"is therefore a component of several radiographic classifications of osteoarthritis. Synovial joint A synovial joint, also known as diarthrosis, joins bones with a fibrous joint capsule that is continuous with the periosteum of the joined bones, constitutes the outer boundary of a synovial cavity, and surrounds the bones' articulating surfaces. The synovial cavity/joint is filled with synovial fluid. The joint capsule is made up of an outer layer, the articular capsule, which keeps the bones together structurally, and an inner layer, the synovial membrane, which seals in the synovial fluid. They are the most common and most movable type of"
"(so-called ""weeping lubrication""). The functions of the synovial fluid include: Synovial tissue is sterile and composed of vascularized connective tissue that lacks a basement membrane. Two cell types (type A and type B) are present: Type A is derived from blood monocytes, and it removes the wear-and-tear debris from the synovial fluid. Type B produces hyaluronan. Synovial fluid is made of hyaluronic acid and lubricin, proteinases, and collagenases. Synovial fluid exhibits non-Newtonian flow characteristics; the viscosity coefficient is not a constant and the fluid is not linearly viscous. Synovial fluid has rheopexy characteristics; viscosity increases and the fluid thickens over"
"it is a less effective lubricant of the cartilage surfaces. Under stimulation from invading inflammatory cells, the synovial cells may also produce enzymes (proteinases) that can digest the cartilage extracellular matrix. Fragments of extracellular matrix can then further irritate the synovium. The word ""synovium"" is related to the word ""synovia"" in its sense meaning ""synovial fluid"". The latter was coined by Paracelsus. More information is given at ""Synovial fluid § Etymology and pronunciation"". Synovial membrane The synovial membrane (also known as the synovial stratum, synovium or stratum synoviale) is a specialized connective tissue that lines the inner surface of capsules"
"major salivary glands produce mixed (serous and mucus) saliva. Another type of serous fluid is secreted by the serous membranes (serosa), two-layered membranes which line the body cavities. Serous membrane fluid collects on microvilli on the outer layer and acts as a lubricant and reduces friction from muscle movement. This can be seen in the lungs, with the pleural cavity. Blood serum is the component of blood that is neither a blood cell, nor a clotting factor. Blood serum and blood plasma are similar, but serum does not contain any clotting factors, such as fibrinogen, prothrombin, thromboplastin and many others."
"the skeleton. Together, these fibrous layers, along with tendons and ligaments, constitute the deep fascia of the body. Movement is not limited to only synovial joints, although they allow for most freedom. Muscles also run over symphysis, which allow for movement in for example the vertebral column by compression of the intervertebral discs. Additionally, synovial joints can be divided into different types, depending on their axis of movement. A serous membrane (also referred to as a serosa) is a thin membrane that covers the walls of organs in the thoracic and abdominal cavities. The serous membranes have two layers; ""parietal"""
"head and neck of excess interstitial fluid via lymph vessels or capillaries, equally into the right lymphatic duct and the thoracic duct. Lymph nodes line the cervical spine and neck regions as well as along the face and jaw. The tonsils also are lymphatic tissue and help mediate the ingestion of pathogens. Tonsils in humans include, from superior to inferior: nasopharyngeal tonsils (also known as adenoids), palatine tonsils, and lingual tonsils. Together this set of lymphatic tissue is called the tonsillar ring or Waldeyer's ring. The spinal nerves arise from the spinal column. The top section of the spine is"
"more articular heads; amphiarthrosis, which is a joint that allows ""some"" movement, and false joints or synarthroses, joints that are immovable, that allow little or no movement and are predominantly fibrous. Synovial joints, joints that are not directly joined, are lubricated by a solution called synovial fluid that is produced by the synovial membranes. This fluid lowers the friction between the articular surfaces and is kept within an articular capsule, binding the joint with its taut tissue. A ligament is a small band of dense, white, fibrous elastic tissue. Ligaments connect the ends of bones together in order to form"
"to maintain proper joint function by providing the structural support and supply of the necessary nutrients to the surrounding cartilage. Synovial membrane is divided into two compartments – the outer layer (subintima) and the inner layer (intima). The inner layer is mainly composed of two cell types, specialized macrophages (macrophage-like synovial cells) and fibroblast-like synoviocytes, which are important in maintaining the internal joint homeostasis. These cells represent the main source of hyaluronic acid and also other glycoproteins, major components of the synovial fluid. Fibroblast-like synoviocytes are cells of mesenchymal origin that display many characteristics common with fibroblasts, such as expression"
"the composition of the blood. Two of these sites, the SFO (subfornical organ) and the OVLT (organum vasculosum of the lamina terminalis) are so-called circumventricular organs, where neurons are in intimate contact with both blood and CSF. These structures are densely vascularized, and contain osmoreceptive and sodium-receptive neurons that control drinking, vasopressin release, sodium excretion, and sodium appetite. They also contain neurons with receptors for angiotensin, atrial natriuretic factor, endothelin and relaxin, each of which important in the regulation of fluid and electrolyte balance. Neurons in the OVLT and SFO project to the supraoptic nucleus and paraventricular nucleus, and also"
"contains a lubricating fluid. as it reaches the 4th rib – atria 8th rib – mid clavicular 10th rib – axillary area 12th rib – back side The parietal pleura is supplied by the intercostal nerves and the phrenic nerve. The costal pleura is innervated by the intercostal nerves. The diaphragmatic portion of the parietal pleura overlies the diaphragm and is innervated by the phrenic nerve in its central portion and by the intercostal nerves in its peripheral portion. The mediastinal portion of the parietal pleura forms the lateral wall of the mediastinum and is innervated by the phrenic nerve."
"a large glycoprotein that consists of approximately equal proportions of protein and oligosaccharides. The oligosaccharides are ""O""-linked both with and without sialic acid.. Electron microscope measurements show that the lubricin molecule is a partially extended flexible rod and, in solution, occupies a smaller spatial domain than would be expected from structural predictions. The large glycosylated region (i. e mucin domain) of lubricin makes it a water-soluble synovial fluid protein. In synovial fluid it interacts with Galectin-3 that improves its lubricating property. Lubricins unglycosylated regions can interact cartilage proteins. This characteristic may aid in the molecule's boundary lubricating ability. Lubricin, as"
"Saliva Saliva is a fluid substance formed in the mouths of animals, secreted by the salivary glands. Human saliva comprises 99.5% water plus electrolytes, mucus, white blood cells, epithelial cells (from which DNA can be extracted), enzymes (such as amylase and lipase), antimicrobial agents such as secretory IgA and lysozyme. The enzymes found in saliva are essential in beginning the process of digestion of dietary starches and fats. These enzymes also play a role in breaking down food particles entrapped within dental crevices, thus protecting teeth from bacterial decay. Saliva also performs a lubricative function, wetting food and permitting the"
"the sternoclavicular joint. The disc divides each joint into two compartments, the lower and upper compartments. These two compartments are synovial cavities, which consists of an upper and a lower synovial cavity. The synovial membrane lining the joint capsule produces the synovial fluid that fills these cavities. The central area of the disc is avascular and lacks innervation, thus getting its nutrients from the surrounding synovial fluid. In contrast, the posterior ligament and the surrounding capsules along has both blood vessels and nerves. Few cells are present, but fibroblasts and white blood cells are among these. The central area is"
"well as the corneal endothelium. Sodium hyaluronate functions as a tissue lubricant and is thought to play an important role in modulating the interactions between adjacent tissues. It forms a viscoelastic solution in water. Mechanical protection for tissues (iris, retina) and cell layers (corneal, endothelium, and epithelium) are provided by the high viscosity of the solution. Elasticity of the solution assists in absorbing mechanical stress and providing a protective buffer for tissues. In facilitating wound healing, it is thought that it acts as a protective transport vehicle, taking peptide growth factors and other structural proteins to a site of action."
"also suggested that undesirable contents within the synovial fluid of the joint can be washed out, such as microscopic debris (from breakdown of the articular surfaces) and pain mediators (enzymes and prostaglandins), and there is also stimulation of the synovial membrane to restore its normal lubricating function. It was initially used to treat acute closed lock, however it has since come to be used chronic closed lock, chronic anterior displaced disc with reduction, and degenerative joint disease (e.g. arthritis). In acute closed lock, it is theorized that the upper joint space is inflated from its normally collapsed state during this"
"thin fluid coating within all alveoli. The fluid coating is produced by the body in order to facilitate the transfer of gases between blood and alveolar air. The surfactant is produced by the type II cells which are the most numerous cells in the alveoli, yet do not cover as much surface area as the squamous alveolar cells (a squamous epithelium). Type II cells also repair the endothelium of the alveolus when it becomes damaged. Insufficient surfactant in the alveoli can contribute to atelectasis (collapse of part or all of the lung). Without pulmonary surfactant, atelectasis is a certainty; however,"
"Fibroblast-like synoviocyte Fibroblast-like synoviocytes (FLS) represent a specialised cell type located inside joints in the synovium. These cells play a crucial role in the pathogenesis of chronic inflammatory diseases, such as rheumatoid arthritis. The inner lining of the joint consists of the synovium (also called the synovial membrane), a thin layer located between the joint capsule and the joint cavity. The word ""synovium"" is derived from the word ""synovia"" (or synovial fluid), which is a clear, viscous fluid produced by the synovium, and its main purpose is to reduce friction between the joint cartilages during movement. Synovium is also important"
"Liver sinusoid A liver sinusoid is a type of capillary known as a sinusoid capillary, or ""discontinuous capillary"" that is similar to a fenestrated capillary, having discontinuous endothelium that serves as a location for mixing of the oxygen-rich blood from the hepatic artery and the nutrient-rich blood from the portal vein. The liver sinusoid has a larger caliber than other types of capillaries and has a lining of specialised endothelial cells known as the liver sinusoidal endothelial cells (LSECs), and Kupffer cells. The cells are porous and have a scavenging function. The LSECs make up around half of the non-parenchymal"
"parts of the body may also have specific names for these structures. For example, the serosa of the uterus is called the perimetrium. The pericardial cavity (surrounding the heart), pleural cavity (surrounding the lungs) and peritoneal cavity (surrounding most organs of the abdomen) are the three serous cavities within the human body. While serous membranes have a lubricative role to play in all three cavities, in the pleural cavity it has a greater role to play in the function of breathing. The serous cavities are formed from the intraembryonic coelom and are basically an empty space within the body surrounded"
"Splenic vein The splenic vein (formerly the lienal vein) is a blood vessel that drains blood from the spleen, the stomach fundus and part of the pancreas. It is part of the hepatic portal system. The splenic vein is formed when several smaller collectors leaving the spleen join shortly thereafter. It follows a course superior to the pancreas, alongside the splenic artery. It collects branches from the stomach and pancreas, and most notably from the large intestine (also drained by the superior mesenteric vein) via the inferior mesenteric vein, which drains in the splenic vein shortly before the origin of"
"and spinal cord are protected by the bones of the skull and vertebral column and by cerebrospinal fluid, a colorless fluid produced by the brain, which cushions the brain and spinal cord within the posterior (dorsal) cavity. The thoracic cavity consists of three cavities that fill the interior area of the chest. The diaphragm divides the thoracic and the abdominal cavities. The abdominal cavity occupies the entire lower half of the trunk, anterior to the spine. Just under the abdominal cavity, anterior to the buttocks, is the pelvic cavity. The pelvic cavity is funnel shaped and is located inferior and"
"one another. The mesothelium is composed of an extensive monolayer of specialized cells (mesothelial cells) that line the body's serous cavities and internal organs. The main purpose of these cells is to produce a lubricating fluid that is released between layers, providing a slippery, non-adhesive, and protective surface to facilitate intracoelomic movement. The mesothelium is also implicated in the transport and movement of fluid and particulate matter across the serosal cavities, leukocyte migration in response to inflammatory mediators, synthesis of pro-inflammatory cytokines, growth factors, and extracellular matrix proteins to aid in serosal repair, and the release of factors to promote"
"contain nerve endings, which may cause pain if damaged. The blood supply of the labrum has also been demonstrated. The joint itself is encompassed by a thick, fibrous joint capsule, which is lined by synovium. The ligaments that keep the hip joint in place are in fact, thickened areas of joint capsule, rather than distinct structures. The synovium generates fluid that lubricates the joint; in that fluid are the nutrients needed to keep the cartilage cells alive. A total of 27 muscles cross the hip joint, making it a very deep part of the body for arthroscopic access. This is"
"also thinner but of denser consistency than the peripheral region, which is thicker but has a more cushioned consistency. The synovial fluid in the synovial cavities provides the nutrition for the avascular central area of the disc. With age, the entire disc thins and may undergo addition of cartilage in the central part, changes that may lead to impaired movement of the joint. The lower joint compartment formed by the mandible and the articular disc is involved in rotational movement—this is the initial movement of the jaw when the mouth opens. The upper joint compartment formed by the articular disc"
"Bursitis Bursitis is the inflammation of one or more bursae (small sacs) of synovial fluid in the body. They are lined with a synovial membrane that secretes a lubricating synovial fluid. There are more than 150 bursae in the human body. The bursae rest at the points where internal functionaries, such as muscles and tendons, slide across bone. Healthy bursae create a smooth, almost frictionless functional gliding surface making normal movement painless. When bursitis occurs, however, movement relying on the inflamed bursa becomes difficult and painful. Moreover, movement of tendons and muscles over the inflamed bursa aggravates its inflammation, perpetuating"
"synovial fluid began around 1940 using cadaver-derived fluid and comparing characteristics to those of, for instance, bovine synovial fluid. The mucin clot test is a very old approach to determining if an inflammatory infiltrate is present. In this test, acetic acid is added to the synovial fluid specimen. In a normal specimen, this should lead to a congealing of the hyaluronic acid, forming a 'mucin clot.' If inflammation is present, a mucin clot is not formed (the hyaluronic acid is degraded). Lactate is elevated in septic arthritis, usually above 250 mg/dL. Complement factors are decreased in rheumatoid arthritis and lupus"
"directly connect two capillary beds. Examples of such systems include the hepatic portal vein and hypophyseal portal system. The peripheral veins carry blood from the limbs and hands and feet. Microscopically, veins have a thick outer layer made of connective tissue, called the tunica externa or ""tunica adventitia"". There is a middle layer of bands of smooth muscle called tunica media, which are, in general, much thinner than those of arteries, as veins do not function primarily in a contractile manner and are not subject to the high pressures of systole, as arteries are. The interior is lined with endothelial"
"responsible for the absorption of interstitial fluid from the tissues, while lymph vessels propel the absorbed fluid forward into the larger collecting ducts, where it ultimately returns to the bloodstream via one of the subclavian veins. These vessels are also called the lymphatic channels or simply ""lymphatics"". The lymphatics are responsible for maintaining the balance of the body fluids. Its network of capillaries and collecting lymphatic vessels work to efficiently drain and transport extravasated fluid, along with proteins and antigens, back to the circulatory system. Numerous intraluminal valves in the vessels ensure a unidirectional flow of lymph without reflux. Two"
"Synovectomy Synovectomy is a procedure where the synovial tissue surrounding a joint is removed. This procedure is typically recommended to provide relief from a condition in which the synovial membrane or the joint lining becomes inflamed and irritated and is not controlled by medication alone. If arthritis (inflammation of the joint) is not controlled, it can lead to irreversible joint damage. The synovial membrane or ""synovium"" encloses each joint and also secretes a lubricating fluid that allows different joint motions such as rolling, folding and stretching. When the synovium becomes inflamed or irritated, it increases fluid production, resulting in warmth,"
"skin provides containment, structure, and protection for other organs, and serves as a major sensory interface with the outside world. The lymphatic system extracts, transports and metabolizes lymph, the fluid found in between cells. The lymphatic system is similar to the circulatory system in terms of both its structure and its most basic function, to carry a body fluid. The musculoskeletal system consists of the human skeleton (which includes bones, ligaments, tendons, and cartilage) and attached muscles. It gives the body basic structure and the ability for movement. In addition to their structural role, the larger bones in the body"
"Vascular organ of lamina terminalis The vascular organ of lamina terminalis (VOLT), organum vasculosum of the lamina terminalis (OVLT), or supraoptic crest is one of the four sensory circumventricular organs of the brain, the others being the subfornical organ, the median eminence, and the area postrema in the brainstem. The VOLT, median eminence, and subfornical organ are interconnected with the mid-ventral hypothalamus, and together these three structures surround the third ventricle, a complex often called the ""AV3V"" region. This region functions in the regulation of fluid and electrolyte balance by controlling thirst, sodium excretion, blood volume regulation, and vasopressin secretion."
"The submandibular gland's highly active acini account for most of the salivary volume. The parotid and sublingual glands account for the remaining. The gland receives its blood supply from the facial and lingual arteries. The gland is supplied by sublingual and submental arteries and drained by common facial and lingual veins. The lymphatics from submandibular gland first drain into submandibular lymph nodes and subsequently into jugulo - digastric lymph nodes. Their secretions, like the secretions of other salivary glands, are regulated ""directly"" by the parasympathetic nervous system and ""indirectly"" by the sympathetic nervous system. The submandibular salivary glands develop later"
"mandatory which is a huge problem for many countries today. The great saphenous vein,(GSV) a superficial vein, is the longest vein in the body. It has its origin in the dorsal venous arch of the foot, a superficial vein which connects the small saphenous vein with the GSV. It travels up the leg and medial side of the thigh to reach the groin, where it drains into the common femoral vein. Along the length of the GSV, it receives numerous tributaries, (from the subcutaneous layer) and drains into the deep veins via the perforator veins. When seen in a scan,"