Interstitial-cell-stimulating hormone Health Dictionary

A chemical produced in the body by endocrine glands and carried in the blood to other organs where the hormone causes processes to change in the target organ. A chemical messenger.... hormone

A generally slow growing malignant epithelial tumour, which has potential to invade and metastasise, especially if untreated.... basal cell carcinoma

The smallest unit of living material that can function independently.... cell

A hormone produced by the anterior PITUITARY GLAND which stimulates the formation of follicles in the ovary each menstrual cycle (see OVARIES; MENSTRUATION) and of spermatocytes in the testis (see TESTICLE). It is under hypothalamic control (see HYPOTHALAMUS) and in the female there is feedback inhibition by oestrogens from the developing follicle.... follicle-stimulating hormone

Those embryonic cells with the potential to develop into ova (see OVUM) or spermatozoa (see SPERMATOZOON).... germ cell

A product of the anterior part of the PITUITARY GLAND that promotes normal growth and development in the body by changing the chemical activity in the cells. The hormone activates protein production in the muscle cells as well as the release of energy from the metabolism of fats. Its release is controlled by the contrasting actions of growth-hormone releasing factor and somatostatin. If the body produces too much growth hormone before puberty GIGANTISM results; in adulthood the result is ACROMEGALY. Lack of growth hormone in children retards growth.

For many years growth hormone was extracted from human corpses and very rarely this caused CREUTZFELDT-JAKOB DISEASE (CJD) in the recipients. The hormone is now genetically engineered, so safe.... growth hormone

(LH) This is a sugar-bearing protein manufactured by the anterior pituitary. Like a lot of the pituitary hormones, it surges on and off, since constant secretion would overload and deaden receptors. In women, it builds up after menses, stimulating the release of estrogen from the ovaries. Estrogen in turn stimulates the hypothalamus to increase its stimulation of LH from the pituitary, until, a day or two before ovulation, they produce a guitar-amp feedback, and the cells that produce LH start to surge follicle-stimulating hormone (FSH). The egg pops, being replaced by the corpus luteum, which produces progesterone for the next eleven to twelve days. Progesterone inhibits and lowers LH levels, as well as inhibiting levels of estrogen already being produced by the young follicles that will produce next month’s egg. In men, LH is responsible for stimulation of testosterone, although FSH and the testes hormone inhibin are responsible for both the production of sperm and controlling testosterone.... luteinizing hormone

See HYPERNEPHROMA.... renal cell carcinoma

Malignant tumour of squamous epithelium of skin, which generally spreads and metastasises.... squamous cell carcinoma

Stem CELLS develop a few days after an egg (ovum) is fertilised by a spermatozoon and starts developing to form an EMBRYO. These master cells are crucial to the development of a normal embryo. They contain a specialised ENZYME that gives them the facility to divide inde?nitely, developing into the many di?erent specialised cells that comprise the various tissues in the body – for example, skin, blood, muscle, glands or nerves.

In a highly signi?cant advance in research, a scienti?c team in the United States obtained stem cells from newly formed human embryos

– donated by women who had become pregnant after successful in vitro fertilisation – and successfully cultivated these cells in the laboratory. This achievement opened the way to replicating in the laboratory, the various specialised cells that develop naturally in the body. UK government legislation constrains the use of human embryos in research (see ETHICS) and the ethical aspects of taking this stem-cell culture technique forwards will have to be resolved. Nevertheless, this discovery points the biological way to the use of genetic engineering in selecting di?erentiated specialised cells from which replacement tissues could be grown for use as transplants to rectify absent or damaged tissues in the human body.

Research into potential use of stem cells has raised expectations that in the long term they may prove to be an e?ective regenerative treatment for a wide range of disorders including PARKINSONISM, ALZHEIMER’S DISEASE, type-2 diabetes (see under DIABETES MELLITUS), myocardial infarction (see HEART, DISEASES OF), severe burns, osteoporosis (see under BONE, DISORDERS OF) and the regeneration of blood to replace the need for BONE MARROW TRANSPLANT. Recent research has shown that adult stem cells may also be stimulated to produce new cell lines. If successful, this would eliminate the need to use embryos and thus resolve existing ethical dilemmas over the use of stem cells.... stem cell

See: ARTERITIS. ... giant cell arteritis

Within a few years medical scientists have introduced into the domestic scene a steroid which has changed the whole course of female history. HRT has solved some basic medical problems by making good the loss of oestrogen in a woman’s body when menstruation is finished and her body learns to adjust.

A lack of oestrogen induces hot flushes, night sweats, thinning of the bones (osteoporosis) with possible fractures, and a wide range of physical and emotional disorders.

HRT also prevents the increased frequency of coronary disease which may follow the menopause. With oestrogen only, HRT appears to increase the incidence of cancer of the uterine body. Use of oestrogen and progestogen avoids this.

HRT is available as a tablet, transdermal patch, implant or topical cream. Most women notice temporary improvement in their appearance and hot flushes as long as treatment is continued. HRT is not prescribed by the herbal practitioner. Soya and Hops are a mild alternative.

Side-effects of such treatment include blood pressure rise, weight gain and periods probably continue with a monthly bleed. Elderly women taking HRT for osteoporosis may develop bleeding problems, the risk of blood clot and gall bladder diseases.

Helonias has proved a useful alternative, effective in eliminating excess fluids, reducing hot flushes, and relieving that bloated feeling, thus helping the older woman to live a normal life.

Damiana. 1 heaped teaspoon leaves to each cup boiling water; infuse 5-10 minutes; strain. 1 cup 2-3 times daily for 3-6 weeks.

Sarsaparilla. 1oz (30g) root in 1 pint (500ml) water; simmer gently 20 minutes; strain. 1 cup 2-3 times daily for 3-6 weeks.

Supplementation. Daily. Vitamin E, 400iu. Vitamin B-complex (high potency). Evening Primrose oil capsules, 500mg morning and evening. Dolomite, for Calcium and Magnesium, 2 tablets morning and evening.

Note: An extensive study of breast cancer risks with HRT revealed a positive link between the risk of cancer and length of use. Risk of the disease increased with all types of women using HRT with every year of use. Pre-menstrual women were more than twice at risk. It would appear that oestrogens cannot be taken without risk. (Centre for Disease Control, Atlanta, USA) See: OESTROGENS. ... hormone replacement therapy (hrt)

A columnar secretory cell occurring in the EPITHELIUM of the respiratory and intestinal tracts.

The cells produce the main constituents of MUCUS.... goblet cell

This is the basic cell from which all types of blood cells originate. Its appearance is believed to be similar to that of a LYMPHOCYTE.... haemopoietic stem cell

Interstitial is a term applied to indi?erent tissue set among the proper active tissue of an organ. It is generally of a supporting character and formed of ?brous tissue. The term is also applied to the ?uid always present in this in a small amount, and to diseases which specially affect this tissue, such as interstitial keratitis.... interstitial

Also called Leydig cells, these cells are scattered between the SEMINIFEROUS TUBULES of the testis (see TESTICLE). LUTEINISING HORMONE from the anterior PITUITARY GLAND stimulates the interstitial cells to produce androgens, or male hormones.... interstitial cells

These are ‘chemical messengers’ that are dispersed by the blood and act on target organs to produce effects distant from their point of release. The main organs involved in hormone production are the PITUITARY GLAND, PANCREAS, ovary (see OVARIES), testis (see TESTICLE), THYROID GLAND, and ADRENAL GLANDS. The release of many hormones is, ultimately, under the control of the central nervous system via a series of inhibiting and releasing factors from the HYPOTHALAMUS. Hormones are involved in maintaining homeostasis: for example, insulin regulates the concentration of glucose in the blood. They also participate in growth and maturation: for example, growth hormone promotes growth and helps to regulate fat, carbohydrate, and protein metabolism; and the sex hormones promote sexual maturation and reproduction. (See also ENDOCRINE GLANDS.)... hormones

(LH-RH) The same substance as Follicle-Stimulating-Hormone Releasing Hormone (FSH-RH), both of which are actually Gonadotrophin-Releasing Hormone (GnRH or GRH). Confused? Imagine being an endocrinologist 20 years ago. These (This) are (is) a peptide secreted into the little portal system that drains from the hypothalamus to the pituitary. If it is surged hourly and not too strongly, the pituitary secretes LH and the ovaries secrete estrogen. If it is surged hourly and strongly, the estrogens rise drastically, the pituitary secretes FSH, you pop an egg, start the corpus luteum and begin progesterone secretion. The surge is now slowed to every four or five hours, not too strongly, and the pituitary secretes LH every four or five hours...and the ovaries make progesterone. The same hypothalamic hormone triggers different pituitary responses based on AMPLITUDE and FREQUENCY.... luteinizing-hormone releasing hormone

See NEURON(E).... nerve cell

A type of cell found in one highly malignant form of lung cancer. The cell is small and either oval or round. The nucleus stains darkly and the cytoplasm is sparse and di?cult to identify. Oat-cell, or small-cell, carcinoma of the bronchus is usually caused by smoking, and comprises around 30 per cent of all bronchial cancers. It responds to radiotherapy and chemotherapy but, because the growth has usually spread widely by the time it is diagnosed, the prognosis is poor. Results of surgery are unsatisfactory.... oat cell

That fraction of the blood’s total volume made up of red cells. The packed cell volume is found by centrifuging blood in a tube and measuring the depth of the column of red cells as a fraction of the whole column of blood. (See also HAEMATOCRIT.)... packed cell volume

See ERYTHROCYTES; BLOOD.... red blood cell

These HORMONES control the development of primary and secondary sexual characteristics. They also regulate sex-related functions – for example, menstruation and the production of sperm and eggs. The three main types of sex hormone are androgens, or male sex hormones (see ANDROGEN); OESTROGENS, or female sex hormones; and progesterones, which are involved in pregnancy (see PROGESTERONE).... sex hormones

See OAT CELL.... small-cell carcinoma

A specialised white cell (lymphocyte) responsible for cell-mediated immunity. See also T-lymphocyte.... t-cell

Abnormal ERYTHROCYTES which are large and ‘?oppy’ and have a ringed appearance, similar to that of a target, when stained and viewed under the microscope. This change from normal may occur with iron-de?ciency ANAEMIA, liver disease, a small SPLEEN, haemoglobinopathies (disorders of HAEMOGLOBIN), and THALASSAEMIA.

A target cell is also a cell that is the focus of attack by macrophages (killer cells – see MACROPHAGE) or ANTIBODIES; it may also be the site of action of a speci?c hormone (see HORMONES).... target cell

See LEUCOCYTES.... white blood cell

See ACTH.... adrenocorticotrophic hormone

See ADH.... antidiuretic hormone

See lymphocyte.... b-cell

The processes by which cells multiply. Mitosis is the most common form of cell division, giving rise todaughter cells identical to the parent cells.

Meiosis produces egg (see ovum) and sperm cells that differ from their parent cells in that they have only half the normal number of chromosomes.... cell division

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

A type of cell that plays an important part in allergy.

In an allergic response, mast cells release histamine.... mast cell

ACTH is the commonly used abbreviation for CORTICOTROPIN.... acth (adrenocorticotrophic hormone)

See also CORTICOTROPIN. A hormone which is released into the body during stress. Made and stored in the anterior PITUITARY GLAND, ACTH regulates the production of corticosteroid hormones from the ADRENAL GLANDS, and is vital for the growth and maintenance of the adrenal cortical cells. Its production is in part controlled by the amount of HYDROCORTISONE in the blood and also by the HYPOTHALAMUS. ACTH participates in the FEEDBACK MECHANISM of hormone production and actions involving particularly the hypothalamus and pituitary gland. The hormone is used to test adrenal function and treat conditions such as ASTHMA. (See also CUSHING’S SYNDROME.)... adrenocorticotrophic hormone (acth)

See VASOPRESSIN.... antidiuretic hormone (adh)

A type of white blood cell that circulates through the body and is able to detect the presence of the foreign agents. Once exposed to an antigen on the agent, these cells differentiate into plasma cells to produce antibody.... b-lymphocyte (or b-cell)

See TRANSFUSION.... cell salvage transfusion

A defence mechanism involving the coordinated activity of two subpopulations of TLymphocytes, helper T-Cells and killer T-Cells. Helper T-Cells produce a variety of substances that stimulate and regulate other participants in the immune response. Killer T-Lymphocytes destroy cells in the body that bear foreign antigens (e.g. cells that are infected with viruses or other microorganisms).... cell-mediated immunity

See OESTRADIOL.... follicular hormone

See under MENOPAUSE.... hormone replacement therapy(hrt)

The hydrogel that surrounds cells in soft tissues. It is a mucopolysaccaride starch gel, and the serum that leaves the blood capillaries flows through this gel, some to return to the exiting venous blood, some to enter the lymph system. There is an old medical axiom: the blood feeds the lymph, and the lymph feeds the cells. Interstitial fluid that flows through the starch colloid is this lymph.... interstitial fluid

A hormone secreted by the anterior PITUITARY GLAND which stimulates OVULATION, maturation of the CORPUS LUTEUM, and the synthesis of progesterone by the ovary (see OVARIES) and testosterone by the testis (see TESTICLE).... luteinising hormone

A natural hormone released by the HYPOTHALAMUS gland in the BRAIN. It stimulates the release of GONADOTROPHINS from the PITUITARY GLAND; these control the production of the sex hormones (see ANDROGEN; OESTROGENS).... luteinising hormone-releasing hormone (lhrh)

A method of autologous blood TRANSFUSION – using a patient’s own blood, salvaged during a surgical operation – instead of conventional blood-bank transfusion.... perioperative cell salvage

These have almost completely replaced BONE MARROW TRANSPLANT, used to treat malignancies such as LEUKAEMIA and LYMPHOMA for the past 20 years. The high doses of CHEMOTHERAPY or RADIOTHERAPY used to treat these diseases destroy the bone marrow which contains stem cells from which all the blood cells derive. In 1989 stem cells were found in the blood during recovery from chemotherapy. By giving growth factors (cytokines), the number of stem cells in the blood increased for about three to four days. In a peripheral-blood stem-cell transplant, these cells can be separated from the peripheral blood, without a general anaesthetic. The cells taken by either method are then frozen and returned intravenously after the chemotherapy or radiotherapy is completed. Once transplanted, the stem cells usually take less than three weeks to repopulate the blood, compared to a month or more for a bone marrow transplant. This means that there is less risk of infection or bleeding during the recovery from the transplant. The whole procedure has a mortality risk of less than 5 per cent – half the risk of a bone marrow transplant.... peripheral-blood stem-cell transplants

The cells that produce the MYELIN sheath of the AXON of a medullated NERVE. They are wrapped around a segment of the axon, forming concentric layers.... schwann cell

These are fats similar to, and usually synthesized from, cholesterol, starting with Acetyl-CoA, moving through squalene, past lanosterol, into cholesterol, and, in the gonads and adrenal cortex, back to a number of steroid hormones. Nearly all of the classic hormones are proteins or smaller peptides; they don’t get inside a cell (the membrane keeps them out); instead, they bind to, and initiate, cell changes from the outside. The exceptions are the thyroxines (from the thyroid) and the steroid hormones. They move into the cell, bind with receptors, and initiate changes in the way a cell regenerates itself or synthesizes new compounds. Because the steroid hormones stimulate cell growth, either by changing the internal structure or increasing the rate of proliferation, they are often called anabolic steroids. Estrogen, an ovarian steroid, when secreted into the bloodstream, will be bound within a short time by internal receptors inside those cells that need estrogen for their growth; the unused portion is partially broken down, mostly in the liver, and partially stored in a less active form by adipose tissue. Since luteinizing hormone from the pituitary is surged in pulses an hour apart, the estrogen is also surged from the reacting ovaries, and by the time more estrogen is available, the binding cells need more; their program of synthesis has run out and needs to be started again. Of course, most steroid hormone reactions are less measured than this, but you get the idea.... steroid hormone

See LYMPHOMA.... t-cell lymphoma

A hormone (see HORMONES) produced and released by the HYPOTHALAMUS which stimulates the release of THYROTROPHINSTIMULATING HORMONE (TSH) by the PITUITARY GLAND.... thyrotrophin-releasing hormone (trh)

A hormone (see HORMONES) manufactured and released by the anterior part of the PITUITARY GLAND which stimulates the THYROID GLAND to manufacture and release thyroid hormones (THYROXINE and TRI-IODOTHYRONINE).... thyrotrophin-stimulating hormone (tsh)

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

A group of hormones produced by the adrenal glands that control the body’s use of nutrients and the excretion of salts and water in the urine.... corticosteroid hormones

A form of anaemia growing into an acute social problem, affecting people of African, Asian, and Mediterranean origin. Thalassaemias are caused by defects of a gene that produces the globin part of haemoglobin. Such defects in the DNA can now be detected in the womb before birth. The name derives from sickle-shaped cells instead of circular red blood cells. Few sufferers survive beyond their 40th year.

Symptoms. Unhealthy pallor, listlessness, sore tongue, dizziness, vague aches and pains, rapid pulse and breathing, tinnitus, palpitation. The skull may be disproportionately large, resistance to infection feeble, chances of survival poor. This form of anaemia is linked with defective colour vision. Impaired liver function. Stunted growth, great pain. Sufferers have a higher risk of infection.

Malaria. Sufferers are less likely to die of malaria because their red cells do not support the growth of malaria parasites very well.

Carriers: Carriers of the sickle-cell gene can now be identified by a simple blood test.

Treatment. No specifics exist but supportive herbal treatment has been known to increase output of red cells and raise haemoglobin levels:– Red Clover flowers, Yellow Dock, Echinacea, Burdock, Wild Indigo, Gentian, Nettles, Birch leaves, Sage, Walnut leaves, Centaury, Gota Kola (Indian Pennywort). Alternatives:– Tea. Mix equal parts: Iceland Moss, Nettles, Red Clover flowers. 2 teaspoons to each cup boiling water; infuse 15 minutes; 1 cup morning and evening.

Decoction. Mix equal parts; Echinacea, Walnut leaves, Balm of Gilead buds; 1 teaspoon to each cup water gently simmered for 20 minutes. Half-1 cup, cold, 3 times daily, before meals.

Tablets/capsules. Sarsaparilla. Ginseng. Iceland Moss. Red Clover. Echinacea. Gentian.

Powders. Formula: Echinacea 1; Fringe Tree half; Ginseng half; White Poplar bark 1. Dose: 500mg (two 00 capsules or one-third teaspoon) thrice daily before meals.

Liquid extracts. Formula. Echinacea 2; Dandelion 1; Oat Husk (avena sativa) 1. Mix. Dose, 1-2 teaspoons before meals, in water or one of the above teas or decoctions.

Tinctures. Same combination. Dose: 2-3 teaspoons.

Dong quai. See entry.

Pollen. Claimed to be of value.

Diet. Dandelion coffee. Molasses. Desiccated liver. Calf liver, fresh. Green leafy vegetables contain chlorophyll, iron and folic acid. Cider vinegar. Dried beans, apricots and shellfish. Dandelion leaves in salads. Milk, eggs, meats, Soya. Carrot juice to increase red cells.

Supplements. Daily. Vitamin B12. Vitamin C, 1g; Folic acid 400mcg, Floradix. Of particular value: Vitamin E 400iu. Zinc.

Note: Those at risk should submit themselves for screening. The disease cannot be cured but can be controlled largely by orthodox measures and sometimes by natural medicine. ... anaemia: sickle cell

Given three months to live, Jason Winters, terminal cancer patient, was suffering from infiltrating squamous cell carcinoma wrapped round his carotid artery. Refusing major surgery, he travelled the world in search of native remedies. He was able to contact people who put him on the track of Wild Violet leaves, Red Clover flowers (Trifolium pratense) and leaves of the Chaparral bush (Larrea divaricata). The story of how he infused them, together with a well- known spice, is dramatically recorded in his book “Killing Cancer”. After a spectacular recovery, remission has lasted for over 15 years and others have benefited from his experience.

Treatment by oncologist. ... cancer – squamous cell carcinoma

A group of hormones released from specialized cells in the stomach, pancreas, and intestine that control various functions of the digestive organs. Gastrin, secretin, and cholecystokinin are the best known of these hormones.... gastrointestinal hormones

Hormones that stimulate cell activity in the ovaries and testes. Gonadotrophins are essential for fertility. The two most important gonadotrophins are follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which are secreted by the pituitary gland. Another gonadotrophin, HCG (see gonadotrophin, human chorionic), is produced by the placenta during pregnancy. Certain gonadotrophins are used as drugs in the treatment of infertility.... gonadotrophin hormones

A drug that blocks the action of a hormone.... hormone antagonist

Scarring of lung tissue mainly involving the alveoli. There are a number of causes, including occupational exposure to dusts and fibrosing alveolitis, which is an autoimmune disorder.... interstitial pulmonary fibrosis

Treatment of a cancerous tumour by inserting radioactive material into the growth or into neighbouring tissue. Using this method, also called brachytherapy, radiation can be targeted at the diseased area.

Radioactive material (usually artificial radioisotopes) contained in wires, small tubes, or seeds is then implanted into or near the diseased tissue under general anaesthesia. The material is left in place for variable amounts of time depending on the radioactive substance and the tumour being treated. (See also intracavitary therapy; radiotherapy.)... interstitial radiotherapy

A group of hormones that are essential for normal female sexual development and healthy functioning of the reproductive system.

In women, they are produced mainly in the ovaries and also in the placenta in pregnancy.

Small amounts are produced in the adrenal glands in both men and women, but oestrogens have no known specific function in men.

When levels are low, oestrogen hormones can be replaced with oestrogen drugs.... oestrogen hormones

A female sex hormone essential for the functioning of the female reproductive system.

Progesterone is made in the ovaries, and small amounts are produced by the adrenal glands and testes.

During the menstrual cycle, changing progesterone levels cause thickening of the endometrium and menstruation.

If pregnancy occurs, progesterone is produced by the placenta; a fall in its level helps to initiate labour.

Progesterone also causes increased fat deposition and increased sebum production by glands in the skin.... progesterone hormone

An inherited blood disease in which the red blood cells contain haemoglobin S, an abnormal type of haemoglobin. This crystallizes in the capillaries, making red cells sickle-shaped and fragile, and leading to haemolytic anaemia. The abnormal cells are unable to pass easily through tiny blood vessels. The blood supply to organs is blocked intermittently, causing sickle cell crises. The disease affects mainly black people.Symptoms usually appear after age 6 months, often beginning with painful swelling of the hands and feet. Chronic haemolytic anaemia causes fatigue, headaches, shortness of breath on exertion, pallor, and jaundice. Sickle cell crises start suddenly; they are sometimes brought on by an infection, cold weather, or dehydration, but may also occur for no apparent reason. The sufferer may experience pains (especially in the bones), blood in the urine (from kidney damage) or damage to the lungs or intestines. If the brain is affected, seizures, a stroke, or unconsciousness may result.

In some affected children, the spleen enlarges and traps red cells at a particularly high rate, causing a life-threatening form of anaemia. After adolescence, the spleen usually stops functioning, increasing the risk of infection in those affected.

Diagnosis is made from examination of a blood smear and electrophoresis.

Supportive treatment may include folic acid supplements, and penicillin and immunization to protect against infection.

Life-threatening crises are treated with intravenous infusions of fluids, antibiotics, oxygen therapy, and analgesic drugs.

If the crisis still does not respond, an exchange blood transfusion may be performed.

This may be done regularly for people who suffer frequent severe crises.... sickle cell anaemia

(APC) a cell, such as a *dendritic cell or a *macrophage, that processes antigen for presentation to a T lymphocytes (see helper T cell).... antigen-presenting cell

see Müllerian duct.... anti-müllerian hormone

(blood corpuscle) any of the cells that are present in the blood in health or disease. The cells may be subclassified into three major categories, namely red cells (*erythrocytes); white cells (*leucocytes), which include granulocytes, lymphocytes, and monocytes; and *platelets (see illustration). The blood cells account for approximately 40% of the total volume of the blood in health; red cells comprise the vast majority.... blood cell

(echinocyte) a red blood cell (erythrocyte) with abnormal small thorny projections. See crenation.... burr cell

(perikaryon) the enlarged portion of a *neuron (nerve cell), containing the nucleus. It is concerned more with the nutrition of the cell than with propagation of nerve impulses.... cell body

a machine that aspirates blood lost during surgery and immediately spins, washes, and filters it for retransfusion back into the patient’s body (see autotransfusion). The process, called intraoperative cell salvage, is used in surgery that has significant blood loss, such as orthopaedic and vascular surgery and Caesarean section, and avoids the costs and risks of *allogeneic transfusion.... cell saver

molecules on the surface of cell membranes that are responsible for most cellular functions directly related to their immediate environment. Many have very precise functions of adhesion (see adhesion molecules), metabolic exchange, hormone reception, respiration, and immune reactions. Cell-to-cell exchanges involve specialized surface structures (junctions), which form a communicating nexus.... cell-surface molecules

(clear-cell adenocarcinoma) a variant of *adenocarcinoma that tends to arise from the kidneys or the female genital tract. In the latter case it is linked to intrauterine exposure to *diethylstilbestrol during the 1950s and 1960s and takes the form of a vaginal cancer, which can be treated by radical surgery followed by radiotherapy.... clear-cell carcinoma

(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

(CRH) a peptide hypothalamic hormone (of 41 amino acids) stimulating the release of *ACTH (adrenocorticotrophic hormone) from the anterior pituitary. Its own release is suppressed by a *negative feedback loop involving cortisol, and its action is increased by antidiuretic hormone (see vasopressin) and *angiotensin II. It can be administered intravenously as part of the CRH test, during which blood is analysed at 15-minute intervals for one hour for the ACTH response, which is excessive in cases of primary adrenal failure and suppressed in cases of anterior *hypopituitarism.... corticotrophin-releasing hormone

a group of lymphomas in which abnormal T *lymphocytes are concentrated in the skin. The most common form is *mycosis fungoides.... cutaneous t-cell lymphoma

a type of T *lymphocyte that destroys cancerous cells, virus-infected cells, and *allografts. Cytotoxic T cells recognize peptide antigens attached to proteins that are encoded by the *HLA system.... cytotoxic t cell

a type of haemopoietic cell with specialized antigen-presenting functions. The head and neck are common sites for dendritic cell pathology. See antigen-presenting cell.... dendritic cell

a hormone produced by cells that do not usually produce it. Some tumour cells secrete hormones; for example, small-cell lung cancer cells secrete antidiuretic hormone and cause *hyponatraemia.... ectopic hormone

see ovum.... egg cell

n. any of the gastrin-secreting cells of the stomach lining located predominantly in the gastric *antrum. Gastrin stimulates the production of gastric acid by parietal cells in the stomach. Increased G-cell activity is associated with the formation of duodenal ulcers and the *Zollinger-Ellison syndrome.... g-cell

any large cell, such as a *megakaryocyte. Giant cells may have one or many nuclei.... giant cell

(GnRH, gonadorelin) a peptide hormone produced in the hypothalamus and transported via the bloodstream to the pituitary gland, where it controls the synthesis and release of pituitary *gonadotrophins. It may be used to test the ability of the pituitary to produce gonadotrophins. *Gonadorelin analogues are used to treat endometriosis, fibroids, some types of infertility, and prostate cancer.... gonadotrophin-releasing hormone

an abnormal white blood cell that has the appearance of an immature lymphocyte with fine hairlike cytoplasmic projections around the perimeter of the cell. It is found in a rare form of leukaemia (hairy-cell leukaemia) most commonly occurring in young men.... hairy cell

a type of T *lymphocyte that plays a key role in cell-mediated immunity by recognizing foreign antigen on the surface of *antigen-presenting cells when this is associated with the individual’s *MHC antigens, having been processed by antigen-presenting cells. Helper T cells stimulate the production of *cytotoxic T cells, which destroy the target cells.... helper t cell

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 family of plasma proteins whose function is to bind free hormone molecules to varying degrees and thus reduce their function. Alterations in levels of the binding globulins, for example during pregnancy or ill health, can result in variations in assays of hormone levels in individuals. Examples include thyroid-binding globulin, sex-hormone-binding globulin, and corticosteroid-binding globulin.... hormone-binding globulins

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

a chronic nonbacterial inflammation of the bladder accompanied by an urgent desire to pass urine frequently and bladder pain; it is sometimes associated with an ulcer in the bladder wall (Hunner’s ulcer). The cause is unknown and *contracture of the bladder eventually occurs. Treatment is by distension of the bladder under spinal or epidural anaesthetic, instillation of anti-inflammatory solutions into the bladder, and administration of steroids or *NSAIDs. Bladder enhancement or augmentation (see cystoplasty) may be required for a contracted bladder.... interstitial cystitis

disease of the *tubulointerstitium of the kidney. Acute interstitial nephritis (AIN) represents in many cases an allergic reaction to drugs (especially ampicillin, cephalexin, NSAIDs, allopurinol, and frusemide). AIN can also be associated with acute infections and autoimmune disease. Thirst and polyuria may be prominent, and renal function severely affected. In allergic cases, the use of steroids hastens recovery after the allergen has been removed. Chronic interstitial nephritis (CIN) is associated with progressive scarring of the tubulointerstitium, often with lymphocyte infiltration. Primary causes of CIN include gout, radiation nephropathy, sarcoidosis, *analgesic nephropathy, reflux nephropathy, chronic hypokalaemia and hypercalcaemia, and *Aristolochia-associated nephropathies. Management of CIN involves removal of the precipitating cause, where identified, and control of hypertension.... interstitial nephritis

(interstitial pneumonitis) an alternative name for *idiopathic pulmonary fibrosis used by lung pathologists to classify the different cellular types of the disease. The most common cellular pattern is usual interstitial pneumonia (UIP). A differing cellular pattern is seen in patients with nonspecific interstitial pneumonia (NSIP), who have a better prognosis than those with UIP. There are two variants of NSIP: cellular and fibrosing. The former has chronic inflammatory cells with minimal collagen deposition, while the latter consists of diffuse interstitial fibrosis with fewer inflammatory cells. It is believed that corticosteroid therapy can slow the progression of cellular to fibrosing NSIP.... interstitial pneumonia

a group of autoantibodies directed against components of the insulin-secreting beta cells of the pancreas. They are usually detectable in the blood of people presenting with type 1 diabetes. Antibodies against *glutamic acid decarboxylase (GAD) in the beta cells have become a more specific test for islet cell antibodies, to help confirm a diagnosis of type 1 diabetes.... islet cell antibodies

a new technique still under evaluation for curing type 1 *diabetes mellitus, which involves the injection of donated cells from the pancreatic *islets of Langerhans into the liver, where it is hoped they will seed and survive. The transplanted cells then take over insulin production from the recipient’s diseased pancreas.... islet cell transplantation

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 prolactin.... lactogenic hormone

overgrowth of cells of the *reticuloendothelial system. This includes disorders previously called histiocytosis X, including eosinophilic granuloma, Hand–Schüller–Christian disease, and Letterer–Siwe disease. [P. Langerhans (1847–88), German physician and anatomist]... langerhans cell histiocytosis

(luteotrophin) see prolactin.... luteotrophic hormone

(MSH) a peptide hormone produced and secreted by the anterior pituitary gland. In humans it stimulates production and dispersal of melanin in the melanocytes. Alpha-melanocyte-stimulating hormone (?-MSH), which is released by neurons in the hypothalamus, suppresses appetite and regulates energy balance. It also stimulates sexual activity and is involved in regulation of heart rate and blood pressure.... melanocyte-stimulating hormone

a long-lived lymphocyte that is formed following primary infection. It enables a faster and more robust immune response following a second exposure to the antigen.... memory cell

(NK cell) a type of *lymphocyte that is able to kill virus-infected cells and cancerous cells and mediates rejection of bone-marrow grafts. NK cells are a part of natural (or innate) *immunity. Their function is regulated by a balance between activating receptors, which recognize proteins on cancerous or virus-infected cells, and inhibitory receptors specific for certain molecules encoded by the *HLA system.... natural killer cell

see natural killer cell.

nm symbol for *nanometre.... nk cell

(NSCLC) any type of lung cancer other than *small-cell lung cancer. Such cancers include *adenocarcinoma of the lung, large-cell carcinomas, and squamous-cell carcinoma of the lung.... non-small-cell lung cancer

(NSIP) see interstitial pneumonia.... nonspecific interstitial pneumonia

a posterior ethmoidal sinus air cell (see paranasal sinuses). They are surgically important because of their proximity to the optic nerve and internal carotid artery. [A. Onodi (1857–1919), Hungarian rhinolaryngologist]... onodi cell

(parathormone) a hormone, synthesized and released by the parathyroid glands, that controls the distribution of calcium and phosphate in the body. A high level of the hormone causes transfer of calcium from the bones to the blood; a deficiency lowers blood calcium levels, causing *tetany. This condition may be treated by injections of calcium gluconate. Compare calcitonin.

Recombinant parathyroid hormone (Preotact) is given by subcutaneous injection to treat postmenopausal osteoporosis.... parathyroid hormone

(PTH-RP) a protein that is secreted by certain malignant tumours and is the main cause of malignant *hypercalcaemia. PTH-RP, which has effects similar to *parathyroid hormone, stimulates generalized bone resorption and excessive calcium reabsorption in the kidney tubules. It is most commonly produced by lung tumours, squamous-cell carcinomas of other organs, melanomas, and tumours of the breast, liver, pancreas, bladder, and prostate.... parathyroid hormone-related protein

a type of neuron found in the *cerebral cortex, with a pyramid-shaped cell body, a branched dendrite extending from the apex towards the brain surface, several dendrites extending horizontally from the base, and an axon running in the white matter of the hemisphere.... pyramidal cell

a large binucleate cell that is characteristic of *Hodgkin’s disease. [D. Reed Mendenhall (1874–1964), US pathologist; C. Sternberg (1872–1935), Austrian pathologist]... reed–sternberg cell

(Treg cell) a type of T *lymphocyte that suppresses immune responses.... regulatory t cell

a cell that is not undergoing division. See interphase.... resting cell

any steroid hormone, produced mainly by the ovaries or testes, that is responsible for controlling sexual development and reproductive function. *Oestrogens and *progesterone are the female sex hormones; *androgens are the male sex hormones.... sex hormone

(drepanocytosis) a hereditary blood disease that mainly affects people of African ancestry but also occurs in the Mediterranean region and reaches high frequencies in parts of Saudi Arabia and India. It occurs when the sickle-cell gene has been inherited from both parents and is characterized by the production of an abnormal type of *haemoglobin – sickle-cell haemoglobin (Hbs) – which precipitates in the red cells when the blood is deprived of oxygen, forming crystals that distort the cells into the characteristic sickle shape: this process is known as sickling. An excess of sickle cells in the circulation results in blockage of small blood vessels, producing episodes of severe pain (a sickle-cell crisis). Sickle cells are rapidly removed from the circulation, leading to anaemia and jaundice. There is no satisfactory treatment; the highest mortality is in childhood but some patients may live to an age of 60–70 years.

The carrier condition (sickle-cell trait) occurs when the defective gene is inherited from only one parent. It generally causes no symptoms but confers some protection from malaria, which accounts for the high frequency of the gene in malarious areas. If a general anaesthetic is to be given to a patient with this condition, the anaesthetist should be alerted.... sickle-cell disease

progressive renal disease developing in 5–8% of patients with *sickle-cell disease. Infarcts in the cortex can occur with sickle-cell crises and present with pain and haematuria. Acute or more insidious damage to the medulla will lead to a urinary concentrating defect and later to papillary necrosis and/or fibrosis. Occlusion of vessels within the glomerular capillary tuft leads to a secondary form of *focal segmental glomerulosclerosis and can present with the *nephrotic syndrome.... sickle-cell nephropathy

(SCLC) a type of bronchial carcinoma characterized by small cells (or oat cells), small round or oval cells with darkly staining nuclei and scanty indistinct cytoplasm. Small-cell carcinoma is usually related to smoking and accounts for about one-quarter of bronchial carcinomas; it carries a poor prognosis due to early distant spread, typically to bones, liver, and brain. Treatment is primarily with chemotherapy and radiotherapy and paraneoplastic symptoms (see paraneoplastic syndrome) from *ectopic hormone production are common. Compare non-small-cell lung cancer.... small-cell lung cancer

see Reed–Sternberg cell.... sternberg–reed cell

a type of T *lymphocyte that prevents an immune response by B cells or other T cells to an antigen.... suppressor t cell

an iodine-containing substance, synthesized and secreted by the thyroid gland, that is essential for normal metabolic processes and mental and physical development. There are two thyroid hormones, *triiodothyronine and *thyroxine, which are formed from *thyroglobulin. Lack of these hormones gives rise to *cretinism in infants and *myxoedema in adults. Excessive production of thyroid hormones gives rise to *thyrotoxicosis.... thyroid hormone

(SIADH) a condition of inappropriately high plasma levels of ADH (see vasopressin) with associated water retention, dilutional *hyponatraemia, and the production of highly concentrated urine. Renal, adrenal, thyroid, and hepatic function are normal, as is the volume of circulating blood (euvolaemia). It is caused by a variety of pathological conditions, usually intrathoracic and intracerebral, and also by a number of drugs, including antidepressants, chemotherapy agents, and some of the older antidiabetic agents. The treatment involves fluid restriction, treatment (or removal) of the underlying cause (or drug), and, in severe cases, administration of *demeclocycline to reduce the effects of ADH on the kidney. Very rarely, hypertonic saline is given.... syndrome of inappropriate secretion of antidiuretic hormone

(TSH, thyrotrophin) a hormone, synthesized and secreted by the anterior pituitary gland under the control of *thyrotrophin-releasing hormone, that stimulates activity of the thyroid gland. Raised levels of TSH are found in primary *hypothyroidism. Normal or low TSH levels in the presence of a low serum thyroxine are found in secondary hypothyroidism and the *euthyroid sick syndrome.... thyroid-stimulating hormone

(TRH) a hormone from the hypothalamus (in the brain) that acts on the anterior pituitary gland to stimulate the release of *thyroid-stimulating hormone. A preparation of TRH (protirelin) may be given by intravenous injection to test thyroid gland function and to estimate reserves of thyroid-stimulating hormone in the pituitary.... thyrotrophin-releasing hormone

a form of cancer that affects the urothelium, which lines the urinary collecting system of the kidney, ureters, bladder, and the proximal part of the urethra. It is the most common type of bladder cancer.... transitional cell carcinoma

see regulatory T cell.... treg cell

(UIP) see interstitial pneumonia; idiopathic pulmonary fibrosis.... usual interstitial pneumonia