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Silva Jose J Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Cambridge CB2 1QR, UK. - - 2009
Pluripotency is generated naturally during mammalian development through formation of the epiblast, founder tissue of the embryo proper. Pluripotency can be recreated by somatic cell reprogramming. Here we present evidence that the homeodomain protein Nanog mediates acquisition of both embryonic and induced pluripotency. Production of pluripotent hybrids by cell fusion ...
Berman Seth D - - 2009
The retinoblastoma tumor-suppressor protein, pRb, is a member of the pocket protein family that includes p107 and p130. These proteins have well-defined roles in regulating entry into and exit from the cell cycle and also have cell cycle-independent roles in facilitating differentiation. Here we investigate the overlap between pocket protein's ...
Kobus Karoline - - 2009
Maternal ingestion of folic acid (FA) reduces neural tube defects, which are associated with high homocysteine levels. Present study evaluated the effects of FA and homocysteine on cell proliferation and cell adhesion, as well as on apoptosis, throughout the development of the spinal cord and mesenchyme of chicken embryos. Normal ...
Furuya Hidetaka - - 2009
A new species of dicyemid mesozoan is described from Opisthoteuthis depressa Iijima and Ikeda, 1895, collected from Suruga Bay in Japan. Dicyemennea umbraculum n. sp. is a medium species that reaches approximately 3500 microm in length. This species attaches to the surface of the renal appendages. The vermiform stages are ...
Hall Vanessa J - - 2009
The signaling mechanisms regulating pluripotency in porcine embryonic stem cells and embryos are unknown. In this study, we characterize cell signaling in the in-vivo porcine inner cell mass and later-stage epiblast. We evaluate expression of OCT4, NANOG, SOX2, genes within the JAK/STAT pathway (LIF, LIFR, GP130), FGF pathway (bFGF, FGFR1, ...
Viczian Andrea S - - 2009
Pluripotent cells such as embryonic stem (ES) and induced pluripotent stem (iPS) cells are the starting point from which to generate organ specific cell types. For example, converting pluripotent cells to retinal cells could provide an opportunity to treat retinal injuries and degenerations. In this study, we used an in ...
Higaki Shogo - - 2009
We investigated the feasibility of cryopreservation of zebrafish (Danio rerio) blastomeres and primordial germ cells (PGCs) by rapid freezing of dechorionated whole embryos at the blastula, gastrula and segmentation stages. Initially we examined the glass-forming properties and embryo toxicities of 5 cryoprotectants: methanol (MeOH), ethylene glycol (EG), dimethyl sulfoxide (DMSO), ...
Rielland Maite - - 2009
Development after nuclear transfer (NT) is subjected to defects originating from both the epiblast and the trophoblast parts of the conceptus and is always accompanied by placentomegaly at term. Here we have investigated the origin of the reprogramming errors affecting the trophoblast lineage in mouse NT embryos. We show that ...
Lyons Deirdre C DC Department of Molecular and Cell Biology, 385 Life Sciences Addition, University of California, Berkeley, CA 94720-3200, USA. - - 2009
The unequal division of the CD blastomere at second cleavage is critical in establishing the second embryonic axis in the leech Helobdella, as in other unequally cleaving spiralians. When CD divides, the larger D and smaller C blastomeres arise invariantly on the left and right sides of the embryo, respectively. ...
Tartia Alina P - - 2009
Fertilized mouse eggs regulate their size principally by accumulating glycine as an intracellular osmolyte using the GLYT1 (SLC6A9) transporter, a mechanism of cell volume homeostasis apparently unique to early embryos before the morula stage. However, nothing was known of cell volume regulation in oocytes before fertilization. We show here that ...
Nandedkar Pandit - - 2009
Parthenogenesis and Somatic cell nuclear transfer (SCNT) techniques, offer a unique approach to manipulate the genetic composition of derived human embryonic stem cells - an essential step if the full opportunities for disease modeling, drug discovery or individualized stem cell therapy are to be realized. The present study describes the ...
Ruzov Alexey A Human Genetics Unit, MRC, IGMM, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, - - 2009
Loss of the of the maintenance methyltransferase xDNMT1 during Xenopus development results in premature transcription and activation of a p53-dependent apoptotic program that accounts for embryo lethality. Here, we show that activation of the apoptotic response is signalled through the methyl-CpG binding protein xMBD4 and the mismatch repair pathway protein ...
Zernicka-Goetz Magdalena M The Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK. - - 2009
The preimplantation mammalian embryo offers a striking opportunity to address the question of how and why apparently identical cells take on separate fates. Two cell fate decisions are taken before the embryo implants; these decisions set apart a group of pluripotent cells, progenitors for the future body, from the distinct ...
Chen Ying - - 2009
Pyrrolizidine alkaloids (PAs) are well-known natural hepatotoxins distributed widely in thousands of plants in the world. Adonifoline (Adon), senecionine (Sene) and monocrotaline (Mono) are retronecine-type PAs, and the present study is designed to observe the effects of intracellular glutathione on toxicity of these three PAs in human normal liver L-02 ...
Sugimura S - - 2009
Interspecies somatic cell nucleus transfer (iSCNT) could be a useful bioassay system for assessing the ability of mammalian somatic cells to develop into embryos. To examine this possibility, we performed canine iSCNT using porcine oocytes, allowed to mature in vitro, as recipients. Canine fibroblasts from the tail tips and dewclaws ...
Oh H J - - 2009
The aim of this study was to investigate whether roscovitine (the cyclin-dependent kinase 2 inhibitor) effectively induces synchronization of the donor cell cycle at G0/G1 and to examine the effect of donor cell cycle synchronization protocols on canine somatic cell nucleus transfer. Canine fibroblasts were obtained from skin biopsy cultures ...
Cao Shanbo - - 2009
Authentic bovine embryonic stem (ES) cell lines have not been established despite progress made for more than two decades. Isolation and culture of primary ES cell colonies are the first critical step towards establishment of stable ES cell lines. Here we report a novel method designated as "Separate and Seed" ...
Brero Alessandro - - 2009
Following nuclear transfer (NT) the epigenetic state of a donor nucleus must be reprogrammed to an embryonic one. To evaluate the efficiency of nuclear reprogramming, we monitored the levels of histone H3 di/tri-methylated on lysine 4 (H3K4m2/3), a marker for transcriptionally active/permissive euchromatin, and of histone H3 tri-methylated on lysine ...
Furuya Hidetaka - - 2009
Two new species of dicyemid mesozoan are described from Sepia longipes, Sasaki, 1913, collected from Tosa Bay in Japan. Dicyema oxycephalum n. sp. is a medium-sized species that is about 1,800 microm in length. It lives in folds of the renal appendages. The vermiform stages are characterized as having 28-34 ...
Lai Dongmei - - 2009
Mouse and human embryonic stem (ES) cells are usually maintained in an undifferentiated state by coculture with mouse embryonic fibroblasts (MEFs) as feeder cells. In the case of mouse ES cells, addition of leukemia inhibitory factor (LIF) to culture media is also necessary to prevent cell differentiation. Here, we report ...
Cho Seong-Keun - - 2009
Acetylcholine (ACh) causes early activation events in mouse oocytes, but little is known about its precise role in the early embryonic development of mice. We aimed to determine whether and how ACh is capable of rescuing two-cell block in an in vitro culture system. ACh evoked different transient Ca(2+) patterns ...
Wühr Martin M Department of Systems Biology, Harvard Medical School, Boston, MA 02115, - - 2009
In animal cells, cytokinesis is mediated by the constriction of a cortical ring. In this issue, Carvalho et al. (2009) show in embryos of the worm Caenorhabditis elegans that the rate of ring constriction during cytokinesis is proportional to the initial cell perimeter, ensuring that the duration of cytokinesis is ...
Chen Yaoyao - - 2009
The molecular mechanisms that underlie the development of primitive myeloid cells in vertebrate embryos are not well understood. Here we characterize the role of cebpa during primitive myeloid cell development in Xenopus. We show that cebpa is one of the first known hematopoietic genes expressed in the embryo. Loss- and ...
Meilhac Sigolène M SM Gurdon Institute, University of Cambridge, - - 2009
In the mouse blastocyst, some cells of the inner cell mass (ICM) develop into primitive endoderm (PE) at the surface, while deeper cells form the epiblast. It remained unclear whether the position of cells determines their fate, such that gene expression is adjusted to cell position, or if cells are ...
Zama Kota - - 2009
We report here a method of simultaneously quantifying glucosylceramide (GlcCer) and galactosylceramide (GalCer) by normal-phase HPLC using O-phtalaldehyde derivatives. Treatment with sphingolipid ceramide N-deacylase which converts the cerebrosides in the sample to their lyso-forms was followed by the quantitative labeling of free NH(2) groups of the lyso-cerebrosides with O-phtalaldehyde. Using ...
Wang Shie - - 2009
The correlation between the early embryonic block to development and mitochondrial activity was investigated comparing two-cell embryos produced in vitro from Kunming (KM) and B6C3F1 mice. One-cell embryos were obtained from two species of hybrids (female KM mice mated with KM males and female B6C3F1 mice mated with KM males) ...
Wang, W.H.
Microinjection of DNA/mRNA/morpholinos is a critical technology for molecular biology and drug discovery. When dealing with suspended cells, state-of-the-art manual injection involves a time-consuming and tedious sample preparation procedure, to accurately align cells. To enable automatic microrobotic cell injection, this paper reports on two inexpensive, reusable, biocompatible, and easy-to-make devices ...
Kawamura Kazuhiro - - 2009
Successful implantation of the blastocyst and subsequent placental development is essential for reproduction. Expression of brain-derived neurotrophic factor (BDNF) and neurotrophin-4/5, together with their receptor, tyrosine kinase B (TrkB), in trophectoderm cells of blastocyst suggests their potential roles in implantation and placental development. Here we demonstrated that treatment with BDNF ...
Sano Chiaki - - 2009
Embryonic stem (ES) cells are characterized by pluripotency, in particular the ability to form a germline on injection into blastocysts. Despite numerous attempts, ES cell lines derived from rat embryos have not yet been established. The reason for this is unclear, although certain intrinsic biological differences among species and/or strains ...
Miki H - - 2009
Somatic cell cloning by nuclear transfer (NT) in mice is associated with hyperplastic placentas at term. To dissect the effects of embryonic and extraembryonic tissues on this clone-associated phenotype, we constructed diploid (2n) fused with (<-->) tetraploid (4n) chimeras from NT- and fertilization-derived (FD) embryos. Generally, the 4n cells contributed ...
Ogawa H - - 2009
Neither parthenogenetic (PG) nor androgenetic (AG) mouse embryos survive after day 9.5 of pregnancy, owing to the inadequate growth of extraembryonic tissues, including the placenta. At day 9.5 of pregnancy, the placental structures are poorly developed in PG embryos, while trophoblast giant cells are abundant at the implantation site in ...
Wenhui Wang, Darren Hewett, ...
This paper presents image processing algorithms recognising cell structures for an automated cell injection system. For suspended zebrafish embryos, the convex hull and convexity defects of the cytoplasm contour are used. For adherent endothelial cells, the surface and shadow information of the nucleoli is used. Overall, 550 zebrafish embryos were ...
Scheenen W J J M - - 2009
Transgenic animals are commonly employed to explore the function of individual proteins. Transgenic animal models include the mouse, the zebrafish, and the South African clawed toad Xenopus laevis. In contrast to mice and zebrafish, with Xenopus transgenesis DNA integration is mostly achieved in the one-cell stage. Moreover, Xenopus (as well ...
Weisblat David A - - 2009
One advantage of using Helobdella (leech) embryos as an experimental system is their amenability for microinjection. Blastomeres ranging in size from the zygote (400 microm diameter) down to micromeres and primary blast cells (approximately 20 microm diameter) can be injected by pressure under a dissecting microscope. Smaller cells can be ...
Yuri Shunsuke - - 2009
Sall4 is a mouse homolog of a causative gene of the autosomal dominant disorder Okihiro syndrome. We previously showed that the absence of Sall4 leads to lethality during peri-implantation and that Sall4-null embryonic stem (ES) cells proliferate poorly with intact pluripotency when cultured on feeder cells. Here, we report that, ...
Ketting René F - - 2009
MicroRNAs are known to play important roles in many different processes. However, their roles in shaping the early steps in embryogenesis have remained largely hidden. In this issue of Developmental Cell, Rosa et al. show that the miR-430/427/302 family of microRNAs has a distinct effect on Nodal signaling, affecting mesendoderm ...
Li Chao - - 2009
Mammalian parthenogenetic embryos (pE) are not viable due to placental deficiency, presumably resulting from lack of paternally expressed imprinted genes. Pluripotent parthenogenetic embryonic stem (pES) cells derived from pE could advance regenerative medicine by avoiding immuno-rejection and ethical roadblocks. We attempted to explore the epigenetic status of imprinted genes in ...
Kiessling Ann A - - 2009
To understand the molecular pathways that control early human embryo development. Improved methods of linear amplification of mRNAs and whole human genome microarray analyses were utilized to characterize gene expression in normal appearing 8-Cell human embryos, in comparison with published microarrays of human fibroblasts and pluripotent stem cells. Many genes ...
M??o Simone Cristina - - 2009
Ooplasmic factors drive nuclear organization after fertilization and are also important for re-programming in nuclear transfer procedures, in which artificial activation is essential for reconstructed embryos to progress in development. The present research evaluated the effect of pronuclear transfer (PT) between zygotes parthenogenetically activated with ionomycin followed by strontium (S) ...
Fan Yong - - 2009
The generation of patient-specific nuclear transfer embryonic stem cells holds huge promise in modern regenerative medicine and cell-based drug discovery. Since human in vivo matured oocytes are not readily available, human therapeutic cloning is developing slowly. Here, we investigated for the first time whether human polyspermic zygotes could support preimplantation ...
Nagy Nándor - - 2009
Bursa of Fabricius is a primary lymphoid organ in the birds and its microenvironment is responsible for the B cell maturation. The epithelial anlage develops through epithelial-mesenchymal interaction into which -as a third party - hemopoietic cells immigrate. Chemical bursectomy can be made by dipping or injecting eggs by testosterone ...
Furuya Hidetaka - - 2009
A new species of dicyemid mesozoan is described from Opisthoteuthis depressa Iijima and Ikeda, 1895, collected from Suruga Bay in Japan. Dicyemennea umbraculum n. sp. is a medium species that reaches about 3,500 mum in length. This species attaches to the surface of the renal appendages. The vermiform stages are ...
Wang Kai - - 2009
Interspecies somatic cell nuclear transfer (iSCNT) has the potential to become a useful tool to address basic questions about the nucleus-cytoplasm interactions between species. It has also been proposed as an alternative for the preservation of endangered species and to derive autologous embryonic stem cells. Using chimpanzee/ bovine iSCNT as ...
Nishioka Noriyuki - - 2009
Outside cells of the preimplantation mouse embryo form the trophectoderm (TE), a process requiring the transcription factor Tead4. Here, we show that transcriptionally active Tead4 can induce Cdx2 and other trophoblast genes in parallel in embryonic stem cells. In embryos, the Tead4 coactivator protein Yap localizes to nuclei of outside ...
Li Jianyuan - - 2009
Somatic cell nuclear transfer (SCNT) was used to generate patient-specific embryonic stem cells (ESCs) from blastocysts cloned by nuclear transfer (ntESCs). In this study, a total of 135 oocytes were obtained from 12 healthy donors (30-35 years). Human oocytes, obtained within 2 h following transvaginal aspiration, were enucleated using a ...
Larina Irina V IV Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, - - 2009
The development of the cardiovascular system is a highly dynamic process dependent on multiple signaling pathways regulating proliferation, differentiation, migration, cell-cell and cell-matrix interactions. To characterize cell and tissue dynamics during the formation of the cardiovascular system in mice, we generated a novel transgenic mouse line, Tg(Flk1::myr-mCherry), in which endothelial ...
Siqueira da Fonseca S A - - 2009
OBJECTIVES: In this study, we aimed at determining whether human immature dental pulp stem cells (hIDPSC) would be able to contribute to different cell types in mouse blastocysts without damaging them. Also, we analysed whether these blastocysts would progress further into embryogenesis when implanted to the uterus of foster mice, ...
Lei Lei - - 2009
Polyploid mouse embryos are important models for understanding the mechanisms of cleavage and preimplantation development in mammals. In this study, hexaploid (6n) mouse embryos were produced by the electrofusion of blastomeres from diploid (2n) and tetraploid (4n) embryos at the 2-cell stage. Furthermore, the developmental pattern of hexaploid embryos was ...
Liu Hong-Bo - - 2009
Miniature pigs are valuable for research in xenotransplantation and as models for investigating human diseases. Although many mammalian species have been cloned, the success rates have been very low, especially in the pig. In the present study, an attempt was made to optimize somatic cell nuclear transfer (SCNT) protocols for ...
Fu J-J - - 2009
Embryo implantation involves invasion of placental extravillous trophoblast cell (EVTs) into the uterus. Hyperactive EVT invasion occurs in hydatidiform moles and choriocarcinomas. We have previously demonstrated that the 20S proteasome is involved in mouse embryo implantation and its action is mediated via regulating the expression and activities of matrix metalloproteinase ...
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