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Chen S H - - 2008
Egg cells of Torenia fournieri were isolated from embryo sacs 1 day after anthesis using enzymatic digestion or mechanical dissection. About 5% of the egg cells and zygotes (2-3 from 50 ovules) could be mechanically dissected within 2 h. When 0.1% cellulase and 0.1% pectinase were added to the mannitol ...
Warger William C WC - - 2008
Since 1978 in vitro fertilization (IVF) procedures have resulted in the birth of over 3 million babies. Yet in 2005, IVF procedures had a live birth rate of only 34%, with 32% of these births resulting in multiple pregnancies. These multiple pregnancies were directly attributed to the transfer of multiple ...
Ambartsumyan Gayane - - 2008
Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and are a major cause of spontaneous miscarriage or birth defects. Nonetheless, model systems suitable for the study ...
Chugh Archana - - 2008
The uptake of five fluorescein labeled cell-penetrating peptides (Tat, Tat(2), mutated-Tat, peptide vascular endothelial-cadherin and transportan) was studied in wheat immature embryos. Interestingly, permeabilization treatment of the embryos with toluene/ethanol (1 : 20, v/v with permeabilization buffer) resulted in a remarkably higher uptake of cell-penetrating peptides, whereas nonpermeabilized embryos failed ...
Mortensen Richard - - 2008
Under some circumstances, it may be desirable to produce a mouse cell clone in which both alleles of a desired gene are mutated. This may be because the mutation causes embryonic lethality in homozygous animals, or to test cultured cells before an animal is produced. This protocol details an easy ...
Liang Min - - 2008
In this study, we show genetic modifier genes of Tp53 that can exacerbate embryonic abnormalities. Using a mouse model in which CE/J mice were crossed with the Tp53-null 129/Sv (129-Trp53(tm1 Tyj)) mice, a subset of Tp53+/- and -/- male and female embryos died during gestation. Our hypothesis, based on the ...
Yamazaki, Atsuko
The canonical Wnt pathway plays a central role in specifying vegetal cell fate in sea urchin embryos. SpKrl has been cloned as a direct target of nuclear β-catenin. Using Hemicentrotus pulcherrimus embryos, here we show that HpKrl controls the specification of secondary mesenchyme cells (SMCs) through both cell-autonomous and non-autonomous ...
Peng Wen-Ping - - 2008
An instrument to directly measure the charge carried by a cell or a microparticle as well as mass-to-charge ratio of the cell/microparticle was developed for rapid mass distribution measurement. A successful mass spectrum with a record high mass has been demonstrated. In this article, the details of the construction and ...
Nel-Themaat Liesl - - 2008
The production of cloned offspring by nuclear transfer (NT) of semen-derived somatic cells holds considerable potential for the incorporation of novel genes into endangered species populations. Because oocytes from endangered species are scarce, domestic species oocytes are often used as cytoplasts for interspecies NT. In the present study, epithelial cells ...
Vázquez-Manrique Rafael P RP Department of Zoology, University of Cambridge, Cambridge, United - - 2008
Migration of cells within epithelial sheets is an important feature of embryogenesis and other biological processes. Previous work has demonstrated a role for inositol 1,4,5-trisphosphate (IP(3))-mediated calcium signalling in the rearrangement of epidermal cells (also known as hypodermal cells) during embryonic morphogenesis in Caenorhabditis elegans. However the mechanism by which ...
Budirahardja Yemima - - 2008
Acquisition of lineage-specific cell cycle duration is an important feature of metazoan development. In Caenorhabditis elegans, differences in cell cycle duration are already apparent in two-cell stage embryos, when the larger anterior blastomere AB divides before the smaller posterior blastomere P1. This time difference is under the control of anterior-posterior ...
Pézeron Guillaume - - 2008
During gastrulation, dramatic movements rearrange cells into three germ layers expanded over the entire embryo [1-3]. In fish, both endoderm and mesoderm are specified as a belt at the embryo margin. Mesodermal layer expansion is achieved through the combination of two directed migrations. The outer ring of precursors moves toward ...
Gall Laurence - - 2008
It is clear from a wide range of studies that the nuclear/cytoplasmic distribution of Cdc25C has important functional consequences for cell cycle control. It is now admitted that in somatic cells, the localization of Cdc25C in the cytoplasm is required to maintain the cell in an interphasic state and that ...
Torres-Padilla Maria Elena - - 2008
The early preimplantation mouse embryo is a unique system where it is possible to explore the foundations of totipotency and differentiation. Following fertilization, a single cell, the zygote, will give rise to all tissues of the organism. The first signs of differentiation in the embryo are evident at the blastocyst ...
Furuya Hidetaka - - 2008
A new species of dicyemid mesozoan is described from Sepiella japonica Sasaki, 1929, collected from the eastern area of Inland Sea, Osaka Bay, and Kii Strait in Japan. Dicyema sepiellae n. sp. is a large species that reaches about 4,000 microm in length. This species lives in folds of the ...
Fujii Setsuko - - 2008
The appendicularian, Oikopleura dioica is a chordate. Its life cycle is extremely short--approximately 5 days--and its tadpole shape with a beating tail is retained throughout entire life. The tadpole hatches after 3 h of development at 20 degrees C. Here, we describe the cleavage pattern and morphogenetic cell movements during ...
Lerou Paul H - - 2008
During in vitro fertilization, embryos deemed clinically useless based on poor morphology are typically discarded. Here we demonstrate a statistical correlation between the developmental stage of such poor-quality embryos and the yield of human embryonic stem (hES) cell lines. Early-arrested or highly fragmented embryos only rarely yield cell lines, whereas ...
Yamagata Kazuo - - 2008
During mammalian fertilization and pre-implantation development, the highly differentiated gametes revert to undifferentiated cell types following syngamy and then gradually differentiate into individual cell lineages. These processes involve changes in male and female gamete chromatin structure, in global epigenetic modifications and in nuclear architecture. We have developed a live cell ...
Cardona Costa, J.
The blastema is a regenerative tissue with remarkable pluripotency. The aim of this work done on zebrafish (Danio rerio) was to define technical procedures required for obtaining and integrating blastema cells into embryos at the mid blastula transition stage (MBT) and the effect on survival, as well as the capacity ...
Messerschmidt, Daniel Martin
In contrast to other vertebrates, mammalian embryos require a phase of pre-implantation development leading to the formation of extra-embryonic structures that will allow the interaction with the maternal environment. In this period, first the segregation of trophectoderm (TE) and inner cell mass (ICM) takes place. Subsequently, the ICM forms the ...
Raya A - - 2008
Human embryonic stem (hES) cells represent a potential source for cell replacement therapy of many degenerative diseases. Most frequently, hES cell lines are derived from surplus embryos from assisted reproduction cycles, independent of their quality or morphology. Here, we show that hES cell lines can be obtained from poor-quality blastocysts ...
Kawahara Manabu - - 2008
A reliable nuclear transfer method was first reported in 1983; it provided definite evidence that parthenogenetic embryos are lethal at early postimplantation in mammals. Subsequently, nuclear transfer has been extensively used as an important and versatile tool for investigating embryo and somatic-cell cloning and nucleo-cytoplasmic interactions. Further development of this ...
Dietrich Jens Erik - - 2008
Mammalian preimplantation development serves to form a blastocyst, a structure that is able to implant into the mother's uterus to support further development of the embryo proper. In the developing conceptus, the first differentiation events separate the epithelial trophectoderm from the inner cell mass, which is comprised of the primitive ...
Kim Insoon - - 2008
Plasmodesmata provide routes for communication and nutrient transfer between plant cells by interconnecting the cytoplasm of adjacent cells. A simple fluorescent tracer-loading assay was developed to monitor patterns of cell to cell transport via plasmodesmata specifically during embryogenesis. A developmental transition in plasmodesmatal size exclusion limit was found to occur ...
Cheong H T - - 2008
The aim of the present study was to examine the development of pig embryos produced by somatic cell nuclear transfer (NT) using the clonal lines of fetal fibroblasts with different population doublings (PD) per day and sizes. Clonal lines were established by plating fetal fibroblasts from a Day 35 pig ...
Shibata S - - 2008
Nuclear transfer ES (ntES) cells are established from cloned blastocysts generated by somatic cell nuclear transfer and are expected to be an important resource for regenerative medicine. However, cloned mammals, generated by similar methods, show various abnormalities, which suggest disordered gene regulation. Random X chromosome inactivation (XCI) has been observed ...
Kubiak Jacek Z - - 2008
Here, we outline the mechanisms involved in the regulation of cell divisions during oocyte maturation and early cleavages of the mouse embryo. Our interest is focused on the regulation of meiotic M-phases and the first embryonic mitoses that are differently tuned and are characterized by specifically modified mechanisms, some of ...
Lerou Paul H - - 2008
Human embryonic stem (hES) cells are self-renewing, pluripotent cells that are valuable research tools and hold promise for use in regenerative medicine. Most hES cell lines are derived from cryopreserved human embryos that were created during in vitro fertilization (IVF) and are in excess of clinical need. Embryos that are ...
Gendreau Emmanuel - - 2008
Various studies indicate that cell division is a post-germination phenomenon, with radicle protrusion occurring by cell elongation, while others demonstrate that induction of the cell cycle occurs in osmo-conditioned seeds prior to radicle growth. The aim of the present work was to investigate the occurrence of the cell cycle during ...
Gerhart Jacquelyn - - 2008
The early chick embryo contains subpopulations of cells that express lineage-specific transcription factors. We have developed protocols to examine the role of these cells during development that involve labeling them for cell tracking purposes and ablating them within the epiblast. The procedures take advantage of the fact that subpopulations of ...
Lai Shih-Lei - - 2008
Intensive cellular movements occur during gastrulation. These cellular movements rely heavily on dynamic actin assembly. Rho with its associated proteins, including the Rho-activated formin, Diaphanous, are key regulators of actin assembly in cellular protrusion and migration. However, the function of Diaphanous in gastrulation cell movements remains unclear. To study the ...
Kawamura Kazuhiro - - 2008
Optimal maturation of oocytes and successful development of preimplantation embryos is essential for reproduction. We performed DNA microarray analyses of ovarian transcripts and identified glial cell line-derived neurotrophic factor (GDNF) secreted by cumulus, granulosa, and theca cells as an ovarian factor stimulated by the preovulatory LH/hCG surge. Treatment of cumulus-oocyte ...
Goossens Veerle - - 2008
BACKGROUND: Preimplantation genetic diagnosis or screening (PGD, PGS) involves embryo biopsy on Day 3. Opting for one- or two-cell biopsy is a balance between the lowest risk for misdiagnosis on the one hand and the highest chance for a pregnancy on the other hand. METHODS: A prospective controlled trial was ...
Brink Thore C - - 2008
Human inner cell mass (ICM) cells isolated from in vitro fertilized blastocysts are the progenitor cells used to establish in vitro stable human embryonic stem cells (hESCs) which are pluripotent and self-renew indefinitely. This long-term perpetuation of hESCs in the undifferentiated state is thought to be an in vitro adaptation ...
Fujimura Tatsuya - - 2008
Obtaining sufficient transgenic cells via selective cultivation of genetically manipulated somatic cells is difficult due to the limited number of cell divisions. Additionally, if irreversible mutations in a cell's chromosomes occur during selective cultivation and the cell is used as the nuclear donor, somatic cell nuclear transfer (SCNT) embryos often ...
Fulka Helena - - 2008
Gametes of both sexes (sperm and oocyte) are highly specialized and differentiated but within a very short time period post-fertilization the embryonic genome, produced by the combination of the two highly specialized parental genomes, is completely converted into a totipotent state. As a result, the one-cell-stage embryo can give rise ...
Tsujioka T - - 2008
A limited number of reports is available on cryopreservation of in vitro fertilization (IVF)-derived cat blastocysts. In the present study, IVF-derived domestic cat embryos which reached the blastocyst stage either on day 6 or day 7 were cryopreserved by vitrification using Cryotop as a cryodevice. Fresh control and post-warm surviving ...
Ohsugi Mami - - 2008
Initial cell lineages that presage the inner cell mass and extra-embryonic trophectoderm are established when eight blastomeres compact to form polarized morulae in preimplantation mouse development. FILIA has been identified as a binding partner to MATER (maternal antigen that embryos require; also known as NLRP5), which is encoded by a ...
Togashi, Shin
Thesis--University of Tsukuba, D.Sc.(A), no. 218, 1984. 3. 24
Wu Shu-Yu - - 2007
Epithelial-mesenchyme transitions (EMTs) are familiar to all scholars of development. Each animal system utilizes an EMT to produce mesenchyme cells. In vertebrates, for example, there are a number of EMTs that shape the embryo. Early, entry of epiblast cells into the primitive streak is followed by the emergence of mesoderm ...
Brad Amber M - - 2007
The capacity of the preimplantation embryo to undergo apoptosis in response to external stimuli is developmentally regulated. Acquisition of apoptosis does not occur in the cow embryo until between the 8- and 16-cell stages. The purpose of the present experiments was to determine the mechanism by which apoptosis is blocked ...
Kiyomoto Masato - - 2007
In the sea urchin embryo, primary mesenchyme cells (PMCs) are committed early in development to direct skeletogenesis, provided that a permissive signal is conveyed from adjacent ectoderm cells. We showed that inhibition of extracellular matrix (ECM)-ectoderm cells interaction, by monoclonal antibodies (mAb) to Pl-nectin, causes an impairment of skeletogenesis and ...
Lee Eunsong - - 2007
The objective of the present study was to examine the feasibility of the production of autologous porcine somatic cell nuclear transfer (SCNT) blastocysts using oocytes and donor cells from slaughtered ovaries. Therefore, we attempted to optimize autologous SCNT by examining the effects of electrical fusion conditions and donor cell type ...
Nodine Michael D - - 2008
Inter-regional signaling coordinates pattern formation in Arabidopsis thaliana embryos. However, little is known regarding the cells and molecules involved in inter-regional communication. We have characterized two related leucine-rich repeat receptor-like kinases (LRR-RLKs), RECEPTOR-LIKE PROTEIN KINASE1 (RPK1) and TOADSTOOL2 (TOAD2), which are required together for patterning the apical embryonic domain cell ...
Graumann Johannes - - 2008
Embryonic stem (ES) cells are pluripotent cells isolated from mammalian preimplantation embryos. They are capable of differentiating into all cell types and therefore hold great promise in regenerative medicine. Here we show that murine ES cells can be fully SILAC (stable isotope labeling by amino acids in cell culture)-labeled when ...
Tse Pui-Keung - - 2008
Human oviductal epithelial (OE) cells produce complement protein 3 (C3) and its derivatives, C3b and inactivated complement-3b (iC3b). Among them, iC3b is the most potent embryotrophic molecule. We studied the production of iC3b in the oviductal cell/embryo culture system. In the immune system, C3 convertase converts C3 into C3b, and ...
Gerbe François - - 2008
Mesenchyme to epithelium transitions are crucial to embryonic development. The early mouse embryo offers an excellent model to study epithelium formation as during the first three days of development two epithelia are formed, the trophectoderm (TE) and the primitive endoderm (PrE). We have previously shown that PrE cells are determined ...
Chiang S-K - - 2008
In Expt 1, goat antisera against rabbit blastocysts were induced using spleen cell injection and skin-graft for immunosurgical isolation of ICM cells. Goats received rabbit spleen cell suspension (4 x 10(8) cells/ml) intravenously once a week for three consecutive weeks, plus an additional dose (boost injection) 10 days after the ...
Zhurov V - - 2007
Polyembryonic development, where multiple embryos are formed from a single zygote, evolved at least 15 times in six different phyla in animals. The mechanisms leading to polyembryony and the forces that shaped the evolution of the polyembryonic developmental program have remained poorly understood. Recent studies of the polyembryonic development in ...
Lee Sang-Goo - - 2007
In pigs, the morphology and cell number of in vitro-produced blastocysts are inferior to those of their in vivo counterparts. The objective of this study was to increase developmental competence and to gain an understanding of cell allocation in blastocysts derived from the aggregation of four-cell stage porcine embryos produced ...
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