Tumour Necrosis Factor: From 1 Different Sources
(TNF) either of two proteins, TNF-? or TNF-?, that function as *cytokines. Produced by macrophages, monocytes, T lymphocytes, and various other cells, they mediate many responses, including inflammation, and have a marked action against tumour cells. Anti-TNF drugs (see cytokine inhibitor) are used in the treatment of several disorders, especially rheumatoid arthritis and ankylosing spondylitis.
One of two proteins secreted from the lining of the stomach whose sole purpose is (it seems) to cradle B12 in a pre-fitted styrofoam mold and (A) carry it through the Seven Levels of Digestive Hell until it reaches those few absorption sites in the last foot of small intestine that understand its “Special Needs” (sounds either sexually kinky or the airplane dinner label on kosher food for flying Hassidim jewelers) and finally (B) slip it from one protein to the other, and thence into the cell membranes where its is turn handed over to (C) the specialized blood protein that can carry it safely to the final target tissues (3 times out of 4, the bone marrow). Cyanocobalamin (B12) has parts that fall off, radicals that twirl around in five directions on three charge potentials, and is as durable as a 49¢ water pistol. And, if we have an ulcer, chronic enteritis or long-standing steatorrhea, we either get B12 shots (and hope the liver still makes that blood carrier) or walk around with pernicious anemia and a hematocrit of 16.... intrinsic factor
Death of tissue or cells, either from infection or the loss of normal circulation and autotoxicity.... necrosis
An aspect of personal behaviour or lifestyle, an environmental exposure, or an inborn or inherited characteristic, which, on the basis of scientific evidence, is known to be associated with health-related condition(s) considered important to prevent.... risk factor
A mass or swelling. The lump can be a neoplasm (benign or malignant) or a tumour can be a mass due to an infection or inflammation.... tumour
A coagulative blood protein that is a constituent of the COAGULATION cascade – an essential component in the clotting of blood. Those people with the inherited disorder, HAEMOPHILIA, have abnormally low amounts of factor VIII and so bleed more when cut. They are treated with a concentrated version to reduce the tendency to bleed.... factor viii
See BLOOD GROUPS.... rh factor
See BLOOD GROUPS.... rhesus factor
Also called nephroblastoma. This is the commonest kidney tumour in infancy. It is a malignant tumour, which occurs in around one per 10,000 live births. The survival rate with modern treatment (removal of the kidney followed by radiotherapy and chemotherapy) is now around 80 per cent.... wilms’ tumour
A protein in blood that plays an important role in the clotting mechanism. A deficiency of factor causes a rare genetic bleeding disorder known as Christmas disease.... factor ix
A growth comprised of immature sperm cells in the male testis or of immature ova in the female ovary. A seminoma is one type of germ cell tumour (see testis, cancer of).... germ cell tumour
In injury to, or in?ammation of, the PANCREAS, the fat-splitting enzyme in it may escape into the abdominal cavity, causing death of fat-containing cells.... fat necrosis
A chemical, psychological, physiological, social, environmental or genetic factor or conditions that predisposes an individual to the development of a disease or injury.... health risk factor
The study of the interrelationships between humans, the tools they use, and the environment in which they live and work.... human-factor research
An agent involved in the clotting mechanism of the blood. It helps in the activation of THROMBOPLASTIN in the blood PLASMA (see COAGULATION).... lipoid factor
Various compounds and processes that enable the liver to metabolize fats properly or prevent the formation of cholesterolic stones in the gall bladder by supporting the continued emulsification of gall bladder bile. EXAMPLES: Lecithin, choline, Aristolochia... lipotropic factors
A neoplasm with a number of different cell types undergoing cancerous change.... mixed tumour
A growth composed of cells that produce various hormones. These cells, amine precursor uptake and decarboxylation (APUD) cells, occur in different parts of the body. Some tumours of the thyroid gland, pancreas, and lungs are cell tumours, as are a carcinoid tumour (see carcinoid syndrome) and phaeochromocytoma (a type of adrenal tumour).... apud cell tumour
See dermoid cyst.... dermoid tumour
Factors that lead to increased susceptibility to a disease.... predisposing factors
A growth arising from the tissues that develop into the placenta. The most common type of trophoblastic tumour is a hydatidiform mole. (See also choriocarcinoma.)... trophoblastic tumour
A type of kidney cancer, also called nephroblastoma, that occurs mainly in children.... wilms’ tumour
(ARN) severe inflammation and necrosis of the retina associated with inflammation and blockage of retinal blood vessels, haemorrhage and death of retinal tissue, and retinal detachment. It may affect both eyes (bilateral acute retinal necrosis, BARN), and visual prognosis is poor. ARN is thought to be due to viral infection.... acute retinal necrosis
(ATN) a condition caused by acute renal injury from either ischaemia or toxins and associated with tubular damage that is usually reversible. The earliest feature is *isosthenuria, which may occur while there is still a high urine flow rate. This is followed by a reduction in *glomerular filtration rate. *Oliguria is common and dialysis often needed for survival. If the cause of the initial damage can be removed, recovery of renal function within six weeks can be expected in most cases.... acute tubular necrosis
a group of *growth factors that promote new bone formation. Bone morphogenic protein (BMP), a naturally occurring substance that induces *osteoblast formation, has been genetically synthesized to form bone morphogenetic protein, which stimulates new bone formation and assists with fracture healing. Other bone growth factors include a type of transforming growth factor (TGF?) and insulin-like growth factor II (IGF-II), which encourage collagen formation.... bone growth factors
see coagulation factors.... clotting factors
(clotting factors) a group of substances present in blood plasma that, under certain circumstances, undergo a series of chemical reactions leading to the conversion of blood from a liquid to a solid state (see blood coagulation). Although they have specific names, most coagulation factors are referred to by an agreed set of Roman numerals (e.g. *Factor VIII, *Factor IX). Lack of any of these factors in the blood results in the inability of the blood to clot. See also haemophilia.... coagulation factors
(CSF) one of a group of substances (haemopoietic growth factors or hormones) that are produced in the bone marrow and stimulate the production of specific blood cells. Genetically engineered granulocyte colony-stimulating factor (G-CSF) stimulates neutrophil production and also limits bone marrow toxicity from chemotherapy.... colony-stimulating factor
an abnormal multiplication of brain cells. Any tumorous swelling tends to compress or even destroy the healthy brain cells surrounding it and – because of the rigid closed nature of the skull – increases the pressure on the brain tissue. Malignant brain tumours, which are much more common in children than in adults, include *medulloblastomas and *gliomas; these grow rapidly, spreading through the otherwise normal brain tissue and causing progressive neurological disability. Benign tumours, such as *meningiomas, grow slowly and compress the brain tissue. Both benign and malignant tumours commonly cause fits. Benign tumours are often cured by total surgical resection. Malignant tumours may be treated by neurosurgery, chemotherapy, and radiotherapy, but the outcome for most patients remains poor.... cerebral tumour
a rare tumour of fetal remnants of the ovaries or testes. In women it is an aggressive malignant ovarian tumour that develops in adolescence and may secrete alpha-fetoprotein and human chorionic gonadotrophin, which can be used as *tumour markers. It is treated by oophorectomy with adjuvant chemotherapy.... endodermal sinus tumour
(EGFR) a protein on the surface of cells (see receptor) that binds with epidermal *growth factor and is therefore involved in cell division. EGFR is expressed at increased levels in numerous tumours, particularly of the head and neck, and in colorectal cancer, in which it can be a target for antibody therapy with *cetuximab. *Tyrosine kinase inhibitors acting specifically on the EGFR include gefitinib and erlotinib in lung and pancreatic cancer.... epidermal growth factor receptor
n. (in biochemistry) a substance that is essential to a physiological process, often a substance the nature of which is unknown. See also coagulation factors; growth factor.... factor
an inherited mutation in the gene coding for coagulation Factor V, which results in an increased susceptibility to develop venous *thrombosis.... factor v leiden
a *coagulation factor normally present in blood. Deficiency of the factor is inherited, but rarely causes spontaneous bleeding. However, bleeding does occur after surgery or trauma to the blood vessels.... factor xi
(GIST) a rare type of sarcoma arising from the gastrointestinal tract (usually the stomach), characterized by the presence of the receptor c-kit/CD117 on the surface of the tumour cells, which stimulates division of these cells. It displays a wide range of malignant behaviour. Specific treatment is available with *tyrosine kinase inhibitors.... gastrointestinal stromal tumour
see renal cell carcinoma. [P. A. Grawitz (1850–1932), German pathologist]... grawitz tumour
an androgen-producing tumour of the ovary found in older women and often resulting in *virilization. Such tumours are so called as they tend to occur around the area of the ovary where the blood vessels enter (the hilum). They are usually small and are treated by surgical removal, with resolution of most of the symptoms.... hilar cell tumour
a malignant tumour of the thyroid gland that arises from Hürthle (or Askanazy) cells, altered follicular cells of the gland that have large nuclei and stain deeply with eosin (these cells are also found in benign nodules and Hashimoto’s disease). Hürthle cell carcinoma is not as common as papillary, follicular, or anaplastic thyroid carcinomas (see thyroid cancer). [K. W. Hürthle (1860–1945), German histologist]... hürthle cell tumour
any tumour arising in a cell of the pancreatic *islets of Langerhans. These tumours, which include *insulinomas, *glucagonomas, and *somatostatinomas, form one of the two major subclasses of gastrointestinal neuroendocrine tumours, the other being the *carcinoid tumours.... islet cell tumour
see cholangiocarcinoma. [G. Klatskin (20th century), US physician]... klatskin tumour
a rapidly developing malignant growth in one or (more often) both ovaries. It is caused by the *transcoelomic spread of a primary growth in the stomach or intestine, typically an adenocarcinoma. [F. E. Krukenberg]... krukenberg tumour
a tumour of the *interstitial (Leydig) cells of the testis. Such tumours often secrete testosterone, which in prepubertal boys causes *virilization and precocious puberty.... leydig tumour
see haemangioblastoma. [A. Lindau (1892–1958), Swedish pathologist]... lindau’s tumour
(NGF) a protein (see growth factor), consisting of two polypeptide chains, that is required for the development and longevity of some neurons, including those in the sympathetic nervous system and some central nervous system and sensory neurons. Nerve growth factor is necessary for axon growth and also for initiating new neuronal connections with other cells. The role of NGFs in preventing the degeneration of brain cells is being explored in research into Alzheimer’s disease.... nerve growth factor
any one of a group of neoplasm tumour-like malformations arising from odontogenic tissues or their remnants. The most important example is the *ameloblastoma.... odontogenic tumour
1. an accumulation of fluid (pleural effusion) in the lung in patients with heart failure, which resembles a lung tumour on radiological examination. 2. a swelling in the abdomen or elsewhere, caused by local muscular contraction or the accumulation of gases, that mimics a swelling caused by a tumour.... phantom tumour
(PDGF) see growth factor.... platelet-derived growth factor
an *adenoma of the umbilicus.... raspberry tumour
a small painless nonmalignant swelling in the lower half of the *sternomastoid muscle, appearing a few days after birth. It occurs when the neck of the fetus is in an abnormal position in the uterus, which interferes with the blood supply to the affected muscle, and it is most common after breech births. The tumour may cause a slight tilt of the head towards the tumour and turning of the face to the other side. This can be corrected by physiotherapy aimed at increasing all movements of the body, but without stretching the neck.... sternomastoid tumour
(TGF) a protein – a *cytokine – that controls growth, proliferation, and other functions in most cells. It plays a role in asthma and other respiratory diseases and is also involved in diseases elsewhere in the body. There are two classes: TGF-? and TGF-?.... transforming growth factor
a protein produced by cancer cells. Its presence in the blood can be revealed by means of a simple blood test, aiding the diagnosis of malignant melanoma and other cancers at their earliest – and most treatable – stages of development.... tumour-associated antigen
(TIL) a lymphoid cell that can infiltrate solid tumours. Such cells can be cultured in vitro, in the presence of *interleukin 2, and have been used as vehicles for *tumour necrosis factor in gene therapy trials for cancer.... tumour-infiltrating lymphocyte
a substance produced by a tumour that can be used to aid detection of the tumour and to monitor its size and the effects of treatment. An example is *alpha-fetoprotein, which is used to monitor treatment of malignant *teratomas. See also CA125; CA19-9; carcino-embryonic antigen; human chorionic gonadotrophin.... tumour marker
(VEGF) a *growth factor made by both normal cells and their abnormal or malignant counterparts to stimulate new blood vessel formation (see angiogenesis). It can be targeted by a family of drugs known as *angiogenesis inhibitors, which include *bevacizumab.... vascular endothelial growth factor
(adenolymphoma) a tumour of the parotid salivary glands, containing epithelial and lymphoid tissues with cystic spaces. [A. S. Warthin (1866–1931), US pathologist]... warthin’s tumour
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