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Somatic-cell Nuclear Transfer
In genetics and developmental biology, somatic cell nuclear transfer (SCNT) is a laboratory strategy for creating a viable embryo from a Somatic cell, body cell and an egg cell. The technique consists of taking a denucleated oocyte (egg cell) and implanting a donor Cell nucleus, nucleus from a somatic (body) cell. It is used in both therapeutic and reproductive cloning. In 1996, Dolly (sheep), Dolly the sheep became famous for being the first successful case of the reproductive cloning of a mammal. 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 foetal nuclei. "Therapeutic cloning" refers to the potential use of SCNT in regenerative medicine; this approach has been championed as an answer to the many Stem cell controversy, issues concerning embryonic stem cells (ESCs) and the destruction of viable embryos for medical use, though questions remain on how Sequence homology, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloning Diagram English
Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of cells and of DNA fragments. The artificial cloning of organisms, sometimes known as reproductive cloning, is often accomplished via somatic-cell nuclear transfer (SCNT), a cloning method in which a viable embryo is created from a somatic cell and an egg cell. In 1996, Dolly the sheep achieved notoriety for being the first mammal cloned from a somatic cell. Another example of artificial cloning is molecular cloning, a technique in molecular biology in which a single living cell is used to clone a large population of cells that contain identical DNA molecules. In bioethics, there are a variety of ethical positions rega ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryonic Stem Cells
Embryonic stem cells (ESCs) are Cell potency#Pluripotency, pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-Implantation (human embryo), implantation embryo. Human embryos reach the blastocyst stage 4–5 days post Human fertilization, fertilization, at which time they consist of 50–150 cells. Isolating the inner cell mass (embryoblast) using immunosurgery results in destruction of the blastocyst, a process Stem cell controversy, which raises ethical issues, including whether or not embryos at the pre-implantation stage have the same moral considerations as embryos in the post-implantation stage of development. Researchers are currently focusing heavily on the therapeutic potential of embryonic stem cells, with clinical use being the goal for many laboratories. Potential uses include the treatment of diabetes and heart disease. The cells are being studied to be used as clinical therapies, models of genetic disorders, and cellular/DNA r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parkinson's Disease
Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become more prevalent as the disease progresses. The motor symptoms are collectively called parkinsonism and include tremors, bradykinesia, spasticity, rigidity as well as postural instability (i.e., difficulty maintaining balance). Non-motor symptoms develop later in the disease and include behavior change (individual), behavioral changes or mental disorder, neuropsychiatric problems such as sleep abnormalities, psychosis, anosmia, and mood swings. Most Parkinson's disease cases are idiopathic disease, idiopathic, though contributing factors have been identified. Pathophysiology involves progressive nerve cell death, degeneration of nerve cells in the substantia nigra, a midbrain region that provides dopamine to the basal ganglia, a system invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryonic Stem Cells
Embryonic stem cells (ESCs) are Cell potency#Pluripotency, pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-Implantation (human embryo), implantation embryo. Human embryos reach the blastocyst stage 4–5 days post Human fertilization, fertilization, at which time they consist of 50–150 cells. Isolating the inner cell mass (embryoblast) using immunosurgery results in destruction of the blastocyst, a process Stem cell controversy, which raises ethical issues, including whether or not embryos at the pre-implantation stage have the same moral considerations as embryos in the post-implantation stage of development. Researchers are currently focusing heavily on the therapeutic potential of embryonic stem cells, with clinical use being the goal for many laboratories. Potential uses include the treatment of diabetes and heart disease. The cells are being studied to be used as clinical therapies, models of genetic disorders, and cellular/DNA r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem Cell Research
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can change into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of cell in a cell lineage. They are found in both embryonic and adult organisms, but they have slightly different properties in each. They are usually distinguished from progenitor cells, which cannot divide indefinitely, and precursor or blast cells, which are usually committed to differentiating into one cell type. In mammals, roughly 50 to 150 cells make up the inner cell mass during the blastocyst stage of embryonic development, around days 5–14. These have stem-cell capability. ''In vivo'', they eventually differentiate into all of the body's cell types (making them pluripotent). This process starts with the differentiation into the three germ layers – the ectoderm, mesoderm and endoderm – at the gastrulation stage. However, when th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytohaemagglutinin
Phytohaemagglutinin (PHA, or phytohemagglutinin) is a lectin found in plants, especially certain legumes. PHA actually consists of two closely related proteins, called leucoagglutinin (PHA-L) and PHA-E. These proteins cause blood cells to clump together. PHA-E cause erythrocytes (red blood cells) to clump. PHA-L causes leukocytes (white blood cells) to clump. Phytohaemagglutinin has carbohydrate-binding specificity for a complex oligosaccharide containing galactose, ''N''-acetylglucosamine, and mannose. It is found in the highest concentrations in uncooked red kidney beans and white kidney beans (also known as cannellini), and it is also found in lower quantities in many other types of green beans and other common beans (''Phaseolus vulgaris''), as well as broad beans (''Vicia faba'') such as fava beans. It has a number of physiological effects and is used in medical research. In high doses, it is a toxin. The lectin has a number of effects on cell metabolism; it induces mitos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zona Pellucida
The ''zona pellucida'' (Latin meaning "transparent zone") is the specialized area surrounding mammalian oocytes (eggs). It is also known as an egg coat. The ''zona pellucida'' is essential for oocyte growth and fertilization. The ''zona pellucida'' is an extracellular matrix that surrounds the plasma membrane of the egg cell. It helps protect the egg, and has an essential role in fertilization by sperm. It is surrounded by the corona radiata. The corona is composed of cells that care for the egg when it is emitted from the ovary. Structure The zona pellucida is a translucent matrix of cross-linked glycoprotein filaments that surrounds the mammalian oocyte and is 6.5–20 μm thick depending on the species. Its formation, which depends on a conserved zona pellucida-like (ZP) module that mediates the polymerization of egg coat components, is critical to successful fertilization. In non-mammals, it is called the vitelline membrane or vitelline envelope. Function The thick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micromanipulator
A micromanipulator is a device which is used to physically interact with a sample under a microscope, where a level of precision of movement is necessary that cannot be achieved by the unaided human hand. It may typically consist of an input joystick, a mechanism for reducing the range of movement and an output section with the means of holding a microtool to hold, inject, cut or otherwise manipulate the object as required. The mechanism for reducing the movement usually requires the movement to be free of backlash. This is achieved by the use of kinematic constraints to allow each part of the mechanism to move only in one or more chosen degrees of freedom, which achieves a high precision and repeatability of movement, usually at the expense of some absolute accuracy. Movement Movement reduction can be performed by mechanical levers, hydraulically using pistons of different diameters connected by tubing containing non-compressible fluid, electronically using stepper motors or lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blastocyst
The blastocyst is a structure formed in the early embryonic development of mammals. It possesses an inner cell mass (ICM) also known as the ''embryoblast'' which subsequently forms the embryo, and an outer layer of trophoblast cells called the trophectoderm. This layer surrounds the inner cell mass and a fluid-filled cavity or lumen known as the blastocoel. In the late blastocyst, the trophectoderm is known as the trophoblast. The trophoblast gives rise to the chorion and amnion, the two fetal membranes that surround the embryo. The placenta derives from the embryonic chorion (the portion of the chorion that develops villi) and the underlying uterine tissue of the mother. The corresponding structure in non-mammalian animals is an undifferentiated ball of cells called the blastula. In humans, blastocyst formation begins about five days after fertilization when a fluid-filled cavity opens up in the morula, the early embryonic stage of a ball of 16 cells. The blastocyst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reprogramming
In biology, reprogramming refers to erasure and remodeling of epigenetic marks, such as DNA methylation, during mammalian development or in cell culture. Such control is also often associated with alternative covalent modifications of histones. Reprogrammings that are both large scale (10% to 100% of epigenetic marks) and rapid (hours to a few days) occur at three life stages of mammals. Almost 100% of epigenetic marks are reprogrammed in two short periods early in development after fertilization of an ovum by a sperm. In addition, almost 10% of DNA methylations in neurons of the hippocampus can be rapidly altered during formation of a strong fear memory. After fertilization in mammals, DNA methylation patterns are largely erased and then re-established during early embryonic development. Almost all of the methylations from the parents are erased, first during early embryogenesis, and again in gametogenesis, with demethylation and remethylation occurring each time. Demethy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ECM 2001 Hybridoma System
ECM may refer to the following: Economics and commerce * Engineering change management * Equity capital markets * Error correction model, an econometric model * European Common Market Mathematics * Lenstra's Elliptic curve method for factoring integers * European Congress of Mathematics * Equivalent circuit model for Li-ion cells Science and medicine * Ectomycorrhiza * Electron cloud model * Engineered Cellular Magmatics * Erythema chronicum migrans * Extracellular matrix Sport * European Championships Management Technology * Electrochemical machining * Electronic contract manufacturing * Electronic countermeasure * Electronics contract manufacturing * Electronically commutated motor * Energy conservation measure * Engine control module * Enterprise content management * Error correction mode Other uses * East Camberwell railway station, Melbourne * ECM Records, a record label * ECM Real Estate Investments, a defunct real estate developer based in Luxemb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Leopard Frog
''Lithobates pipiens''Integrated Taxonomic Information System [Internet] 2012''Lithobates pipiens''[updated 2012 Sept; cited 2012 Dec 26] Available from: www.itis.gov/ formerly ''Rana pipiens'', commonly known as the northern leopard frog, is a species of leopard frog from the true frog Family (biology), family, native to parts of Canada and the United States. It is the List of U.S. state amphibians, state amphibian of Minnesota and Vermont. Description The northern leopard frog is a fairly large species of frog, reaching about in snout-to-vent length. It varies from green to brown in Dorsum (biology), dorsal color, with large, dark, circular spots on its back, sides, and legs.Northern Leopard Frog ''Rana pipiens'' National Geographi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
