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Ductal Cells
Ductal cells refer to the Epithelium, epithelial cell lining of the pancreatic duct that deliver enzymes from the Acinus, acinar cells to the duodenum. They have the essential function of producing bicarbonate-rich (HCO3-) secretion to neutralize stomach acidity. The hormone secretin stimulates ductal cells and is responsible for maintaining the duodenal pH and preventing duodenal injury from acidic chyme. Ductal cells mix their production with acinar cells to make up the pancreatic juice. Ductal cells comprise about 10% of the pancreas by number and about 4% in volume. Its function is to secrete bicarbonate and Mucin, mucins and to form the tubule network that transfers enzymes made by acinar cells to the duodenum. Ductal cells have a proliferation rate of about 0.5% in normal adults, but Mitosis, mitotic activity goes up when the pancreas is damaged. Ductal network The ductal pancreas network originates from the central pancreatic duct—this main duct with the bile duct opens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelium
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellular matrix. Epithelial tissues line the outer surfaces of organs and blood vessels throughout the body, as well as the inner surfaces of cavities in many internal organs. An example is the epidermis, the outermost layer of the skin. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either squamous, columnar, or cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified due to the placement of the nuclei. This sort of tissue is called pseudostratified. All glands are made up of epithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratified Cuboidal Epithelium
Stratified cuboidal epithelium is a type of epithelial tissue composed of multiple layers of cube-shaped cells. Only the most superficial layer is made up of cuboidal cells, and the other layers can be cells of other types. Topmost layer of skin epidermis in frogs, fishes is made up of living cuboidal cells. Structure This type of tissue can be observed in sweat glands, mammary glands, circumanal glands, and salivary glands. They protect areas such as the ducts of sweat glands, mammary glands, and salivary glands. They are also observed in the linings of urethra The urethra (from Greek οὐρήθρα – ''ourḗthrā'') is a tube that connects the urinary bladder to the urinary meatus for the removal of urine from the body of both females and males. In human females and other primates, the urethra c .... References External links Overview at umdnj.edu* "Sweat Duct" (Stratified cuboidal) * - "Skin" {{Authority control Epithelium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterial Morphological Plasticity
Bacterial morphological plasticity refers to changes in the shape and size that bacterial cells undergo when they encounter stressful environments. Although bacteria have evolved complex molecular strategies to maintain their shape, many are able to alter their shape as a survival strategy in response to protist predators, antibiotics, the immune response, and other threats. Bacterial shape and size under selective forces Normally, bacteria have different shapes and sizes which include coccus, rod and helical/spiral (among others less common) and that allow for their classification. For instance, rod shapes may allow bacteria to attach more readily in environments with shear stress (e.g., in flowing water). Cocci may have access to small pores, creating more attachment sites per cell and hiding themselves from external shear forces. Spiral bacteria combine some of the characteristics cocci (small footprints) and of filaments (more surface area on which shear forces can act) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transdifferentiation
Transdifferentiation, also known as lineage reprogramming, is the process in which one mature somatic cell is transformed into another mature somatic cell without undergoing an intermediate pluripotent state or progenitor cell type. It is a type of metaplasia, which includes all cell fate switches, including the interconversion of stem cells. Current uses of transdifferentiation include disease modeling and drug discovery and in the future may include gene therapy and regenerative medicine. The term 'transdifferentiation' was originally coined by Selman and Kafatos in 1974 to describe a change in cell properties as cuticle producing cells became salt-secreting cells in silk moths undergoing metamorphosis. Discovery Davis et al. 1987 reported the first instance (sight) of transdifferentiation where a cell changed from one adult cell type to another. Forcing mouse embryonic fibroblasts to express MyoD was found to be sufficient to turn those cells into myoblasts. Natural examples ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocrine Cell
The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neural control center for all endocrine systems. In humans, the major endocrine glands are the thyroid gland and the adrenal glands. The study of the endocrine system and its disorders is known as endocrinology. Glands that signal each other in sequence are often referred to as an axis, such as the hypothalamic-pituitary-adrenal axis. In addition to the specialized endocrine organs mentioned above, many other organs that are part of other body systems have secondary endocrine functions, including bone, kidneys, liver, heart and gonads. For example, the kidney secretes the endocrine hormone erythropoietin. Hormones can be amino acid complexes, steroids, eicosanoids, leukotrienes, or prostaglandins. The endocrine system can be contrasted to bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancreatic Duct
The pancreatic duct, or duct of Wirsung (also, the major pancreatic duct due to the existence of an accessory pancreatic duct), is a duct joining the pancreas to the common bile duct. This supplies it with pancreatic juice from the exocrine pancreas, which aids in digestion. Structure The pancreatic duct joins the common bile duct just prior to the ampulla of Vater, after which both ducts perforate the medial side of the second portion of the duodenum at the major duodenal papilla. There are many anatomical variants reported, but these are quite rare. Accessory pancreatic duct Most people have just one pancreatic duct. However, some have an additional accessory pancreatic duct, also called the Duct of Santorini. An accessory pancreatic duct can be functional or non-functional. It may open separately into the second part of the duodenum,Moore KL, Dalley AF. 2006. Clinically Oriented Anatomy. 5th Ed. Lippincott Williams & Wilkins. p 287.1. Mchonde GJ, Gesase AP. Termination patt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ductal System Of The Exocrine Pancreas By Phase Contrast (40759036833)
Lafarge is a French industrial company specialising in cement, construction aggregates, and concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wi .... It is the world's largest cement manufacturer. It was founded in 1833 by Joseph-Auguste Pavin de Lafarge and is a part of the Holcim Group. In 2015, Lafarge merged with Holcim and a new company was formed under the name of LafargeHolcim. It was renamed to Holcim Group in 2021. Lafarge was convicted of financing terrorism and complicity in crimes against humanity for paying $5.92 million to the terrorist groups Islamic State, ISIS and al Nusra Front between 2013 and 2014 to keep its cement plant in Syria operating. History Foundation and development Lafarge was founded in 1833 by Joseph-Auguste Pavin de Lafarge in Le Teil, Fran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microtubule
Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 and 15 nm. They are formed by the polymerization of a dimer of two globular proteins, alpha and beta tubulin into protofilaments that can then associate laterally to form a hollow tube, the microtubule. The most common form of a microtubule consists of 13 protofilaments in the tubular arrangement. Microtubules play an important role in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cilium
The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projection that extends from the surface of the much larger cell body. Eukaryotic flagella found on sperm cells and many protozoans have a similar structure to motile cilia that enables swimming through liquids; they are longer than cilia and have a different undulating motion. There are two major classes of cilia: ''motile'' and ''non-motile'' cilia, each with a subtype, giving four types in all. A cell will typically have one primary cilium or many motile cilia. The structure of the cilium core called the axoneme determines the cilium class. Most motile cilia have a central pair of single microtubules surrounded by nine pairs of double microtubules called a 9+2 axoneme. Most non-motile cilia have a 9+0 axoneme that lacks the central pair o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myoepithelial Cell
Myoepithelial cells (sometimes referred to as myoepithelium) are cells usually found in glandular epithelium as a thin layer above the basement membrane but generally beneath the luminal cells. These may be positive for alpha smooth muscle actin and can contract and expel the secretions of exocrine glands. They are found in the sweat glands, mammary glands, lacrimal glands, and salivary glands. Myoepithelial cells in these cases constitute the basal cell layer of an epithelium that harbors the epithelial progenitor. In the case of wound healing, myoepithelial cells reactively proliferate. Presence of myoepithelial cells in a hyperplastic tissue proves the benignity of the gland and, when absent, indicates cancer. Only rare cancers like adenoid cystic carcinomas contains myoepithelial cells as one of the malignant component. It can be found in endoderm or ectoderm. Markers Myoepithelial cells are true epithelial cells positive for keratins, not to be confused with myofibr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goblet Cell
Goblet cells are simple columnar epithelial cells that secrete gel-forming mucins, like mucin 5AC. The goblet cells mainly use the merocrine method of secretion, secreting vesicles into a duct, but may use apocrine methods, budding off their secretions, when under stress. The term ''goblet'' refers to the cell's goblet-like shape. The apical portion is shaped like a cup, as it is distended by abundant mucus laden granules; its basal portion lacks these granules and is shaped like a stem. The goblet cell is highly polarized with the nucleus and other organelles concentrated at the base of the cell and secretory granules containing mucin, at the apical surface. The apical plasma membrane projects short microvilli to give an increased surface area for secretion. Goblet cells are typically found in the respiratory, reproductive and gastrointestinal tracts and are surrounded by other columnar cells. Biased differentiation of airway basal cells in the respiratory epithelium, into gobl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basolateral Membrane
Epithelial polarity is one example of the cell polarity that is a fundamental feature of many types of cells. Epithelial cells feature distinct 'apical', 'lateral' and 'basal' plasma membrane domains. Epithelial cells connect to one another via their lateral membranes to form epithelial sheets that line cavities and surfaces throughout the animal body. Each plasma membrane domain has a distinct protein composition, giving them distinct properties and allowing directional transport of molecules across the epithelial sheet. How epithelial cells generate and maintain polarity remains unclear, but certain molecules have been found to play a key role. A variety of molecules are located at the apical membrane, but only a few key molecules act as determinants that are required to maintain the identity of the apical membrane and, thus, epithelial polarity. These molecules are the proteins Cdc42, atypical protein kinase C (aPKC), Par6, Par3/Bazooka/ASIP. Crumbs, "Stardust" and protei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_and_foveolar_cells_in_incomplete_Barrett's_esophagus.jpg "Click for more on -> Goblet Cell")