aquariums, at a temperature of 24°C. Successive to the supervision of embryos in batch 3, 48 hours post-fecundation, we could observe evolution stagnations, 70% of them being in the stage of 40 somites of the segmentation period. At the same age, 100% of the control batch- embryos entered the stage of advanced faringula, and in batch 2 all embryos were in the stage of incipient faringula. 60-72 hours post-fecundation, all embryos in the batch 3 died, 90% in the 40 somite stage of the segmentation period and 10% in the stage of incipient faringula. 85 hours post-fecundation, all embryos belonging to the control batch were in the larva stage, while in batch 2, 90% were in the larva stage and 10% died in the stage of advanced faringula.

  5. Production of rhesus monkey cloned embryos expressing monomeric red fluorescent protein by interspecies somatic cell nuclear transfer

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Hai-Ying; Kang, Jin-Dan; Li, Suo; Jin, Jun-Xue; Hong, Yu; Jin, Long; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun, E-mail: yinxj33@msn.com

    2014-02-21

    Highlights: • Rhesus monkey cells were electroporated with a plasmid containing mRFP1, and an mRFP1-expressing cell line was generated. • For the first time, mRFP1-expressing rhesus monkey cells were used as donor cells for iSCNT. • The effect of VPA on the development of embryos cloned using iSCNT was determined. - Abstract: Interspecies somatic cell nuclear transfer (iSCNT) is a promising method to clone endangered animals from which oocytes are difficult to obtain. Monomeric red fluorescent protein 1 (mRFP1) is an excellent selection marker for transgenically modified cloned embryos during somatic cell nuclear transfer (SCNT). In this study, mRFP-expressing rhesus monkey cells or porcine cells were transferred into enucleated porcine oocytes to generate iSCNT and SCNT embryos, respectively. The development of these embryos was studied in vitro. The percentage of embryos that underwent cleavage did not significantly differ between iSCNT and SCNT embryos (P > 0.05; 71.53% vs. 80.30%). However, significantly fewer iSCNT embryos than SCNT embryos reached the blastocyst stage (2.04% vs. 10.19%, P < 0.05). Valproic acid was used in an attempt to increase the percentage of iSCNT embryos that developed to the blastocyst stage. However, the percentages of embryos that underwent cleavage and reached the blastocyst stage were similar between untreated iSCNT embryos and iSCNT embryos treated with 2 mM valproic acid for 24 h (72.12% vs. 70.83% and 2.67% vs. 2.35%, respectively). These data suggest that porcine-rhesus monkey interspecies embryos can be generated that efficiently express mRFP1. However, a significantly lower proportion of iSCNT embryos than SCNT embryos reach the blastocyst stage. Valproic acid does not increase the percentage of porcine-rhesus monkey iSCNT embryos that reach the blastocyst stage. The mechanisms underling nuclear reprogramming and epigenetic modifications in iSCNT need to be investigated further.

  6. DEVELOPMENTAL EXPOSURE OF FETAL OVARIES AND FETAL GERM CELLS TO ENDOMETRIOSIS CAUSES DIFFERENTIAL GENE EXPRESSION IN PRE-IMPLANTATION EMBRYOS OF FIRST AND SECOND GENERATION EMBRYOS OFFSPRING IN AN ENDOMETRIOSIS MODEL

    Science.gov (United States)

    Birt, Julie A.; Taylor, Kristen H.; Davis, J. Wade; Sharpe-Timms, Kathy L.

    2013-01-01

    Objective Characterize multigenerational gene expression anomalies in 8-cell stage embryos associated with developmental exposure to endometriosis. Design Using an endometriosis model in rats (F0 founder generation), evaluate gene expression in F1 (fetal exposure) and F2 (fetal germ cell exposure) generation 8-cell stage embryos. Setting Laboratory Animals Endometriosis model in rats (Endo) and controls (Sham) Interventions F0 Endo and Sham rats were bred. Half of the pregnant rats were euthanatized on gestational day 3 (F1 8-cell stage embryos); the others gestated to term (F1 females). Adult F1 females were bred and F2 8-cell embryos collected. Main outcome measures Maintenance of differential gene expression in F1 and F2 generation 8-cell embryos in endometriosis. Results Developmental exposure to endometriosis altered gene signaling pathways including apoptosis, cell cycle process, response to oxidative stress, negative regulation of molecular function and RNA processing. Apoptotic genes Diablo, Casp3, Parp1, Cad and Dnaja3 were increased, Nfkbia transcripts decreased in F1 Endo versus F1 Sham embryos. In F2 Endo versus Sham embryos, Casp3 and Cad were significantly increased plus Parp1 and Nfkbia tended to be elevated. Conclusions Fetal and germ cell exposure to endometriosis alters apoptotic gene expression in first and second generation 8-cell stage embryos, supporting the hypothesis of multigenerational inheritance from exposure to endometriosis in utero. PMID:23954358

  7. Embryo transfer day does not affect the initial maternal serum β-hCG levels: A retrospective cohort study.

    Science.gov (United States)

    Dahiya, Mona; Rupani, Karishma; Yu, Su Ling; Fook-Chong, Stephanie M C; Siew Fui, Diana Chia; Rajesh, Hemashree

    2017-05-01

    The aim of this study is to compare the serum β-hCG values post transfer of a cleavage stage embryo versus a blastocyst stage embryo at equal time intervals post oocyte retrieval (OR) in clinically pregnant patients, and to ascertain a β-hCG value to predict pregnancy outcomes. This is a retrospective cohort study of 560 women with clinical pregnancy who underwent an embryo transfer performed at either the cleavage stage or the blastocyst stage of embryo development between January 2003 and June 2014 at the Center for Assisted Reproduction (CARE), Singapore General Hospital. The serum β-hCG level was measured on day 17 post OR. The β-hCG values were not significantly different in the cleavage stage versus the blastocyst stage embryos (mean±SD: 387±486IU/L D3 vs. 352±268IU/L D5, p=0.96, median value 297 in both groups). Our study suggests that the initial maternal serum β-hCG values were not affected by the day of transfer of the embryos since assessing the β-hCG at equivalent points after transfer should not lead to a significant difference assuming the progress and development of the embryos occurred as expected. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Cucumber (Cucumis sativus L.) embryo development in situ after pollination with irradiated pollen

    International Nuclear Information System (INIS)

    Faris, N.M.; Niemirowicz-Szczytt, K.

    1999-01-01

    Embryological studies were undertaken to compare the normal development of cucumber endosperm and embryo with that observed after pollination with gamma-irradiated pollen (0.1 and 0.3 kGy). Delayed penetration of the pollen tube occurred at both irradiation doses. Endosperm and embryo development was also delayed, but was initiated within 6 days after pollination in 100% of embryo sacs at 0.1 kGy and in 70-80% at 0.3 kGy. Various abnormalities in endosperm and embryo cell structure confirmed progressive degeneration, which occurred earlier with the higher dose of irradiation. Degeneration increased dramatically; only 30-40% of the embryos reached the globular stage 15 days after pollination. (author)

  9. Tablet-based two-dimensional measurement for estimating the embryo area of brown rice

    Science.gov (United States)

    Intaravanne, Yuttana; Sumriddetchkajorn, Sarun; Chaitavon, Kosom; Chanhorm, Sataporn; Pongsoon, Prasit; Prasertsak, Anchalee

    2014-10-01

    The embryo or germ of a rice seed is growing to the shoot and the root parts of a seedling. In the early stage, the germinated embryo directly receives food from the endosperm. How healthy of the seedling can be physically predicted by measuring the areas of the embryo and endosperm. In this work, we show for the first time how the embryo and endosperm areas of a brown rice can be spatially measured. Our key design is based on the utilization of a tablet equipped with our lens module for capturing the rice seed image under white light illumination. Our Windows-based program is developed to analyze and separate the image of the whole brown rice into the embryo and endosperm parts within 2 seconds per seed. Our tablet-based system is just 30×30×6 cm3 with 1 kilogram in weight, capable to easily carry to perform in the field.

  10. TERATOGENIC EFFECTS OF TRANSPLACENTAL TRANSFUSION OF HETEROLOGOUS ANTISERA SIMULATED IN AN EXPERIMENTAL-MODEL USING INVITRO WHOLE RAT EMBRYO CULTURE

    NARCIS (Netherlands)

    VANDERZEE, DC; POELMANN, RE; ZWIERSTRA, RP; MENTINK, MMT; VERMEIJKEERS, C

    1991-01-01

    The effects of the transplacental transfusion of heterologous rabbit-anti-rat antiserum (RAR antiserum) and subsequent immunological interaction on the development of 9-10 days old rat embryos (stages 8-10 somites) were studied using an in vitro whole rat embryo culture. Transplacental transfusion

  11. Rotenone Decreases Hatching Success in Brine Shrimp Embryos by Blocking Development: Implications for Zooplankton Egg Banks.

    Directory of Open Access Journals (Sweden)

    Joseph A Covi

    Full Text Available While many zooplankton species recover quickly after the treatment of water resources with the piscicide, rotenone, some fail to reach pretreatment population density or, in rare cases, do not reappear at all. The variable impact of rotenone on zooplankton populations could stem from differences in the capacity of species to switch entirely to anaerobic catabolic pathways in the presence of rotenone, which blocks mitochondrial electron transport. Alternatively, variable responses among species could originate from differences in permeability of dormant life-stages to lipophilic chemicals like rotenone. The purpose of the present study was to determine the effects of rotenone on development, emergence and hatching of zooplankton embryos that lack both the anaerobic capacity to develop in the presence of rotenone and a permeability barrier to prevent the entry of rotenone during dormancy. Post-diapause embryos of the brine shrimp, Artemia franciscana, were employed as a model system, because they are permeable to lipophilic compounds when dechorionated and require aerobic conditions to support development. Early development in this species is also well characterized in the literature. Brine shrimp embryos were exposed to rotenone while development was either slowed by chilling or suspended by anoxia. Development, emergence and hatching were then observed in rotenone-free artificial seawater. The data presented demonstrate that rotenone freely diffuses across the embryonic cuticle in a matter of hours, and prevents development and emergence after brief exposures to ecologically relevant concentrations (0.025-0.5 mg L-1 of the piscicide. Neither the removal of rotenone from the environment, nor the removal of embryonic water with a hypertonic solution, are sufficient to reverse this block on development and emergence. These data indicate that rotenone could impair recruitment from egg banks for species of zooplankton that lack both an embryonic

  12. Book gill development in embryos and first and second instars of the horseshoe crab Limulus polyphemus L. (Chelicerata, Xiphosura).

    Science.gov (United States)

    Farley, Roger D

    2010-09-01

    The scanning electron microscope (SEM) was used to study the development of the opisthosomal appendages and book gills of the horseshoe crab, Limulus polyphemus. Later embryonic stages were examined as well as the first and second instars. The observations are compared with a much earlier light microscopic description of book gill development in the horseshoe crab and with book lung development in scorpion embryos and first and second instars in a recent study with SEM. After the third embryonic molt in the horseshoe crab, the opisthosomal appendages are of sufficient size so they could be fractured or dissected open so internal cells and other structures could be examined. The opisthosomal appendages and book gill lamellae of first and second instars were also opened. The observations support the earlier histological report that the gill lamellae are a hypodermal outgrowth from the posterior surface of the preceding branchial appendages. The genital operculum, branchial appendages and gill lamellae are very thin and consist of external cuticle, hypodermis and space holders. The latter help hold the cuticle walls in place so hemolymph can flow through the narrow channels. The space holders are formed from cell processes that extend into the lumen from the hypodermis just inside the external cuticle. In the recent SEM study in scorpion embryos and in some histological investigations in spider embryos, the book lung lamellae are formed by alignment of cells from an invaginated sac or mass of cells. This clearly differs from the mode of formation of gill lamellae as observed in this and earlier investigations. These reports of differences in embryology refine but do not preclude hypotheses about book gill/book lung homology since addition, deletion or modification of ancestral features often occur for the benefit of the embryos and larvae. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. EGF increases expression and activity of PAs in preimplantation rat embryos and their implantation rate

    Directory of Open Access Journals (Sweden)

    Har-Vardi Iris

    2007-01-01

    Full Text Available Abstract Background Embryo implantation plays a major role in embryogenesis and the outcome of pregnancy. Plasminogen activators (PAs have been implicated in mammalian fertilization, early stages of development and embryo implantation. As in-vitro developing embryos resulted in lower implantation rate than those developed in-vivo we assume that a reduced PAs activity may be involved. In the present work we studied the effect of EGF on PAs activity, quantity and embryo implantation. Methods Zygotes were flushed from rat oviducts on day one of pregnancy and grown in-vitro in R1ECM supplemented with EGF (10 ng/ml and were grown up to the blastocyst stage. The control groups were grown in the same medium without EGF. The distribution and quantity of the PAs were examined using fluorescence immunohistochemistry followed by measurement of PAs activity using the chromogenic assay. Implantation rate was studied using the embryo donation model. Results PAs distribution in the embryos was the same in EGF treated and untreated embryos. Both PAs were localized in the blastocysts' trophectoderm, supporting the assumption that PAs play a role in the implantation process in rats. EGF increased the quantity of uPA at all stages studied but the 8-cell stage as compared with controls. The tissue type PA (tPA content was unaffected except the 8-cell stage, which was increased. The activity of uPA increased gradually towards the blastocyst stage and more so due to the presence of EGF. The activity of tPA did not vary with the advancing developmental stages although it was also increased by EGF. The presence of EGF during the preimplantation development doubled the rate of implantation of the treated group as compared with controls.

  14. Effects of cryopreservation at various temperatures on the survival of kelp grouper (Epinephelus moara) embryos from fertilization with cryopreserved sperm.

    Science.gov (United States)

    Tian, Yongsheng; Chen, Zhangfan; Tang, Jiang; Duan, Huimin; Zhai, Jieming; Li, Bo; Ma, Wenhui; Liu, Jiangchun; Hou, Yunxia; Sun, Zhengxiang

    2017-04-01

    Fish embryo cryopreservation is highly important for the long-term preservation of genomic and genetic information; however, few successful cases of fish embryo cryopreservation have been reported over the past 60 years. This is the first study to use Epinephelus moara embryos from fertilization with cryopreserved sperm as experimental material. Embryos that developed to the 16-22 somite stage and tail-bud stage were treated with the vitrification solution PMG3T according to a five-step equilibration method and cryopreserved at various temperatures and storage duration. Only 19.9 ± 9.2% of 16-22 somite stage embryos and 1.3 ± 1.1% of tail-bud stage embryos survived when cooled at 4 °C for 60 min. In total, 8.0 ± 3.0% of 16-22 somite stage embryos survived when cooled at -25.7 °C for 30 min, 22.4 ± 4.7% of tail-bud stage embryos survived after 45 min of cooling at -25.7 °C, and none survived after 60 min. Only 2.0 ± 2.7% of embryos survived when cryopreserved at -140 °C for 20 min. However, 9.7% of tail-bud stage embryos survived after cryopreservation in liquid nitrogen (-196 °C) for 2 h. Most surviving embryos developed normally. Embryonic volume decreased and spherical segments appeared when embryos were treated with higher concentrations of vitrification solution. Additionally, the volume recovered gradually after rinsing with sucrose and seawater. This is the first estimate of the survival of E. moara embryos and larvae after cryopreservation. These findings provide a foundation for further explorations of fish embryo cryopreservation techniques. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. A Simple Method for Transportation of Mouse Embryos Using Microtubes and a Warm Box.

    Directory of Open Access Journals (Sweden)

    Mikiko Tokoro

    Full Text Available Generally, transportation of preimplantation embryos without freezing requires incubators that can maintain an optimal culture environment with a suitable gas phase, temperature, and humidity. Such incubators are expensive to transport. We reported previously that normal offspring were obtained when the gas phase and temperature could be maintained during transportation. However, that system used plastic dishes for embryo culture and is unsuitable for long-distance transport of live embryos. Here, we developed a simple low-cost embryo transportation system. Instead of plastic dishes, several types of microtubes-usually used for molecular analysis-were tested for embryo culture. When they were washed and attached to a gas-permeable film, the rate of embryo development from the 1-cell to blastocyst stage was more than 90%. The quality of these blastocysts and the rate of full-term development after embryo transfer to recipient female mice were similar to those of a dish-cultured control group. Next, we developed a small warm box powered by a battery instead of mains power, which could maintain an optimal temperature for embryo development during transport. When 1-cell embryos derived from BDF1, C57BL/6, C3H/He and ICR mouse strains were transported by a parcel-delivery service over 3 days using microtubes and the box, they developed to blastocysts with rates similar to controls. After the embryos had been transferred into recipient female mice, healthy offspring were obtained without any losses except for the C3H/He strain. Thus, transport of mouse embryos is possible using this very simple method, which might prove useful in the field of reproductive medicine.

  16. Aberrant epigenetic reprogramming of imprinted microRNA-127 and Rtl1 in cloned mouse embryos

    International Nuclear Information System (INIS)

    Cui Xiangshun; Zhang Dingxiao; Ko, Yoeung-Gyu; Kim, Nam-Hyung

    2009-01-01

    The microRNA (miRNA) genes mir-127 and mir-136 are located near two CpG islands in the imprinted mouse retrotransposon-like gene Rtl1, a key gene involved in placenta formation. These miRNAs appear to be involved in regulating the imprinting of Rtl1. To obtain insights into the epigenetic reprogramming of cloned embryos, we compared the expression levels of mir-127 and mir-136 in fertilized mouse embryos, parthenotes, androgenotes and cloned embryos developing in vitro. We also examined the DNA methylation status of the promoter regions of Rtl1 and mir-127 in these embryos. Our data showed that mir-127 and mir-136 were highly expressed in parthenotes, but rarely expressed in androgenotes. Interestingly, the expression levels of mir-127 and mir-136 in parthenotes were almost twice that seen in the fertilized embryos, but were much lower in the cloned embryos. The Rtl1 promoter region was hyper-methylated in blastocyst stage parthenotes (75.0%), moderately methylated (32.4%) in the fertilized embryos and methylated to a much lower extent (∼10%) in the cloned embryos. Conversely, the promoter region of mir-127 was hypo-methylated in parthenogenetically activated embryos (0.4%), moderately methylated (30.0%) in fertilized embryos and heavily methylated in cloned blastocysts (63-70%). These data support a role for mir-127 and mir-136 in the epigenetic reprogramming of the Rtl1 imprinting process. Analysis of the aberrant epigenetic reprogramming of mir-127 and Rtl1 in cloned embryos may help to explain the nuclear reprogramming procedures that occur in donor cells following somatic cell nuclear transfer (SCNT).

  17. Automated microinjection of recombinant BCL-X into mouse zygotes enhances embryo development.

    Directory of Open Access Journals (Sweden)

    Xinyu Liu

    Full Text Available Progression of fertilized mammalian oocytes through cleavage, blastocyst formation and implantation depends on successful implementation of the developmental program, which becomes established during oogenesis. The identification of ooplasmic factors, which are responsible for successful embryo development, is thus crucial in designing possible molecular therapies for infertility intervention. However, systematic evaluation of molecular targets has been hampered by the lack of techniques for efficient delivery of molecules into embryos. We have developed an automated robotic microinjection system for delivering cell impermeable compounds into preimplantation embryos with a high post-injection survival rate. In this paper, we report the performance of the system on microinjection of mouse embryos. Furthermore, using this system we provide the first evidence that recombinant BCL-XL (recBCL-XL protein is effective in preventing early embryo arrest imposed by suboptimal culture environment. We demonstrate that microinjection of recBCL-XL protein into early-stage embryos repairs mitochondrial bioenergetics, prevents reactive oxygen species (ROS accumulation, and enhances preimplantation embryo development. This approach may lead to a possible treatment option for patients with repeated in vitro fertilization (IVF failure due to poor embryo quality.

  18. Femtosecond laser surgery of two-cell mouse embryos: effect on viability, development, and tetraploidization

    Science.gov (United States)

    Osychenko, Alina A.; Zalessky, Alexandr D.; Kostrov, Andrey N.; Ryabova, Anastasia V.; Krivokharchenko, Alexander S.; Nadtochenko, Viktor A.

    2017-12-01

    The effect of the laser pulse energy and total expose of the energy incident on the embryo blastomere fusion probability was investigated. The probability of the four different events after laser pulse was determined: the fusion of two blastomeres with the following formation of tetraploid embryo, the destruction of the first blastomere occurs, the second blastomere conservation remains intact, the destruction and the death of both cells; two blastomeres were not fused, and no morphological changes occurred. We report on viability and quality of the embryo after laser surgery as a function of the laser energy incident. To characterize embryo quality, the probability of the blastocyst stage achievement was estimated and the blastocyst cells number was calculated. Blastocoel formation is the only event of morphogenesis in the preimplantation development of mammals, so we assumed it as an indicator of the time of embryonic "clocks" and observed it among fused and control embryos. The blastocoel formation time is the same for fused and control embryos. It indicates that embryo clocks were not affected due to blastomere fusion. Thus, the analysis of the fluorescence microscopic images of nuclei in the fused embryo revealed that nuclei fusion does not occur after blastomere fusion.

  19. Factors that affect the reproductive efficiency of the recipient within a bovine embryo transfer program

    Directory of Open Access Journals (Sweden)

    Arturo Duica A.

    2007-12-01

    Full Text Available The embryo transfer is a biotechnological technique that allows increasing the descendant of animals with high genetic value. The positive results, represented in pregnancy after the application of this technique, are affected by some factors that are inherent to the donor, the embryo, the technique, and the recipients which receive a strange embryo in the uterus allowing pregnancy. This review describes some factors affecting the reproductive efficiency of the recipients of bovine embryos within a program of embryo transfer. Its important to evaluate the parameters in this kind of recipients, as race, age, physiological status, health status, weight, reproductive tract integrity and management, and also too monitoring the ovarian structures while the estrus synchronization, and within previous and posterior stages in embryo transfer procedure. Therefore an optimum follicular development will be determinant to corpus luteum formation which generates enough serum progesterone concentrations to offer a right uterine environment allowing the optimum embryo development. Controlling the factors that affect the efficiency of the embryo transfer, it will obtain an increasing of positive results represented in pregnancies and births of individuals come from animals with high genetic value.

  20. Optimization of a novel nylon mesh container for human embryo ultrarapid vitrification.

    Science.gov (United States)

    Nakashima, Akira; Ino, Nao; Kusumi, Maki; Ohgi, Shirei; Ito, Megumu; Horikawa, Takashi; Nakagawa, Koji; Saito, Takakazu; Kamura, Toshiharu; Saito, Hidekazu

    2010-05-01

    To evaluate the efficacy of a nylon mesh container in vitrification of human embryos and to determine the optimal osmotic pressure of the initial thawing solution. Retrospective analysis. National Center for Child Health and Development, Tokyo, Japan. Infertile patients undergoing either in vitro fertilization or intracytoplasmic sperm injection in our hospital. Embryos, at the cleavage stage, were cryopreserved using the vitrification method in either a plastic straw or a nylon mesh container. The embryos were thawed using an initial osmotic pressure of either 0.5 M or 1.0 M sucrose with subsequent step-wise dilution. After thawing, the embryos were transferred to the uterus. Survival rate of blastomeres, embryo survival rate, implantation, and pregnancy rates, cancellation rate because of embryo damage. Use of nylon mesh and the 1.0 M sucrose thawing solution significantly improved blastomere survival rate (98.0 +/- 1.0%, mean +/- SEM), pregnancy rate (41.0%) and implantation rate (32.3%). Vitrification using a nylon mesh container and subsequent thawing in a 1.0 M sucrose solution is an easy and inexpensive method that improves the reliability of embryo cryopreservation of embryos without adverse effects on clinical outcomes. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Near-infrared laser irradiation improves the development of mouse pre-implantation embryos.

    Science.gov (United States)

    Yokoo, Masaki; Mori, Miho

    2017-05-27

    The aim of the present study was to assess the effects of near-infrared laser irradiation on the in vitro development of mouse embryos. Female ICR mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin (hCG), and mated with male mice. Two-cell stage embryos were collected 40 h after administering hCG and cultured in M16 medium. Two-cell embryos (0 h after culture), 8-cell embryos (approx. 30 h after culture), morula (approx. 48 h after culture), and blastocysts (approx. 73 h after culture) were irradiated at 904 nm for 60 s. These embryos were cultured in a time-lapse monitoring system and the timing of blastocyst hatching was evaluated. Some of the irradiated blastocysts were transferred to the uterine horns of pseudopregnant recipients immediately after irradiation. Pregnancy rates, and offspring growth and fertility, were evaluated. Near-infrared laser irradiation increased the speed of in vitro mouse embryo development. In irradiated blastocysts, hatching was faster than in control (non-irradiated) blastocysts (18.4 vs. 28.2 h, P embryo development in vitro, and increases the live birth rate without affecting the normality of the offspring. Thus, the near-infrared laser method may enhance the quality of embryos and contribute to improvements in reproductive technologies in mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Pregnancy outcome and live birth after IVF and ICSI according to embryo quality.

    Science.gov (United States)

    Fauque, Patricia; Léandri, Roger; Merlet, Françoise; Juillard, Jean-Claude; Epelboin, Sylvie; Guibert, Juliette; Jouannet, Pierre; Patrat, Catherine

    2007-05-01

    The pregnancy outcome and the chances of birth were assessed according to embryo quality after IVF or ICSI. The implantation rate (IR), the loss of gestational sacs rate (LGSR), and birth rate (BR) were determined according to the cleavage stage and the integrity of blastomeres after day-2 homogeneous embryo transfers (n = 1812). The LGSR was higher after transfers of 2-3-cell or 5-6-cell embryos and was significantly increased when more than 20% of the embryo volume was fragmented in 4-cell embryos. After transfers of 4-cell embryos without fragmentation, the BR was significantly higher than the BR after transfers of 4-cell embryos with 1-20% fragmentation (16.6% vs 13.1%). The difference was the consequence of a higher IR (20.4% vs 17.3%) but also of a lower LGSR (18.9% vs 24.2%). Not only implantation and the ability to give a pregnancy, but also the capacity to give a live birth are dependent on the embryo quality.

  3. Diseases of amphibian eggs and embryos

    Science.gov (United States)

    Green, D.E.; Converse, K.A.; Majumdar, S.K.; Huffman, J.E.; Brenner, F.J.; Panah, A.I.

    2005-01-01

    Amphibians generally are prolific egg producers. In tropical and semi-tropical regions, deposition of eggs may occur year-round or may coincide with rainy seasons, while in temperate regions, deposition of eggs usually occurs immediately after emergence from hibernation. Numbers of eggs produced by each species may vary from a few dozen to thousands. Accordingly, some eggs may be infertile and wastage of embryos is to be expected. Fertility, viability and decomposition of eggs and embryos must be considered before it is assumed that diseases are present. An important consideration in the evaluation of egg masses is the fact that some will contain infertile and non-viable eggs. These infertile and nonviable eggs will undergo decomposition and they may appear similar to eggs that are infected by a pathogen. Evaluation of egg masses and embryos for the presence of disease may require repeated observations in a given breeding season as well as continued monitoring of egg masses during their growth and development and over successive breeding seasons. Amphibian eggs rarely are subjected to a comprehensive health (diagnostic) examination; hence, there is scant literature on the diseases of this life stage. Indeed, the eggs of some North American amphibians have yet to be described. Much basic physiology and normal biomedical baseline data on amphibian eggs is lacking. For example, it is known that the aquatic eggs of some species of shrimp quickly are coated by a protective and commensal bacterium that effectively impedes invasion of the eggs by other environmental organisms and potential pathogens. In the absence of this bacterium, shrimp eggs are rapidly killed by other bacteria and fungi (Green, 2001). The possibility that amphibian eggs also have important symbiotic or commensal bacteria needs to be investigated. Furthermore, the quantity and types of chemicals in the normal gelatinous capsules of amphibian eggs have scarcely been examined. Abnormalities of the

  4. Effect of oxygen concentration on human embryo development evaluated by time-lapse monitoring

    DEFF Research Database (Denmark)

    Ingerslev, Hans Jakob; Hindkjær, Johnny Juhl; Kirkegaard, Kirstine

    2012-01-01

    -points for each cell division and blastocyst stages were registered until 120 hours after oocyte retrieval. Only 2PN embryos completing the first cleavage were evaluated. The groups were compared using one-way ANOVA or Kruskall-Wallis test. Estimates are reported as medians with 95% confidence intervals. Time......Introduction: Data from a number of studies indicate -but not unequivocally- that culture of embryos in 5% O2 compared to 20% O2 improves blastocyst formation in humans and various animal species and may yield better pregnancy rates in IVF. The detrimental effects of atmospheric oxygen were...... was to evaluate the influence of oxygen tension on human pre-implantation development using time-lapse monitoring. Materials and methods: Human embryos were cultured to the blastocyst stage in a time-lapse incubator (EmbryoScope™) in 20% O2 (group 1), 20% O2 for 24 hours followed by culture in 5% O2 (group 2...

  5. The Well-of-the-Well system: an efficient approach to improve embryo development.

    Science.gov (United States)

    Vajta, Gábor; Korösi, Tamás; Du, Yutao; Nakata, Kumiko; Ieda, Shoko; Kuwayama, Masashige; Nagy, Zsolt Peter

    2008-07-01

    Transfer of human embryos at the blastocyst stage may offer considerable benefits including an increased implantation rate and a decreased risk of multiple pregnancies; however, blastocyst culture requires an efficient and reliable in-vitro embryo culture system. In this study, the effect of the Well-of-the-Well (WOW) system consisting of microwells formed on the bottom of the culture dish was tested in three mammalian species, including humans. The WOW system resulted in significant improvement when comparing the drops for culture of in-vitro-matured and parthenogenetically activated porcine oocytes, and in-vivo-derived mouse zygotes. In human embryos, using a sibling oocyte design, embryos cultured in WOW developed to the blastocyst stage in a significantly higher proportion than did embryos cultured traditionally (55% in WOW and 37% in conventional culture; P WOW system or in microdrops. Transferable quality blastocyst development (48.9% of cultured zygotes) was observed in the WOW system. Ninety-four blastocysts transferred to 45 patients resulted in clinical pregnancy rates of 48.9%, including nine twin pregnancies, seven single pregnancies, five miscarriages and one ectopic pregnancy. The results indicate that the WOW system provides a promising alternative for microdrop culture of mammalian embryos, including human embryos.

  6. Effect of Calcium Chloride on the Permeation of the Cryoprotectant Dimethyl Sulfoxide to Japanese Whiting Sillago japonica Embryos

    Science.gov (United States)

    Rahman, Sk. Mustafizur; Majhi, Sullip Kumar; Suzuki, Toru; Strussmann, Carlos Augusto; Watanabe, Manabu

    Cryopreservation of fish eggs and embryos is a highly desired tool to promote aquaculture production and fisheries resource management, but it is still not technically feasible. The failure to develop successful cryopreservation protocols for fish embryos is largely attributed to poor cryoprotectant permeability. The purpose of this study was to test the effectiveness of CaCl2 to enhance cryoprotectant uptake by fish embryos. In this study, embryos (somites and tail elongation stages) of Japanese whiting Sillago japonica were exposed to 10 and 15% dimethyl sulfoxide (DMSO) in artificial sea water (ASW) or a solution of 0.125M CaCl2 in distilled water for 20 min at 24°C. The toxicity of all solutions was estimated from the hatching rates of the embryos and High Performance Liquid Chromatography was used to determine the amount of DMSO taken up during impregnation. The results showed that DMSO incorporation into the embryos was greatly (›50%) enhanced in the presence of CaCl2 compared to ASW. CaCl2 itself was not toxic to the embryos but, probably as a result of the enhanced DMSO uptake, caused decreases in survival of about 14-44% relative to ASW. Somites stage embryos were more tolerant than tail elongation ones to DMSO both as ASW and CaCl2 solutions. The use of CaCl2 as a vehicle for DMSO impregnation could be a promising aid for the successful cryopreservation of fish embryos.

  7. Nucleoli from two-cell embryos support the development of enucleolated germinal vesicle oocytes in the pig.

    Science.gov (United States)

    Kyogoku, Hirohisa; Ogushi, Sugako; Miyano, Takashi

    2012-11-01

    Recent research has shown that nucleoli of oocytes at the germinal vesicle (GV) stage (GV nucleoli) are not necessary for oocyte maturation but are essential for early embryonic development. Nucleoli of 2-cell embryos (2-cell nucleoli) have morphology similar to that of nucleoli in oocytes at the GV stage. In this study, we examined the ability of 2-cell nucleoli to substitute for GV nucleoli in terms of supporting early embryonic development by nucleolus aspiration (enucleolation) and transfer into metaphase II (MII) oocytes or 2-cell embryos that were derived from enucleolated oocytes at the GV stage in the pig. When 2-cell embryos were centrifuged to move the lipid droplets to one side of the blastomere, multiple nucleoli in the nucleus fused into a single nucleolus. The nucleoli were then aspirated from the 2-cell embryos by micromanipulation. The injection of 2-cell nucleoli to GV enucleolated oocytes at the MII stage rescued the embryos from the early embryonic arrest, and the resulting oocytes developed to blastocysts. However, the injection of 2-cell and GV nucleoli to 2-cell embryos derived from GV enucleolated oocytes rarely restored the development to blastocysts. These results indicate that 2-cell nucleoli support early embryonic development as GV nucleoli and that the presence of nucleoli is essential for pig embryos before the 2-cell stage.

  8. Growth and development of cultured carrot cells and embryos under spaceflight conditions

    Science.gov (United States)

    Krikorian, A. D.; Dutcher, F. R.; Quinn, C. E.; Steward, F. C.

    1981-01-01

    Morphogenetically competent proembryonic cells and well-developed somatic embryos of carrot at two levels of organization were exposed for 18.5 days to a hypogravity environment aboard the Soviet Biosatellite Cosmos 1129. It was confirmed that cultured totipotent cells of carrot can give rise to embryos with well-developed roots and minimally developed shoots. It was also shown that the space hypogravity environment could support the further growth of already-organized, later somatic embryonic stages and give rise to fully developed embryo-plantlets with roots and shoots.

  9. Electrophoresis-Based Proteomics to Study Development and Germination of Date Palm Zygotic Embryos.

    Science.gov (United States)

    Sghaier-Hammami, Besma; Drira, Noureddine; Bahloul, Mouna; Jorrín-Novo, Jesús V

    2017-01-01

    Proteomics has become an important and powerful tool in plant biology research. To establish a proteomic reference map of date palm zygotic embryos (ZE), we separated and identified proteins from zygotic embryos during different developmental and germination phases using one, two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. Proteins are extracted with trichloroacetic acid (TCA)/acetone-phenol and resolved by gel electrophoresis. Gel images are captured and analyzed by appropriate software and statistical packages. Quantitative or qualitative variable bands or spots are subjected to MS analysis in order to identify them and correlate differences in the protein profiles with the different stages of date palm zygotic embryo development, maturation, and germination.

  10. Proteomics of early zebrafish embryos

    Directory of Open Access Journals (Sweden)

    Heisenberg Carl-Philipp

    2006-01-01

    Full Text Available Abstract Background Zebrafish (D. rerio has become a powerful and widely used model system for the analysis of vertebrate embryogenesis and organ development. While genetic methods are readily available in zebrafish, protocols for two dimensional (2D gel electrophoresis and proteomics have yet to be developed. Results As a prerequisite to carry out proteomic experiments with early zebrafish embryos, we developed a method to efficiently remove the yolk from large batches of embryos. This method enabled high resolution 2D gel electrophoresis and improved Western blotting considerably. Here, we provide detailed protocols for proteomics in zebrafish from sample preparation to mass spectrometry (MS, including a comparison of databases for MS identification of zebrafish proteins. Conclusion The provided protocols for proteomic analysis of early embryos enable research to be taken in novel directions in embryogenesis.

  11. Progress towards initiation of somatic embryogenesis from differentiated tissues of radiata pine (Pinus radiata D. Don) using cotyledonary embryos

    DEFF Research Database (Denmark)

    Find, Jens Iver; Hargreaves, Cathy L.; Reeves, Catherine B.

    2014-01-01

    of dissected embryos and a modified Litvay medium, Glitz, was best. This combination gave the highest rate of initiation, and it was possible to initiate somatic embryogenesis (SE) from differentiated cells in the epicotyledonary region of postcotyledonary zygotic embryos from the two tested families...... with an average initiation rate of approximately 24% and 7% from stage five and six embryos, respectively. This is different from established initiation protocols of embryogenic cultures in radiata pine, which has traditionally been based on embryo rescue and continued proliferation of immature zygotic embryos....... A further implication of initiation of SE from excised post-cotyledonary embryos was that the period of initiation of embryogenic cultures was extended from 4 to 12 wk....

  12. Pine somatic embryogenesis using zygotic embryos as explants.

    Science.gov (United States)

    Pullman, Gerald S; Bucalo, Kylie

    2011-01-01

    Somatic embryogenesis (SE) has the potential to be the lowest-cost method to rapidly produce large numbers of high-value somatic seedlings with desired characteristics for plantation forestry. At least 24 of the 115-120 known Pinus species can undergo SE. Initiation for most species works best with immature megagametophytes as starting material, although a few pines can initiate SE cultures from isolated mature seed embryos. Successful initiation depends heavily on explant type, embryo developmental stage, and medium salt base. Most first reports of initiation used 2,4-D and BAP or a combination of cytokinins. More recent reports have optimized initiation for many Pinus spp., but still use mostly the combinations of auxin and cytokinins. Initiation can be stimulated with medium supplements including abscisic acid (ABA), brassinosteroids, ethylene inhibitors, gibberellin inhibitors, organic acids, putrescine, specific sugar types (maltose, galactose, D-chiro-inositol, and D-xylose), triacontanol, vitamins (B12, biotin, vitamin E, and folic acid), or manipulation of environmental factors including pH, water potential, cone cold storage, gelling agent concentration, and liquid medium. Embryo development and maturation usually occur best on medium containing ABA along with water potential reduction (with sugars and polyethylene glycol) or water availability reduction (with raised gelling agent increasing gel-strength). Activated carbon and maltose may also improve embryo maturation. The main issues holding SE technology back are related to the high cost of producing a somatic seedling, incurred from low initiation percentages for recalcitrant species, culture loss, and decline after initiation and poor embryo maturation resulting in no or poor germination. Although vast progress has been made in pine SE technology over the past 24 years, fundamental studies on seed and embryo physiology, biochemistry, and gene expression are still needed to help improve the technology

  13. Wnt signaling in the early sea urchin embryo.

    Science.gov (United States)

    Kumburegama, Shalika; Wikramanayake, Athula H

    2008-01-01

    Wnt signaling regulates a remarkably diverse array of cellular and developmental events during animal embryogenesis and homeostasis. The crucial role that Wnt signaling plays in regulating axial patterning in early embryos has been particularly striking. Recent work has highlighted the conserved role that canonical Wnt signaling plays in patterning the animal-vegetal (A-V) axis in sea urchin and sea anemone embryos. In sea urchin embryos, the canonical Wnt signaling pathway is selectively turned on in vegetal cells as early as the 16-cell stage embryo, and signaling through this pathway is required for activation of the endomesodermal gene regulatory network. Loss of nuclear beta-catenin signaling animalizes the sea urchin embryo and blocks pattern formation along the entire A-V axis. Nuclear entry of beta-catenin into vegetal cells is regulated cell autonomously by maternal information that is present at the vegetal pole of the unfertilized egg. Analysis of Dishevelled (Dsh) regulation along the A-V axis has revealed the presence of a cytoarchitectural domain at the vegetal pole of the unfertilized sea urchin egg. This vegetal cortical domain appears to be crucial for the localized activation of Dsh at the vegetal pole, but the precise mechanisms are unknown. The elucidation of how Dsh is selectively activated at the vegetal cortical domain is likely to provide important insight into how this enigmatic protein is regulated during canonical Wnt signaling. Additionally, this information will shed light on the origins of embryonic polarity during animal evolution. This chapter examines the roles played by the canonical Wnt signaling pathway in the specification and patterning of the A-V axis in the sea urchin. These studies have led to the identification of a novel role for canonical Wnt signaling in regulating protein stability, and continued studies of Wnt signaling in this model system are likely to reveal additional roles for this pathway in regulating early

  14. In situ ultra-high vacuum transmission electron microscopy studies of the transient oxidation stage of Cu and Cu alloy thin films.

    Science.gov (United States)

    Yang, Judith C; Zhou, Guangwen

    2012-11-01

    Because environmental stability is an essential property of most engineered materials, many theories exist to explain oxidation mechanisms. Yet, nearly all classical oxidation theories assume a uniform growing film, where structural changes were not considered because of the previous lack of experimental procedure to visualize this non-uniform growth in conditions that allowed for highly controlled surfaces and impurities. With the advent of vacuum technologies and advances in microcopy techniques, especially in situ, one can now see structural changes under controlled surface conditions. Here, we present a review of our systematic studies on the transient oxidation stages of a model metal system, Cu, and its alloys, Cu-Au and Cu-Ni, by in situ ultra-high vacuum transmission electron microscopy (UHV-TEM). The dependence of the oxidation behavior on the crystal orientation, oxygen pressure, temperature and alloying is attributed to the structures of the oxygen-chemisorbed layer, oxygen surface diffusion, surface energy and the interfacial strain energy. Heteroepitaxial concepts, developed to explain thin film formation on a dissimilar substrate material (e.g., Ge on Si), described well these initial oxidation stages. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Soluble CD146, an innovative and non-invasive biomarker of embryo selection for in vitro fertilization.

    Directory of Open Access Journals (Sweden)

    Sylvie Bouvier

    Full Text Available Although progress was made in in vitro fertilization (IVF techniques, the majority of embryos transferred fail to implant. Morphology embryo scoring is the standard procedure for most of IVF centres for choosing the best embryo, but remains limited since even the embryos classified as "top quality" may not implant. As it has been shown that i CD146 is involved in embryo implantation and ii membrane form is shed to generate soluble CD146 (sCD146, we propose that sCD146 in embryo supernatants may constitute a new biomarker of embryo selection. Immunocytochemical staining showed expression of CD146 in early embryo stages and sCD146 was detected by ELISA and Western-blot in embryo supernatants from D2. We retrospectively studied 126 couples who underwent IVF attempt. The embryo culture medium from each transferred embryo (n = 222 was collected for measurement of sCD146 by ELISA. Significantly higher sCD146 concentrations were present in embryo supernatants that did not implant (n = 185 as compared to those that successfully implanted (n = 37 (1310 +/- 1152 pg.mL-1 vs. 845+/- 1173 pg.mL-1, p = 0.024. Sensitivity analysis performed on single embryo transfers (n = 71 confirmed this association (p = 0.0054. The computed ROC curve established that the optimal sCD146 concentration for embryo implantation is under 1164 pg.mL-1 (sensitivity: 76%, specificity: 48%, PPV: 25% and NPV: 92%. Over this sCD146 threshold, the implantation rate was significantly lower (9% with sCD146 levels >1164 pg.ml-1 vs. 22% with sCD146 levels ≤ 1164 pg.mL-1, p = 0.01. Among the embryos preselected by morphologic scoring, sCD146 determination could allow a better selection of the embryo(s, thus improving the success of elective single embryo transfer. This study establishes the proof of concept for the use of sCD146 as a biomarker for IVF by excluding the embryo with the highest sCD146 level. A multicentre prospective study will now be necessary to further establish its use in

  16. A high-resolution analytical scanning transmission electron microscopy study of the early stages of spinodal decomposition in binary Fe–Cr

    Energy Technology Data Exchange (ETDEWEB)

    Westraadt, J.E., E-mail: johan.westraadt@nmmu.ac.za [Centre for High Resolution TEM, Nelson Mandela Metropolitan University, University Way, Port Elizabeth 6031 (South Africa); Olivier, E.J.; Neethling, J.H. [Centre for High Resolution TEM, Nelson Mandela Metropolitan University, University Way, Port Elizabeth 6031 (South Africa); Hedström, P.; Odqvist, J.; Xu, X. [Dept. Materials Science and Engineering, KTH Royal Institute of Technology, Brinellvägen 23, 10044 Stockholm (Sweden); Steuwer, A. [Nelson Mandela Metropolitan University, Gardham Av., Port Elizabeth 6031 (South Africa)

    2015-11-15

    Spinodal decomposition (SD) is an important phenomenon in materials science and engineering. For example, it is considered to be responsible for the 475 °C embrittlement of stainless steels comprising the bcc (ferrite) or bct (martensite) phases. Structural characterization of the evolving minute nano-scale concentration fluctuations during SD in the Fe–Cr system is, however, a notable challenge, and has mainly been considered accessible via atom probe tomography (APT) and small-angle neutron scattering. The standard tool for nanostructure characterization, viz. transmission electron microscopy (TEM), has only been successfully applied to late stages of SD when embrittlement is already severe. However, we here demonstrate that the structural evolution in the early stages of SD in binary Fe–Cr, and alloys based on the binary, are accessible via analytical scanning TEM. An Fe–36 wt% Cr alloy aged at 500 °C for 1, 10 and 100 h is investigated using an aberration-corrected microscope and it is found that highly coherent and interconnected Cr-rich regions develop. The wavelength of decomposition is rather insensitive to the sample thickness and it is quantified to 2, 3 and 6 nm after ageing for 1, 10 and 100 h, which is in reasonable agreement with prior APT analysis. The concentration amplitude is more sensitive to the sample thickness and acquisition parameters but the TEM analysis is in good agreement with APT analysis for the longest ageing time. These findings open up for combinatorial TEM studies where both local crystallography and chemistry is required. - Highlights: • STEM-EELS analysis was successfully applied to resolve early stage SD in Fe–Cr. • Compositional wavelength measured with STEM-EELS compares well to previous ATP studies. • Compositional amplitude measured with STEM-EELS is a function of experimental parameters. • STEM-EELS allows for combinatorial studies of SD using complementary techniques.

  17. Chromatin remodeling in mammalian embryos.

    Science.gov (United States)

    Cabot, Birgit; Cabot, Ryan A

    2018-03-01

    The mammalian embryo undergoes a dramatic amount of epigenetic remodeling during the first week of development. In this review, we discuss several epigenetic changes that happen over the course of cleavage development, focusing on covalent marks (e.g., histone methylation and acetylation) and non-covalent remodeling (chromatin remodeling via remodeling complexes; e.g., SWI/SNF-mediated chromatin remodeling). Comparisons are also drawn between remodeling events that occur in embryos from a variety of mammalian species. © 2018 Society for Reproduction and Fertility.

  18. Spin labeling study of membranes in wheat embryo axes. 1. Partitioning of doxyl stearates into the lipid domains

    NARCIS (Netherlands)

    Vishnyakova, E.; Ruuge, A.; Golovina, E.A.; Hoekstra, F.A.; Tikhonov, A.N.

    2000-01-01

    The interaction of lipid soluble spin labels with wheat embryo axes has been investigated to obtain insight into the structural organization of lipid domains in embryo cell membranes, using conventional electron paramagnetic resonance (EPR) and saturation transfer EPR (ST-EPR) spectroscopy. Stearic

  19. Stage I/sub E/ recovery of electron-irradiated pure silver and of its dilute alloys with cadmium and indium

    International Nuclear Information System (INIS)

    Rizk, R.; Vajda, P.; Maury, F.; Lucasson, A.; Lucasson, P.

    1977-01-01

    Irradiations of silver specimens with electrons in the energy range 0.4--1.7 MeV were performed at liquid-helium temperatures. A subthreshold phenomenon has been observed which is taking over below approx. 750 keV. After separation of this effect, we have studied the annealing spectra of pure silver and of AgCd (25 and 50 ppm Cd) and AgIn (15 and 50 ppm In) diluted alloys following irradiation with different doses of 1.7-MeV electrons and after irradiation doping. The stage I/sub E/ recovery has been analyzed in terms of the chemical reaction rate theory. The corresponding rate equations have been solved numerically, and and the following values for the capture radii of a silver self-interstitial atom by a Cd and an In impurity were obtained: r/sub Cd//sup Ag/ = 0.15r/sub v/, r/sub In//sup Ag/ = (0.05--0.10) r/sub v/, where r/sub v/ is its annihilation radius at a vacancy. The best fit was obtained with a value of E/sub m/ = 88 meV for the migration energy of a self-interstitial

  20. In vitro tagging of embryos with nanoparticles

    OpenAIRE

    Fynewever, Tricia L.; Agcaoili, Evelyn S.; Jacobson, John D.; Patton, William C.; Chan, Philip J.

    2006-01-01

    Purpose: To develop an in vitro method for tagging embryos and to compare the development of the embryos after nanoparticles injection versus externally-applied nanoparticles derived from either polystyrene or polyacrylonitrile.

  1. Transcriptomic analysis highlights epigenetic and transcriptional regulation during zygotic embryo development of Pinus pinaster.

    Science.gov (United States)

    de Vega-Bartol, José J; Simões, Marta; Lorenz, W Walter; Rodrigues, Andreia S; Alba, Rob; Dean, Jeffrey F D; Miguel, Célia M

    2013-08-30

    It is during embryogenesis that the plant body plan is established and the meristems responsible for all post-embryonic growth are specified. The molecular mechanisms governing conifer embryogenesis are still largely unknown. Their elucidation may contribute valuable information to clarify if the distinct features of embryo development in angiosperms and gymnosperms result from differential gene regulation. To address this issue, we have performed the first transcriptomic analysis of zygotic embryo development in a conifer species (Pinus pinaster) focusing our study in particular on regulatory genes playing important roles during plant embryo development, namely epigenetic regulators and transcription factors. Microarray analysis of P. pinaster zygotic embryogenesis was performed at five periods of embryo development from early developing to mature embryos. Our results show that most changes in transcript levels occurred in the first and the last embryo stage-to-stage transitions, namely early to pre-cotyledonary embryo and cotyledonary to mature embryo. An analysis of functional categories for genes that were differentially expressed through embryogenesis highlighted several epigenetic regulation mechanisms. While putative orthologs of transcripts associated with mechanisms that target transposable elements and repetitive sequences were strongly expressed in early embryogenesis, PRC2-mediated repression of genes seemed more relevant during late embryogenesis. On the other hand, functions related to sRNA pathways appeared differentially regulated across all stages of embryo development with a prevalence of miRNA functions in mid to late embryogenesis. Identification of putative transcription factor genes differentially regulated between consecutive embryo stages was strongly suggestive of the relevance of auxin responses and regulation of auxin carriers during early embryogenesis. Such responses could be involved in establishing embryo patterning. Later in

  2. SOMATIC EMBRYOGENESIS AND MORPHOANATOMY OF Ocotea porosa SOMATIC EMBRYOS

    Directory of Open Access Journals (Sweden)

    Luciana Luiza Pelegrini

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812343Ocotea porosa seeds have strong tegument dormancy, recalcitrant behavior, low and irregular germinationand that makes its natural propagation difficult. The aim of this study was to establish a protocol ofregeneration of Ocotea porosa from somatic embryogenesis. Immature embryonic axes were inoculatedon WPM culture medium supplemented with 2.4-D (200 μM combined or not with hydrolyzed casein orglutamine (0.5 or 1 g l-1, during 90 days. The repetitive embryogenesis was induced on medium with 2.4-D(22.62 μM combined with 2-iP (2.46 μM followed by transfer to culture medium with hydrolyzed caseinor glutamine (1 g l-1 during 90 days. The maturation of somatic embryos was tested in culture mediumcontaining NAA (0.5 μM and 2-iP (5; 10 and 20 μM. The highest percentage of somatic embryos induction(8.3% was observed in WPM culture medium containing 200 μM 2.4-D and 1 g L-1 hydrolyzed casein andthe development of somatic embryos occurred indirectly. Repetitive somatic embryogenesis was promotedin WPM medium containing hydrolyzed casein or glutamine. However, the culture medium containinghydrolyzed casein promoted the maintenance of embryogenic capacity for more than two years. Duringthe maturity phase, there was a low progression of globular embryos to cordiform and torpedo stages.The different ontogenetic stages of somatic embryos of Ocotea porosa were characterized by histologicalstudies.

  3. Pollination and embryo development in Brassica rapa L. in microgravity

    Science.gov (United States)

    Kuang, A.; Popova, A.; Xiao, Y.; Musgrave, M. E.

    2000-01-01

    Plant reproduction under spaceflight conditions has been problematic in the past. In order to determine what aspect of reproductive development is affected by microgravity, we studied pollination and embryo development in Brassica rapa L. during 16 d in microgravity on the space shuttle (STS-87). Brassica is self-incompatible and requires mechanical transfer of pollen. Short-duration access to microgravity during parabolic flights on the KC-135A aircraft was used initially to confirm that equal numbers of pollen grains could be collected and transferred in the absence of gravity. Brassica was grown in the Plant Growth Facility flight hardware as follows. Three chambers each contained six plants that were 13 d old at launch. As these plants flowered, thin colored tape was used to indicate the date of hand pollination, resulting in silique populations aged 8-15 d postpollination at the end of the 16-d mission. The remaining three chambers contained dry seeds that germinated on orbit to produce 14-d-old plants just beginning to flower at the time of landing. Pollen produced by these plants had comparable viability (93%) with that produced in the 2-d-delayed ground control. Matched-age siliques yielded embryos of equivalent developmental stage in the spaceflight and ground control treatments. Carbohydrate and protein storage reserves in the embryos, assessed by cytochemical localization, were also comparable. In the spaceflight material, growth and development by embryos rescued from siliques 15 d after pollination lagged behind the ground controls by 12 d; however, in the subsequent generation, no differences between the two treatments were found. The results demonstrate that while no stage of reproductive development in Brassica is absolutely dependent upon gravity, lower embryo quality may result following development in microgravity.

  4. Movement of the external ear in human embryo.

    Science.gov (United States)

    Kagurasho, Miho; Yamada, Shigehito; Uwabe, Chigako; Kose, Katsumi; Takakuwa, Tetsuya

    2012-02-01

    External ears, one of the major face components, show an interesting movement during craniofacial morphogenesis in human embryo. The present study was performed to see if movement of the external ears in a human embryo could be explained by differential growth. In all, 171 samples between Carnegie stage (CS) 17 and CS 23 were selected from MR image datasets of human embryos obtained from the Kyoto Collection of Human Embryos. The three-dimensional absolute position of 13 representative anatomical landmarks, including external and internal ears, from MRI data was traced to evaluate the movement between the different stages with identical magnification. Two different sets of reference axes were selected for evaluation and comparison of the movements. When the pituitary gland and the first cervical vertebra were selected as a reference axis, the 13 anatomical landmarks of the face spread out within the same region as the embryo enlarged and changed shape. The external ear did move mainly laterally, but not cranially. The distance between the external and internal ear stayed approximately constant. Three-dimensionally, the external ear located in the caudal ventral parts of the internal ear in CS 17, moved mainly laterally until CS 23. When surface landmarks eyes and mouth were selected as a reference axis, external ears moved from the caudal lateral ventral region to the position between eyes and mouth during development. The results indicate that movement of all anatomical landmarks, including external and internal ears, can be explained by differential growth. Also, when the external ear is recognized as one of the facial landmarks and having a relative position to other landmarks such as the eyes and mouth, the external ears seem to move cranially. © 2012 Kagurasho et al; licensee BioMed Central Ltd.

  5. SOMATIC EMBRYOGENESIS AND MORPHOANATOMY OF Ocotea porosa SOMATIC EMBRYOS

    Directory of Open Access Journals (Sweden)

    Luciana Luiza Pelegrini

    2013-01-01

    Full Text Available Ocotea porosa seeds have strong tegument dormancy, recalcitrant behavior, low and irregular germination and that makes its natural propagation difficult. The aim of this study was to establish a protocol of regeneration of Ocotea porosa from somatic embryogenesis. Immature embryonic axes were inoculated on WPM culture medium supplemented with 2.4-D (200 μM combined or not with hydrolyzed casein or glutamine (0.5 or 1 g l-1, during 90 days. The repetitive embryogenesis was induced on medium with 2.4-D (22.62 μM combined with 2-iP (2.46 μM followed by transfer to culture medium with hydrolyzed casein or glutamine (1 g l-1 during 90 days. The maturation of somatic embryos was tested in culture medium containing NAA (0.5 μM and 2-iP (5; 10 and 20 μM. The highest percentage of somatic embryos induction (8.3% was observed in WPM culture medium containing 200 μM 2.4-D and 1 g L-1 hydrolyzed casein and the development of somatic embryos occurred indirectly. Repetitive somatic embryogenesis was promoted in WPM medium containing hydrolyzed casein or glutamine. However, the culture medium containing hydrolyzed casein promoted the maintenance of embryogenic capacity for more than two years. During the maturity phase, there was a low progression of globular embryos to cordiform and torpedo stages. The different ontogenetic stages of somatic embryos of Ocotea porosa were characterized by histological studies.

  6. The recovery of ureaplasmas from bovine embryos following in vitro exposure and ten washes.

    Science.gov (United States)

    Britton, A P; Miller, R B; Ruhnke, H L; Johnson, W H

    1988-01-01

    Twenty-six unhatched embryos and ova were exposed to Ureaplasma diversum strain 2312 in vitro for 16 h and subsequently washed ten times. Fifteen of the embryos and their wash fluids were cultured for ureaplasmas. Of the remaining 11 embryos, six were incubated with rabbit anti-Ureaplasma immunoglobulin (RAI) and five were incubated with serum from naive rabbits(NRS), after which all were incubated with protein A gold and prepared for electron microscopy. On ultrastructural examination, ureaplasmas were observed on the outer surface of the zona pellucida of all 11 embryos. The ureaplasmas on the six embryos incubated with RAI were labeled with gold particles, while those on the five embryos incubated with NRS were not labeled. Ureaplasmas were recovered from all 15 of the cultured embryos and all of the first and second wash fluids as well as intermittently from the third, fourth, sixth, seventh, eighth and ninth wash but not fom the fifth or tenth wash. It was concluded that viable ureaplasmas adhered to the zona pellucida during in vitro exposure of bovine embryos and were not removed by ten washes.

  7. Electron and high-dose-rate brachytherapy boost in the conservative treatment of stage I-II breast cancer. First results of the randomized Budapest boost trial

    International Nuclear Information System (INIS)

    Polgar, C.; Fodor, J.; Orosz, Z.

    2002-01-01

    Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n=104) or no further radiotherapy (n=103). Boost treatments consisted of either 16 Gy electron irradiation (n=52) or 12-14.25 Gy HDR BT (n=52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrence was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs 84.9% (p=0.049), 76.6% vs 66.2% (p=0.044), and 90.4% vs. 82.1% (p=0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs 91.4%; p=0.74). On multivariate analysis, patient age <40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs 7.8%; p=0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p=0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p=0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age

  8. To delay or not to delay a frozen embryo transfer after a failed fresh embryo transfer attempt?

    Science.gov (United States)

    Santos-Ribeiro, Samuel; Siffain, Johannie; Polyzos, Nikolaos P; van de Vijver, Arne; van Landuyt, Lisbet; Stoop, Dominic; Tournaye, Herman; Blockeel, Christophe

    2016-05-01

    To evaluate if increasing the interval between a failed fresh embryo transfer and a subsequent frozen embryo transfer (FET) cycle has any effect on clinical pregnancy rates (CPRs). Retrospective cohort study. University-based tertiary referral center. Women who underwent at least one FET after ovarian stimulation for in vitro fertilization (IVF) and a failed fresh embryo transfer attempt from January 2010 to November 2014. We divided our sample according to the "timing" of the first FET (TF-FET), defined by the interval between oocyte retrieval and the FET cycle start date. The start of the FET was classified as either immediate (≤22 days after oocyte retrieval) or delayed (>22 days after oocyte retrieval). None. CPR after the first FET. A total of 1,183 FET cycles (performed in 1,087 women) were included in our study. No significant differences were found between the immediate and delayed FET groups regarding age, number of oocytes retrieved, number of good-quality embryos produced, embryo developmental stage at FET, and number of frozen embryos transferred. Most importantly, the CPRs of the first FET did not differ significantly according to the TF-FET (32.5% after immediate FET vs. 31.7% after delayed FET), even after adjusting for potential confounding with the use of multivariable logistic regression. FETs performed immediately after fresh IVF cycles had CPRs similar to those postponed to a later time. Therefore, deferring FETs may unnecessarily prolong time to pregnancy. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  9. Telomere-to-centromere ratio of bovine clones, embryos, gametes, fetal cells, and adult cells.

    Science.gov (United States)

    Meerdo, Lora N; Reed, William A; White, Kenneth L

    2005-01-01

    In 1997, Dolly, the first animal cloned from an adult cell, was born. It was announced in 1999 that Dolly might be aging faster than normal because her telomeres were shorter than age-matched control sheep. Telomeres, a repeated DNA sequence located at the ends of linear chromosomes, allow for base pair loss during DNA replication. Telomere shortening acts as a "mitotic clock," leading to replicative senescence. By using whole cell lysate and slot-blot analysis, we determined the telomere-to-centromere ratio (T/C) for bovine gametes, embryos, fetal tissues (brain, heart, lung, kidney, uterus, ovary, and skin), adult donor cells, and cloned embryos. Our data indicates a consistency in T/C among the various fetal tissues. The T/C of sperm is significantly lower than in oocytes. The T/C decreases from the oocyte to the 2-8-cell stage embryo, increases dramatically at the morula stage, and decreases at the blastocyst stage. Our data shows no significant difference in T/C between cloned embryos and in vitro fertilized (IVF) embryos, but there is a significant difference between cloned embryos and adult donor cells. In conclusion, the enucleated bovine oocyte has the ability to reestablish the telomere length of adult somatic cell donor nuclei.

  10. Improving embryo quality in assisted reproduction

    NARCIS (Netherlands)

    Mantikou, E.

    2013-01-01

    The goal of this thesis was to improve embryo quality in assisted reproductive technologies by gaining more insight into human preimplantation embryo development and by improving in vitro culture conditions. To do so, we investigated an intriguing feature of the human preimplantation embryo, i.e.

  11. Mechanistic dissection of plant embryo initiation

    NARCIS (Netherlands)

    Radoeva, T.M.

    2016-01-01

    Land plants can reproduce sexually by developing an embryo from a fertilized egg cell, the zygote. After fertilization, the zygote undergoes several rounds of controlled cell divisions to generate a mature embryo. However, embryo formation can also be induced in a variety of other cell types in

  12. The development of ovary in quail's embryo

    African Journals Online (AJOL)

    user

    2011-01-24

    Jan 24, 2011 ... The experiment was conducted to study the development of ovary in quails' embryos which were incubated for 4 to 17 days and incubated out for 1 day. The quails' embryos or gonads were cut out and. HE staining was carried out. The results showed that when embryo was hatched for 4 days, lots of.

  13. Mechanistic dissection of plant embryo initiation

    NARCIS (Netherlands)

    Radoeva, T.M.

    2016-01-01

    Land plants can reproduce sexually by developing an embryo from a fertilized egg cell, the zygote. After fertilization, the zygote undergoes several rounds of controlled cell divisions to generate a mature embryo. However, embryo formation can also be induced in a variety of other cell types in many

  14. Embryo adoption: Some further considerations

    Science.gov (United States)

    Patterson, Colin

    2015-01-01

    Recent discussions of embryo adoption have sought to make sense of the teaching of the Congregation for the Doctrine of the Faith (CDF) document Dignitas personae which appeared to provide a negative judgment on such a practice. This article aims to provide a personalist account of the process of fertilization and implantation that might serve as the basis for the negative judgment of the CDF document. In doing so, it relies upon the idea that a person, including an embryo, is not to be considered in isolation, but always in relation to God and to others. This approach extends the substantialist conceptualizations commonly employed in discussions of this issue. More generally, the article seeks to highlight the value of a personalist re-framing for an understanding of the moral questions surrounding the beginning of life. Lay summary: This article seeks to make sense of what appears to be a clear-cut rejection, set out in the Congregation for the Doctrine of the Faith (CDF) document Dignitas personae, of the proposal for women to “adopt” surplus frozen embryos. It draws upon more recently developed modes of philosophical/theological reasoning to argue that, in human procreation, both fertilization and implantation represent constitutive dimensions of divine creative activity and so must be protected from manipulative technological intervention. Since embryo adoption requires this kind of technology, it makes sense for the Church document not to approve it. PMID:25698841

  15. Evaluation of cell number and DNA content in mouse embryos cultivated with uranium

    International Nuclear Information System (INIS)

    Kundt, Mirian S.; Cabrini, Romulo L.

    2000-01-01

    The evaluation of the degree of development, the number of cells and the DNA content, were used to evaluate the embryotoxicity of uranium. Embryos at a one cell stage were cultured with uranyl nitrate hexahydrate (UN) at a final concentration of uranium (U) of 26, 52 and 104 μgU/ml. At 24 hs of culture, the embryos at the 2 cell stage, were put in new wells with the same concentrations of U as the previous day, until the end of the period of incubation at 72 hs. At 72 hs of culture, 87% of the original one cell embryos were at morula stage, and in those cultivated with uranium, the percentage decreased significantly to 77; 63.24 and 40.79% respectively for the different U concentrations. Those embryos that exhibited a normal morphology, were selected and fixed on slides. The number of cells per embryo was evaluated in Giemsa stained preparations. The DNA content was evaluated cytophotometrically in Feulgen stained nuclei. The number of cells decreased significantly from 20,3 ± 5.6 in the control to 19 ± 6; 14 ± 3 and 13.9 ± 5.6 for the different concentrations. All the embryos evaluated showed one easy recognizable polar body, which was used a haploid indicator (n). The content of DNA was measured in a total of 20 control embryos and 16 embryos cultivated with UN. In control embryos, 92,7% of the nuclei presented a normal ploidy from 2n to 4n, 2,9% nuclei were hypoploid and 4,4% were hyperploid. The percentage of hypoploid nuclei rose in a dose-dependent fashion to 3.45; 44.45 and 50.34% respectively for the embryos cultured at the different U concentrations. The results indicate that U is embryotoxic, that its effects are dose dependent at the concentrations used in this study and that even those embryos that show a normal morphology, can be genetically affected. We show that the model employed is extremely sensitive. It is possible to use the preimplantation embryos, as a model to test the effect of possibly mutagenic agents of the nuclear industry. (author)

  16. Synchrotron X-ray tomographic microscopy of fossil embryos.

    Science.gov (United States)

    Donoghue, Philip C J; Bengtson, Stefan; Dong, Xi-ping; Gostling, Neil J; Huldtgren, Therese; Cunningham, John A; Yin, Chongyu; Yue, Zhao; Peng, Fan; Stampanoni, Marco

    2006-08-10

    Fossilized embryos from the late Neoproterozoic and earliest Phanerozoic have caused much excitement because they preserve the earliest stages of embryology of animals that represent the initial diversification of metazoans. However, the potential of this material has not been fully realized because of reliance on traditional, non-destructive methods that allow analysis of exposed surfaces only, and destructive methods that preserve only a single two-dimensional view of the interior of the specimen. Here, we have applied synchrotron-radiation X-ray tomographic microscopy (SRXTM), obtaining complete three-dimensional recordings at submicrometre resolution. The embryos are preserved by early diagenetic impregnation and encrustation with calcium phosphate, and differences in X-ray attenuation provide information about the distribution of these two diagenetic phases. Three-dimensional visualization of blastomere arrangement and diagenetic cement in cleavage embryos resolves outstanding questions about their nature, including the identity of the columnar blastomeres. The anterior and posterior anatomy of embryos of the bilaterian worm-like Markuelia confirms its position as a scalidophoran, providing new insights into body-plan assembly among constituent phyla. The structure of the developing germ band in another bilaterian, Pseudooides, indicates a unique mode of germ-band development. SRXTM provides a method of non-invasive analysis that rivals the resolution achieved even by destructive methods, probing the very limits of fossilization and providing insight into embryology during the emergence of metazoan phyla.

  17. Proteomic analysis of zebrafish embryos exposed to simulated-microgravity

    Science.gov (United States)

    Hang, Xiaoming; Ma, Wenwen; Wang, Wei; Liu, Cong; Sun, Yeqing

    Microgravity can induce a serial of physiological and pathological changes in human body, such as cardiovascular functional disorder, bone loss, muscular atrophy and impaired immune system function, etc. In this research, we focus on the influence of microgravity to vertebrate embryo development. As a powerful model for studying vertebrate development, zebrafish embryos at 8 hpf (hour past fertilization) and 24 hpf were placed into a NASA developed bioreac-tor (RCCS) to simulate microgravity for 64 and 48 hours, respectively. The same number of control embryos from the same parents were placed in a tissue culture dish at the same temper-ature of 28° C. Each experiment was repeated 3 times and analyzed by two-dimensional (2-D) gel electrophoresis. Image analysis of silver stained 2-D gels revealed that 64 from total 292 protein spots showed quantitative and qualitative variations that were significantly (Pmuscle B. Other protein spots showed significant expression alteration will be identified successively and the corresponding genes expression will also be measured by Q-PCR method at different development stages. The data presented in this study illustrate that zebrafish embryo can be significantly induced by microgravity on the expression of proteins involved in bone and muscle formation. Key Words: Danio rerio; Simulated-microgravity; Proteomics

  18. Arabidopsis phosphatidylinositol-phospholipase C2 (PLC2) is required for female gametogenesis and embryo development.

    Science.gov (United States)

    Di Fino, Luciano M; D'Ambrosio, Juan Martín; Tejos, Ricardo; van Wijk, Ringo; Lamattina, Lorenzo; Munnik, Teun; Pagnussat, Gabriela C; Laxalt, Ana M

    2017-04-01

    AtPLC2 is an essential gene in Arabidopsis, since it is required for female gametogenesis and embryo development. AtPLC2 might play a role in cell division during embryo-sac development and early embryogenesis. Phosphoinositide-specific phospholipase C (PI-PLC) plays an important role in signal transduction during plant development and in the response to various biotic- and abiotic stresses. The Arabidopsis PI-PLC gene family is composed of nine members, named PLC1 to PLC9. Here, we report that PLC2 is involved in female gametophyte development and early embryogenesis. Using two Arabidopsis allelic T-DNA insertion lines with different phenotypic penetrations, we observed both female gametophytic defects and aberrant embryos. For the plc2-1 mutant (Ws background), no homozygous plants could be recovered in the offspring from self-pollinated plants. Nonetheless, plc2-1 hemizygous mutants are affected in female gametogenesis, showing embryo sacs arrested at early developmental stages. Allelic hemizygous plc2-2 mutant plants (Col-0 background) present reduced seed set and embryos arrested at the pre-globular stage with abnormal patterns of cell division. A low proportion (0.8%) of plc2-2 homozygous mutants was found to escape lethality and showed morphological defects and disrupted megagametogenesis. PLC2-promoter activity was observed during early megagametogenesis, and after fertilization in the embryo proper. Immunolocalization studies in early stage embryos revealed that PLC2 is restricted to the plasma membrane. Altogether, these results establish a role for PLC2 in both reproductive- and embryo development, presumably by controlling mitosis and/or the formation of cell-division planes.

  19. Embryo cell allocation patterns are not altered by biopsy but can be linked with further development.

    Science.gov (United States)

    Sepulveda-Rincon, L P; Islam, N; Marsters, P; Campbell, B K; Beaujean, N; Maalouf, W E

    2017-12-01

    It has been suggested that first embryo cleavage can be related with the embryonic-abembryonic axis at blastocyst stage in mice. Thus, cells of the 2-cell embryo might be already biased to form the inner cell mass or trophectoderm. This study was conducted to observe the possible effects of embryo biopsy on cell allocation patterns during embryo preimplantation in two different mouse strains and the effects of these patterns on further development. First, one blastomere of the 2-cell embryo was injected with a lipophilic tracer and cell allocation patterns were observed at blastocyst stage. Blastocysts were classified into orthogonal, deviant or random pattern. For the first experiment, embryos were biopsied at 8-cell stage and total cell counts (TCC) were annotated. Furthermore, non-biopsied blastocysts were transferred into foster mothers. Then, pups and their organs were weighed two weeks after birth. Random pattern was significantly recurrent (≈60%), against orthogonal (patterns among groups. These patterns were not affected by biopsy procedure. However, TCC on deviant embryos were reduced after biopsy. Moreover, no differences were found between patterns for implantation rates, litter size, live offspring and organ weights (lungs, liver, pancreas and spleen). However, deviant pups presented heavier hearts and orthogonal pups presented lighter kidneys among the group. In conclusion, these results suggest that single blastomere removal does not disturb cell allocation patterns during pre-implantation. Nonetheless, the results suggest that embryos following different cell allocation patterns present different coping mechanisms against in vitro manipulations and further development might be altered. © 2017 Society for Reproduction and Fertility.

  20. Evolution of the "fourth stage" of epidemiologic transition in people aged 80 years and over: population-based cohort study using electronic health records.

    Science.gov (United States)

    Hazra, Nisha C; Gulliford, Martin

    2017-05-12

    In the "fourth stage" of epidemiological transition, the distribution of non-communicable diseases is expected to shift to more advanced ages, but age-specific changes beyond 80 years of age have not been reported. This study aimed to evaluate demographic and health transitions in a population aged 80 years and over in the United Kingdom from 1990 to 2014, using primary care electronic health records. Epidemiological analysis of chronic morbidities and age-related impairments included a cohort of 299,495 participants, with stratified sampling by five-year age group up to 100 years and over. Cause-specific proportional hazards models were used to estimate hazard ratios for incidence rates over time. Between 1990 and 2014, nonagenarians and centenarians increased as a proportion of the over-80 population, as did the male-to-female ratio among individuals aged 80 to 95 years. A lower risk of coronary heart disease (HR 0.54, 95% confidence interval [CI]: 0.50-0.58), stroke (0.83, 0.76-0.90) and chronic obstructive pulmonary disease (0.59, 0.54-0.64) was observed among 80-84 year-olds in 2010-2014 compared to 1995-1999. By contrast, the risk of type II diabetes (2.18, 1.96-2.42), cancer (1.52, 1.43-1.61), dementia (2.94, 2.70-3.21), cognitive impairment (5.57, 5.01-6.20), and musculoskeletal pain (1.26, 1.21-1.32) was greater in 2010-2014 compared to 1995-1999. Redistribution of the over-80 population to older ages, and declining age-specific incidence of cardiovascular and respiratory diseases in over-80s, are consistent with the "fourth stage" of epidemiologic transition, but increases in diabetes, cancer, and age-related impairment show new emerging epidemiological patterns in the senior elderly.

  1. Use of cultured rat embryos to evaluate the teratogenic activity of serum: cadmium and cyclophosphamide. [Serum-based culture media for growing rat embryos is used to determine the teratogenicity of cadmium and cyclophosphamide

    Energy Technology Data Exchange (ETDEWEB)

    Klein, N. W.; Vogler, M. A.; Chatot, C. L.; Pierro, L. J.

    1979-01-01

    Head fold stage rat embryos were cultured for 48 hrs in vitro on serum taken at various intervals from rats that had been injected ip with either cadmium or cyclophosphamide. Their response was compared to that of embryos cultured for the same period on control serum to which these substances were added directly. One and 4 hr sera from cadmium injected rats (2.13 mg Cd/sup + +//kg) were lethal. Eight hr serum allowed survival but embryos were exencephalic and contained reduced amounts of protein and DNA. The response to direct cadmium was characteristically different and was related to dosage and the extent to which zero-time embryos had progressed through the head fold stage. At 1.6 ..mu..M, Cd/sup + +/-susceptible embryos were hemorrhagic but not exencephalic. One hr serum from rats given cyclophosphamide (180 mg/kg) was lethal. On 4 hr serum, embryos survived but were exencephalic and contained less protein and DNA than controls. Embryos were resistant to direct cyclophosphamide up to 800 ..mu..g per ml of medium. At this concentration, embryos appeared morphologically normal but contained reduced amounts of protein.

  2. Contrasting Storage Protein Synthesis and Messenger RNA Accumulation during Development of Zygotic and Somatic Embryos of Alfalfa (Medicago sativa L.) 1

    Science.gov (United States)

    Krochko, Joan E.; Pramanik, Saroj K.; Bewley, J. Derek

    1992-01-01

    During development on hormone-free media, somatic embryos pass through distinct morphological stages that superficially resemble those of zygotic embryo development (globular, heart, torpedo, cotyledonary stages). Despite these similarities, they differ from zygotic embryos in the extent of cotyledonary development and the patterns of synthesis and quantitative expression of seed-specific storage proteins (7S, 11S, and 2S proteins). Alfin (7S) is the first storage protein synthesized in developing zygotic embryos (stage IV). The 11S (medicagin) and 2S (Low Molecular Weight, LMW) storage proteins are not detectable until the following stage of development (stage V), although all three are present before the completion of embryo enlargement. Likewise, the 7S storage protein is the first to be synthesized in developing somatic embryos (day 5). Medicagin is evident by day 7 and the LMW protein by day 10. In contrast to zygotic embryos, alfin remains the predominant storage protein in somatic embryos throughout development. Not only are the relative amounts of medicagin and the LMW protein reduced in somatic embryos but the LMW protein is accumulated much later than the other proteins. Quantification of the storage protein mRNAs (7S, 11S, and 2S) by northern blot analysis confirms that there are substantial differences in the patterns of message accumulation in zygotic and somatic embryos of alfalfa (Medicago sativa). In zygotic embryos, the 7S, 11S, and 2S storage protein mRNAs are abundant during maturation and, in particular, during the stages of maximum protein synthesis (alfin, stages VI and VII; medicagin, stage VII; LMW, stage VII). In somatic embryos, the predominance of the 7S storage protein is correlated with increased accumulation of its mRNA, whereas the limited synthesis of the 11S storage protein is associated with much lower steady-state levels of its message. The mRNA for the LMW protein is present already by 3 days after transfer to hormone-free media

  3. The contractility of elongated microvilli in early sea urchin embryos.

    Science.gov (United States)

    Spiegel, Evelyn; Howard, Louisa; Spiegel, Melvin

    1990-04-01

    Elongated microvilli attach the early sea urchin embryo to the fertilization envelope and support it in a concentric position within the perivitelline space. The contractility of the elongated microvilli was demonstrated in several ways. (1) During normal cleavage, these microvilli change their length to adapt to the change in shape and numbers of blastomeres. (2) When treated with calcium-free sea water, embryos become eccentrically located and the microvilli extend further than normal on one side; when returned to normal sea water, the embryos become centered again. (3) Several agents cause the fertilization envelope to become higher and thinner than normal and the elongated microvilli to extend correspondingly if treated within ten min after fertilization. In some cases, both elongated microvilli and fertilization envelope return to normal size when returned to normal sea water. (4) Fertilization in a papain solution causes the elongated microvilli and the fertilization envelope to contract to the surface of the embryo. (5) Refertilization after the papain-induced contraction can bring about the elongation of these microvilli and the elevation of the fertilization envelope a second time. It was also shown that elongated microvilli are extended immediately upon fertilization, at the same time as the short microvilli. The firm adherence of the tips of elongated microvilli to the fertilization envelope by means of extracellular matrix fibers is shown in a high voltage electron microscope stereoimage. This allows us to understand why it is that when the elongated microvilli extend or contract, the fertilization envelope also extends and contracts accordingly.

  4. Global gene expression profiling of individual human oocytes and embryos demonstrates heterogeneity in early development.

    Directory of Open Access Journals (Sweden)

    Lisa Shaw

    Full Text Available Early development in humans is characterised by low and variable embryonic viability, reflected in low fecundity and high rates of miscarriage, relative to other mammals. Data from assisted reproduction programmes provides additional evidence that this is largely mediated at the level of embryonic competence and is highly heterogeneous among embryos. Understanding the basis of this heterogeneity has important implications in a number of areas including: the regulation of early human development, disorders of pregnancy, assisted reproduction programmes, the long term health of children which may be programmed in early development, and the molecular basis of pluripotency in human stem cell populations. We have therefore investigated global gene expression profiles using polyAPCR amplification and microarray technology applied to individual human oocytes and 4-cell and blastocyst stage embryos. In order to explore the basis of any variability in detail, each developmental stage is replicated in triplicate. Our data show that although transcript profiles are highly stage-specific, within each stage they are relatively variable. We describe expression of a number of gene families and pathways including apoptosis, cell cycle and amino acid metabolism, which are variably expressed and may be reflective of embryonic developmental competence. Overall, our data suggest that heterogeneity in human embryo developmental competence is reflected in global transcript profiles, and that the vast majority of existing human embryo gene expression data based on pooled oocytes and embryos need to be reinterpreted.

  5. Toxicity of cypermethrin and deltamethrin insecticides on embryos and larvae of Physalaemus gracilis (Anura: Leptodactylidae).

    Science.gov (United States)

    Macagnan, Natani; Rutkoski, Camila F; Kolcenti, Cassiane; Vanzetto, Guilherme V; Macagnan, Luan P; Sturza, Paola F; Hartmann, Paulo A; Hartmann, Marilia T

    2017-09-01

    It is important to establish the toxicity pesticides against non-target species, especially those pesticides used in commercial formulations. Pyrethroid insecticides are widely used in agriculture despite their toxicity to aquatic animals. In this study, we determine the toxicity of commercial formulation of two pyrethroid insecticides, cypermethrin and deltamethrin, in two life stages of Physalaemus gracilis, a frog that breeds in agricultural ecosystems and has potential contact with pyrethroid pesticides. The acute toxicity test (96 h) was carried out with embryos of stage 17:18 and larvae of stages 24:25. Embryos were more resistant to both pesticides than larvae. In embryo mobility assays, we found that both pesticides caused spasmodic contractions, suggestive of neurological effects. In acute toxicity assays, we found that P. gracilis is more resistant to these insecticides than other studied species.

  6. Tritiated thymidine radiotoxicity in mice embryos in preimplantation phase, culture and in vitro fertilization

    International Nuclear Information System (INIS)

    Kikuchi, O.K.; Ohyama, H.; Yamamada, T.

    1992-01-01

    Mouse embryos have been used as a good biological system to study the effects of ionizing radiation on proliferating cells and on the mammal embryos development. In vitro fertilization is an ideal technique for irradiating or labelling many zygotes at the same developmental stage and with the the same developmental stage and with the security that it will not have any influence of maternal organism. In the present work different concentrations of methyl- 3 H-thymidine was added to the culture medium micro drops containing the zygotes at pro nuclear stage and the embryos were cultured in vitro at 37 0 C in a humidified atmosphere with 5% of CO 2 for four days up established end point to calculate the LD 50 , the 50% lethal dose. (author)

  7. Children born after cryopreservation of embryos or oocytes: a systematic review of outcome data

    DEFF Research Database (Denmark)

    Wennerholm, U-B; Söderström-Anttila, V; Bergh, C

    2009-01-01

    BACKGROUND: An estimated 3.5 million children have been born to date using assisted reproduction technologies. We reviewed the data in order to evaluate current knowledge of medical outcome for IVF/ICSI children born after cryopreservation, slow freezing and vitrification of early cleavage stage...... of blastocysts and for vitrification of early cleavage stage embryos, blastocysts and oocytes, limited neonatal data was reported. We found no long-term child follow-up data for any cryopreservation technique. CONCLUSION: Data concerning infant outcome after slow freezing of embryos was reassuring. Properly...... controlled follow-up studies of neonatal outcome are needed after slow freezing of blastocysts and after vitrification of early cleavage stage embryos, blastocysts and oocytes. In addition, child long-term follow-up studies for all cryopreservation techniques are essential....

  8. MORPHOLOGICAL CHANGES DURING THE DEVELOPMENT OF SOMATIC EMBRYOS OF SAGO (Metroxylon sagu Rottb.

    Directory of Open Access Journals (Sweden)

    Pauline D. Kasi

    2016-10-01

    Full Text Available Development of somatic embryos of sago (Metroxylon sagu Rottb. on agar-solidified medium are highly varied producing heterogeneous seedlings. Understanding of this phenomenon may help in improving the cultural procedures and conditions of sagosomatic embryogenesis to obtain uniform seedlings in a large scale. This experiment was conducted at the laboratory for plant cell culture and micropropagation, Indonesian Biotechnology Research Institute for Estate Crops from January to March 2006 to examine morphological changes i.e. color and development stages of sago during their somatic embryo development on an agar-solidified medium. Twenty single globular somatic embryos of sago with specific color (yellowish, greenish, and reddish were cultured in a Petri dish supplemented with a solid medium. The medium was a micronutrients-modified MS (MMS with half strength of macronutrients containing 0.01 mg l-1 ABA, 2 mg l-1 kinetin, 20 g l-1 sucrose, 0.5 g l-1 activated charcoal, and 2 g l-1 gelrite. Parameter observed was the percentage of embryo’s number based on color and developmental stage. The result showed that at the end of 6-week culture passage, most originally greenish (80.8% and reddish (95.8% embryos remained unchanged in their colors, whereas almost half of the originally yellowish embryos turned to greenish and only 30%remained yellowish. At the same time, single globular embryos have changed gradually into the next developmental stages, although not all of the embryos were germinated. The initial color of embryo affected the rate of the developmental stage changes. Yellowish and greenish globular embryos developed more rapidly into cotyledon or germinant stages at 58% and 55% respectively, in 6 weeks than the reddish ones (41%. Therefore, the yellowish and greenish embryos are the best sources of material for in vitro mass propagation and synthetic seed production of sago.

  9. [Moral dignity at the beginning of life. The embryo as a marginal being].

    Science.gov (United States)

    Rehmann-Sutter, Christoph

    2008-08-01

    Ethical questions in relation to human embryos in vitro are today raised by reproductive medicine, preimplantation genetic diagnosis and stem cell research. Various discourses--biological, political and medical--describe the embryo from different perspectives. Empirical investigations of the perceptions and concerns of patients in IVF treatments provide important insights. Referring to a variety of discourses and perspectives, the paper develops an ethical analysis of the responsibility for embryos in vitro, with a special emphasis on the relationships involved. In the context of current discussions about the moral status of the embryo, the paper differentiates between four different meanings of "potentiality" of the embryo: (a) external potentiality, (b) the tendency towards a developmental pathway, (c) the transitive determination by a program, (d) preformation. For different reasons, (a), (c) and (d) are rejected. On the basis of potentiality in the sense of (b), the embryo can be described as a developmental being that gives its developmental potential continuously to the next stage ("self-transcendence") and is on the way of becoming a human. This is a reason for defending ethical responsibility for human embryos as the moral recognition of a growing dignity that becomes more intense with increasing proximity to birth.

  10. Germination of somatic embryos of Swietenia macrophylla in semisolid culture media

    Directory of Open Access Journals (Sweden)

    Raúl Collado

    2005-01-01

    Full Text Available With the objective to establish a suitable culture medium and to determine the optimum culture time for the germination of somatic embryos of Swietenia macrophylla King, it was carried out these work. Somatic embryos at the cotyledonal stage were placed in a culture medium formed by the half of the MS salts for their germination . three concentrations of 6-BAP (0.2, 0.4 and 0.6 mg.l-1, two concentrations of AG (1.0 and 2.0 mg.l-1 and a culture medium control without growth regulators were studied. In the culture medium wher3e the best results were obtained, the effect of the culture time on the germination of somatic embryos (30, 60 and 90 days of culture was studied. The major number of somatic embryos with total germination was obtained in the culture medium without growth regulators, with significant differences to the rest of the treatments. The highest value of somatic embryos with secondary embryogenesis was presented when 0.6 mg.l-1 of 6-BAP were added to the culture medium. The increase of the culture time to 60 and 90 days increased significantly the total germination of the somatic embryos. These results allowed to define a culture medium for the germination of somatic embryos of Swietenia macrophylla King composed by the half of the MS salts without growth regulators with a culture time of 60 days. Key words: in vitro culture, Mahogany, regeneration, somatic embryogenesis

  11. The method of rodent whole embryo culture using the rotator-type bottle culture system.

    Science.gov (United States)

    Takahashi, Masanori; Osumi, Noriko

    2010-08-28

    Whole embryo culture (WEC) technique has been developed in 1950's by New and his colleagues, and applied for developmental biology (1). Although development and growth of mammalian embryos are critically dependent on the function of the placenta, WEC technique allows us to culture mouse and rat embryos ex vivo condition during limited periods corresponding to midgestation stages during embryonic day (E) 6.5-E12.5 in the mouse or E8.5-E14.5 in the rat (2, 3, 4). In WEC, we can directly target desired areas of embryos using fine glass capillaries because embryos can be manipulated under the microscope. Therefore, rodent WEC is very useful technique when we want to study dynamic developmental processes of postimplanted mammalian embryos. Up to date, several types of WEC systems have been developed (1). Among those, the rotator-type bottle culture system is most popular and suitable for long-term culture of embryos at midgestation, i.e., after E9.5 and E11.5 in the mouse and rat, respectively (1). In this video protocol, we demonstrate our standard procedures of rat WEC after E12.5 using a refined model of the original rotator system, which was designed by New and Cockroft (5, 6), and introduce various applications of WEC technique for studies in mammalian developmental biology.

  12. Regulation of the maize (Zea mays L.) embryo proteome by RTCS which controls seminal root initiation.

    Science.gov (United States)

    Muthreich, Nils; Schützenmeister, André; Schütz, Wolfgang; Madlung, Johannes; Krug, Karsten; Nordheim, Alfred; Piepho, Hans-Peter; Hochholdinger, Frank

    2010-01-01

    Seminal roots are initiated at the scutellar node during maize (Zea mays L.) embryo development. The maize mutant rtcs (rootless concerning crown and seminal roots) does not initiate seminal roots while its wild-type siblings form on average 2.9 seminal roots per seedling. In this study, proteome profiles of 25-day-old immature maize embryos were compared between wild-type and rtcs plants via two-dimensional electrophoresis (2-DE). Electrospray ionization tandem mass spectrometry (ESI-MS/MS) identified 23 proteins encoded by 21 different genes that were differentially accumulated between wild-type and rtcs embryos (Fc> or =2; FDRenergetics in plants. Comparison of embryonic proteins differentially accumulated between wild-type and rtcs embryos revealed little overlap with proteins differentially accumulated between wild-type and rum1 embryos which also do not initiate seminal roots. This might be due to distinct influences of RTCS and RUM1 on the composition of the embryo proteome, but could also be explained by different stages of embryo development that were analyzed in these studies. Copyright 2009 Elsevier GmbH. All rights reserved.

  13. Reptile Embryos Lack the Opportunity to Thermoregulate by Moving within the Egg.

    Science.gov (United States)

    Telemeco, Rory S; Gangloff, Eric J; Cordero, Gerardo A; Mitchell, Timothy S; Bodensteiner, Brooke L; Holden, Kaitlyn G; Mitchell, Sarah M; Polich, Rebecca L; Janzen, Fredric J

    2016-07-01

    Historically, egg-bound reptile embryos were thought to passively thermoconform to the nest environment. However, recent observations of thermal taxis by embryos of multiple reptile species have led to the widely discussed hypothesis that embryos behaviorally thermoregulate. Because temperature affects development, such thermoregulation could allow embryos to control their fate far more than historically assumed. We assessed the opportunity for embryos to behaviorally thermoregulate in nature by examining thermal gradients within natural nests and eggs of the common snapping turtle (Chelydra serpentina; which displays embryonic thermal taxis) and by simulating thermal gradients within nests across a range of nest depths, egg sizes, and soil types. We observed little spatial thermal variation within nests, and thermal gradients were poorly transferred to eggs. Furthermore, thermal gradients sufficiently large and constant for behavioral thermoregulation were not predicted to occur in our simulations. Gradients of biologically relevant magnitude have limited global occurrence and reverse direction twice daily when they do exist, which is substantially faster than embryos can shift position within the egg. Our results imply that reptile embryos will rarely, if ever, have the opportunity to behaviorally thermoregulate by moving within the egg. We suggest that embryonic thermal taxis instead represents a play behavior, which may be adaptive or selectively neutral, and results from the mechanisms for behavioral thermoregulation in free-living stages coming online prior to hatching.

  14. Individual demands of human embryos on IVF culture medium: influence on blastocyst development and pregnancy outcome.

    Science.gov (United States)

    Wirleitner, B; Vanderzwalmen, P; Stecher, A; Zech, M H; Zintz, M; Zech, N H

    2010-12-01

    The elucidation of the metabolic requirements of human embryos in vivo or in vitro remains, despite being intensively investigated, a work in progress. The adoption of extended embryo culture to the blastocyst stage during the last decade has entailed new challenges. With the increased attention to culture media formulations, more evidence on the sensitivity of embryos to their early environmental conditions is accumulating which might affect phenotype and developmental potential. A retrospective study was conducted that comprised 286 IVF cycles to evaluate the effect of two different culture media on blastocyst development and pregnancy outcome. Embryos were either cultured in a one step or a sequential medium. Higher fertilization rates and augmented blastocyst rates as well as higher implantation rates were observed when embryos were cultured in one step medium (Pcultured in either medium resulted in a significantly higher rate of twin pregnancies. Although multiple pregnancies should be avoided in assisted reproduction treatment to reduce risks for offspring and mother, this higher frequency of twin pregnancies resulting from the transfer of embryos derived from different culture media suggests that each embryo makes individual demands on its early environment. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  15. Chromosomal mosaicism in mouse two-cell embryos after paternal exposure to acrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, Francesco; Bishop, Jack; Lowe, Xiu; Wyrobek, Andrew J

    2008-10-14

    Chromosomal mosaicism in human preimplantation embryos is a common cause ofspontaneous abortions, however, our knowledge of its etiology is limited. We used multicolor fluorescence in situ hybridization (FISH) painting to investigate whether paternally-transmitted chromosomal aberrations result in mosaicism in mouse 2-cell embryos. Paternal exposure to acrylamide, an important industrial chemical also found in tobacco smoke and generated during the cooking process of starchy foods, produced significant increases in chromosomally defective 2-cell embryos, however, the effects were transient primarily affecting the postmeiotic stages of spermatogenesis. Comparisons with our previous study of zygotes demonstrated similar frequencies of chromosomally abnormal zygotes and 2-cell embryos suggesting that there was no apparent selection against numerical or structural chromosomal aberrations. However, the majority of affected 2-cell embryos were mosaics showing different chromosomal abnormalities in the two blastomeric metaphases. Analyses of chromosomal aberrations in zygotes and 2-cell embryos showed a tendency for loss of acentric fragments during the first mitotic division ofembryogenesis, while both dicentrics and translocations apparently underwent propersegregation. These results suggest that embryonic development can proceed up to the end of the second cell cycle of development in the presence of abnormal paternal chromosomes and that even dicentrics can persist through cell division. The high incidence of chromosomally mosaic 2-cell embryos suggests that the first mitotic division of embryogenesis is prone to missegregation errors and that paternally-transmitted chromosomal abnromalities increase the risk of missegregation leading to embryonic mosaicism.

  16. The development al potential of the embryos of wolf spider Xerolycosa nemoralis from areas variously burdened with metals

    Directory of Open Access Journals (Sweden)

    Babczyńska A.

    2013-04-01

    Full Text Available The aim of this study was to assess and describe the developmental potential of the embryos of the wolf spider X. nemoralis collected from the reference site (Pilica and a site heavily polluted with metals (Welnowiec (southern Poland. For the analyses of the progress of development the embryos the computer microtomography was used. Adenylate concentration was measured using luminometric method. The macroscopic observations of the development of individual embryos revealed significant differences in the duration of embryogenesis (14,5 ±0.5 days in Pilica vs 16.5±0.53 in Welnowiec. The computer microtomography analyses enabled us to describe the geometry of the eggs inside the cocoon as well as to see the morphology of embryos inside the cocoon and to recognize selected developmental stages of the embryos. The concentration of cadmium in embryos in Welnowiec was significantly lower than in the embryos from the reference site, while the concentration of copper in the embryos from Pilica was significantly, 4 times lower than in Wełnowiec. The energy status indices (ATP concentration and ADP/ATP ratio did not differ significantly in the embryos from the two sites.

  17. The zebrafish digital embryo: in toto reconstruction of zebrafish early embryonic development with digital scanned laser light sheet fluorescence microscopy

    Science.gov (United States)

    Keller, Philipp J.; Schmidt, Annette D.; Wittbrodt, Joachim; Stelzer, Ernst H. K.

    2009-07-01

    The analysis of all cell movements and all cell interactions in a vertebrate during the entire period of embryonic development is a fundamental goal in biology. Using DSLM, we recorded the development of entire zebrafish embryos in vivo and with sub-cellular resolution. By imaging at a speed of 1.5 billion volume elements per minute, image data in the order of several terabytes were acquired for each embryo over the time course of an entire day, i.e. up to a stage, in which the embryo comprises 20,000 cells and major organs are in a functional state. By using automated image processing algorithms the image data of each embryo were converted into a digital representation of the embryo (the "digital embryo"), i.e. a database with comprehensive information about migratory tracks and divisions of the embryo's cells. The digital embryos permit to follow single cells as a function of time such that the "fate" as well as the origin of the cells can be reconstructed. By means of these analyses, developmental blueprints of tissues and organs can be determined in a whole-embryo context. Defects in embryonic development or disease models can now be analyzed and understood on a quantitative level.

  18. Regional localization of suspensor mRNAs during early embryo development.

    Science.gov (United States)

    Weterings, K; Apuya, N R; Bi, Y; Fischer, R L; Harada, J J; Goldberg, R B

    2001-11-01

    We investigated gene activity within the giant embryos of the scarlet runner bean (Phaseolus coccineus) to gain understanding of the processes by which the apical and basal cells become specified to follow different developmental pathways after division of the zygote. We identified two mRNAs, designated G564 and C541, that accumulate specifically within the suspensor of globular-stage embryos. G564 mRNA accumulates uniformly throughout the suspensor, whereas C541 mRNA accumulates to a higher level within the large basal cells of the suspensor that anchor the embryo to the surrounding seed tissue. Both G564 and C541 mRNAs begin to accumulate shortly after fertilization and are present within the two basal cells of embryos at the four-cell stage. In contrast, at the same stage, these mRNAs are not detectable within the two descendants of the apical cell. Nor are they detectable within cells of the embryo sac before fertilization, including the egg cell. We used a G564/beta-glucuronidase reporter gene to show that the G564 promoter is activated specifically within the basal region and suspensor of preglobular tobacco embryos. Analysis of the G564 promoter identified a sequence domain required for transcription within the suspensor that contains several copies of a conserved motif. These results show that derivatives of the apical and basal cells transcribe different genes as early as the four-cell stage of embryo development and suggest that the apical and basal cells are specified at the molecular level after division of the zygote.

  19. Regional Localization of Suspensor mRNAs during Early Embryo Development

    Science.gov (United States)

    Weterings, Koen; Apuya, Nestor R.; Bi, Yuping; Fischer, Robert L.; Harada, John J.; Goldberg, Robert B.

    2001-01-01

    We investigated gene activity within the giant embryos of the scarlet runner bean (Phaseolus coccineus) to gain understanding of the processes by which the apical and basal cells become specified to follow different developmental pathways after division of the zygote. We identified two mRNAs, designated G564 and C541, that accumulate specifically within the suspensor of globular-stage embryos. G564 mRNA accumulates uniformly throughout the suspensor, whereas C541 mRNA accumulates to a higher level within the large basal cells of the suspensor that anchor the embryo to the surrounding seed tissue. Both G564 and C541 mRNAs begin to accumulate shortly after fertilization and are present within the two basal cells of embryos at the four-cell stage. In contrast, at the same stage, these mRNAs are not detectable within the two descendants of the apical cell. Nor are they detectable within cells of the embryo sac before fertilization, including the egg cell. We used a G564/β-glucuronidase reporter gene to show that the G564 promoter is activated specifically within the basal region and suspensor of preglobular tobacco embryos. Analysis of the G564 promoter identified a sequence domain required for transcription within the suspensor that contains several copies of a conserved motif. These results show that derivatives of the apical and basal cells transcribe different genes as early as the four-cell stage of embryo development and suggest that the apical and basal cells are specified at the molecular level after division of the zygote. PMID:11701878

  20. [Study on embryo toxicity of Cinnabaris].

    Science.gov (United States)

    Liang, Aihua; Li, Chunying; Liu, Ting; Zhao, Yong; Cao, Chunyu; Xun, Baoyun; Wang, Jinhua

    2009-11-01

    To observe the effect of Cinnabaris on mouse embryos after pregnant mice were treated by Cinnabaris in different periods of pregnancy. Two separate experiments were performed: First, Cinnabaris was orally given into pregnant mice at the doses of 0.08, 0.4, 4.0 g x kg(-1) from D6 to D19 after pregnancy; Second, Cinnabaris was orally given into mice at the same doses mentioned above from D14 prior to pregnancy until D19 after pregnancy. All animals were sacrificed on D 20 of pregnancy by caesarean section. The numbers of survival, dead and absorbed fetuses were calculated and the survival fetus weight was measured. The survival fetuses were treated by two methods: One third survival fetuses were fixed and stained by Bouin solution for organ examination and the remaining two thirds fetuses were stained for skeleton examination. No obvious embryo toxicity was observed in the first experiment at Cinnabaris dose levels of 0.08, 0.4, or 4 g x kg(-1) x d(-1). There was no significant effect on embryonic development and the numbers of the survival, dead and absorbed fetus. No obvious malformations on appearance, organ, and skeleton examination of fetuses were found. The second experiment showed that the rates of abortion and absorbed fetus in 0.4, 4 g x kg(-1) x d(-1) Cinnabaris group were higher but without statistical significance compared with control group. Appearance and organ examination of Cinnabaris groups fetus showed no obvious malformation, but skeleton malformation was found in 0.4, 4 g x kg(-1) x d(-1) groups (the rates of skeleton malformation were 46.7% and 77.8%, respectively). No obvious embryonic development toxicity was observed when Cinnabaris was orally given in intermediate and late pregnant period, but the embryos in the early stage of pregnancy was more sensitive to Cinnabaris. When Cinnabaris was given prior to pregnancy until the whole period of pregnancy, it may be harmful for the fetuses at above the dose level 0.08 g x kg(-1) x d(-1) (equivalent

  1. Effect of diabetes mellitus on quality and quantity pregnant rat in Pre-implantation embryo development

    Directory of Open Access Journals (Sweden)

    fatemeh Javadnia

    2004-01-01

    Results: The cleavage rate in diabetic groups decreased (P<0.001 as 63% in compare to 94.8% of embryos reach to 2 cell stage on the second day of pregnancy and 38.1% in compare to 52.2% of embryo on thethird day have reach to 4 cell stage and 8.5% in compare to 78.2% of embryo on the pourth have reached to morula in normal and diabetic groups respectively. The number of embryos with best quality increased (P<0.0001 from 95.5% to 74.5% on second day and from 94.1% to 47.5% on third day three and from 88.9% to 8.5% on fourth day in normal group in compare to diabetic group respectively. Conclusion: IDDM in rat pregnancy mothers will causes significantly abnormality in quality of embryo as fragmentation and decrease in the number of embryo in compare to normal groups on the second day, third day, and fourth day of preimplantation period.

  2. Analysis of the expression of putatively imprinted genes in bovine peri-implantation embryos

    DEFF Research Database (Denmark)

    Tveden-Nyborg, Pernille Yde; Alexopoulos, N.I.; Cooney, M.A.

    2008-01-01

    The application of assisted reproductive technologies (ART) has been shown to induce changes in the methylation of the embryonic genome, leading to aberrant gene expression, including that of imprinted genes. Aberrant methylation and gene expression has been linked to the large offspring syndrome...... procedures, either by in vitro maturation, fertilization or culture. In conclusion, effects of genomic imprinting and of in vitro procedures for embryo production may influence the success of bovine embryo implantation....... (LOS) in bovine embryos resulting in increased embryonic morbidity and mortality. In the bovine, limited numbers of imprinted genes have been studied and studies have primarily been restricted to pre-implantation stages. This study reports original data on the expression pattern of 8 putatively...... imprinted genes (Ata3, Dlk1, Gnas, Grb10, Magel2, Mest-1, Ndn and Sgce) in bovine peri-implantation embryos. Two embryonic developmental stages were examined, Day 14 and Day 21. The gene expression pattern of single embryos was recorded for in vivo, in vitro produced (IVP) and parthenogenetic embryos...

  3. Conservation of methylation reprogramming in mammalian development: Aberrant reprogramming in cloned embryos

    Science.gov (United States)

    Dean, Wendy; Santos, Fátima; Stojkovic, Miodrag; Zakhartchenko, Valeri; Walter, Jörn; Wolf, Eckhard; Reik, Wolf

    2001-01-01

    Mouse embryos undergo genome-wide methylation reprogramming by demethylation in early preimplantation development, followed by remethylation thereafter. Here we show that genome-wide reprogramming is conserved in several mammalian species and ask whether it also occurs in embryos cloned with the use of highly methylated somatic donor nuclei. Normal bovine, rat, and pig zygotes showed a demethylated paternal genome, suggesting active demethylation. In bovine embryos methylation was further reduced during cleavage up to the eight-cell stage, and this reduction in methylation was followed by de novo methylation by the 16-cell stage. In cloned one-cell embryos there was a reduction in methylation consistent with active demethylation, but no further demethylation occurred subsequently. Instead, de novo methylation and nuclear reorganization of methylation patterns resembling those of differentiated cells occurred precociously in many cloned embryos. Cloned, but not normal, morulae had highly methylated nuclei in all blastomeres that resembled those of the fibroblast donor cells. Our study shows that epigenetic reprogramming occurs aberrantly in most cloned embryos; incomplete reprogramming may contribute to the low efficiency of cloning. PMID:11717434

  4. Parent-of-origin dependent gene-specific knock down in mouse embryos

    International Nuclear Information System (INIS)

    Iqbal, Khursheed; Kues, Wilfried A.; Niemann, Heiner

    2007-01-01

    In mice hemizygous for the Oct4-GFP transgene, the F1 embryos show parent-of-origin dependent expression of the marker gene. F1 embryos with a maternally derived OG2 allele (OG2 mat /-) express GFP in the oocyte and during preimplantation development until the blastocyst stage indicating a maternal and embryonic expression pattern. F1-embryos with a paternally inherited OG2 allele (OG2 pat /-) express GFP from the 4- to 8-cell stage onwards showing only embryonic expression. This allows to study allele specific knock down of GFP expression. RNA interference (RNAi) was highly efficient in embryos with the paternally inherited GFP allele, whereas embryos with the maternally inherited GFP allele showed a delayed and less stringent suppression, indicating that the initial levels of the target transcript and the half life of the protein affect RNAi efficacy. RT-PCR analysis revealed only minimum of GFP mRNA. These results have implications for studies of gene silencing in mammalian embryos

  5. Early somatic embryo induction events in alfalfa callus cultures

    International Nuclear Information System (INIS)

    El-Bakry, A.A.; Hildebrand, D.F.

    1987-01-01

    High and low regenerating alfalfa Medicago sativa L. cv Regen S full sibs were isolated from a callus culture screen on modified Blaydes medium. The average number of embryos per ovary were thirty and zero for the high and low genotypes respectively after six weeks in culture. Proembryonic cell masses (4-8 celled) were observed after 4-5 days in culture and maximum meristematic activity was at 6-7 days in culture, for the high regenerating genotypes. Well formed globular embryos, both epidermal and subepidermal in origin, were observed after 2 weeks is culture. Samples in culture for 3, 6 and 14 days from the high and low regenerating genotypes were radiolabeled in vivo with 35 S-methionine and run both on one and two dimension gels. The results will be discussed in relation to differences in proteins between the high and low regenerating genotypes at the stage of maximum meristematic activity (day 6) and differences occurring relative to the appearance of globular stage embryos (day 14) will be presented

  6. ADAM10 Is Involved in Cell Junction Assembly in Early Porcine Embryo Development.

    Directory of Open Access Journals (Sweden)

    Jeongwoo Kwon

    Full Text Available ADAM10 (A Disintegrin and Metalloprotease domain-containing protein 10 is a cell surface protein with a unique structure possessing both potential adhesion and protease domains. However, the role of ADAM10 in preimplantation stage embryos is not clear. In this study, we examined the expression patterns and functional roles of ADAM10 in porcine parthenotes during preimplantation development. The transcription level of ADAM10 dramatically increased from the morula stage onward. Immunostaining revealed that ADAM10 was present in both the nucleus and cytoplasm in early cleavage stage embryos, and localized to the apical region of the outer cells in morula and blastocyst embryos. Knockdown (KD of ADAM10 using double strand RNA did not alter preimplantation embryo development until morula stage, but resulted in significantly reduced development to blastocyst stage. Moreover, the KD blastocyst showed a decrease in gene expression of adherens and tight junction (AJ/TJ, and an increase in trophectoderm TJ permeability by disrupting TJ assembly. Treatment with an ADAM10 specific chemical inhibitor, GI254023X, at the morula stage also inhibited blastocyst development and led to disruption of TJ assembly. An in situ proximity ligation assay demonstrated direct interaction of ADAM10 with coxsackie virus and adenovirus receptor (CXADR, supporting the involvement of ADAM10 in TJ assembly. In conclusion, our findings strongly suggest that ADADM10 is important for blastocyst formation rather than compaction, particularly for TJ assembly and stabilization in preimplantation porcine parthenogenetic development.

  7. A computer program for calculation of approximate embryo/fetus radiation dose in nuclear medicine applications.

    Science.gov (United States)

    Bayram, Tuncay; Sönmez, Bircan

    2012-04-01

    In this study, we aimed to make a computer program that calculates approximate radiation dose received by embryo/fetus in nuclear medicine applications. Radiation dose values per MBq-1 received by embryo/fetus in nuclear medicine applications were gathered from literature for various stages of pregnancy. These values were embedded in the computer code, which was written in Fortran 90 program language. The computer program called nmfdose covers almost all radiopharmaceuticals used in nuclear medicine applications. Approximate radiation dose received by embryo/fetus can be calculated easily at a few steps using this computer program. Although there are some constraints on using the program for some special cases, nmfdose is useful and it provides practical solution for calculation of approximate dose to embryo/fetus in nuclear medicine applications. None declared.

  8. Polycyclic aromatic hydrocarbons affect survival and development of common snapping turtle (Chelydra serpentina) embryos and hatchlings

    International Nuclear Information System (INIS)

    Van Meter, Robin J.; Spotila, James R.; Avery, Harold W.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are toxic compounds found in the John Heinz National Wildlife Refuge in Philadelphia, Pennsylvania. We assessed the impact of PAHs and crude oil on snapping turtle development and behavior by exposing snapping turtle eggs from the Refuge and from three clean reference sites to individual PAHs or a crude oil mixture at stage 9 of embryonic development. Exposure to PAHs had a significant effect on survival rates in embryos from one clean reference site, but not in embryos from the other sites. There was a positive linear relationship between level of exposure to PAHs and severity of deformities in embryos collected from two of the clean reference sites. Neither righting response nor upper temperature tolerance (critical thermal maximum, CTM) of snapping turtle hatchlings with no or minor deformities was significantly affected by exposure to PAHs. - Exposure to polycyclic aromatic hydrocarbons on the egg reduces survival of snapping turtle embryos and causes developmental abnormalities

  9. PGF₂α levels in Day 8 blood plasma are increased by the presence of one or more embryos in the uterus.

    Science.gov (United States)

    Gomez, E; Martin, D; Carrocera, S; Muñoz, M

    2015-08-01

    In cattle, the detection of very early endometrial responses is considered to be hampered by the presence of only a single embryo. Therefore, we have previously developed a model of multiple embryo transfer to circumvent this hindrance. In this work, we analysed embryo-maternal interactions in the bovine uterus on day 8 of development while comparing the presence of multiple v. single embryos using embryo transfer and artificial insemination, respectively. Concentration of proteins (β-actin, NFkB, clusterin and immunoproteosome 20S β5i subunit-i20S), by western blot, and hexoses (glucose and fructose) were measured in paired samples of uterine fluid (UF) from the same animal with and without embryos in the uterus and were compared with UF obtained after artificial insemination. Prostaglandin (PG) F2 α and PGE2 concentrations were also analysed in blood plasma. The four proteins analysed and hexoses were unaffected by the presence of one or more embryos in the uterus. However, blood PGF2 α showed similar, significant increases with one or more embryos over cyclic animals; such changes were not observed in blood PGE2. Although multiple embryo transfer may appear to be non-physiological, we showed that the uterus, at the very early embryonic stages, does exhibit physiological reactions. Multiple embryo transfer can, therefore, be used for studies of very early embryo-maternal interactions in vivo in monotocous species.

  10. Piglets produced by transfer of vitrified porcine embryos after stepwise dilution of cryoprotectants.

    Science.gov (United States)

    Kobayashi, S; Takei, M; Kano, M; Tomita, M; Leibo, S P

    1998-02-01

    A total of 498 porcine embryos at various stages of development collected from superovulated gilts was used to investigate cryopreservation. First, blastocysts (BL), expanded blastocysts (ExB), and hatched blastocysts (HB) were used to determine the effect of exposure to concentrated solutions of ethylene glycol as cryoprotective additives (CPAs) on embryo survival. Then, survival of other embryos after vitrification by rapid cooling was determined. Based on their development after 48 h in culture, embryos were not injured by being exposed to 2.0 M ethylene glycol (EG) for 15 min or to 2.0 M EG for 5 min and then to a solution of 8.0 M EG in 7% polyvinylpyrrolidone (PVP) for 1 min. The CPAs were removed from the embryos by diluting them with 1.7 M galactose. To vitrify the embryos, they were exposed to 2.0 M EG for 5 min and then were pipetted directly into short columns of 8.0 M EG-PVP contained within (1.25-ml plastic straws and separated from long columns of 1.7 M galactose by an air bubble. The straws were plunged directly into LN2. After the straws were warmed rapidly in a 25 degrees C water bath, the embryos were immediately mixed with galactose within the straws by shaking them vigorously to mix the contents. In sequential experiments, three methods were used to dilute the CPA solutions. Method 1: Embryos in the EG-PVP-galactose mixture were expelled from the straws and rinsed and cultured in modified CZB medium (mCZB). Method II: Embryos in the mixture were placed briefly into 1.5 M EG and then rinsed and cultured in mCZB. Method III: Embryos in the mixture were rinsed in 1.0 M EG and then in 0.5 M EG and finally rinsed with mCZB and cultured. After 48 h in culture, the respective percentages of survival of embryos vitrified as BL, ExB, or HB were: Method I, 21, 32, and 13%; Method II, 9, 40, and 24%; Method III, 35, 85, and 71%. Of 20 additional ExB vitrified embryos diluted by Method III and transferred into a recipient, four developed into live piglets

  11. The effect of hepatocyte growth factor on mouse oocyte in vitro maturation and subsequent fertilization and embryo development

    Directory of Open Access Journals (Sweden)

    Mohammad H. Bahadori

    2011-05-01

    Full Text Available Background: Oocyte invitro maturation is an enormously promising technology for the treatment of infertility, yet its clinical application remains limited owing to poor success rates. Therefore, this study was devised to evaluate the effect of hepatocyte growth factor (HGF on in vitro maturation of immature mouse oocytes and resulting embryos development. Materials and Method: Cumulus – oocyte complex and germinal vesicle were obtained from eighteen 6-8 weeks-old female NMRI mice 46-48 hours after administration of an injection of 5 IU PMSG (Pregnant Mares’ Serum Gonadotrophin. Oocytes were culture in TCM199 (Tissue culture medium-199 supplemented with dosages of 0, 10, 20, 50 and 100 ng/ml of HGF. After 24 hours, metaphase ІІ oocytes were co-incubated with sperms for 4-6 hours in T6 medium. Following isolation of two pronucleus embryos, cleavage of embryos was assessed in the same medium till blastocyst stage. The number of oocytes and embryos was recorded under an invert microscope and the rate of oocyte maturation, fertilization and embryos cleavage until blastocyst stage compared using of student χ2 test. Results: In all compared groups, oocytes growth and embryos development rate in the 20 ng/ml of HGF treatment group was significantly higher (p<0.05 than the control group (p<0.05.Conclusion: 20 ng/ml of HGF improved the nuclear maturation and embryo development up to blastocyst stage during culture condition

  12. Seed Architecture Shapes Embryo Metabolism in Oilseed Rape[W][OA

    Science.gov (United States)

    Borisjuk, Ljudmilla; Neuberger, Thomas; Schwender, Jörg; Heinzel, Nicolas; Sunderhaus, Stephanie; Fuchs, Johannes; Hay, Jordan O.; Tschiersch, Henning; Braun, Hans-Peter; Denolf, Peter; Lambert, Bart; Jakob, Peter M.; Rolletschek, Hardy

    2013-01-01

    Constrained to develop within the seed, the plant embryo must adapt its shape and size to fit the space available. Here, we demonstrate how this adjustment shapes metabolism of photosynthetic embryo. Noninvasive NMR-based imaging of the developing oilseed rape (Brassica napus) seed illustrates that, following embryo bending, gradients in lipid concentration became established. These were correlated with the local photosynthetic electron transport rate and the accumulation of storage products. Experimentally induced changes in embryo morphology and/or light supply altered these gradients and were accompanied by alterations in both proteome and metabolome. Tissue-specific metabolic models predicted that the outer cotyledon and hypocotyl/radicle generate the bulk of plastidic reductant/ATP via photosynthesis, while the inner cotyledon, being enclosed by the outer cotyledon, is forced to grow essentially heterotrophically. Under field-relevant high-light conditions, major contribution of the ribulose-1,5-bisphosphate carboxylase/oxygenase–bypass to seed storage metabolism is predicted for the outer cotyledon and the hypocotyl/radicle only. Differences between in vitro– versus in planta–grown embryos suggest that metabolic heterogeneity of embryo is not observable by in vitro approaches. We conclude that in vivo metabolic fluxes are locally regulated and connected to seed architecture, driving the embryo toward an efficient use of available light and space. PMID:23709628

  13. Toxic effects of brominated indoles and phenols on zebrafish embryos.

    Science.gov (United States)

    Kammann, U; Vobach, M; Wosniok, W

    2006-07-01

    Organobromine compounds in the marine environment have been the focus of growing attention in past years. In contrast to anthropogenic brominated flame retardants, other brominated compounds are produced naturally, e.g., by common polychaete worms and algae. Brominated phenols and indoles assumed to be of biogenic origin have been detected in water and sediment extracts from the German Bight. These substances as well as some of their isomers have been tested with the zebrafish embryo test and were found to cause lethal as well as nonlethal malformations. The zebrafish test was able to detect a log K(OW)-related toxicity for bromophenols, suggesting nonpolar narcosis as a major mode of action. Different effect patterns could be observed for brominated indoles and bromophenols. The comparison of effective concentrations in the zebrafish embryo test with the concentrations determined in water samples suggests the possibility that brominated indoles may affect early life stages of marine fish species in the North Sea.

  14. Diagnosis of human preimplantation embryo viability.

    Science.gov (United States)

    Gardner, David K; Meseguer, Marcos; Rubio, Carmen; Treff, Nathan R

    2015-01-01

    Transfer of more than a single embryo in an IVF cycle comes with the finite possibility of a multiple gestation. Even a twin pregnancy confers significant risk to both mother and babies. The move to single-embryo transfer for all patients will be greatly facilitated by the ability to quantify embryo viability. Developments in time-lapse incubation systems have provided new insights into the developmental kinetics of the human preimplantation embryo. Advances in molecular methods of chromosomal analysis have created platforms for highly effective screening of biopsied embryos, while noninvasive analysis of embryo physiology reveals more about the embryo than can be determined by morphology alone. Recent developments in time-lapse microscopy, molecular karyotyping and in proteomics and metabolomics have been assessed and presented here in a descriptive review. New algorithms are being created for embryo selection based on their developmental kinetics in culture, and the impact of factors such as patient etiology and treatment are being clarified. Potential links between morphokinetic data and embryo karyotype are being elucidated. The introduction of new molecular methods of determining embryo chromosomal complement is proving to be accurate and reproducible, with the future trending toward CGH arrays or next generation sequencing as a rapid and reliable means of analysis, that should be suitable for each IVF clinic to adopt. A relationship between embryo metabolism and viability is established and is now being considered together with morphokinetic data to create more robust algorithms for embryo selection. Microfluidic devices have the capacity and potential to be used in human IVF clinics for the routine diagnosis of embryo biomarkers. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Timing of first embryonic cleavage is a positive indicator of the in vitro developmental potential of porcine embryos derived from in vitro fertilization, somatic cell nuclear transfer and parthenogenesis.

    Science.gov (United States)

    Isom, S Clay; Li, Rong Feng; Whitworth, Kristin M; Prather, Randall S

    2012-03-01

    Evidence in many species has suggested that those embryos that cleave earliest after fertilization are more developmentally competent than those that cleave relatively later after fertilization. Herein we document this phenomenon in porcine in vitro-fertilized (IVF), somatic cell nuclear transfer (SCNT), and parthenogenetic (PA) embryos. In vitro-matured pig oocytes were used to generate IVF, SCNT, and PA embryos. At 24 hr post-activation (or insemination; hpa/hpi), embryos were visually assessed, and cleaved embryos were moved into a new culture well. This process was repeated at 30 and 48 hpa/hpi. All embryos were allowed to develop 7 days in culture. For IVF embryos, 39.9%, 24.6%, and 10.5% of fast-, intermediate-, or slow-cleaving embryos, respectively, developed into blastocysts by day 7. For SCNT embryos, 31.8% of fast-, 5.7% of intermediate-, and 2.9% of late-cleaving embryos achieved the blastocyst stage of development. For PA embryos, the percentages of those cleaved embryos that developed to blastocyst were 59.3%, 36.7%, and 7.5% for early-, intermediate-, and late-cleaving embryos, respectively. Using RNA collected from early-, intermediate-, and late-cleaving embryos, real-time PCR was performed to assess the transcript levels of 14 different genes of widely varied function. The qPCR results suggest that maternal mRNA degradation may not proceed in an appropriate pattern in slow-cleaving embryos. These findings (1) confirm that, as observed in other species, earlier-cleaving porcine embryos are more successful at developing in culture than are slower-cleaving embryos, and (2) implicate mechanisms of maternal transcript destruction as potential determinants of oocyte/embryo quality. Copyright © 2011 Wiley Periodicals, Inc.

  16. SEM and x-ray microanalysis of cellular differentiation in Sea Urchin Embryos: a frozen hydrated study

    International Nuclear Information System (INIS)

    Klein, S.B.

    1985-12-01

    Quantitative studies of major chemical element distribution among individual differentiating cells were attempted using scanning electron microscopy. Frozen hydrated embryos of the sea urchin Strongelocentrotus purpuratus were examined at three stages: blastula, mesenchyme blastula, and early gastrula. The blastocoel matrix contained large beads of approximately 1 μm diameter. The cells of the archenteron lacked well defined cell boundaries. Characteristic levels of beam damage and charging provided structural information. The primary mesenchyme cells within the blastocoel were particularly susceptible to both effects. Damaging effects were noted in material stored in liquid nitrogen longer than three months. Ice crystal growth, shrinkage, elemental shift, density changes and charge accumulation may take place in these stored specimens. 151 refs., 50 figs., 3 tabs

  17. SEM and x-ray microanalysis of cellular differentiation in Sea Urchin Embryos: a frozen hydrated study

    Energy Technology Data Exchange (ETDEWEB)

    Klein, S.B.

    1985-12-01

    Quantitative studies of major chemical element distribution among individual differentiating cells were attempted using scanning electron microscopy. Frozen hydrated embryos of the sea urchin Strongelocentrotus purpuratus were examined at three stages: blastula, mesenchyme blastula, and early gastrula. The blastocoel matrix contained large beads of approximately 1 ..mu..m diameter. The cells of the archenteron lacked well defined cell boundaries. Characteristic levels of beam damage and charging provided structural information. The primary mesenchyme cells within the blastocoel were particularly susceptible to both effects. Damaging effects were noted in material stored in liquid nitrogen longer than three months. Ice crystal growth, shrinkage, elemental shift, density changes and charge accumulation may take place in these stored specimens. 151 refs., 50 figs., 3 tabs.

  18. Antisense inhibition of cyclin D1 expression is equivalent to flavopiridol for radiosensitization of zebrafish embryos

    International Nuclear Information System (INIS)

    Purpose: Flavopiridol, a small molecule pan-cyclin inhibitor, has been shown to enhance Radiation response of tumor cells both in vitro and in vivo. The clinical utility of flavopiridol, however, is limited by toxicity, previously attributed to pleiotropic inhibitory effects on several targets affecting multiple signal transduction pathways. Here we used zebrafish embryos to investigate radiosensitizing effects of flavopiridol in normal tissues. Methods and Materials: Zebrafish embryos at the 1- to 4-cell stage were treated with 500 nM flavopiridol or injected with 0.5 pmol antisense hydroxylprolyl-phosphono nucleic acid oligomers to reduce cyclin D1 expression, then subjected to ionizing radiation (IR) or no radiation. Results: Flavopiridol-treated embryos demonstrated a twofold increase in mortality after exposure to 40 Gy by 96 hpf and developed distinct radiation-induced defects in midline development (designated as the 'curly up' phenotype) at higher rates when compared with embryos receiving IR only. Cyclin D1-deficient embryos had virtually identical IR sensitivity profiles when compared with embryos treated with flavopiridol. This was particularly evident for the IR-induced curly up phenotype, which was greatly exacerbated by both flavopriridol and cyclin D1 downregulation. Conclusions: Treatment of zebrafish embryos with flavopiridol enhanced radiation sensitivity of zebrafish embryos to a degree that was very similar to that associated with downregulation of cyclin D1 expression. These results are consistent with the hypothesis that inhibition of cyclin D1 is sufficient to account for the radiosensitizing action of flavopiridol in the zebrafish embryo vertebrate model

  19. Use of Gammarus fossarum (Amphipoda) embryo for toxicity testing: A case study with cadmium.

    Science.gov (United States)

    Arambourou, Hélène; Decamps, Alexandre; Quéau, Hervé; Dabrin, Aymeric; Neuzeret, Didier; Chaumot, Arnaud

    2017-09-01

    The effects of environmental contaminants on arthropod embryo stages have been poorly investigated in ecotoxicology. Moreover, many of these tests used hatching success as the sole metric, although it is possible to detect many more subtle effects. After a detailed description of embryogenesis in Gammarus fossarum, the present study reports on the sublethal effects of cadmium (Cd) exposure during embryonic development in G. fossarum. Embryos were first directly exposed in multiwell plates throughout the entire embryonic cycle (23 d) to increasing Cd concentrations (0, 1.5, and 3.0 μg/L; 120 embryos/concentration). Then, to assess the representativeness of the gammarid embryo assay performed in multiwell plates, embryos were exposed to similar Cd concentrations through the maternal open brood pouch. Next, to pinpoint sensitive periods of development, embryos were directly exposed to 3.0 μg/L of Cd for shorter periods of time: during gastrulation, organogenesis, and hatching. After hatching, the following parameters were measured in the newborn individuals: 1) body mass; 2) activity of the enzyme phenoloxidase, a key enzyme of the arthropod immune system; and 3) locomotor activity. Phenoloxidase activity was strongly inhibited in newborn individuals of embryos exposed (either in multiwell plates or in the maternal brood pouch) to 3.0 μg/L Cd throughout embryonic development. Furthermore, strong detrimental locomotor effects were observed in newborn individuals of embryos directly exposed to 3.0 μg/L. Exposures for shorter periods of time were not sufficient to induce such effects; no sensitive period could be determined. By bringing new insights into a critical time window of exposure, the gammarid embryo assay could provide a novel and interesting addition to existing bioassays in gammarids. Environ Toxicol Chem 2017;36:2436-2443. © 2017 SETAC. © 2017 SETAC.

  20. Manganese interferes with calcium, perturbs ERK signaling, and produces embryos with no skeleton.

    Science.gov (United States)

    Pinsino, Annalisa; Roccheri, Maria Carmela; Costa, Caterina; Matranga, Valeria

    2011-09-01

    Manganese (Mn) has been associated with embryo toxicity as it impairs differentiation of neural and skeletogenic cells in vertebrates. Nevertheless, information on the mechanisms operating at the cellular level remains scant. We took advantage of an amenable embryonic model to investigate the effects of Mn in biomineral formation. Sea urchin (Paracentrotus lividus) embryos were exposed to Mn from fertilization, harvested at different developmental stages, and analyzed for their content in calcium (Ca), expression of skeletogenic genes, localization of germ layer markers, and activation of the extracellular signal-regulated kinase (ERK). By optical and immunofluorescence microscopy, we found that Mn exposure produced embryos with no skeleton, by preventing the deposition of the triradiate calcitic spicules usually produced only by specialized mesoderm cells. On the contrary, ectoderm and endoderm differentiation was not impaired. Endogenous Ca content in whole embryos and its localization in Golgi regions of skeletogenic cells was strongly reduced, as measured by atomic absorption spectrometry and in vivo calcein labeling. Spicule-lacking embryos showed persistent ERK activation by immunocytochemistry and immunoblotting, contrary to the physiological oscillations observed in normal embryos. The expression of the skeletogenic genes, Pl-msp130 and Pl-sm30, was also differentially affected if compared with controls. Here, we showed for the first time the ability of Mn to interfere with Ca uptake and internalization into skeletogenic cells and demonstrate that Ca content regulates ERK activation/inactivation during sea urchin embryo morphogenesis. The use of Mn-exposed sea urchin embryos as a new model to study signaling pathways occurring during skeletogenesis will provide new insights into the mechanisms involved in Mn embryo toxicity and underlie the role of calcium in the biomineralization process in vertebrates.

  1. A prospective randomized comparison of early embryo cleavage kinetics between two media culture systems

    Science.gov (United States)

    Zhang, Huan; Zheng, Yi; Wu, Yonggen; Ye, Danna; Huang, Xuefeng

    2016-01-01

    Objective: To investigate whether early embryo cleavage kinetics were affected by type of culture media. Methods: In this prospective sibling-split study, 620 oocytes from 37 patients were randomly allocated into two groups: Cook group and Vitrolife group. Oocytes/embryos in Cook group, would be cultured with Cook sequential culture medium, while oocytes/embryos in Vitrolife group, would be cultured with Vitrolife sequential culture medium. Time-lapse imaging technology was used to calculate exact timing of early embryo cleavage events which included time to 2PN breakdown, cleavage to 2-, 3-, 4-, 5- cell and the time duration in the 2-,3-cell stage. Then these timing of early embryo cleavage events were compared between Cook group and Vitrolife group. Moreover, fertilization rate, cleavage rate, high quality embryo rate, usable blastocyst rate, pregnancy rate and implantation rate of these two groups were also analyzed. Results: The results showed there were no differences in all timing of early embryo cleavage events between the two groups. In addition, the two groups were similar in fertilization rate (Cook 71.0% vs. Vitrolife 71.3%, P>0.05), cleavage rate (Cook 98.1% vs. Vitrolife 98.2%, P>0.05), high quality embryo rate (Cook 52.1% vs. Vitrolife 52.7%, P>0.05), usable blastocyst rate (Cook 29.7% vs. Vitrolife 28.0%, P>0.05), pregnancy rate (Cook 46.7% VS. Vitrolife 50.0%, P>0.05) and implantation rate (Cook 30.3% VS. Vitrolife 29.0%, P>0.05). Conclusions: Morphokinetics used for embryo selection are not affected by the two different culture media. PMID:28083029

  2. Dynamic Subcellular Localization of Iron during Embryo Development in Brassicaceae Seeds

    Directory of Open Access Journals (Sweden)

    Miguel A. Ibeas

    2017-12-01

    Full Text Available Iron is an essential micronutrient for plants. Little is know about how iron is loaded in embryo during seed development. In this article we used Perls/DAB staining in order to reveal iron localization at the cellular and subcellular levels in different Brassicaceae seed species. In dry seeds of Brassica napus, Nasturtium officinale, Lepidium sativum, Camelina sativa, and Brassica oleracea iron localizes in vacuoles of cells surrounding provasculature in cotyledons and hypocotyl. Using B. napus and N. officinale as model plants we determined where iron localizes during seed development. Our results indicate that iron is not detectable by Perls/DAB staining in heart stage embryo cells. Interestingly, at torpedo development stage iron localizes in nuclei of different cells type, including integument, free cell endosperm and almost all embryo cells. Later, iron is detected in cytoplasmic structures in different embryo cell types. Our results indicate that iron accumulates in nuclei in specific stages of embryo maturation before to be localized in vacuoles of cells surrounding provasculature in mature seeds.

  3. The Chromosomal Constitution of Embryos Arising from Monopronuclear Oocytes in Programmes of Assisted Reproduction

    Directory of Open Access Journals (Sweden)

    Bernd Rosenbusch

    2014-01-01

    Full Text Available The assessment of oocytes showing only one pronucleus during assisted reproduction is associated with uncertainty. A compilation of data on the genetic constitution of different developmental stages shows that affected oocytes are able to develop into haploid, diploid, and mosaic embryos with more or less complex chromosomal compositions. In the majority of cases (~80%, haploidy appears to be caused by gynogenesis, whereas parthenogenesis or androgenesis is less common. Most of the diploid embryos result from a fertilization event involving asynchronous formation of the two pronuclei or pronuclear fusion at a very early stage. Uniparental diploidy may sometimes occur if one pronucleus fails to develop and the other pronucleus already contains a diploid genome or alternatively a haploid genome undergoes endoreduplication. In general, the chance of obtaining a biparental diploid embryo appears higher after conventional in vitro fertilization than after intracytoplasmic sperm injection. If a transfer of embryos obtained from monopronuclear oocytes is envisaged, it should be tried to culture them up to the blastocyst since most haploid embryos are not able to reach this stage. Comprehensive counselling of patients on potential risks is advisable before transfer and a preimplantation genetic diagnosis could be offered if available.

  4. Expression of nucleolar-related proteins in porcine preimplantation embryos produced in vivo and in vitro

    DEFF Research Database (Denmark)

    Bjerregaard, Bolette; Wrenzycki, Christine; Strejcek, Frantisek

    2004-01-01

    The expression of nucleolar-related proteins was studied as an indirect marker of the ribosomal RNA (rRNA) gene activation in porcine embryos up to the blastocyst stage produced in vivo and in vitro. A group of the in vivo-developed embryos were cultured with alpha-amanitin to block the de novo...... proteins pRb and p130, which are involved in cell-cycle regulation, was assessed by semiquantitative RT-PCR up to the blastocyst stage. Toward the end of third cell cycle, the nuclei in non-alpha-amanitin-treated, in vivo-produced embryos displayed different stages of transformation of the nuclear...... was delayed in porcine embryos produced in vitro compared to the in vivo-derived counterparts with respect to mRNAs encoding PAF53 and UBF. Moreover, differences existed in the mRNA expression patterns of pRb between in vivo- and in vitro-developed embryos. These findings show, to our knowledge for the first...

  5. Structural and electronic effects in acetone adsorption over TiO2 anatase clusters as the first stage of photocatalytic oxidation

    Science.gov (United States)

    Vorontsov, Alexander V.

    2017-09-01

    Photocatalytic oxidation is used for air purification from low concentrations of organic compounds and microbiological objects. Adsorption is the first stage of photocatalytic oxidation, and adsorption constant value has direct linear influence onto the rate of oxidation at low concentration according to the Langmuir-Hinshelwood equation. The present computational investigation has been undertaken with the goal to estimate the effect of nanoparticle size in the range of 1-1.5 nm, extent of hydroxylation, surface acidity, and nanoparticle shape on adsorption of acetone over TiO2 anatase particle facets, edges, and vertices. The anatase nanoparticles were represented by three cluster models—two of cubic shape and one of decahedral shape with exposed surfaces (001), (100), and (101). Adsorption energy was calculated with density functional tight binding (DFTB) semiempirical method and varied from - 0.67 to - 25.79 kcal/mol for different sites of the clusters depending on facet types and location on a facet. Mean unweighted adsorption energy of acetone increased from - 4.49 to - 8.16 kcal/mol for (001) facet and from - 11.05 to - 12.97 kcal/mol for (100) facet when the cubic cluster size increased from 3 × 3 × 1 to 4 × 4 × 1 elementary cells. For decahedral cluster, mean adsorption energy on (001) facet was - 9.87 kcal/mol and - 14.44 kcal/mol on (101) facets. The largest adsorption energy - 25.60 and - 25.79 kcal/mol was observed on grove Ti atoms on (100) facet of the largest cubic cluster and vertex atoms in decahedral cluster, respectively. Dissociative adsorption of one and two water molecules on (001) facet increased acetone adsorption energy from - 4.02 to - 8.20 and to - 18.50 kcal/mol. A marked electronic effect on adsorption energy was observed for two adjacent sites on (001) facet with a similar structure but adsorption energy - 16.40 and - 1.40 kcal/mol. Influence of acetone adsorption on clusters' band gap, photogenerated thermalized electron and

  6. Developmental regulation and modulation of apoptotic genes expression in sheep oocytes and embryos cultured in vitro with L-carnitine.

    Science.gov (United States)

    Mishra, A; Reddy, I J; Gupta, Psp; Mondal, S

    2016-12-01

    The objective of this study was to find out the impact of L-carnitine (10 mM) on developmental regulation of preimplantation sheep embryos cultured in vitro when supplemented in maturation medium and post-fertilization medium separately. Subsequent objective was to observe the L-carnitine-mediated alteration in expression of apoptotic genes (Bcl2, Bax, Casp3 and PCNA) in sheep oocytes and developing embryos produced in vitro. Oocytes matured with L-carnitine showed significantly (p embryos cultured with actinomycin D and TNFα showed developmental arrest with significant (p embryo development and supplementation of L-carnitine during IVM altered the expression of apoptotic genes in the developmental stages of embryos. © 2016 Blackwell Verlag GmbH.

  7. Nucleolar remodeling in nuclear transfer embryos

    DEFF Research Database (Denmark)

    Laurincik, Jozef; Maddox-Hyttel, Poul

    2007-01-01

    nucleoli are not apparent until the 5th cell cycle, whereas in somatic cell nuclear transfer embryos the functional nucleoli emerge already during the 3rd cell cycle. Intergeneric reconstructed embryos produced by the fusion of bovine differentiated somatic cell to a nonactivated ovine cytoplast fail...... the developmental potential of embryos originating from varied nuclear transfer protocols. In bovine in vivo developed embryos, functional ribosome-synthesizing nucleoli become structurally distinct toward the end of the 4th post-fertilization cell cycle. In embryonic cell nuclear transfer embryos, fully developed...... is completed toward the end of the 4th cell cycle. A substantial proportion of bovine embryos produced by nuclear transfer of embryonic or somatic cells to bovine ooplasts display aberrations in protein localization in one or more blastomers. This information is indicative of underlying aberrations in genomic...

  8. Ultrastructure of endothelium in ovules of Penstemon gentianoides Poir. (Scrophulariaceae) at mature embryo sac phase.

    Science.gov (United States)

    Dane, Feruzan; Olgun, Göksel; Ekici, Nuran

    2007-06-01

    In this study ultrastructural differences between endothelial cells of different location in Penstemon gentianoides have been examined with electron microscope at mature embryo sac phase. Embryo sac is of the Polygonum type and surrounded by endothelium except the micropylar region. The cuticle is located primarily around the chalazal three-fourths of the embryo sac. Endothelium cells around the chalaza and toward the micropylar region are rich in cytoplasmic organelles. The cytoplasm of endothelial cells near the central cell has large vacuoles and few organelles. There are also plasmodesmas on the anticlinal walls of endothelial cells. The endothelium and the micropylar integumentary cells play a role in transport of metabolites into the embryo sac.

  9. Nickel affects gill and muscle development in oriental fire-bellied toad (Bombina orientalis) embryos

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Jin; Song, Sang Ha; Kim, Dae Han; Gye, Myung Chan, E-mail: mcgye@hanyang.ac.kr

    2017-01-15

    Highlights: • Nickel inhibited the development of external gill in B. orientalis embryos. • The 168 h LC{sub 50} and EC{sub 50} values of nickel were 33.8 and 5.4 μM, respectively, in embryos. • Nickel induced abnormal tail development of embryos. • NF stage 26–31 was the most sensitive window for embryos to nickel exposure. • Nickel affected the calcium-dependent myogenic gene expression in embryos. - Abstract: The developmental toxicity of nickel was examined in the embryos of Bombina orientalis, a common amphibian in Korea. Based on a standard frog embryo teratogenesis assay, the LC{sub 50} and EC{sub 50} for malformation of nickel after 168 h of treatment were 33.8 μM and 5.4 μM, respectively. At a lethal concentration (100 μM), nickel treatment decreased the space between gill filaments and caused epithelial swelling and abnormal fusion of gill filaments. These findings suggest that nickel affects the functional development of gills, leading to embryonic death. At sublethal concentrations (1–10 μM), nickel produced multiple embryonic abnormalities, including bent tail and tail dysplasia. At 10 μM, nickel significantly decreased tail length and tail muscle fiber density in tadpoles, indicating inhibition of myogenic differentiation. Before hatching, the pre-muscular response to muscular response stages (stages 26–31) were the most sensitive period to nickel with respect to tail muscle development. During these stages, MyoD mRNA was upregulated, whereas myogenic regulatory factor 4 mRNA was downregulated by 0.1 μM nickel. Calcium-dependent kinase activities in muscular response stage embryos were significantly decreased by nickel, whereas these activities were restored by exogenous calcium. In tadpoles, 10 μM nickel significantly decreased the expression of the myosin heavy chain and the 12/101 muscle marker protein in the tail. Expression was restored by exogenous calcium. Our results indicate that nickel affects muscle development by

  10. Evolution of Electronic Properties of (Cu(In,Ga)Se2 (CIGS)-Based Solar Cells During a 3-Stage Growth Process: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    AbuShama, J. A.; Johnston, S.; Ahrenkiel, R.; Crandall, R.; Young, D.; Noufi, R.

    2003-04-01

    We investigated the electronic properties of ZnO/CdS/CIGS /Mo/SLG polycrystalline thin-film solar cells with compositions ranging from Cu-rich to In(Ga)-rich by deep-level transient spectroscopy (DLTS) and capacitance-voltage (C-V) measurements. This compositional change represents the evolution of the film during growth by the 3-stage process. Two sets (four samples each) of CIGS thin films were prepared with Ga/(In+Ga) ratios of~0.3 (low Ga) and~0.6 (high Ga). The Cu/(In+Ga) ratio ranges from 1.24 (Cu-rich) to 0.88 (In(Ga)-rich). The films were treated with NaCN to remove the Cu2-xSe phase where needed. Key results include: (1) For low-Ga devices, DLTS data show that acceptor-like traps dominate in samples where CIGS grains do not go through the Cu-rich to In(Ga)-rich transition, whereas donor-like traps dominate in In(Ga)-rich samples. Therefore, we see a clear transformation of defects from acceptor-like to donor-like traps. The activation energies of these traps range from 0.12 to 0.63 eV. We also observed that NaCN treatment eliminates a deep minority trap in the In(Ga)-rich devices, (2) For high-Ga devices, only majority-carrier traps were detected. These traps again range from shallow to deep, (3) The carrier concentration around the junction and the density of traps decrease as the CIGS becomes more In(Ga)-rich.

  11. Somatic embryogenesis and plant regeneration from embryo rescue ...

    African Journals Online (AJOL)

    The application of tissue culture techniques, particularly in the area of embryo rescue, has had a major impact on the maintenance and development of hybrid embryo from wide crosses. Embryo rescue techniques are directed towards obtaining more efficient survival of embryos in situations where very immature embryos ...

  12. Methanol as a cryoprotectant for equine embryos.

    Science.gov (United States)

    Bass, L D; Denniston, D J; Maclellan, L J; McCue, P M; Seidel, G E; Squires, E L

    2004-09-15

    Equine embryos (n=43) were recovered nonsurgically 7-8 days after ovulation and randomly assigned to be cryopreserved in one of two cryoprotectants: 48% (15M) methanol (n=22) or 10% (136 M) glycerol (n=21). Embryos (300-1000 microm) were measured at five intervals after exposure to glycerol (0, 2, 5, 10 and 15 min) or methanol (0, 15, 35, 75 and 10 min) to determine changes (%) in diameter over time (+/-S.D.). Embryos were loaded into 0.25-ml plastic straws, sealed, placed in a programmable cell freezer and cooled from room temperature (22 degrees C) to -6 degrees C. Straws were then seeded, held at -6 degrees C for 10 min and then cooled to -33 degrees C before being plunged into liquid nitrogen. Two or three embryos within a treatment group were thawed and assigned to be either cultured for 12 h prior to transfer or immediately nonsurgically transferred to a single mare. Embryo diameter decreased in all embryos upon initial exposure to cryoprotectant. Embryos in methanol shrank and recovered slightly to 76+/-8 % of their original diameter; however, embryos in glycerol continued to shrink, reaching 57+/-6 % of their original diameter prior to cryopreservation. Survival rates of embryos through Day 16 of pregnancy were 38 and 23%, respectively (P>0.05) for embryos cryopreserved in the presence of glycerol or methanol. There was no difference in pregnancy rates of mares receiving embryos that were cultured prior to transfer or not cultured (P>0.05). Preliminary experiments indicated that 48% methanol was not toxic to fresh equine embryos but methanol provided no advantage over glycerol as a cryoprotectant for equine blastocysts.

  13. Proteome profiling of embryo chick retina

    OpenAIRE

    Mizukami, Mina; Kanamoto, Takashi; Souchelnytskyi, Nazariy; Kiuchi, Yoshiaki

    2008-01-01

    Abstract Background Little is known regarding the molecular pathways that underlie the process of retinal development. The purpose of this study was to identify proteins which may be involved in development of retina. We used a proteomics-based approach to identify proteins that are up- or down-regulated during the development of the embryo chick retina. Results Two-dimensional gel electrophoresis was performed with the retina of embryo chicken, which was obtained from embryos of day 7 (ED7) ...

  14. Die Behandlung menschliches Embryos und Menschenwurde

    OpenAIRE

    Matsui, Fumio

    2002-01-01

    We are confronted with an old and new problem, which has come up with the progress of modern biotechnologies: what is a life or when does a life begin? The expectation of order-made medicine has build up since the discovery of Embryo Stem cell called "a dream master cell", while there is any condemnation against the destruction of human embryo in order to gain it. It is a question whether a human embryo is a human being in the world. Human dignity(=HD) is a principle that keeps human embryos ...

  15. Theory about the Embryo Cryo-Treatment.

    Science.gov (United States)

    Vladimirov, Iavor K; Tacheva, Desislava; Diez, Antonio

    2017-04-01

    To create hypothesis, which can give a logical explanation related to the benefits of freezing/thawing embryos. Cryopreservation is not only a technology used for storing embryos, but also a method of embryo treatment that can potentially improve the success rate in infertile couples. From the analysis of multiple results in assisted reproductive technology, which have no satisfactory explanation to date, we found evidence to support a 'therapeutic' effect of the freezing/thawing of embryos on the process of recovery of the embryo and its subsequent implantation. Freezing/thawing is a way to activate the endogenous survival and repair responses in preimplantation embryos. Several molecular mechanisms can explain the higher success rate of ET using thawed embryos compared to fresh ET in women of advanced reproductive age, the higher miscarriage rate in cases of thawed blastocyst ET compared to thawed ET at early cleavage embryo, and the higher perinatal parameters of born children after thawed ET. Embryo thawing induces a stress. Controlled stress is not necessarily detrimental, because it generates a phenomenon that is counteracted by several known biological responses aimed to repair mitochondrial damage of membrane and protein misfolding. The term for favorable biological responses to low exposures to stress is called hormesis. This thesis will summarize the role of cryopreservation in the activation of a hormetic response, preserving the mitochondrial function, improving survival, and having an impact on the process of implantation, miscarriage, and the development of pregnancy.

  16. Nano-nutrition of chicken embryos

    DEFF Research Database (Denmark)

    Sawosz, Filip; Pineda, Lane Manalili; Hotowy, Anna

    2013-01-01

    It has been suggested that the quantity and quality of nutrients stored in the egg might not be optimal for the fast rate of chicken embryo development in modern broilers, and embryos could be supplemented with nutrients by in ovo injection. Recent experiments showed that in ovo feeding reduces...... broiler eggs was randomly divided into a Control group without injection and injected groups with hydrocolloids of Nano-Ag, ATP or a complex of Nano-Ag and ATP (Nano-Ag/ATP). The embryos were evaluated on day 20 of incubation. The results indicate that the application of ATP to chicken embryos increases...

  17. Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1989-01-01

    Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

  18. Developmental kinetics of the first cell cycles of bovine in vitro produced embryos in relation to their in vitro viability and sex

    DEFF Research Database (Denmark)

    Holm, Peter; Shukri, N. M.; Vajta, Gábor

    1998-01-01

    The development of bovine IVP-embryos was observed in a time-lapse culture system to determine cell cycle lengths of 1) embryos that developed into compact morulae (CM) or blastocysts (BL) within 174 h after insemination (viable), 2) embryos that arrested during earlier stages (nonviable) and 3...... were included (n=392), and the times of cleavage events noted. After culture, 100 CM or BL were randomly selected for sexing by PCR. BL developed equally well in the time-lapse and control culture systems (36 vs 38. The respective lengths of the first 4 cell cycles of viable embryos were 32.0 + 3.9, g...

  19. Radiation- and drug-induced DNA repair in mammalian oocytes and embryos

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, R A; Brandriff, B

    1979-01-01

    A review of studies showing ultraviolet- or drug-induced unscheduled DNA synthesis in mammalian oocytes and embryos suggests that the female gamete has an excision repair capacity from the earliest stages of oocyte growth. The oocyte's demonstrable excision repair capacity decreases at the time of meiotic maturation for unknown reasons, but the fully mature oocyte maintans a repair capacity, in contrast to the mature sperm, and contributes this to the zygote. Early embryo cells maintain relatively constant levels of excision repair until late fetal stages, when they lose their capacity for excision repair. These apparent changes in excision repair capacity do not have a simple relationship to known differences in radiation sensitivity of germ cells and embryos.

  20. Radiation- and drug-induced DNA repair in mammalian oocytes and embryos

    International Nuclear Information System (INIS)

    Pedersen, R.A.; Brandriff, B.

    1979-01-01

    A review of studies showing ultraviolet- or drug-induced unscheduled DNA synthesis in mammalian oocytes and embryos suggests that the female gamete has an excision repair capacity from the earliest stages of oocyte growth. The oocyte's demonstrable excision repair capacity decreases at the time of meiotic maturation for unknown reasons, but the fully mature oocyte maintans a repair capacity, in contrast to the mature sperm, and contributes this to the zygote. Early embryo cells maintain relatively constant levels of excision repair until late fetal stages, when they lose their capacity for excision repair. These apparent changes in excision repair capacity do not have a simple relationship to known differences in radiation sensitivity of germ cells and embryos

  1. POST-HARVEST EMBRYO DEVELOPMENT IN GINSENG SEEDS INCREASES DESICCATION SENSITIVITY AND NARROWS THE HYDRATION WINDOW FOR CRYOPRESERVATION.

    Science.gov (United States)

    Han, E; Popova, E; Cho, G; Park, S; Lee, S; Pritchard, H W; Kim, H H

    Despite its self-pollinating characteristics, Korean ginseng germplasm is mainly maintained in clonal gene banks as there is no defined approach to the long-term conservation of its seed, including the most appropriate stage of embryo development for storage. The aim of this study was to reveal the effect of embryo development on desiccation tolerance and cryopreservation success in ginseng seeds. Seeds of Korean ginseng (Panax ginseng C.A. Meyer) at three post-harvest stages (immediately after harvesting and following treatments to enable internal growth of the embryo) were desiccated and cryopreserved. The hydration window for the >80% dehiscence and germination of cryopreserved ginseng seeds varied with embryo developmental stage: 3-9% moisture content (MC) for both unpulped and undehisced seeds when the embryo was 0.1 the length of the endosperm, 7-10% MC for dehisced seeds (0.5 embryo:endosperm) and 9-11% MC for seeds with fully developed embryos (0.9 embryo:endosperm). Whilst dried (4-8% moisture content) and undehisced seeds within fruits (unpulped seeds) lost more than half their viability during 1 year's storage at room temperature, cryopreservation enabled germination levels of c. 90%. Overall, 432 accessions of Korean ginseng landraces have been cryopreserved using undehisced seeds with or without fruits. Post-harvest treatment of Korean ginseng seeds to enable embryo development decreases tolerance of very low MCs, and thus narrows the hydration window for cryopreservation. Fresh-harvested and unpulped seeds that have been dried to c. 5% MC are recommended for long-term cryogenic storage.

  2. Numerical calculations for diffusion effects in the well-of-the-well culture system for mammalian embryos.

    Science.gov (United States)

    Matsuura, Koji

    2014-06-01

    Recent studies suggest that the microenvironment and embryo density used during embryo culture considerably affect development to the blastocyst stage. High embryo density allows for autocrine secretions to diffuse to neighbouring embryos during group culture, with a positive effect on further development. A variation of group culture is the well-of-the-well (WOW) culture system, allowing for individual identification of embryos cultured in small holes in a microdroplet. Bovine blastocyst development is higher in the WOW culture system than in conventional group culture. To compare the concentration of chemical factors between conventional and WOW culture, a model was constructed to calculate the concentration of secreted factors based on Fick's second law of diffusion using spreadsheet software. Furthermore, model was used to determine the concentration of growth factors and waste materials adjacent to the embryo periphery. The results of these calculations suggest that the highest difference in the concentration of secreted small molecules and macromolecules was at the most two- to threefold, with the concentrations reduced more and diffusion kinetics facilitated to a greater extent in the WOW culture system. The average ratio of the concentration of secreted macromolecules (10nm diameter) around the embryos was also compared between systems with well widths of 0.1 and 0.3mm. The concentration of secreted materials surrounding embryos increased in a narrow tapered well. The findings suggest that the WOW culture system is better than conventional group culture because of the increased final concentration of autocrine factors and higher diffusion kinetics of waste materials.

  3. Development beyond the gastrula stage and digestive organogenesis in the apple-snail Pomacea canaliculata (Architaenioglossa, Ampullariidae).

    Science.gov (United States)

    Koch, E; Winik, B C; Castro-Vazquez, A

    2009-04-01

    Development of Pomacea canaliculata from the gastrula stage until the first day after hatching is described. Trochophore embryos are developed after gastrulation, showing the prototroch as a crown of ciliated orange-brownish cells. However, no true veliger embryos are formed, since the prototroch does not fully develop into a velum. Afterward, the connection between the fore- and midgut is permeated and the midgut becomes full of the pink-reddish albumen, which is stored into a central archenteron's lake, from where it is accumulated into the large cells forming the midgut wall ("giant cells"). Electron microscopy of giant cells in late embryos showed that albumen is engulfed by large endocytic vesicles formed between the irregular microvilli at the top of these cells. By the end of intracapsular development, giant cells become gradually replaced by two new epithelial cell types which are similar to those found in the adult midgut gland: the pre-columnar and the pre-pyramidal cells. Pre-columnar cells have inconspicuous basal nuclei and are crowned by stereocilia, between which small endocytic vesicles are formed. Pre-pyramidal cells have large nuclei with 2-3 nucleoli and show a striking development of the rough endoplasmic reticulum. The genesis of the three cell lineages (giant, pre-columnar and pre-pyramidal cells) is hypothetically attributed to epithelial streaks that occur at both sides of the midgut since early stages of development.

  4. Adoption first? The disposition of human embryos.

    Science.gov (United States)

    Murphy, Timothy F

    2014-06-01

    Anja Karnein has suggested that because of the importance of respect for persons, law and policy should require some human embryos created in vitro to be available for adoption for a period of time. If no one comes forward to adopt the embryos during that time, they may be destroyed (in the case of embryos left over from fertility medicine) or used in research (in the case of embryos created for that purpose or left over from fertility medicine). This adoption option would increase the number of embryos available for couples looking for help in having children, but that effect is less important--Karnein argues--than the observance of respect for human persons. As possible persons, she holds that embryos ought to be treated, as if they will become children, if only for a while. If enacted as a matter of law and policy, an 'adoption option' would wrongly interfere with the dispositional rights women and men ought to have over embryos they create in the course of trying to have children. Karnein's proposal would also deprive researchers of certainty that the embryos they create for research would actually be available that way, leading to increased burdens of time and money and maybe even to more embryos than would otherwise be produced. Karnein's analysis does not show, moreover, that any duty of rescue applies to embryos. No woman is required to adopt any embryo, which significantly undercuts the justification for an obligatory adoption period. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. 9 CFR 98.16 - The embryo collection unit.

    Science.gov (United States)

    2010-01-01

    ... breeding them (either natural breeding or artificial insemination). (b) Embryo collection area. The embryo... equipment used for artificial insemination or for collection, processing, or storage of embryos. The walls...

  6. [Limitations and controversies in determining the predictive value of oocyte and embryo morphology criteria].

    Science.gov (United States)

    Figueira, Rita de Cássia Savio; Aoki, Tsutomu; Borges Junior, Edson

    2015-11-01

    In order to increase the success rate of in vitro fertilization cycles, several studies have focused on the identification of the embryo with higher implantation potential. Despite recent advances in the reproductive medicine, based on the OMICs technology, routinely applicable methodologies are still needed. Thus, in most fertilization centers embryo selection for transfer is still based on morphological parameters evaluated under light microscopy. Several morphological parameters may be evaluated, ranging from the pronuclear to blastocyst stage. In general, despite the day of transfer, some criteria are suggested to present a predictive value for embryo viability when analyzed independently or combined. However, the subjectivity of morphological evaluation, as well as the wide diversity of embryo classification systems used by different fertilization centers shows contrasting results, making the implementation of a consensus regarding different morphological criteria and their predictive value a difficult task. The optimization of embryo selection represents a large potential to increase treatment success rates, allowing the transfer of a reduced number of embryos and minimizing the risks of multiple pregnancy.

  7. The effect of follicle size and homogeneity of follicular development on the morphokinetics of human embryos.

    Science.gov (United States)

    Kahraman, Semra; Cetinkaya, Caroline Pirkevi; Cetinkaya, Murat; Yelke, Hakan; Colakoglu, Yesim Kumtepe; Aygun, Melih; Montag, Markus

    2017-07-01

    Our aim was to investigate follicular size (large, ≥17 mm and small, development (homogenous development: follicles being present in a homogenous spread of all sizes; heterogeneous: a predominance of small and large follicles) by analysing the morphokinetics of embryo development. In this prospective cohort study, 2526 COCs belonging to 187 patients were cultured to day 5. Embryos were evaluated morphokinetically. Four subgroups were defined: large follicles from heterogeneous cycles (LHet) and homogenous cycles (LHom) and small follicles from heterogeneous cycles (SHet) and homogenous cycles (SHom). Rates of fertilization, blastocyst formation and top and good quality blastocysts were found to be significantly higher in embryos from the LHom group (p Embryos from SHet had significantly more direct cleavages (p = 0.011). Time to reach blastocyst was shorter in SHom than LHet and LHom (p = 0.002; p = 0.027, respectively). However, once the blastocyst stage was achieved, implantation rates were not significantly different between subgroups, the highest rate being observed in the LHom group. Multivariable analysis revealed that homogeneity of follicular development and follicular size had a significant effect on blastocyst development and quality (p = 0.049; p development, influence early human embryo development. Patterns of follicular growth have an impact on embryo quality and viability which is reflected in morphokinetic variables.

  8. Rapid assimilation of yolk enhances growth and development of lizard embryos from a cold environment.

    Science.gov (United States)

    Storm, Melissa A; Angilletta, Michael J

    2007-10-01

    Selection for rapid growth and development in cold environments results in a geographic pattern known as countergradient variation. The eastern fence lizard, Sceloporus undulatus, exhibits countergradient variation in embryonic growth and development along latitudinal clines. To identify the proximate causes of countergradient variation, we compared the energy budgets of embryos from a cold environment (Virginia) and a warm environment (South Carolina) during development at a realistic thermal cycle. The difference in mean egg size between populations was controlled by removing yolk from large eggs and performing a sham manipulation on other eggs. Respiration was measured every 4 days throughout 48 days of incubation. After this period, eggs were dissected and the energy contents of embryos and yolk were determined by calorimetry. As expected from previous experiments, embryos from Virginia reached a more advanced stage of development and deposited more energy within tissues than embryos from South Carolina. The greater absorption of yolk by embryos from Virginia was associated with a higher rate of respiration. Assimilation of yolk by rapidly growing embryos could reduce growth or survival after hatching. Such costs might explain the maintenance of countergradient variation in S. undulatus.

  9. Changes in RNA Splicing in Developing Soybean (Glycine max Embryos

    Directory of Open Access Journals (Sweden)

    Delasa Aghamirzaie

    2013-11-01

    Full Text Available Developing soybean seeds accumulate oils, proteins, and carbohydrates that are used as oxidizable substrates providing metabolic precursors and energy during seed germination. The accumulation of these storage compounds in developing seeds is highly regulated at multiple levels, including at transcriptional and post-transcriptional regulation. RNA sequencing was used to provide comprehensive information about transcriptional and post-transcriptional events that take place in developing soybean embryos. Bioinformatics analyses lead to the identification of different classes of alternatively spliced isoforms and corresponding changes in their levels on a global scale during soybean embryo development. Alternative splicing was associated with transcripts involved in various metabolic and developmental processes, including central carbon and nitrogen metabolism, induction of maturation and dormancy, and splicing itself. Detailed examination of selected RNA isoforms revealed alterations in individual domains that could result in changes in subcellular localization of the resulting proteins, protein-protein and enzyme-substrate interactions, and regulation of protein activities. Different isoforms may play an important role in regulating developmental and metabolic processes occurring at different stages in developing oilseed embryos.

  10. Progressive hypoxia decouples activity and aerobic performance of skate embryos

    Science.gov (United States)

    Di Santo, Valentina; Tran, Anna H.; Svendsen, Jon C.

    2016-01-01

    Although fish population size is strongly affected by survival during embryonic stages, our understanding of physiological responses to environmental stressors is based primarily on studies of post-hatch fishes. Embryonic responses to acute exposure to changes in abiotic conditions, including increase in hypoxia, could be particularly important in species exhibiting long developmental time, as embryos are unable to select a different environment behaviourally. Given that oxygen is key to metabolic processes in fishes and aquatic hypoxia is becoming more severe and frequent worldwide, organisms are expected to reduce their aerobic performance. Here, we examined the metabolic and behavioural responses of embryos of a benthic elasmobranch fish, the little skate (Leucoraja erinacea), to acute progressive hypoxia, by measuring oxygen consumption and movement (tail-beat) rates inside the egg case. Oxygen consumption rates were not significantly affected by ambient oxygen levels until reaching 45% air saturation (critical oxygen saturation, Scrit). Below Scrit, oxygen consumption rates declined rapidly, revealing an oxygen conformity response. Surprisingly, we observed a decoupling of aerobic performance and activity, as tail-beat rates increased, rather than matching the declining metabolic rates, at air saturation levels of 55% and below. These results suggest a significantly divergent response at the physiological and behavioural levels. While skate embryos depressed their metabolic rates in response to progressive hypoxia, they increased water circulation inside the egg case, presumably to restore normoxic conditions, until activity ceased abruptly around 9.8% air saturation. PMID:27293746

  11. Expression pattern of glucose metabolism genes correlate with development rate of buffalo oocytes and embryos in vitro under low oxygen condition.

    Science.gov (United States)

    Kumar, Parveen; Verma, Arpana; Kumar, Manish; De, Sachinandan; Kumar, Rakesh; Datta, Tirtha Kumar

    2015-03-01

    This study evaluates the effect of low oxygen conditions (5 Vs 20%) on buffalo embryo development. Expression patterns of key glucose metabolism genes (HK, PFK, LDH, PDH, G6PDH and Glut1) were assessed in buffalo oocytes and embryos cultured at 5 and 20% oxygen and correlated with development rate. Maturation rate was observed by determining MII stages by Aceto-orcein method and blastocyst formation was observed at 7 day post insemination (dpi). Expression levels of genes were determined by real time PCR in oocytes / embryos at 5 and 20% O2. Oocyte maturation and blastocyst formation rates were significantly higher at 5% O2 as compared to 20% O2 (P embryos under 5% O2 tend to follow anaerobic glycolysis and pentose phosphate pathways to support optimum embryo development. Under 20% O2, oocytes and embryos had high expression of PDH indicating higher oxidative phosphorylation. Further, less G6PDH expression at 20% O2 was indicative of lower pentose phosphate activity. Higher expression of LDH was observed in oocytes and embryos under 20% O2 indicating sub-optimal culture conditions. High Glut1 activity was observed in the oocytes / embryos at 5% O2, indicative of high glucose uptake correlating with high expression of glycolytic genes. The expression patterns of glucose metabolism genes could be a valuable indicator of the development potential of oocytes and embryos. The study indicates the importance of reduced oxygen conditions for production of good quality embryos.

  12. Post-implantation mortality of in vitro produced embryos is associated with DNA methyltransferase 1 dysfunction in sheep placenta.

    Science.gov (United States)

    Ptak, Grazyna Ewa; D'Agostino, Antonella; Toschi, Paola; Fidanza, Antonella; Zacchini, Federica; Czernik, Marta; Monaco, Federica; Loi, Pasqualino

    2013-02-01

    Is DNA methyltransferase 1 (DNMT1) dysfunction involved in epigenetic deregulation of placentae from embryos obtained by assisted reproduction technologies (ARTs)? DNMT1 expression in growing placentae of in vitro produced (IVP) embryos is compromised and associated with pregnancy loss. DNMT1 maintains the methylation profile of genes during cell division. The methylation status of genes involved in placenta development is altered in embryos obtained in vitro. Disturbances in the epigenetic regulation of gene expression during placentogenesis could be involved in the frequent developmental arrest and loss of IVP embryos. Forty sheep were naturally mated (Group 1, CTR). IVP blastocysts (2-4 per ewe) were surgically transferred to the remaining 46 recipient sheep 6 days after oestrus (Group 2). Twenty-one recipients from Group 1 and 27 recipients from Group 2 were allowed to deliver in order to compare embryo survival in both groups at term (150 days). From the remaining recipients (n = 38), fetuses and placentae of both groups were recovered by paramedian laparotomy at Days 20, 22, 24, 26 and 28 of gestation. Immediately after collection, early placental tissues (chorion-allantois) were snap frozen in liquid nitrogen and DNMT1 expression and activity was evaluated. mRNA levels (for DNMT1, HDAC2, PCNA, DMAP1, MEST, IGF2, CDKN1C, H19) and the methylation status of H19 were also analyzed. Furthermore, embryo size and survival rate were measured. Our study shows that DNMT1 expression was reduced in early placentae from sheep IVP embryos. This reduction was associated with growth arrest and subsequent death of the sheep embryos. Conversely, normal levels of DNMT1 and its cofactors were observed in placentae from IVP embryos that survived this developmental bottleneck. Although DNA methylation machinery was severely compromised in IVP placentae only up to Day 24, the low DNMT1 enzymatic activity that persisted after this stage in IVP placentae was not lethal for the

  13. Quantitative analysis of mitochondrial RNA in goat-sheep cloned embryos.

    Science.gov (United States)

    Ma, Li-Bing; Yang, Li; Zhang, Yong; Cao, Jun-Wei; Hua, Song; Li, Ji-Xia

    2008-01-01

    Mitochondria are the key generators of cellular ATP, and contain extranuclear genome-mitochondrial DNA (mtDNA). In the process of nuclear transfer (NT), heteroplasmic sources of mtDNA from a donor cell and a recipient oocyte are mixed in the cytoplasm of the reconstituted embryo. Previous studies showed inconsistent patterns of mtDNA inheritance in offspring and early fetuses generated through interspecies NT. The quantitative analysis of mitochondrial RNA (mtRNA) in interspecies cloned embryos is useful for better understanding the fate of two types of mitochondria. The components of nicotinamide adenine dinucleotide (NADH) dehydrogenase were coded by both nuclear DNA (nDNA) and mtDNA. The Subunit 1 (ND-1) is one of seven NADH dehydrogenase subunits coded by mtDNA. In present study, using real-time and reverse-transcription PCR, the copy number of species-specific ND-1 mRNA was examined in goat-sheep cloned embryos of various developmental stages, and was applied to evaluate the expression pattern of species-specific mtDNA. The results of showed that (1) the expression of mtDNA derived from goat fetal fibroblast (GFF) decreased from 1-cell stage (immediately after fused) to 2-cell stage, and could not be detected from 4-cell stage onward to blastocyst stage; (2) the expression of mtDNA derived from sheep oocyte was roughly constant from 1-cell stage to the 8-cell stage, increased gradually from 16-cell stage, and sharply at morula and blastocyst stage. Moreover, we strongly argued a mechanism, that is GFF-derived mitochondria were degraded for the depression of bioenergetic functions, and then selectively eliminated during the embryogenesis of goat-sheep cloned embryos. (c) 2007 Wiley-Liss, Inc.

  14. Use of methanol as cryoprotectant and its effect on sox genes and proteins in chilled zebrafish embryos.

    Science.gov (United States)

    Desai, Kunjan; Spikings, Emma; Zhang, Tiantian

    2015-08-01

    Methanol is a widely used cryoprotectant (CPA) in cryopreservation of fish embryos, however little is known about its effect at the molecular level. This study investigated the effect of methanol on sox gene and protein expression in zebrafish embryos (50% epiboly) when they were chilled for 3 h and subsequently warmed and cultured to the hatching stages. Initial experiments were carried out to evaluate the chilling tolerance of 50% epiboly embryos which showed no significant differences in hatching rates for up to 6 h chilling in methanol (0.2-, 0.5- and 1 M). Subsequent experiments in embryos that had been chilled for 3 h in 1 M methanol and warmed and cultured up to the hatching stages found that sox2 and sox3 gene expression were increased significantly in hatched embryos that had been chilled compared to non-chilled controls. Sox19a gene expression also remained above control levels in the chilled embryos at all developmental stages tested. Whilst stable sox2 protein expression was observed between non-chilled controls and embryos chilled for 3 h with or without MeOH, a surge in sox19a protein expression was observed in embryos chilled for 3 h in the presence of 1 M MeOH compared to non-chilled controls and then returned to control levels by the hatching stage. The protective effect of MeOH was increased with increasing concentrations. Effect of methanol at molecular level during chilling was reported here first time which could add new parameter in selection of cryoprotectant while designing cryopreservation protocol. Copyright © 2015. Published by Elsevier Inc.

  15. Generation of transgenic Hydra by embryo microinjection.

    Science.gov (United States)

    Juliano, Celina E; Lin, Haifan; Steele, Robert E

    2014-09-11

    As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology(1). Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost.

  16. Embryo forming cells in carrot suspension cultures

    NARCIS (Netherlands)

    Toonen, M.A.J.

    1997-01-01


    Somatic cells of many plant species can be cultured in vitro and induced to form embryos that are able to develop into mature plants. This process, termed somatic embryogenesis, was originally described in carrot (Daucus carota L.). Somatic embryos develop through the same characteristic

  17. Human stem cell ethics: beyond the embryo.

    Science.gov (United States)

    Sugarman, Jeremy

    2008-06-05

    Human embryonic stem cell research has elicited powerful debates about the morality of destroying human embryos. However, there are important ethical issues related to stem cell research that are unrelated to embryo destruction. These include particular issues involving different types of cells used, the procurement of such cells, in vivo use of stem cells, intellectual property, and conflicts of interest.

  18. Embryo transfer using cryopreserved Boer goat blastocysts ...

    African Journals Online (AJOL)

    The aim of this trial was to evaluate the effect of embryo cryopreservation techniques on the survivability of embryos and fertility following transfer to Boer goat does. The oestrous cycles of 27 mature recipients Boer goat does were synchronised using controlled internal drug release dispensers (CIDR's) for 16 days. At CIDR ...

  19. Factors affecting the gene expression of in vitro cultured human preimplantation embryos

    NARCIS (Netherlands)

    Mantikou, E.; Jonker, M. J.; Wong, K. M.; van Montfoort, A. P. A.; de Jong, M.; Breit, T. M.; Repping, S.; Mastenbroek, S.

    2016-01-01

    What is the relative effect of common environmental and biological factors on transcriptome changes during human preimplantation development? Developmental stage and maternal age had a larger effect on the global gene expression profile of human preimplantation embryos than the culture medium or

  20. Effect of abscisic acid on the linoleic acid metabolism in developing maize embryos

    Energy Technology Data Exchange (ETDEWEB)

    Abian, J.; Gelpi, E.; Pages, M. (Centro de Investigacion y Desarrollo, Barcelona (Spain))

    1991-04-01

    Partially purified protein extracts from maize (Zea mays L.) embryos, whether treated or not with abscisic acid (ABA), were incubated with linoleic acid (LA) and 1-({sup 14}C)LA. The resulting LA metabolites were monitored by high performance liquid chromatography with a radioactivity detector and identified by gas chromatography-mass spectrometry. {alpha}- and {gamma}-ketol metabolites arising from 9-lipoxygenase activity were the more abundant compounds detected in the incubates, although the corresponding metabolites produced by 13-lipoxygenase were also present in the samples. In addition, a group of stereoisomers originating form two isomeric trihydroxy acids (9,12,13-trihydroxy-10-octadecenoic and 9,10,13-trihydroxy-11-octadecenoic acids) are described. Important variations in the relative proportions of the LA metabolites were observed depending on the embryo developmental stage and on ABA treatment. Two new ABA-induced compounds have been detected. These compounds are present in embryos at all developmental stages, being more abundant in old (60 days) embryos. Furthermore, ABA induction of these compounds is maximum at very young development stages, decreasing as maturation progresses. A tentative structure for these compounds (10-oxo-9,13-dihydroxy-11-octadecenoic acid and 12-oxo-9,13-dihydroxy-10-octadecenoic acid) is also provided. This study revealed an early stage in maize embryogenesis characterized by a higher relative sensitivity to ABA. The physiological importance of ABA on LA metabolism is discussed.

  1. Effect of Pelargonidin isolated from Ficus benghalensis L. on phenotypic changes in zebrafish (Danio rerio embryos

    Directory of Open Access Journals (Sweden)

    Uday Kundap

    2017-02-01

    Based on the results obtained, we infer that Pelargonidin can exhibit phenotypic anti-angiogenic variations in embryonic stage of fish embryos and it can be applied in future for exploration of its anti-angiogenic potential. Furthermore, Pelargonidin could serve as a candidate drug for in vivo inhibition of angiogenesis and can be applied for the treatment of neovascular diseases and tumor.

  2. The chicken embryo and its micro environment during egg storage and early incubation

    NARCIS (Netherlands)

    Reijrink, I.A.M.; Meijerhof, R.; Kemp, B.; Brand, van den H.

    2008-01-01

    When egg storage periods are prolonged (>7 days), hatchability and chick quality declines. The reason for this decline has been investigated, but is still not completely understood. At oviposition the developmental stage of the chicken embryo varies and so do the total number of viable cells.

  3. A technique for sexing fully developed embryos and early-instar larvae of the gypsy moth

    Science.gov (United States)

    Gilbert Levesque

    1963-01-01

    Because variation in sex ratio is an important factor in the population dynamics of the gypsy moth (Porthetria dispar), it is necessary to have some means of determining the ratio of males to females in a population at the beginning of the larval period as well as in the later stages. For determining the sex of fully developed embryos and early-...

  4. Morphometric and autoradiographic analysis of frontonasal development in the chick embryo

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, S.B.; Minkoff, R.

    1985-05-01

    Dimensional changes in the nasal processes were measured in chick embryos from Hamburger and Hamilton (1951) stages 20 through 27.5. Transverse measurements in the frontonasal region of freshly fixed embryos were compared to frontal sections of the nasal region of comparably staged embryos. These observations were correlated with autoradiographic studies of cell movement employing an implant labeling technique. Morphometric analysis indicated that between stages 20 and 25 the separation of the nasal pit orifices increased coincidentally with rapid forebrain enlargement. Since the separation of the nasal pit fundi increased more rapidly, the orientation of the nasal pits changed. Autoradiographic studies indicated that lateral movement of medial nasal process mesenchyme into the base of the nasal groove and medial area at the base of the lateral nasal process had occurred. After stage 25, the separation of the nasal orifices declined dramatically, coincidental with rapid orbital enlargement. In contrast, the separation of the nasal pit fundi was maintained. It is proposed that nasal development of the chick embryo may be governed initially by forebrain enlargement and associated lateral movements of mesenchyme in the medial nasal processes, resulting in reorientation of the invaginating nasal placodes; subsequently, orbital enlargement and an associated medial redirection of growth of the lateral nasal processes assumes greater significance to the continued development of the frontonasal region.

  5. Acute toxicity of chlorpyrifos to embryo and larvae of banded gourami Trichogaster fasciata

    NARCIS (Netherlands)

    Sumon, Kizar Ahmed; Saha, Sampa; Brink, van den Paul J.; Peeters, Edwin T.H.M.; Bosma, Roel H.; Rashid, Harunur

    2017-01-01

    This study elucidated the acute toxicity of chlorpyrifos on the early life stages of banded gourami (Trichogaster fasciata). To determine the acute effects of chlorpyrifos on their survival and development, we exposedthe embryos and two-day-old larvae to six concentrations (0, 0.01, 0.10, 1.0, 10

  6. Noninvasive metabolomic profiling as an adjunct to morphology for noninvasive embryo assessment in women undergoing single embryo transfer

    NARCIS (Netherlands)

    Seli, E.; Vergouw, C.G.; Morita, H.; Botros, L.; Roos, P.; Lambalk, C.B.; Yamashita, N.; Kato, O.; Sakkas, D.

    2010-01-01

    Objective: To determine whether metabolomic profiling of spent embryo culture media correlates with reproductive potential of human embryos. Design: Retrospective study. Setting: Academic and a private assisted reproductive technology (ART) programs. Patient(s): Women undergoing single embryo

  7. Regulation of membrane fusion and secretory events in the sea urchin embryo

    Energy Technology Data Exchange (ETDEWEB)

    Roe, J.L.

    1990-01-01

    Membrane fusion and secretory events play a key role in fertilization and early development in the sea urchin embryo. To investigate the mechanism of membrane fusion, the effect of inhibitors of metalloendoprotease activity was studied on two model systems of cell fusion; fertilization and spiculogenesis by primary mesenchyme cells in the embryo. Both the zinc chelator, 1,10-phenanthroline, and peptide metalloprotease substrates were found to inhibit both fertilization and gamete fusion, while peptides that are not substrates of metalloproteases did not affect either process. Primary mesenchyme cells form the larval skeleton in the embryo by deposition of mineral and an organic matrix into a syncytial cavity formed by fusion of filopodia of these cells. Metalloprotease inhibitors were found to inhibit spiculogenesis both in vivo and in cultures of isolated primary mesenchyme cells, and the activity of a metalloprotease of the appropriate specificity was found in the primary mesenchyme cells. These two studies implicate the activity of a metalloprotease in a necessary step in membrane fusion. Following fertilization, exocytosis of the cortical granules results in the formation of the fertilization envelope and the hyaline layer, that surround the developing embryo. The hatching enzyme is secreted by the blastula stage sea urchin embryo, which proteolyzes the fertilization envelope surrounding the embryo, allowing the embryo to hatch. Using an assay that measures {sup 125}I-fertilization envelope degradation, the hatching enzyme was identified as a 33 kDa metalloprotease, and was purified by ion-exchange and affinity chromatography from the hatching media of Strongylocentrotus purpuratus embryos. The hatching enzyme showed a substrate preference for only a minor subset of fertilization envelope proteins.

  8. Tiger, Bengal and Domestic Cat Embryos Produced by Homospecific and Interspecific Zona-Free Nuclear Transfer.

    Science.gov (United States)

    Moro, L N; Jarazo, J; Buemo, C; Hiriart, M I; Sestelo, A; Salamone, D F

    2015-10-01

    The aim of this study was to evaluate three different cloning strategies in the domestic cat (Felis silvestris) and to use the most efficient to generate wild felid embryos by interspecific cloning (iSCNT) using Bengal (a hybrid formed by the cross of Felis silvestris and Prionailurus bengalensis) and tiger (Panthera tigris) donor cells. In experiment 1, zona-free (ZP-free) cloning resulted in higher fusion and expanded blastocyst rates with respect to zona included cloning techniques that involved fusion or injection of the donor cell. In experiment 2, ZP-free iSCNT and embryo aggregation (2X) were assessed. Division velocity and blastocyst rates were increased by embryo aggregation in the three species. Despite fewer tiger embryos than Bengal and cat embryos reached the blastocyst stage, Tiger 2X group increased the percentage of blastocysts with respect to Tiger 1X group (3.2% vs 12.1%, respectively). Moreover, blastocyst cell number was almost duplicated in aggregated embryos with respect to non-aggregated ones within Bengal and tiger groups (278.3 ± 61.9 vs 516.8 ± 103.6 for Bengal 1X and Bengal 2X groups, respectively; 41 vs 220 ± 60 for Tiger 1X and Tiger 2X groups, respectively). OCT4 analysis also revealed that tiger blastocysts had higher proportion of OCT4-positive cells with respect to Bengal blastocysts and cat intracytoplasmic sperm injection blastocysts. In conclusion, ZP-free cloning has improved the quality of cat embryos with respect to the other cloning techniques evaluated and was successfully applied in iSCNT complemented with embryo aggregation. © 2015 Blackwell Verlag GmbH.

  9. Inhibition of dye-coupling in Patella (mollusca) embryos by microinjection of antiserum against Nephrops (arthropoda) gap junctions

    NARCIS (Netherlands)

    Serras, F.; Buultjens, T.E.J.; Finbow, M.E.

    1988-01-01

    Antiserum raised against Nephrops gap junctions was injected into single cells of the 2-, 4-, 8-, 16-, and 32-cell stage of the Patella vulgata embryos. The pattern of junctional communication by iontophoresis of Lucifer Yellow CH was tested at the 32-cell stage. The results show that the normal

  10. Pre-hatching embryo-dependent and -independent programming of endometrial function in cattle.

    Directory of Open Access Journals (Sweden)

    Mariana Sponchiado

    Full Text Available The bovine pre-implantation embryo secretes bioactive molecules from early development stages, but effects on endometrial function are reported to start only after elongation. Here, we interrogated spatially defined regions of the endometrium transcriptome for responses to a day 7 embryo in vivo. We hypothesize that exposure to an embryo changes the abundance of specific transcripts in the cranial region of the pregnant uterine horn. Endometrium was collected from the uterotubal junction (UTJ, anterior (IA, medial (IM and posterior (IP regions of the uterine horn ipsilateral to the CL 7 days after estrus from sham-inseminated (Con or artificially inseminated, confirmed pregnant (Preg cows. Abundance of 86 transcripts was evaluated by qPCR using a microfluidic platform. Abundance of 12 transcripts was modulated in the Preg endometrium, including classical interferon-stimulated genes (ISG15, MX1, MX2 and OAS1Y, prostaglandin biosynthesis genes (PTGES, HPGD and AKR1C4, water channel (AQP4 and a solute transporter (SLC1A4 and this was in the UTJ and IA mainly. Additionally, for 71 transcripts, abundance varied according to region of the reproductive tract. Regulation included downregulation of genes associated with proliferation (IGF1, IGF2, IGF1R and IGF2R and extracellular matrix remodeling (MMP14, MMP19 and MMP2 and upregulation of anti-adhesive genes (MUC1 in the cranial regions of uterine horn. Physical proximity to the embryo provides paracrine regulation of endometrial function. Embryo-independent regulation of the endometrial transcriptome may support subsequent stages of embryo development, such as elongation and implantation. We speculate that successful early embryo-dependent and -independent programming fine-tune endometrial functions that are important for maintenance of pregnancy in cattle.

  11. Pre-hatching embryo-dependent and -independent programming of endometrial function in cattle.

    Science.gov (United States)

    Sponchiado, Mariana; Gomes, Nathália Souza; Fontes, Patrícia Kubo; Martins, Thiago; Del Collado, Maite; Pastore, Athos de Assumpção; Pugliesi, Guilherme; Nogueira, Marcelo Fábio Gouveia; Binelli, Mario

    2017-01-01

    The bovine pre-implantation embryo secretes bioactive molecules from early development stages, but effects on endometrial function are reported to start only after elongation. Here, we interrogated spatially defined regions of the endometrium transcriptome for responses to a day 7 embryo in vivo. We hypothesize that exposure to an embryo changes the abundance of specific transcripts in the cranial region of the pregnant uterine horn. Endometrium was collected from the uterotubal junction (UTJ), anterior (IA), medial (IM) and posterior (IP) regions of the uterine horn ipsilateral to the CL 7 days after estrus from sham-inseminated (Con) or artificially inseminated, confirmed pregnant (Preg) cows. Abundance of 86 transcripts was evaluated by qPCR using a microfluidic platform. Abundance of 12 transcripts was modulated in the Preg endometrium, including classical interferon-stimulated genes (ISG15, MX1, MX2 and OAS1Y), prostaglandin biosynthesis genes (PTGES, HPGD and AKR1C4), water channel (AQP4) and a solute transporter (SLC1A4) and this was in the UTJ and IA mainly. Additionally, for 71 transcripts, abundance varied according to region of the reproductive tract. Regulation included downregulation of genes associated with proliferation (IGF1, IGF2, IGF1R and IGF2R) and extracellular matrix remodeling (MMP14, MMP19 and MMP2) and upregulation of anti-adhesive genes (MUC1) in the cranial regions of uterine horn. Physical proximity to the embryo provides paracrine regulation of endometrial function. Embryo-independent regulation of the endometrial transcriptome may support subsequent stages of embryo development, such as elongation and implantation. We speculate that successful early embryo-dependent and -independent programming fine-tune endometrial functions that are important for maintenance of pregnancy in cattle.

  12. OCT-4 expression is essential for the segregation of trophectoderm lineages in porcine preimplantation embryos.

    Science.gov (United States)

    Emura, Natsuko; Sakurai, Nobuyuki; Takahashi, Kazuki; Hashizume, Tsutomu; Sawai, Ken

    2016-08-25

    Oct-4, a member of the POU family of transcription factors, is a key factor that regulates the segregation of the inner cell mass (ICM) and the trophectoderm (TE) during the transition from morula to blastocyst in mice. However, little is known about its role in porcine early embryogenesis. To determine the function of OCT-4 in the ICM and TE segregation of porcine embryos, we studied the developmental morphology of porcine embryos using RNA interference technology. Our experiments demonstrated that when 1-cell stage embryos were co-injected with the small interfering RNA (siRNA)for targeted knockdown of OCT-4 (OCT-4-siRNA) and tetramethylrhodamine isothiocyanate (TRITC)-dextran conjugate (Dx), they failed to form blastocysts. Therefore, in this study, we constructed chimeric embryos comprising blastomeres that either expressed OCT-4 normally or showed downregulated OCT-4 expression by co-injection of OCT-4-siRNA and Dx into one blastomere in 2- to 4-cell stage embryos. In control embryos, which were co-injected with control siRNA and Dx, Dx-positive cells contributed to the TE lineage in almost all the blastocysts examined. In contrast, Dx-positive cells derived from a blastomere co-injected with OCT-4-siRNA and Dx were degenerated in almost half the blastocysts. This was probably due to the inability of these cells to differentiate into the TE lineage. Real-time RT-PCR analysis revealed no difference in the levels of SOX2, TEAD4, FGF4 and FGFR1-IIIc, all of which are known to be regulated by OCT-4, between the OCT-4-siRNA-injected morulae and the control ones. However, the level of CDX2, a molecule specifically expressed in the TE lineage, was significantly higher in the former than in the latter. Our results indicate that continuous expression of OCT-4 in blastomeres is essential for TE formation of porcine embryos.

  13. Micro-magnetic resonance imaging study of live quail embryos during embryonic development.

    Science.gov (United States)

    Duce, Suzanne; Morrison, Fiona; Welten, Monique; Baggott, Glenn; Tickle, Cheryll

    2011-01-01

    Eggs containing live Japanese quail embryos were imaged using micro-magnetic resonance imaging (μMRI) at 24-h intervals from Day 0 to 8, the period during which the main body axis is being laid down and organogenesis is taking place. Considerable detail of non-embryonic structures such as the latebra was revealed at early stages but the embryo could only be visualized around Day 3. Three-dimensional (3D) changes in embryo length and volume were quantified and also changes in volume in the extra- and non-embryonic components. The embryo increased in length by 43% and nearly trebled in volume between Day 4 and Day 5. Although the amount of yolk remained fairly constant over the first 5 days, the amount of albumen decreases significantly and was replaced by extra-embryonic fluid (EEF). ¹H longitudinal (T₁) and transverse (T₂) relaxation times of different regions within the eggs were determined over the first 6 days of development. The T₂ measurements mirrored the changes in image intensity observed, which can be related to the aqueous protein concentrations. In addition, a comparison of the development of Day 0 to 3 quail embryos exposed to radiofrequency (rf) pulses, 7 T static magnetic fields and magnetic field gradients for an average of 7 h with the development of control embryos did not reveal any gross changes, thus confirming that μMRI is a suitable tool for following the development of live avian embryos over time from the earliest stages. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Fossilized embryos are widespread but the record is temporally and taxonomically biased

    Science.gov (United States)

    Donoghue, P.C.J.; Kouchinsky, A.; Waloszek, Dieter; Bengtson, S.; Dong, X.-P.; Val'Kov, A.K.; Cunningham, J.A.; Repetski, J.E.

    2006-01-01

    We report new discoveries of embryos and egg capsules from the Lower Cambrian of Siberia, Middle Cambrian of Australia and Lower Ordovician of North America. Together with existing records, embryos have now been recorded from four of the seven continents. However, the new discoveries highlight secular and systematic biases in the fossil record of embryonic stages. The temporal window within which the embryos and egg capsules are found is of relatively short duration; it ends in the Early Ordovician and is roughly coincident with that of typical "Orsten"-type faunas. The reduced occurrence of such fossils has been attributed to reducing levels of phosphate in marine waters during the early Paleozoic, but may also be owing to the increasing depth of sediment mixing by infaunal metazoans. Furthermore, most records younger than the earliest Cambrian are of a single kind - large eggs and embryos of the priapulid-like scalidophoran Markuelia. We explore alternative explanations for the low taxonomic diversity of embryos recovered thus far, including sampling, size, anatomy, ecology, and environment, concluding that the preponderance of Markuelia embryos is due to its precocious development of cuticle at an embryonic stage, predisposing it to preservation through action as a substrate on which microbially mediated precipitation of authigenic calcium phosphate may occur. The fossil record of embryos may be limited to a late Neoproterozoic to early Ordovician snapshot that is subject to dramatic systematic bias. Together, these biases must be considered seriously in attempts to use the fossil record to arbitrate between hypotheses of developmental and life history evolution implicated in the origin of metazoan clades. ?? 2006 Blackwell Publishing Ltd.

  15. Single-site neural tube closure in human embryos revisited.

    Science.gov (United States)

    de Bakker, Bernadette S; Driessen, Stan; Boukens, Bastiaan J D; van den Hoff, Maurice J B; Oostra, Roelof-Jan

    2017-10-01

    Since the multi-site closure theory was first proposed in 1991 as explanation for the preferential localizations of neural tube defects, the closure of the neural tube has been debated. Although the multi-site closure theory is much cited in clinical literature, single-site closure is most apparent in literature concerning embryology. Inspired by Victor Hamburgers (1900-2001) statement that "our real teacher has been and still is the embryo, who is, incidentally, the only teacher who is always right", we decided to critically review both theories of neural tube closure. To verify the theories of closure, we studied serial histological sections of 10 mouse embryos between 8.5 and 9.5 days of gestation and 18 human embryos of the Carnegie collection between Carnegie stage 9 (19-21 days) and 13 (28-32 days). Neural tube closure was histologically defined by the neuroepithelial remodeling of the two adjoining neural fold tips in the midline. We did not observe multiple fusion sites in neither mouse nor human embryos. A meta-analysis of case reports on neural tube defects showed that defects can occur at any level of the neural axis. Our data indicate that the human neural tube fuses at a single site and, therefore, we propose to reinstate the single-site closure theory for neural tube closure. We showed that neural tube defects are not restricted to a specific location, thereby refuting the reasoning underlying the multi-site closure theory. Clin. Anat. 30:988-999, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. A novel embryo culture media supplement that improves pregnancy rates in mice.

    Science.gov (United States)

    Highet, A R; Bianco-Miotto, T; Pringle, K G; Peura, A; Bent, S; Zhang, J; Nottle, M B; Thompson, J G; Roberts, C T

    2017-03-01

    The preimplantation embryo in vivo is exposed to numerous growth factors in the female reproductive tract, which are not recapitulated in embryo culture media in vitro The IGF2 and plasminogen activator systems facilitate blastocyst development. We hypothesized that the addition of IGF2 in combination with urokinase plasminogen activator (uPA) and plasminogen could improve rates of blastocyst hatching and implantation in mice. B6BcF1 and CBAB6F2 mouse embryos were divided into one of four supplemented culture media treatment groups: (1) control (media only); (2) 12.5 nM IGF2; (3) 10 µg/mL uPA and 5 µg/mL plasminogen; or (4) a combination of IGF2, uPA and plasminogen treatments. Embryo development to blastocyst stage and hatching were assessed before transfer to pseudopregnant recipient females and implantation, pregnancy rates and postnatal growth were assessed. After 90.5 h of culture, IGF2 + U + P treatment increased the percentage of B6BcF1 embryos that were hatching/hatched and percentage developing to blastocyst stage compared with controls (P culture, IGF2, uPA and plasminogen supplementation of culture media can improve pregnancy success, but the effect of treatment is dependent on the mouse strain. © 2017 Society for Reproduction and Fertility.

  17. Actomyosin polarisation through PLC-PKC triggers symmetry breaking of the mouse embryo.

    Science.gov (United States)

    Zhu, Meng; Leung, Chuen Yan; Shahbazi, Marta N; Zernicka-Goetz, Magdalena

    2017-10-13

    Establishment of cell polarity in the mammalian embryo is fundamental for the first cell fate decision that sets aside progenitor cells for both the new organism and the placenta. Yet the sequence of events and molecular mechanism that trigger this process remain unknown. Here, we show that de novo polarisation of the mouse embryo occurs in two distinct phases at the 8-cell stage. In the first phase, an apical actomyosin network is formed. This is a pre-requisite for the second phase, in which the Par complex localises to the apical domain, excluding actomyosin and forming a mature apical cap. Using a variety of approaches, we also show that phospholipase C-mediated PIP 2 hydrolysis is necessary and sufficient to trigger the polarisation of actomyosin through the Rho-mediated recruitment of myosin II to the apical cortex. Together, these results reveal the molecular framework that triggers de novo polarisation of the mouse embryo.The molecular trigger that establishes cell polarity in the mammalian embryo is unclear. Here, the authors show that de novo polarisation of the mouse embryo at the 8-cell stage is directed by Phospholipase C and Protein kinase C and occurs in two phases: polarisation of actomyosin followed by the Par complex.

  18. Nucleolar remodeling in nuclear transfer embryos

    DEFF Research Database (Denmark)

    Laurincik, Jozef; Maddox-Hyttel, Poul

    2007-01-01

    the developmental potential of embryos originating from varied nuclear transfer protocols. In bovine in vivo developed embryos, functional ribosome-synthesizing nucleoli become structurally distinct toward the end of the 4th post-fertilization cell cycle. In embryonic cell nuclear transfer embryos, fully developed...... to develop fully functional nucleoli. In bovine in vivo developed embryos, a range of important nucleolar proteins (e.g., topoisomerase I, upstream binding factor and RNA polymerase I, fibrillarin, nucleophosmin and nucleolin) become localized to the nucleolar anlage over several cell cycles. This relocation......Transcription of the ribosomal RNA (rRNA) genes occurs in the nucleolus and results in ribosome biogenesis. The rRNA gene activation and the associated nucleolus formation may be used as a marker for the activation of the embryonic genome in mammalian embryos and, thus serve to evaluate...

  19. Embryo transfer in domestic South American camelids.

    Science.gov (United States)

    Sumar, Julio B

    2013-01-10

    Intraspecific and interspecific embryo transfer in domestic South American camelids is developing into a well-established technique. Reports reveal many benefits of using reproductive biotechnologies to allow rapid propagation of alpacas and llamas of high genetic merit (e.g., high fiber quality, preserve color variation). The objective of this review is to provide up-to-date information about embryo transfer in domestic South American camelids. Specific information is provided on criteria for male selection, donor and recipient synchronization, the practice of single- vs. super-ovulation protocols, embryo recovery and transfer techniques, advances in cryopreservation of embryos, results of intra- and inter-specific transfer, and the future of the embryo transfer in domestic South American camelids. Copyright © 2012. Published by Elsevier B.V.

  20. Feel, smell and see in an egg: emergence of perception and learning in an immature invertebrate, the cuttlefish embryo.

    Science.gov (United States)

    Romagny, Sébastien; Darmaillacq, Anne-Sophie; Guibé, Mathieu; Bellanger, Cécile; Dickel, Ludovic

    2012-12-01

    It is now well established that prenatal sensory experience affects development itself and has long-term consequences in terms of postnatal behavior. This study focused on the functionality of the sensory system in cuttlefish in ovo. Embryos of stage 23, 25 and 30 received a tactile, chemical or visual stimulus. An increase of mantle contraction rhythm was taken to indicate a behavioral response to the stimulus. We clearly demonstrated that tactile and chemical systems are functional from stage 23, whereas the visual system is functional only from stage 25. At stage 25 and 30, embryos were also exposed to a repeated light stimulus. Stage 30 embryos were capable of habituation, showing a progressive decrease in contractions across stimulations. This process was not due to fatigue as we observed response recovery after a dishabituation tactile stimulus. This study is the first to show that cuttlefish embryos behaviorally respond to stimuli of different modalities and that the visual system is the last to become functional during embryonic development, as in vertebrate embryos. It also provides new evidence that the memory system develops in ovo in cuttlefish.

  1. Potential of human twin embryos generated by embryo splitting in assisted reproduction and research.

    Science.gov (United States)

    Noli, Laila; Ogilvie, Caroline; Khalaf, Yacoub; Ilic, Dusko

    2017-03-01

    Embryo splitting or twinning has been widely used in veterinary medicine over 20 years to generate monozygotic twins with desirable genetic characteristics. The first human embryo splitting, reported in 1993, triggered fierce ethical debate on human embryo cloning. Since Dolly the sheep was born in 1997, the international community has acknowledged the complexity of the moral arguments related to this research and has expressed concerns about the potential for reproductive cloning in humans. A number of countries have formulated bans either through laws, decrees or official statements. However, in general, these laws specifically define cloning as an embryo that is generated via nuclear transfer (NT) and do not mention embryo splitting. Only the UK includes under cloning both embryo splitting and NT in the same legislation. On the contrary, the Ethics Committee of the American Society for Reproductive Medicine does not have a major ethical objection to transferring two or more artificially created embryos with the same genome with the aim of producing a single pregnancy, stating that 'since embryo splitting has the potential to improve the efficacy of IVF treatments for infertility, research to investigate the technique is ethically acceptable'. Embryo splitting has been introduced successfully to the veterinary medicine several decades ago and today is a part of standard practice. We present here an overview of embryo splitting experiments in humans and non-human primates and discuss the potential of this technology in assisted reproduction and research. A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies on embryo splitting in humans and non-human primates. 'Embryo splitting' and 'embryo twinning' were used as the keywords, alone or in combination with other search phrases relevant to the topics of biology of preimplantation embryos. A very limited number of studies have been conducted in humans and non

  2. [An ongoing twin pregnancy after embryo time laps monitoring in a patient with a history of IVF failures--case report and literature review].

    Science.gov (United States)

    Radwan, Paweł; Krasiński, Rafał; Radwan, Michał; Połać, Ireneusz

    2014-04-01

    A standard assessment of embryo morphology at given time points does not always allow to transfer the embryo with the highest implantation potential. The effect of transfer of an improper embryo results in a lack of pregnancy or a miscarriage and, as a consequence, exposes the patient to unnecessary emotional stress and necessity to perform yet another transfer of frozen embryos. We present a case of a patient with earlier IVF failures. The use of time-lapse technique in this case helped to choose two good embryos. The transfer resulted in ongoing twin pregnancy. A 35-year-old woman with history of IVF-ET treatment failure was deemed eligible for an ICSI procedure because of the male factor. Ovarian stimulation was performed according to the agonist long protocol. Eight MII oocytes were fertilized and seven embryos were obtained. Continuous embryo monitoring was performed with the use of Primo Vision system. Forty-four hours after fertilization only 2 correctly developing embryos were identified. They were transferred on day 3. The development of the remaining 5 embryos was arrested. These embryos did not achieve the blastocyst stage on day 5-6 after fertilization. Forty days after embryo transfer a twin pregnancy, confirmed with fetal heart rate of both fetuses, was revealed on ultrasound examination. Currently the patient is at 27 weeks of ongoing twin gestation. The system of continuous embryo monitoring introduces new criteria for the examination of embryo development. These new parameters can be useful in clinical practice. However prospective randomized studies are necessary to provide data confirming the usefulness of time-lapse technique in IVF treatment.