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Mesenchymal Stem Cell
Mesenchymal stem cells (MSCs), also known as mesenchymal stromal cells or medicinal signaling cells, are multipotent stromal cells that can Cellular differentiation, differentiate into a variety of cell types, including osteoblasts (bone cells), chondrocytes (cartilage cells), myocytes (muscle cells) and adipocytes (fat cells which give rise to Marrow Adipose Tissue, marrow adipose tissue). The primary function of MSCs is to respond to injury and infection by secreting and recruiting a range of biological factors, as well as modulating inflammatory processes to facilitate tissue repair and regeneration. Extensive research interest has led to more than 80,000 peer-reviewed papers on MSCs. Structure Definition Mesenchymal stem cells (MSCs), a term first used (in 1991) by Arnold Caplan at Case Western Reserve University, are characterized morphologically by a small cell body with long, thin cell processes. While the terms ''mesenchymal stem cell'' (MSC) and ''marrow stromal cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission Electron Microscopy
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a detector such as a scintillator attached to a charge-coupled device or a direct electron detector. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesoderm
The mesoderm is the middle layer of the three germ layers that develops during gastrulation in the very early development of the embryo of most animals. The outer layer is the ectoderm, and the inner layer is the endoderm.Langman's Medical Embryology, 11th edition. 2010. The mesoderm forms mesenchyme, mesothelium and coelomocytes. Mesothelium lines coeloms. Mesoderm forms the muscles in a process known as myogenesis, septa (cross-wise partitions) and mesenteries (length-wise partitions); and forms part of the gonads (the rest being the gametes). Myogenesis is specifically a function of mesenchyme. The mesoderm differentiates from the rest of the embryo through intercellular signaling, after which the mesoderm is polarized by an organizing center. The position of the organizing center is in turn determined by the regions in which beta-catenin is protected from degradation by GSK-3. Beta-catenin acts as a co-factor that alters the activity of the transcription facto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Mesenchymal Stem Cells
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing#Evolution of hairlessness, hairlessness, bipedality, bipedalism, and high Human intelligence, intelligence. Humans have large Human brain, brains, enabling more advanced cognitive skills that facilitate successful adaptation to varied environments, development of sophisticated tools, and formation of complex social structures and civilizations. Humans are Sociality, highly social, with individual humans tending to belong to a Level of analysis, multi-layered network of distinct social groups — from families and peer groups to corporations and State (polity), political states. As such, social interactions between humans have established a wide variety of Value theory, values, norm (sociology), social norms, languages, and traditions (co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pericyte
Pericytes (formerly called Rouget cells) are multi-functional mural cells of the microcirculation that wrap around the endothelial cells that line the capillaries throughout the body. Pericytes are embedded in the basement membrane of blood capillaries, where they communicate with endothelial cells by means of both direct physical contact and paracrine signaling. The morphology, distribution, density and molecular fingerprints of pericytes vary between organs and vascular beds. Pericytes help in the maintainenance of homeostatic and hemostatic functions in the brain, where one of the organs is characterized with a higher pericyte coverage, and also sustain the blood–brain barrier. These cells are also a key component of the neurovascular unit, which includes endothelial cells, astrocytes, and neurons. Pericytes have been postulated to regulate capillary blood flow and the clearance and phagocytosis of cellular debris ''in vitro.'' Pericytes stabilize and monitor the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perivascular Cell
Mural cells are the generalized name of cell population in the microcirculation that is comprised of vascular smooth muscle cells (vSMCs), and pericytes. Both types are in close contact with the endothelial cells lining the capillaries, and are important for vascular development and stability. The vasculature is a system of small, interconnected tubes that ensure there is proper blood flow to all of the organs.Mural cells are involved in the formation of normal vasculature and are responsive to factors including platelet-derived growth factor B (PDGFB) and vascular endothelial growth factor (VEGF). The weakness and disorganization of tumor vasculature is partly due to the inability of tumors to recruit properly organized mural cells. Function during angiogenesis Mural cells, like pericytes, are important for how blood vessels work. During the growth of new blood vessels (a process called angiogenesis), pericytes help guide how endothelial cells grow and divide. This process rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deciduous Teeth
Deciduous teeth or primary teeth, also informally known as baby teeth, milk teeth, or temporary teeth,Fehrenbach, MJ and Popowics, T. (2026). ''Illustrated Dental Embryology, Histology, and Anatomy'', 6th edition, Elsevier, page 287–296. are the first set of teeth in the growth and development of humans and other diphyodonts, which include most mammals but not elephants, kangaroos, or manatees, which are polyphyodonts. Deciduous teeth Animal tooth development, develop during the embryonic stage of development and tooth eruption, erupt (break through the gums and become visible in the mouth) during infancy. They are usually lost and replaced by permanent teeth, but in the absence of their permanent replacements, they can remain functional for many years into adulthood. Development Formation Primary teeth start to form during the embryonic phase of human development (biology), human life. The development of primary teeth starts at the sixth week of tooth development as the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stroma Of Cornea
The stroma of the cornea (or substantia propria) is a fibrous, tough, unyielding, perfectly transparent and the thickest layer of the cornea of the eye. It is between Bowman's layer anteriorly, and Descemet's membrane posteriorly. At its centre, a human corneal stroma is composed of about 200 flattened ''lamellae'' (layers of collagen fibrils), superimposed one on another. They are each about 1.5-2.5 μm in thickness. The anterior lamellae interweave more than posterior lamellae. The fibrils of each lamella are parallel with one another, but at different angles to those of adjacent lamellae. The lamellae are produced by keratocytes (corneal connective tissue cells), which occupy about 10% of the substantia propria. Apart from the cells, the major non-aqueous constituents of the stroma are collagen fibrils and proteoglycans. The collagen fibrils are made of a mixture of type I and type V collagens. These molecules are tilted by about 15 degrees to the fibril axis, and because ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contraction, contract. Muscle tissue contains special Muscle contraction, contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins, present are two regulatory proteins, troponin and tropomyosin. Muscle is formed during embryonic development, in a process known as myogenesis. Skeletal muscle tissue is striated consisting of elongated, multinucleate muscle cells called muscle fibers, and is responsible for movements of the body. Other tissues in skeletal muscle include tendons and perimysium. Smooth and cardiac muscle contract involuntarily, without conscious intervention. These muscle types may be activated both through the interaction of the central nervous system as well as by innervation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adipose Tissue
Adipose tissue (also known as body fat or simply fat) is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, Blood vessel, vascular endothelial cells and a variety of White blood cell, immune cells such as adipose tissue macrophages. Its main role is to store energy in the form of lipids, although it also cushions and Thermal insulation, insulates the body. Previously treated as being hormonally inert, in recent years adipose tissue has been recognized as a major endocrine organ, as it produces hormones such as leptin, estrogen, resistin, and cytokines (especially TNF-alpha, TNFα). In obesity, adipose tissue is implicated in the chronic release of pro-inflammatory markers known as adipokines, which are responsible for the development of metabolic syndromea constellation of diseases including type 2 diabetes, cardiovascular disease and atherosclerosis. Adipose tissue is d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilical Cord
In Placentalia, placental mammals, the umbilical cord (also called the navel string, birth cord or ''funiculus umbilicalis'') is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologically and genetically part of the fetus and (in humans) normally contains two arteries (the umbilical arteries) and one vein (the umbilical vein), buried within Wharton's jelly. The umbilical vein supplies the fetus with oxygenated, nutrient-rich blood from the placenta. Conversely, the fetal heart pumps low-oxygen, nutrient-depleted blood through the umbilical arteries back to the placenta. Structure and development The umbilical cord develops from and contains remnants of the yolk sac and allantois. It forms by the fifth week of human embryogenesis, development, replacing the yolk sac as the source of nutrients for the embryo. The cord is not directly connected to the mother's circulatory system, but instead joins the pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placenta
The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner. In humans, a thin layer of maternal decidual ( endometrial) tissue comes away with the placenta when it is expelled from the uterus following birth (sometimes incorrectly referred to as the 'maternal part' of the placenta). Placentas are a defining characteristic of placental mammals, but are also found in marsupials and some non-mammals with varying levels of development. Mammalian placentas probably first evolved abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
