• fetal
  • In January 2018, a team of scientists in Shanghai announced the successful cloning of two female crab-eating macaques (named Zhong Zhong and Hua Hua) from fetal nuclei. (wikipedia.org)
  • Irving, "'New age' embryology text books: 'Pre-embryo', 'pregnancy' and abortion counseling: Implications for fetal research", Linacre Quarterly May 1994, 61(2):42-62. (lifeissues.net)
  • The issue arises in a number of fields including science, religion, philosophy, and law, and is most acute in debates relating to abortion, stem cell research, reproductive rights, and fetal rights. (wikipedia.org)
  • sperm
  • Embryo development begins with a sperm fertilizing an egg to become a zygote which undergoes many cleavages to develop into a ball of cells called a morula. (wikipedia.org)
  • At this point, the question may be raised as to how an embryo is created without a sperm uniting with the egg. (cbhd.org)
  • In the normal process of fertilization and embryo formation, the egg and sperm cells each have only one copy, or half, of the DNA necessary to code for a fully functioning human being. (cbhd.org)
  • At the point of union of the sperm and egg, an embryo is created. (cbhd.org)
  • According to the definitions included in the bill, Clone a human being or cloning a human being, shall mean the creation of a human being by any means other than by the fertilization of a naturally intact oocyte of a human female by a naturally intact sperm of a human male. (natcath.org)
  • As such, in vitro fertilization, a useful method of producing embryos (joining egg and sperm) for implantation into women who have been unable or have had difficulty getting pregnant, would not be prohibited under the bill. (natcath.org)
  • When the sperm fertilizes the egg, the sperm nucleus and centrosomes are deposited within the egg, which causes a cytoplasmic flux resulting in the movement of the sperm pronucleus and centrosomes towards one pole. (wikipedia.org)
  • The centrosomes deposited by the sperm seem to be responsible for the establishment of the posterior pole within the one cell embryo. (wikipedia.org)
  • Xenopus
  • In many animals such as Drosophila and Xenopus, the mid blastula transition (MBT) is a crucial step in development during which the maternal mRNA is degraded and control over development is passed to the embryo. (wikipedia.org)
  • In Xenopus embryos, the blastula is composed of three different regions. (wikipedia.org)
  • vertebrate
  • In the vertebrate embryo, a rhombomere is a transiently divided segment of the developing neural tube, within the hindbrain region (a neuromere) in the area that will eventually become the rhombencephalon. (wikipedia.org)
  • tissues
  • A germ layer is a group of cells in an embryo that interact with each other as the embryo develops and contribute to the formation of all organs and tissues. (asu.edu)
  • Most plants, in particular, can safely reach temperatures of −4 °C to −12 °C. Certain bacteria, notably Pseudomonas syringae, produce specialized proteins that serve as potent ice nucleators, which they use to force ice formation on the surface of various fruits and plants at about −2 °C. The freezing causes injuries in the epithelia and makes the nutrients in the underlying plant tissues available to the bacteria. (wikipedia.org)
  • mice
  • Hurlbut's first choice is the human equivalent of cdx2, the gene in mice that directs the formation of the placenta. (slate.com)
  • Aggregation chimeras are produced by a technique that involves removing the zonae pellucidae from around 8-16 cell embryos of different strains of mice and pushing the morulae together so that the cells can aggregate. (thefreedictionary.com)
  • cells
  • Changes in dendrite-mediated interaction between nerve cells can contribute to the formation of new memories. (pewtrusts.org)
  • In this video article, we describe our technique for targeted laser ablation of kidney nephron cells in the zebrafish embryo kidney, or pronephros. (jove.com)
  • Scheme of the formation of embryo cells of cereals with the base chromosome numbers multiple of "7" at the initial stage of development, with the critical number of 588 cells. (intechopen.com)
  • The arrows in a circle indicate the direction of flows, the shaded rectangles - the location of the cells, and the shape of the envelope lines around the perimeter of the shaded rectangles - the shape of the embryo. (intechopen.com)
  • The first, by Drs. Donald Landry and Howard Zucker of Columbia University, proposes that we take stem cells from embryos at the same point at which we take organs from children and adults: right after they die. (slate.com)
  • He cites an experiment in which stem cells from arrested frog embryos were injected into normal frog embryos. (slate.com)
  • Twenty-five percent of the cells began to divide again and were absorbed into the new embryos. (slate.com)
  • They're also wary of the Columbia team's suggestion that stem cells could be harvested from embryos "in extremis," i.e., near death. (slate.com)
  • In other words, the parts of an embryo-or the parts that normally would become an embryo-might produce stem cells, even if, to avoid the moral problem, we kept these parts incomplete or severed. (slate.com)
  • Then, once the cell begins to divide, reactivate the gene, too late to organize the embryo but early enough to make stem cells. (slate.com)
  • The addition of the two growth phases into the cell cycle allows for the cells to increase in size, as up to this point the blastomeres undergo reductive divisions in which the overall size of the embryo does not increase, but more cells are created. (wikipedia.org)
  • Research is needed to determine the most viable stem cell lines and reliable ways to promote the differentiation of pluripotent stem cells into specific cell types (neurons, muscle cells, etc. (jci.org)
  • The Kit proto-oncogene encodes a tyrosine kinase receptor whose ligand is a paracrine protein called stem cell factor (SCF), which is important in hematopoiesis (formation of cells in blood). (wikipedia.org)
  • this approach has been championed as an answer to the many issues concerning embryonic stem cells (ESC) and the destruction of viable embryos for medical use, though questions remain on how homologous the two cell types truly are. (wikipedia.org)
  • Stem cells can then be obtained by the destruction of this clone embryo for use in therapeutic cloning or in the case of reproductive cloning the clone embryo is implanted into a host mother for further development and brought to term. (wikipedia.org)
  • The aim of carrying out this procedure is to obtain pluripotent cells from a cloned embryo. (wikipedia.org)
  • Embryonic stem cells are undifferentiated cells of an embryo. (wikipedia.org)
  • Although some chimeras do arise naturally, most are produced experimentally, either by mixing cells of very early embryos or by tissue grafting in late embryos or adults. (thefreedictionary.com)
  • Two techniques used to form chimeras by mixing embryo cells are aggregation and injection. (thefreedictionary.com)
  • They develop spontaneously from germ cells in the gonads of certain mouse strains, or from cells in early embryos transplanted to ectopic sites. (thefreedictionary.com)
  • Embryonal carcinoma cells from several sources, including spontaneous and embryo-derived tumors and cultured lines selected to carry specific mutations or even human chromosomes, have contributed to normal chimeras. (thefreedictionary.com)
  • Originating from the lateral ganglionic eminence, one of the three embryonic structures that eventually become specific parts of the brain, the sub-ventricular zone (SVZ) is a group of cells that develop along the surface of the ventricular layer of the brain, following the creation of the cortical plate in embryos. (wikipedia.org)
  • therapeutic
  • Along the way we must reduce the emotional valence of phrases such as "therapeutic cloning" and "destruction of embryos. (jci.org)
  • Given the spin that science and the media have put on the latest achievement in medical science - the cloning of the first human embryo - some reading this article may truly believe that there are good, and even therapeutic, reasons for human cloning and that human cloning cannot really result in the development of a human being to the point of birth. (cbhd.org)
  • cell
  • The good news is that we may have figured out how to solve the moral problem that's been holding up stem-cell research. (slate.com)
  • Landry suggests that this point is "the irreversible arrest of cell division," which conveniently applies to huge numbers of embryos frozen in IVF clinics. (slate.com)
  • He seems to be the only person in this debate who has figured out that the Catholic fixation on the technical definition of a human embryo, which stem-cell researchers regard as a roadblock, actually presents an opportunity. (slate.com)
  • The plan would be to follow the recipe for cloning-put the nucleus of a body cell into a gutted egg cell-but turn off cdx2. (slate.com)
  • Margaret Adaline Reed Lewis (1881-1970) was an American cell biologist and embryologist who made contributions to cancer research and cell culture techniques, and was likely the first person to successfully grow mammalian tissue in vitro. (wikipedia.org)
  • In 1908, Margaret Reed researched in Berlin in Max Hartmann's lab where she performed probably the first in vitro mammalian cell culture with guinea pig bone marrow by explanting the bone marrow and placing it into a nutrient-rich agar produced by fellow lab researcher Rhoda Erdmann and incubating the sample. (wikipedia.org)
  • Since the Lewises main interest was microscopic cell structures, their objective was to create optically clear media, which led to the creation of the Locke-Lewis solution. (wikipedia.org)
  • As a result, this couple's greatest impact on embryology and cell biology in the twentieth century was teaching later generations of biologists the basic factors involved in tissue culture based on what they had learned from their research. (wikipedia.org)
  • With so many avenues opened by cell culture to explore, Margaret Lewis and her husband diverged in their area of study, with Margaret Lewis choosing to focus on microbiological problems, which involved close observations of chick embryo intestines reacting to typhoid bacilli in the medium in which it was grown. (wikipedia.org)
  • During the blastula stage of development, a significant amount of activity occurs within the early embryo to establish cell polarity, cell specification, axis formation, and regulate gene expression. (wikipedia.org)
  • The study of the blastula and of cell specification has many implications on the field of stem cell research as well as the continued improvement of fertility treatments. (wikipedia.org)
  • A stem cell is defined by two properties (see A stem cell research lexicon ). (jci.org)
  • In the first one, first messenger cross through the cell membrane, binding and activating intracellular receptors localized at nucleus or cytosol, which then act as transcriptional factors regulating directly gene expression. (wikipedia.org)
  • That nucleus is then replaced with the nucleus from a donor s skin, liver, brain or any other cell in the body. (natcath.org)
  • The technique consists of taking an enucleated oocyte (egg cell) and implanting a donor nucleus from a somatic (body) cell. (wikipedia.org)
  • It is a technique for cloning in which the nucleus of a somatic cell is transferred to the cytoplasm of an enucleated egg. (wikipedia.org)
  • The nucleus of the donor egg cell is removed and discarded, leaving it 'deprogrammed. (wikipedia.org)
  • After being inserted into the egg, the somatic cell nucleus is reprogrammed by its host egg cell. (wikipedia.org)
  • Somatic cell nuclear transplantation has become a focus of study in stem cell research. (wikipedia.org)
  • adult
  • Instead of whining about the church's insistence on the continuity of personhood from embryo to adult, Hurlbut has seized on the point of discontinuity: the non-personhood of anything before or less than an embryo. (slate.com)
  • Our general approach to MSC-based cartilage repair addresses the differences observed between early rapid stages of cartilage formation and the gradual remodeling (maturation) that results in a tissue capable of adult function. (upenn.edu)
  • Developmental Biology
  • Flat Mount Preparation for Observation and Analysis of Zebrafish Embryo Specimens Stained by Whole Mount In situ Hybridization Christina N. Cheng 1 , Yue Li 1 , Amanda N. Marra 1 , Valerie Verdun 1 , Rebecca A. Wingert 1 1 Department of Biological Sciences, University of Notre Dame The zebrafish embryo is an excellent model for developmental biology research. (jove.com)
  • chicks
  • She researched how body and head segments formed in chicks (Gallus gallus) and spiny dogfish (Squalus acanthias). (asu.edu)
  • Scheme
  • Hurlbut, an earnest young member of the council's conservative wing, has been working for two years on a scheme to end-run the problem of killing embryos. (slate.com)
  • development
  • Read more about his research into this phenomenon, also known as "handedness," which plays an important role in embryonic development as well as in genetic diseases and birth defects. (pewtrusts.org)
  • Recording and contextualizing the science of embryos, development, and reproduction. (asu.edu)
  • These Aims were designed to allow the testing of our hypotheses that control over the MSC microenvironment, and inclusion of signals present during normal development that are both permissive and instructive for cartilage formation and maturation, will lead to the generation of constructs with properties akin to native tissue and improved repair. (upenn.edu)
  • The history of Earth concerns the development of planet Earth from its formation to the present day. (wikipedia.org)
  • form
  • Freezing does not start until the temperature is low enough to provide enough energy to form stable nuclei. (wikipedia.org)
  • proteins
  • Further, ZO proteins interact with dual residency proteins localizing to the plasma membrane and the nucleus. (hindawi.com)
  • human
  • Should blastocysts be protected under the same laws that govern research on human subjects? (jci.org)
  • If successful, his campaign would essentially shut down any human genetic bioscience research efforts in Missouri. (natcath.org)
  • If his view prevails, one of the most ambitious research efforts in the Midwest may be forced to move elsewhere, and university work on human genetics could be in jeopardy. (natcath.org)
  • create
  • How could we create functioning parts of an embryo without the whole? (slate.com)
  • If a hypothetical nucleus is too small, the energy that would be released by forming its volume is not enough to create its surface, and nucleation does not proceed. (wikipedia.org)
  • scientists
  • The above quote from Ian Wilmut, the man who captured the world's attention with his creation of Dolly, the cloned sheep, should awaken us all to the vast power of the scientific community, as well as to the desire for total control held by so many scientists in this post-modern era. (cbhd.org)
  • Instead of calling this cloned organism an embryo, which is precisely what it is, scientists have labeled it an "activated egg. (cbhd.org)
  • thus
  • For example, the tissue factor pathway in the coagulation cascade of secondary hemostasis is the primary pathway leading to fibrin formation, and thus, the initiation of blood coagulation. (wikipedia.org)
  • work
  • Mendel's work went largely unnoticed after its first publication in 1866, but was rediscovered in the late 19th century by Hugo de Vries, Carl Correns, and Erich von Tschermak, who (claimed to have) reached similar conclusions in their own research. (wikipedia.org)
  • shown
  • Our progress during the ongoing grant has shown a role for matrix and cellular density, the timing of material degradation, introduction of soluble inductive factors, and mechanical loading (both compression and sliding contact) in guiding cartilage formation and maturation. (upenn.edu)
  • Vestibular nuclei have been shown to span all the rhombomeres, some correlating with the boundaries of the rhombomeres. (wikipedia.org)
  • whole
  • The distinction Hurlbut wants to draw and exploit is between a whole embryo and its parts. (slate.com)
  • Enter
  • To receive news and publication updates for BioMed Research International, enter your email address in the box below. (hindawi.com)