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  • diploid
  • Unlike most other eukaryotes, ciliates have two different sorts of nuclei: a tiny, diploid micronucleus (the "generative nucleus," which carries the germline of the cell), and a large, polyploid macronucleus (the "vegetative nucleus," which takes care of general cell regulation, expressing the phenotype of the organism). (wikipedia.org)
  • In meiosis is a diploid cell (2N) duplicates its DNA once and undergoes two rounds of cell division to produce four haploid (1N), germ cells that promotes the recombination of large expanses of chromosomal DNA, potentially similar in size to those lost or gained in cancer. (wikipedia.org)
  • Whitehead Institut
  • Analyzing the complete gene-expression profiles of both cloned and fertilization-derived stem cells in mice, scientists at Whitehead Institute for Biomedical Research now have concluded that the two are, in fact, indistinguishable. (eurekalert.org)
  • fibroblasts
  • Virally induced expression of four transcription factors Oct4, Sox2, c-Myc, and Kfl4 (Yamanaka factors) is sufficient to create pluripotent (iPS) cells from adult fibroblasts. (wikipedia.org)
  • germ cells
  • What's more, these reprogrammed skin cells can give rise to live mice, contributing to every kind of tissue type, and can even be transmitted via germ cells (sperm or eggs) to succeeding generations. (mit.edu)
  • Eukaryotic
  • The defining feature that sets eukaryotic cells apart from prokaryotic cells (Bacteria and Archaea) is that they have membrane-bound organelles, especially the nucleus, which contains the genetic material enclosed by the nuclear membrane. (wikipedia.org)
  • Eukaryotic cells also contain other membrane-bound organelles such as mitochondria and the Golgi apparatus. (wikipedia.org)
  • In 1967, Lynn Margulis provided microbiological evidence for endosymbiosis as the origin of chloroplasts and mitochondria in eukaryotic cells in her paper, On the origin of mitosing cells. (wikipedia.org)
  • Eukaryotic cells are typically much larger than those of prokaryotes having a volume of around 10,000 times greater than the prokaryotic cell. (wikipedia.org)
  • Chemokinesis is chemically prompted kinesis, a motile response of unicellular prokaryotic or eukaryotic organisms to chemicals that cause the cell to make some kind of change in their migratory/swimming behaviour. (wikipedia.org)
  • Photosynthetic eukaryotes originated following a primary endosymbiotic event, where a heterotrophic eukaryotic cell engulfed a photosynthetic cyanobacterium-like prokaryote that became stably integrated and eventually evolved into a membrane-bound organelle: the plastid. (wikipedia.org)
  • The ciliates are a group of protozoans characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different undulating pattern than flagella. (wikipedia.org)
  • genes
  • Although their genes may be identical, bacteria or cancer cells, for example, may react differently to a given drug. (wallenberg.org)
  • Most of them die, but a small proportion may react a little differently and survive - even though their genes are identical. (wallenberg.org)
  • For many years now, researchers have been studying how genes control cell characteristics. (wallenberg.org)
  • Cells control their behavior via gene expression, i.e. the process whereby the genes' DNA sequence is transcribed to the messenger molecule, RNA, which is then decoded to form proteins. (wallenberg.org)
  • For a viable fetus to develop, the egg needs to reprogram the genome of the skin cell, shutting off genes specific for skin tissue and turning on genes needed for embryonic development, genes that are normally dormant in tissue-specific cells. (eurekalert.org)
  • With a series of microarray chips, Brambrink measured which genes were active and which were silent in both kinds of cells. (eurekalert.org)
  • Scientists have made a significant discovery that explains how and why the billions of different cells in our bodies look and act so differently despite containing identical genes. (eurekalert.org)
  • The new work helps towards understanding why a blood cell and a brain cell look and act very differently yet contain exactly the same genes. (eurekalert.org)
  • The study of epigenetics has provided key molecular insights into how every type of cell has its own unique pattern of genes that are either switched on or off in a tightly controlled manner. (eurekalert.org)
  • Then, studies showed that adult neurons uniquely lack a protein that permanently turns off neuronal genes in the rest of the body's cells. (bio-medicine.org)
  • This new study, published in the May 20, 2005, issue of the journal Cell, may be among the first to track a set of genes from stem cell to differentiated neuron. (bio-medicine.org)
  • In contrast to the tight packaging of neural genes in other cells, REST keeps the chromatin in embryonic stem and precursor neurons open and poised for gene activity. (bio-medicine.org)
  • The cell then triggers the expression of an ensemble of genes that coordinates nervous system development by removing REST in three distinct phases, ending with shutting down the REST gene. (bio-medicine.org)
  • Reprogramming, the process of turning on genes that are active in a stem cell and turning off genes that are responsible for cell specialization was pioneered by Shinya Yamanaka, who showed that the introduction of four specific proteins essential during early embryonic development could be used to convert adult cells intopluripotent cells. (stemcellclinic.net)
  • Using artificial viruses called vectors, the team activated the same four genes in a batch of mouse skin cells. (mit.edu)
  • eukaryotes
  • Unlike unicellular archaea and bacteria, eukaryotes may also be multicellular and include organisms consisting of many kinds of tissue and cell types. (wikipedia.org)
  • In his 1938 work Titres et Travaux Scientifiques, Chatton had proposed the two terms, calling the bacteria prokaryotes and organisms with nuclei in their cells eukaryotes. (wikipedia.org)
  • The evolution of photosynthesis, around 3.5 Ga, eventually led to a buildup of its waste product, oxygen, in the atmosphere, leading to the great oxygenation event, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles) dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. (wikipedia.org)
  • Sexual reproduction, which involves the fusion of male and female reproductive cells (gametes) to create a zygote in a process called fertilization is, in contrast to asexual reproduction, the primary method of reproduction for the vast majority of macroscopic organisms, including almost all eukaryotes (which includes animals and plants). (wikipedia.org)
  • clones
  • Human self-reactive T cell clones expressing identical T cell receptor beta chains differ in their ability to recognize a cryptic self-epitope. (ox.ac.uk)
  • We have studied five human in vivo activated T cell clones specific for the region 535-551 of human thyroid peroxidase (TPO) established from a Graves' patient. (ox.ac.uk)
  • Three clones (37, 72, and 73) expressed identical TCR beta and alpha chains rearranging V beta 1.1 and V alpha 15.1, and were considered sister clones. (ox.ac.uk)
  • Fine epitope mapping using nested peptides showed that clones using identical TCR beta chains, identical V alpha, but a different J alpha recognized distinct, nonoverlapping epitopes in the TPO 535-551 region. (ox.ac.uk)
  • To confirm that clones 37 (and its sisters) and 43 recognize different epitopes, the T cell clones were stimulated with a TPO-transfected autologous Epstein-Barr virus (EBV) cell line (TPO-EBV) that presents TPO epitopes afer endogenous processing. (ox.ac.uk)
  • We have shown that thyroid epithelial cells (TEC), the only cells that produce TPO, express HLA class II molecules in Graves' disease and can act as an antigen-presenting cells, presenting TPO after endogenous processing to autoantigen-reactive T cell clones. (ox.ac.uk)
  • Type Ap spermatogonia repeatedly divide mitotically to produce identical cell clones linked by cytoplasmic bridges. (wikipedia.org)
  • Another important area where one can talk of "clones" of cells is neoplasms. (wikipedia.org)
  • However, this view of cancer onset has been challenged in recent years and many tumors have been argued to have polyclonal origin, i.e. derived from two or more cells or clones, including malignant mesothelioma. (wikipedia.org)
  • All the granulosa cells in a Graafian follicle are in fact clones. (wikipedia.org)
  • Whereas, the cells of clones dealt with here are specialized cells of a multicellular organism (usually vertebrates), and reside at quite distant places. (wikipedia.org)
  • Antigen
  • They will return to NIH daily the first week (from Monday through Thursday) to monitor for CD4 cell counts, plasma viral burden, p24 antigen levels, HIV levels and the presence of the NeoR gene, and then weekly for the next 5 weeks for these tests and others to monitor blood and urine chemistry, blood counts and immune function markers. (clinicaltrials.gov)
  • undergo
  • Non-infected twins will undergo a procedure called apheresis to collect white blood cells. (clinicaltrials.gov)
  • In addition to the above procedures, patients with a baseline CD4 lymphocyte count less than 100 cells per cubic millimeter of blood will be asked to undergo apheresis periodically to obtain the most accurate results for determining how long the NeoR gene persists in the blood. (clinicaltrials.gov)
  • Pluripotent stem cells undergo further specialization into multipotent progenitor cells that then give rise to functional cells. (wikipedia.org)
  • organism
  • It was then that we realized that even in an organism as simple as yeast, the DNA decoding process gives rise to a wide diversity of RNA, which may change the way the cell may react. (wallenberg.org)
  • Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. (wikipedia.org)
  • citation needed] Development begins when a sperm fertilizes an egg and creates a single cell that has the potential to form an entire organism. (wikipedia.org)
  • Although the cells of the inner cell mass can form virtually every type of cell found in the human body, they cannot form an organism. (wikipedia.org)
  • A eukaryote (/juːˈkæri.oʊt/ or /juːˈkæriət/) is any organism whose cells have a cell nucleus and other organelles enclosed within membranes. (wikipedia.org)
  • differences
  • We show that apparent voltage threshold differences for seeing effects of the 5- and 3-phosphatase activities in cells are not due to different intrinsic voltage dependence of these reactions. (nih.gov)
  • Russian researchers have concluded that reprogramming does not create differences between reprogrammed and embryonic stem cells. (stemcellclinic.net)
  • Recent studies highlighted significant differences between these two types of stem cells, although only a limited number of cell lines of different origins were analyzed. (stemcellclinic.net)
  • Differences between cells that did occur were thought to be the result of random factors. (stemcellclinic.net)
  • sperm
  • Germ line cells are any line of cells that give rise to gametes-eggs and sperm-and thus are continuous through the generations. (wikipedia.org)
  • Spermatocytogenesis is the male form of gametocytogenesis and involves stem cells dividing to replace themselves and to produce a population of cells destined to become mature sperm. (wikipedia.org)
  • These cells do not directly participate in producing sperm, instead serving to maintain the supply of stem cells for spermatogenesis. (wikipedia.org)
  • genome
  • Thus, different cells can have very different physical characteristics despite having the same genome. (wikipedia.org)
  • Each of the approximately 100 trillion (1014) cells in an adult human has its own copy or copies of the genome except certain cell types, such as red blood cells, that lack nuclei in their fully differentiated state. (wikipedia.org)
  • Article 11 of UNESCO's Universal Declaration on the Human Genome and Human Rights asserts that the reproductive cloning of human beings is contrary to human dignity, that a potential life represented by the embryo is destroyed when embryonic cells are used, and there is a significant likelihood that cloned individuals would be biologically damaged, due to the inherent unreliability of cloning technology. (wikipedia.org)
  • donor
  • To create a clone, a scientist removes the nucleus from a donor cell, then places it into an egg from which the nucleus has been removed. (eurekalert.org)
  • If the NeoR gene cannot be detected after the first cell infusion, the entire procedure (donor apheresis, gene marking and infusion of cells) will be repeated twice-about once every 6 weeks. (clinicaltrials.gov)
  • tissues
  • Embryonic stem cells with identical genomes grow into distinctive tissues, such as heart, bone, and brain. (bio-medicine.org)
  • They serve as a sort of internal repair system in many tissues, dividing essentially without limit to replenish other cells. (stemcellclinic.net)
  • The cells of the inner cell mass go on to form virtually all of the tissues of the human body. (wikipedia.org)
  • Such cells, tissues, and organs would neither trigger an immune response nor require the use of immunosuppressive drugs. (wikipedia.org)
  • In Aubrey de Grey's proposed SENS (Strategies for Engineered Negligible Senescence), one of the considered options to repair the cell depletion related to cellular senescence is to grow replacement tissues from stem cells harvested from a cloned embryo. (wikipedia.org)
  • occurs
  • when cell division occurs, the sister chromatids are sheared and mis-segregated which results in an aneuploid state. (wikipedia.org)
  • blastocyst
  • The egg develops into a blastocyst, an early stage embryo consisting of no more than 100 or so cells. (eurekalert.org)
  • The scientist can then either remove the stem cells from this blastocyst, or place it into a uterus where it has the potential to develop into a fetus. (eurekalert.org)
  • But this entire process is almost never perfect, and nearly all cells in a cloned blastocyst retain some memory of their original source. (eurekalert.org)
  • Studies have demonstrated that a small number of stem cells in the blastocyst appear to be spared this faulty reprogramming. (eurekalert.org)
  • When stem cells from a cloned blastocyst are removed and placed into a dish, most die. (eurekalert.org)
  • The blastocyst has an outer layer of cells, and inside this hollow sphere, there is a cluster of cells called the inner cell mass. (wikipedia.org)
  • nuclei
  • Three functionally separate spermatogonial cell types are recognised on the basis of the appearance of the nuclei: type A dark spermatogonia (Ad), type A pale spermatogonia (Ap), and type B spermatogonia (B). The population of spermatogonia is maintained by type Ad spermatogonia. (wikipedia.org)
  • whereas
  • T cell clone 37 recognizes the TEC, whereas it is stimulated poorly by the TPO loaded to autologous peripheral blood mononuclear cells (PBMC). (ox.ac.uk)
  • Image J) checker-board analysis, which provides data about migration of identical cells, whereas, in Protozoa (e.g. (wikipedia.org)
  • genetic
  • But genetic information alone does not explain individual cell behavior. (wallenberg.org)
  • Here, the scientists took genetic material known to be resistant to the toxic drug neomycin, and spliced it into the genomes of each cell right beside Oct4 and Nanog. (mit.edu)
  • The genetic material, in the form of deoxyribonucleic acid (DNA), continues to shorten with each cell division, and cells eventually stop dividing when they sense that their DNA is critically shortened. (wikipedia.org)
  • immune
  • It may also provide insights into other diseases, such as small cell lung cancer, which mistakenly make neuronal proteins, or neurological syndromes, where neuronal proteins produced by cancers may trigger the immune cells to attack the nervous system. (bio-medicine.org)
  • This phase I/II pilot project will evaluate the survival, tolerance, safety, and efficacy of infusions of activated, gene marked, syngeneic T lymphocytes obtained from HIV seronegative identical twins on the functional immune status of HIV infected twin recipients. (clinicaltrials.gov)
  • zygote
  • In mammals, only the zygote and subsequent blastomeres are totipotent, while in plants many differentiated cells can become totipotent with simple laboratory techniques. (wikipedia.org)
  • transplantation
  • Patients with high risk or refractory malignancies, or non-malignant disorders amenable to stem cell transplantation therapy but lacking conventional related or unrelated donors will be eligible for this protocol. (clinicaltrials.gov)
  • The CliniMACS CD34 Reagent System is a medical device that is used in vitro to select and enrich CD34+ cells from heterogeneous hematologic cell populations for transplantation in cases where this is clinically indicated. (clinicaltrials.gov)
  • Jaenisch
  • Tobias Brambrink, a postdoctoral researcher in the Jaenisch lab, tried a different approach, comparing gene expression in cloned and fertilization-derived stem cells. (eurekalert.org)
  • In my opinion, these results solidify the argument that while a cloned animal is abnormal, a cloned stem cell is perfectly normal," says Jaenisch. (eurekalert.org)
  • These reprogrammed cells, by all criteria that we can apply, are indistinguishable from embryonic stem cells," says Whitehead Member and MIT professor of biology Rudolf Jaenisch , senior author of the paper that appeared online June 6 in Nature . (mit.edu)
  • genomic
  • In other words, the egg needs to erase all tissue-specific memories from the skin cell and revert it into a genomic blank slate. (eurekalert.org)
  • Melanoma tumor cells that replicate via meiomitosis may become immortal due to the expression of telomerase, but this comes at the cost of meiotic proteins and genomic instability. (wikipedia.org)
  • Research suggests that genomic instability affects the cancer cells' ability to metastasize. (wikipedia.org)
  • Yamanaka
  • Yamanaka was awarded the 2012 Nobel Prize along with Sir John Gurdon for the discovery that mature stem cells can be reprogrammed to become pluripotent. (stemcellclinic.net)
  • daughter
  • If the DNA content in G2 is 2X, what is the DNA content of each daughter cell at telophase? (coursehero.com)
  • If the DNA content in G1 is 2S, what is the DNA content of each of the daughter cells at telophase? (coursehero.com)
  • Differentiation continues in adulthood as adult stem cells divide and create fully differentiated daughter cells during tissue repair and during normal cell turnover. (wikipedia.org)
  • Patients
  • Patients who do not have a single UCB unit that will deliver the minimum required cell dose, two partially HLA-matched UCB units which together meet the minimum cell dose requirement, can be used for 1 transplant. (clinicaltrials.gov)
  • Oct4
  • The trick would be to figure out a way to harvest Oct4- and Nanog-active cells from the rest of the population. (mit.edu)
  • cell's
  • The general equation for such a system of rules is kks, where k is the number of possible states for a cell, and s is the number of neighboring cells (including the cell to be calculated itself) used to determine the cell's next state. (wikipedia.org)
  • Others are the alveoli, small vesicles under the cell membrane that are packed against it to form a pellicle maintaining the cell's shape, which varies from flexible and contractile to rigid. (wikipedia.org)
  • repeatedly
  • The term "memory" came from an aerospace nickel-cadmium application in which the cells were repeatedly discharged to 25% of available capacity (plus or minus 1%) by exacting computer control, then recharged to 100% capacity without overcharge. (wikipedia.org)
  • unicellular
  • A somewhat similar concept is that of clonal colony (also called a genet), wherein the cells (usually unicellular) also share a common ancestry, but which also requires the products of clonal expansion to reside at "one place", or in close proximity. (wikipedia.org)
  • The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. (wikipedia.org)
  • adult
  • Scientists concluded that the type of adult cells that were reprogrammed and the process of reprogramming did not leave any marks. (stemcellclinic.net)
  • variation
  • Another source of phenotypic variation will be described - the first passage time for a molecular population to cross a fixed threshold in growing cells. (santafe.edu)
  • division
  • However, during course of cell division, one of the cells can get mutated further and acquire new characteristics to diverge as a new clone. (wikipedia.org)
  • Instead, a 'raft' of microtubules, the phragmoplast, is formed from the mitotic spindle and cell division involves the use of this phragmoplast in the production of a cell plate. (wikipedia.org)
  • biology
  • In developmental biology, cellular differentiation is the process where a cell changes from one cell type to another. (wikipedia.org)
  • functional
  • The B cells in the body have two important phenotypes (functional forms) -- the antibody secreting, terminally differentiated (that is, they cannot divide further) plasma cells, and the memory and the naive cells-both of which retain their proliferative potential. (wikipedia.org)
  • different
  • Using Förster resonance energy transfer probes specific for different PIs in living cells with zebrafish VSP, we quantitate both voltage-dependent 5- and 3-phosphatase subreactions against endogenous substrates. (nih.gov)
  • Stem cells are specialized,undifferentiated cellsthat can divide and have the remarkable potential to develop into many different cell types in the body during early life and growth. (stemcellclinic.net)
  • For instance, two plasma cells belonging to the same clone could be derived from different memory cells (in turn with shared clonality) and could be residing in quite distant locations, such as the cervical (in the neck) and inguinal (in the groin) lymph nodes. (wikipedia.org)
  • cellular
  • A cellular automaton consists of a regular grid of cells, each in one of a finite number of states, such as on and off (in contrast to a coupled map lattice). (wikipedia.org)
  • Typically, the rule for updating the state of cells is the same for each cell and does not change over time, and is applied to the whole grid simultaneously, though exceptions are known, such as the stochastic cellular automaton and asynchronous cellular automaton. (wikipedia.org)
  • Special types of cellular automata are reversible, where only a single configuration leads directly to a subsequent one, and totalistic, in which the future value of individual cells only depends on the total value of a group of neighboring cells. (wikipedia.org)
  • One way to simulate a two-dimensional cellular automaton is with an infinite sheet of graph paper along with a set of rules for the cells to follow. (wikipedia.org)
  • The former, named after the founding cellular automaton theorist, consists of the four orthogonally adjacent cells. (wikipedia.org)
  • bone
  • The purpose of the related stem cells is the give the bone marrow a 'jump start' towards recovery. (clinicaltrials.gov)
  • Ultimately, the cord blood cells will grow and permanently rescue the bone marrow. (clinicaltrials.gov)
  • Paroxysmal nocturnal hemoglobinuria is a disorder of bone marrow cells resulting in shortened life of red blood cells, which is also a result of clonal expansion, i.e., all the altered cells are originally derived from a single cell, which also somewhat compromises the functioning of other "normal" bone marrow cells. (wikipedia.org)