immunoglobulin bands found in the cerebrospinal fluid (CSF) taken at *lumbar puncture. Bands isolated only in the CSF and not in the serum indicate local synthesis and are seen in such conditions as multiple sclerosis.
Nutritional Profile Energy value (calories per serving): Moderate Protein: Low Fat: High Saturated fat: High Cholesterol: None Carbohydrates: Moderate Fiber: High to very high Sodium: Low Major vitamin contribution: Vitamins A, folate, vitamin C Major mineral contribution: Potassium
About the Nutrients in This Food The avocado is an unusual fruit because about 16 percent of its total weight is fat, primarily monounsaturated fatty acids. Like many other fruits, avo- cados are high in fiber (the Florida avocado is very high in fiber), a good source of the B vitamin folate, vitamin C, and potassium. The edible part of half of one average size avocado (100 g/3.5 ounces) provides 6.7 g dietary fiber, 15 g fat (2.1 g saturated fat, 9.7 g monoun- saturated fat, 1.8 g polyunsaturated fat), 81 mcg folate (20 percent of the R DA), 20 mg vitamin C (26 percent of the R DA for a woman, 22 percent for a man), and 485 mg potassium (the equivalent of one eight-ounce cup of fresh orange juice). The edible part of one-half a Florida avocado (a.k.a. alligator pear) has eight grams dietary fiber, 13.5 g fat (2.65 g saturated fat), 81 mcg folate (41 percent of the R DA for a man, 45 percent of the R DA for a woman), 12 mg vitamin C (20 percent of the R DA), and 741 mg potassium, 50 percent more than one cup fresh orange juice.
Diets That May Exclude or Restrict This Food Controlled-potassium diet Low-fat diet
Buying This Food Look for: Fruit that feels heavy for its size. The avocados most commonly sold in the U.S. are the Hass—a purple-black bumpy fruit that accounts for 85 percent of the avocados shipped from California—and the smooth-skinned Florida avocado (“alligator pear”). The oval, midwinter Bacon; the pear-shaped, late-fall Fuerte; the Gwen, a slightly larger Hass; Pinkerton, pear-shaped with a smaller seed; the round summer Reed; and the yellow-green, pear-shaped Zutano. Avoid: Avocados with soft dark spots on the skin that indicate damage underneath.
Storing This Food Store hard, unripened avocados in a warm place; a bowl on top of the refrigerator will do. Avocados are shipped before they ripen, when the flesh is hard enough to resist bruising in transit, but they ripen off the tree and will soften nicely at home. Store soft, ripe avocados in the refrigerator to slow the natural enzyme action that turns their flesh brown as they mature even when the fruit has not been cut.
Preparing This Food When you peel or slice an avocado, you tear its cell walls, releasing polyphenoloxidase, an enzyme that converts phenols in the avocado to brownish compounds that darken the avocado’s naturally pale green flesh. You can slow this reaction (but not stop it completely) by brushing the exposed surface of the avocado with an acid (lemon juice or vinegar). To store a cut avocado, brush it with lemon juice or vinegar, wrap it tightly in plastic, and keep it in the refrigerator—where it will eventually turn brown. Or you can store the avocado as guacamole; mixing it with lemon juice, tomatoes, onions, and mayonnaise (all of which are acidic) is an efficient way to protect the color of the fruit.
Medical Uses and/or Benefits Lower risk of some birth defects. As many as two of every 1,000 babies born in the United States each year may have cleft palate or a neural tube (spinal cord) defect due to their moth- ers’ not having gotten adequate amounts of folate during pregnancy. The current R DA for folate is 180 mcg for a healthy woman and 200 mcg for a healthy man, but the FDA now recommends 400 mcg for a woman who is or may become pregnant. Taking folate supple- ments before becoming pregnant and through the first two months of pregnancy reduces the risk of cleft palate; taking folate through the entire pregnancy reduces the risk of neural tube defects. Lower risk of heart attack. In the spring of 1998, an analysis of data from the records for more than 80,000 women enrolled in the long-running Nurses’ Health Study at Harvard School of Public Health/Brigham and Woman’s Hospital, in Boston, demonstrated that a diet providing more than 400 mcg folate and 3 mg vitamin B6 daily, from either food or supplements, more than twice the current R DA for each, may reduce a woman’s risk of heart attack by almost 50 percent. Although men were not included in the analysis, the results are assumed to apply to them as well. However, data from a meta-analysis published in the Journal of the American Medical Association in December 2006 called this theory into question. Researchers at Tulane Univer- sity examined the results of 12 controlled studies in which 16,958 patients with preexisting cardiovascular disease were given either folic acid supplements or placebos (“look-alike” pills with no folic acid) for at least six months. The scientists, who found no reduction in the risk of further heart disease or overall death rates among those taking folic acid, concluded that further studies will be required to ascertain whether taking folic acid supplements reduces the risk of cardiovascular disease. Lower levels of cholesterol. Avocados are rich in oleic acid, a monounsaturated fat believed to reduce cholesterol levels. Potassium benefits. Because potassium is excreted in urine, potassium-rich foods are often recommended for people taking diuretics. In addition, a diet rich in potassium (from food) is associated with a lower risk of stroke. A 1998 Harvard School of Public Health analysis of data from the long-running Health Professionals Study shows 38 percent fewer strokes among men who ate nine servings of high potassium foods a day vs. those who ate less than four servings. Among men with high blood pressure, taking a daily 1,000 mg potas- sium supplement—about the amount of potassium in one avocado—reduced the incidence of stroke by 60 percent.
Adverse Effects Associated with This Food Latex-fruit syndrome. Latex is a milky fluid obtained from the rubber tree and used to make medical and surgical products such as condoms and protective latex gloves, as well as rubber bands, balloons, and toys; elastic used in clothing; pacifiers and baby-bottle nipples; chewing gum; and various adhesives. Some of the proteins in latex are allergenic, known to cause reactions ranging from mild to potentially life-threatening. Some of the pro- teins found naturally in latex also occur naturally in foods from plants such as avocados, bananas, chestnuts, kiwi fruit, tomatoes, and food and diet sodas sweetened with aspar- tame. Persons sensitive to these foods are likely to be sensitive to latex as well. NOT E : The National Institute of Health Sciences, in Japan, also lists the following foods as suspect: A lmonds, apples, apricots, bamboo shoots, bell peppers, buckwheat, cantaloupe, carrots, celer y, cherries, chestnuts, coconut, figs, grapefruit, lettuce, loquat, mangoes, mushrooms, mustard, nectarines, oranges, passion fruit, papaya, peaches, peanuts, peppermint, pine- apples, potatoes, soybeans, strawberries, walnuts, and watermelon.
Food/Drug Interactions MAO inhibitors. Monoamine oxidase (M AO) inhibitors are drugs used as antidepressants or antihypertensives. They inhibit the action of enzymes that break down the amino acid tyramine so it can be eliminated from the body. Tyramine is a pressor amine, a chemical that constricts blood vessels and raises blood pressure. If you eat a food such as avocado that contains tyramine while you are taking an M AO inhibitor you cannot eliminate the pressor amine, and the result may be abnormally high blood pressure or a hypertensive crisis (sus- tained elevated blood pressure). False-positive test for tumors. Carcinoid tumors (which may arise from tissues in the endo- crine system, the intestines, or the lungs) secrete serotonin, a natural chemical that makes blood vessels expand or contract. Because serotonin is excreted in urine, these tumors are diagnosed by measuring the levels of serotonin by-products in the urine. Avocados contain large amounts of serotonin; eating them in the three days before a test for an endocrine tumor might produce a false-positive result, suggesting that you have the tumor when in fact you don’t. (Other foods high in serotonin are bananas, eggplant, pineapples, plums, tomatoes, and walnuts.)... avocados
Nutritional Profile Energy value (calories per serving): Moderate Protein: Low Fat: Low Saturated fat: Low Cholesterol: None Carbohydrates: High Fiber: Moderate Sodium: Low Major vitamin contribution: B vitamins, vitamin C Major mineral contribution: Potassium, magnesium
About the Nutrients in This Food A banana begins life with more starch than sugar, but as the fruit ripens its starches turn to sugar, which is why ripe bananas taste so much better than unripe ones.* The color of a banana’s skin is a fair guide to its starch/ sugar ratio. When the skin is yellow-green, 40 percent of its carbohydrates are starch; when the skin is fully yellow and the banana is ripe, only 8 per- cent of the carbohydrates are still starch. The rest (91 percent) have broken down into sugars—glucose, fructose, sucrose, the most plentiful sugar in the fruit. Its high sugar content makes the banana, in its self-contained packet, a handy energy source. Bananas are a high-fiber food with insoluble cellulose and lignin in the tiny seeds and soluble pectins in the flesh. They are also a good source of vitamin C and potassium. One small (six-inch) banana or a half-cup of sliced banana has 2.6 g dietary fiber and 8.8 mg vitamin C (12 percent of the R DA for a woman, 10 percent of the R DA for a man), plus 363 mg potassium.
The Most Nutritious Way to Serve This Food Fresh and ripe. Green bananas contain antinutrients, proteins that inhibit the actions of amylase, an enzyme that makes it possible for us to digest * They are also more healt hful. Green bananas contain proteins t hat inhibit amy- lase, an enzyme t hat makes it possible for us to digest complex carbohydrates. starch and other complex carbohydrates. Raw bananas are richer in potassium than cooked bananas; heating depletes potassium.
Buying This Food Look for: Bananas that will be good when you plan to eat them. Bananas with brown specks on the skin are ripe enough to eat immediately. Bananas with creamy yellow skin will be ready in a day or two. Bananas with mostly yellow skin and a touch of green at either end can be ripened at home and used in two or three days. Avoid: Overripe bananas whose skin has turned brown or split open. A grayish yellow skin means that the fruit has been damaged by cold storage. Bananas with soft spots under the skin may be rotten.
Storing This Food Store bananas that aren’t fully ripe at room temperature for a day or two. Like avocados, bananas are picked green, shipped hard to protect them from damage en route and then sprayed with ethylene gas to ripen them quickly. Untreated bananas release ethylene natu- rally to ripen the fruit and turn its starches to sugar, but natural ripening takes time. Artificial ripening happens so quickly that there is no time for the starches to turn into sugar. The bananas look ripe but they may taste bland and starchy. A few days at room temperature will give the starches a chance to change into sugars. Store ripe bananas in the refrigerator. The cold air will slow (but not stop) the natural enzyme action that ripens and eventually rots the fruit if you leave it at room temperature. Cold storage will darken the banana’s skin, since the chill damages cells in the peel and releases polyphenoloxidase, an enzyme that converts phenols in the banana peel to dark brown compounds, but the fruit inside will remain pale and tasty for several days.
Preparing This Food Do not slice or peel bananas until you are ready to use them. When you cut into the fruit, you tear its cell walls, releasing polyphenoloxidase, an enzyme that hastens the oxidation of phenols in the banana, producing brown pigments that darken the fruit. (Chilling a banana produces the same reaction because the cold damages cells in the banana peel.) You can slow the browning (but not stop it completely) by dipping raw sliced or peeled bananas into a solution of lemon juice or vinegar and water or by mixing the slices with citrus fruits in a fruit salad. Overripe, discolored bananas can be used in baking, where the color doesn’t matter and their intense sweetness is an asset.
What Happens When You Cook This Food When bananas are broiled or fried, they are cooked so quickly that there is very little change in color or texture. Even so, they will probably taste sweeter and have a more intense aroma than uncooked bananas. Heat liberates the volatile molecules that make the fruit taste and smell good.
How Other Kinds of Processing Affect This Food Drying. Drying removes water and concentrates the nutrients and calories in bananas. Bananas may be treated with compounds such as sulfur dioxide to inhibit polyphenoloxi- dase and keep the bananas from browning as they dry. People who are sensitive to sulfites may suffer severe allergic reactions, including anaphylactic shock, if they eat these treated bananas. Freezing. Fresh bananas freeze well but will brown if you try to thaw them at room tem- perature. To protect the creamy color, thaw frozen bananas in the refrigerator and use as quickly as possible.
Medical Uses and/or Benefits Lower risk of stroke. Various nutrition studies have attested to the power of adequate potassium to keep blood pressure within safe levels. For example, in the 1990s, data from the long-running Harvard School of Public Health/Health Professionals Follow-Up Study of male doctors showed that a diet rich in high-potassium foods such as bananas, oranges, and plantain may reduce the risk of stroke. In the study, the men who ate the higher number of potassium-rich foods (an average of nine servings a day) had a risk of stroke 38 percent lower than that of men who consumed fewer than four servings a day. In 2008, a similar survey at the Queen’s Medical Center (Honolulu) showed a similar protective effect among men and women using diuretic drugs (medicines that increase urination and thus the loss of potassium). Improved mood. Bananas and plantains are both rich in serotonin, dopamine, and other natural mood-elevating neurotransmitters—natural chemicals that facilitate the transmis- sion of impulses along nerve cells. Potassium benefits. Because potassium is excreted in urine, potassium-rich foods are often recommended for people taking diuretics. In addition, a diet rich in potassium (from food) is associated with a lower risk of stroke. A 1998 Harvard School of Public Health analysis of data from the long-running Health Professionals Study shows 38 percent fewer strokes among men who ate nine servings of high potassium foods a day vs. those who ate less than four servings. Among men with high blood pressure, taking a daily 1,000 mg potas- sium supplement—about the amount of potassium in one banana—reduced the incidence of stroke by 60 percent.
Adverse Effects Associated with This Food Digestive Problems. Unripe bananas contain proteins that inhibit the actions of amylase, an enzyme required to digest starch and other complex carbohydrates. Sulfite allergies. See How other kinds of processing affect this food. Latex-fruit syndrome. Latex is a milky fluid obtained from the rubber tree and used to make medical and surgical products such as condoms and protective latex gloves, as well as rub- ber bands, balloons, and toys; elastic used in clothing; pacifiers and baby bottle-nipples; chewing gum; and various adhesives. Some of the proteins in latex are allergenic, known to cause reactions ranging from mild to potentially life-threatening. Some of the proteins found naturally in latex also occur naturally in foods from plants such as avocados, bananas, chestnuts, kiwi fruit, tomatoes, and food and diet sodas sweetened with aspartame. Persons sensitive to these foods are likely to be sensitive to latex as well. NOTE : The National Insti- tute of Health Sciences, in Japan, also lists the following foods as suspect: Almonds, apples, apricots, bamboo shoots, bell peppers, buckwheat, cantaloupe, carrots, celery, cherries, chestnuts, coconut, figs, grapefruit, lettuce, loquat, mangoes, mushrooms, mustard, nectar- ines, oranges, passion fruit, papaya, peaches, peanuts, peppermint, pineapples, potatoes, soybeans, strawberries, walnuts, and watermelon.
Food/Drug Interactions Monoamine oxidase (MAO) inhibitors. Monoamine oxidase inhibitors are drugs used to treat depression. They inactivate naturally occurring enzymes in your body that metabolize tyra- mine, a substance found in many fermented or aged foods. Tyramine constricts blood vessels and increases blood pressure. If you eat a food containing tyramine while you are taking an M AO inhibitor, you cannot effectively eliminate the tyramine from your body. The result may be a hypertensive crisis. There have been some reports in the past of such reactions in people who have eaten rotten bananas or bananas stewed with the peel. False-positive test for tumors. Carcinoid tumors—which may arise from tissues of the endo- crine system, the intestines, or the lungs—secrete serotonin, a natural chemical that makes blood vessels expand or contract. Because serotonin is excreted in urine, these tumors are diagnosed by measuring the levels of serotonin by-products in the urine. Bananas contain large amounts of serotonin; eating them in the three days before a test for an endocrine tumor might produce a false-positive result, suggesting that you have the tumor when in fact you don’t. (Other foods high in serotonin are avocados, eggplant, pineapple, plums, tomatoes, and walnuts.)... bananas
The start of ‘dehydration’ is signalled by a person becoming thirsty. In normal circumstances, the drinking of water will relieve thirst and serious dehydration does not develop. In a temperate climate an adult will lose 1.5 litres or more a day from sweating, urine excretion and loss of ?uid through the lungs. In a hot climate the loss is much higher – up to 10 litres if a person is doing hard physical work. Even in a temperate climate, severe dehydration will occur if a person does not drink for two or three days. Large losses of ?uid occur with certain illnesses – for example, profuse diarrhoea; POLYURIA in diabetes or kidney failure (see KIDNEYS, DISEASES OF); and serious blood loss from, say, injury or a badly bleeding ULCER in the gastrointestinal tract. Severe thirst, dry lips and tongue, TACHYCARDIA, fast breathing, lightheadedness and confusion are indicative of serious dehydration; the individual can lapse into COMA and eventually die if untreated. Dehydration also results in a reduction in output of urine, which becomes dark and concentrated.
Prevention is important, especially in hot climates, where it is essential to drink water even if one is not thirsty. Replacement of salts is also vital, and a diet containing half a teaspoon of table salt to every litre of water drunk is advisable. If someone, particularly a child, suffers from persistent vomiting and diarrhoea, rehydration therapy is required and a salt-andglucose rehydration mixture (obtainable from pharmacists) should be taken. For those with severe dehydration, oral ?uids will be insu?cient and the affected person needs intravenous ?uids and, sometimes, admission to hospital, where ?uid intake and output can be monitored and rehydration measures safely controlled.... dehydration
For hip-joint disease, see under JOINTS, DISEASES OF.... hip-joint
All movable joints involve four structures: the bones whose junction forms the joint; a layer of cartilage covering the ends of these, making them smooth; a ?brous sheath, the capsule, thickened at various points into bands or ligaments, which hold the bones together; and, ?nally, the synovial membrane, which lines the capsule and produces a synovial ?uid, lubricating the movements of the joint. In addition, the bones are kept in position at the joints by the various muscles passing over them and by atmospheric pressure. Where the ends of the bones do not quite correspond, a subsidiary disc of ?bro-cartilage may help to adapt the ends of the bones more perfectly to each other. Larger cavities may be ?lled by movable pads of fat under the synovial membrane, giving additional protection to the joint.
Varieties After this main division of joints into those which are ?xed and those movable, the movable joints may be further subdivided. In gliding joints, such as the wrist and ankle, the bones have ?at surfaces capable of only a limited amount of movement. In hinge joints, such as the elbow and knee, movement takes place around one axis. Ball-and-socket joints, exempli?ed by the shoulder and hip, allow free movement in any direction. Subsidiary varieties are named according to the shape of the bones which enter the joint.... joints
Rarely, the UTERUS may be completely absent as a result of abnormal development. In such patients secondary sexual development is normal but MENSTRUATION is absent (primary amennorhoea). The chromosomal make-up of the patient must be checked (see CHROMOSOMES; GENES): in a few cases the genotype is male (testicular feminisation syndrome). No treatment is available, although the woman should be counselled.
The uterus develops as two halves which fuse together. If the fusion is incomplete, a uterine SEPTUM results. Such patients with a double uterus (uterus didelphys) may have fertility problems which can be corrected by surgical removal of the uterine septum. Very rarely there may be two uteri with a double vagina.
The uterus of most women points forwards (anteversion) and bends forwards (ante?exion). However, about 25 per cent of women have a uterus which is pointed backwards (retroversion) and bent backwards (retro?exion). This is a normal variant and very rarely gives rise to any problems. If it does, the attitude of the uterus can be corrected by an operation called a ventrosuspension.
Endometritis The lining of the uterine cavity is called the ENDOMETRIUM. It is this layer that is partially shed cyclically in women of reproductive age giving rise to menstruation. Infection of the endometrium is called endometritis and usually occurs after a pregnancy or in association with the use of an intrauterine contraceptive device (IUCD – see CONTRACEPTION). The symptoms are usually of pain, bleeding and a fever. Treatment is with antibiotics. Unless the FALLOPIAN TUBES are involved and damaged, subsequent fertility is unaffected. Very rarely, the infection is caused by TUBERCULOSIS. Tuberculous endometritis may destroy the endometrium causing permanent amenorrhoea and sterility.
Menstrual disorders are common. Heavy periods (menorrhagia) are often caused by ?broids (see below) or adenomyosis (see below) or by anovulatory cycles. Anovulatory cycles result in the endometrium being subjected to unopposed oestrogen stimulation and occasionally undergoing hyperplasia. Treatment is with cyclical progestogens (see PROGESTOGEN) initially. If this form of treatment fails, endoscopic surgery to remove the endometrium may be successful. The endometrium may be removed using LASER (endometrial laser ablation) or electrocautery (transcervical resection of endometrium). Hysterectomy (see below) will cure the problem if endoscopic surgery fails. Adenomyosis is a condition in which endometrial tissue is found in the muscle layer (myometrium) of the uterus. It usually presents as heavy and painful periods, and occasionally pain during intercourse. Hysterectomy is usually required.
Oligomenorhoea (scanty or infrequent periods) may be caused by a variety of conditions including thyroid disease (see THYROID GLAND, DISEASES OF). It is most commonly associated with usage of the combined oral contraceptive pill. Once serious causes have been eliminated, the patient should be reassured. No treatment is necessary unless conception is desired, in which case the patient may require induction of ovulation.
Primary amenorrhoea means that the patient has never had a period. She should be investigated, although usually it is only due to an inexplicable delay in the onset of periods (delayed menarche) and not to any serious condition. Secondary amenorrhoea is the cessation of periods after menstruation has started. The most common cause is pregnancy. It may be also caused by endocrinological or hormonal problems, tuberculous endometritis, emotional problems and severe weight loss. The treatment of amenorrhoea depends on the cause.
Dysmenorrhoea, or painful periods, is the most common disorder; in most cases the cause is unknown, although the disorder may be due to excessive production of PROSTAGLANDINS.
Irregular menstruation (variations from the woman’s normal menstrual pattern or changes in the duration of bleeding or the amount) can be the result of a disturbance in the balance of OESTROGENS and PROGESTERONE hormone which between them regulate the cycle. For some time after the MENARCHE or before the MENOPAUSE, menstruation may be irregular. If irregularity occurs in a woman whose periods are normally regular, it may be due to unsuspected pregnancy, early miscarriage or to disorders in the uterus, OVARIES or pelvic cavity. The woman should seek medical advice.
Fibroids (leiomyomata) are benign tumours arising from the smooth muscle layer (myometrium) of the uterus. They are found in 80 per cent of women but only a small percentage give rise to any problems and may then require treatment. They may cause heavy periods and occasionally pain. Sometimes they present as a mass arising from the pelvis with pressure symptoms from the bladder or rectum. Although they can be shrunk medically using gonadorelin analogues, which raise the plasma concentrations of LUTEINISING HORMONE and FOLLICLE-STIMULATING HORMONE, this is not a long-term solution. In any case, ?broids only require treatment if they are large or enlarging, or if they cause symptoms. Treatment is either myomectomy (surgical removal) if fertility is to be retained, or a hysterectomy.
Uterine cancers tend to present after the age of 40 with abnormal bleeding (intermenstrual or postmenopausal bleeding). They are usually endometrial carcinomas. Eighty per cent present with early (Stage I) disease. Patients with operable cancers should be treated with total abdominal hysterectomy and bilateral excision of the ovaries and Fallopian tubes. Post-operative RADIOTHERAPY is usually given to those patients with adverse prognostic factors. Pre-operative radiotherapy is still given by some centres, although this practice is now regarded as outdated. PROGESTOGEN treatment may be extremely e?ective in cases of recurrence, but its value remains unproven when used as adjuvant treatment. In 2003 in England and Wales, more than 2,353 women died of uterine cancer.
Disorders of the cervix The cervix (neck of the womb) may produce an excessive discharge due to the presence of a cervical ectopy or ectropion. In both instances columnar epithelium – the layer of secreting cells – which usually lines the cervical canal is exposed on its surface. Asymptomatic patients do not require treatment. If treatment is required, cryocautery – local freezing of tissue – is usually e?ective.
Cervical smears are taken and examined in the laboratory to detect abnormal cells shed from the cervix. Its main purpose is to detect cervical intraepithelial neoplasia (CIN) – the presence of malignant cells in the surface tissue lining the cervix – since up to 40 per cent of women with this condition will develop cervical cancer if the CIN is left untreated. Women with abnormal smears should undergo colposcopy, a painless investigation using a low-powered microscope to inspect the cervix. If CIN is found, treatment consists of simply removing the area of abnormal skin, either using a diathermy loop or laser instrument.
Unfortunately, cervical cancer remains the most common of gynaecological cancers. The most common type is squamous cell carcinoma and around 4,000 new cases (all types) are diagnosed in England and Wales every year. As many as 50 per cent of the women affected may die from the disease within ?ve years. Cervical cancer is staged clinically in four bands according to how far it has extended, and treatment is determined by this staging. Stage I involves only the mucosal lining of the cervix and cone BIOPSY may be the best treatment in young women wanting children. In Stage IV the disease has spread beyond the cervix, uterus and pelvis to the URINARY BLADDER or RECTUM. For most women, radiotherapy or radical Wertheim’s hysterectomy – the latter being preferable for younger women – is the treatment of choice if the cancer is diagnosed early, both resulting in survival rates of ?ve years in 80 per cent of patients. Wertheim’s hysterectomy is a major operation in which the uterus, cervix, upper third of vagina and the tissue surrounding the cervix are removed together with the LYMPH NODES draining the area. The ovaries may be retained if desired. Patients with cervical cancer are treated by radiotherapy, either because they present too late for surgery or because the surgical skill to perform a radical hysterectomy is not available. These operations are best performed by gynaecological oncologists who are gynaecological surgeons specialising in the treatment of gynaecological tumours. The role of CHEMOTHERAPY in cervical and uterine cancer is still being evaluated.
Prolapse of the uterus is a disorder in which the organ drops from its normal situation down into the vagina. First-degree prolapse is a slight displacement of the uterus, second-degree a partial displacement and third-degree when the uterus can be seen outside the VULVA. It may be accompanied by a CYSTOCOELE (the bladder bulges into the front wall of the vagina), urethrocoele (the urethra bulges into the vagina) and rectocoele (the rectal wall bulges into the rear wall of the vagina). Prolapse most commonly occurs in middle-aged women who have had children, but the condition is much less common now than in the past when prenatal and obstetric care was poor, women had more pregnancies and their general health was poor. Treatment is with pelvic exercises, surgical repair of the vagina or hysterectomy. If the woman does not want or is not ?t for surgery, an internal support called a pessary can be ?tted – and changed periodically.
Vertical section of female reproductive tract (viewed from front) showing sites of common gynaecological disorders.
Hysterectomy Many serious conditions of the uterus have traditionally been treated by hysterectomy, or removal of the uterus. It remains a common surgical operation in the UK, but is being superseded in the treatment of some conditions, such as persistent MENORRHAGIA, with endometrial ablation – removal of the lining of the uterus using minimally invasive techniques, usually using an ENDOSCOPE and laser. Hysterectomy is done to treat ?broids, cancer of the uterus and cervix, menorrhagia, ENDOMETRIOSIS and sometimes for severely prolapsed uterus. Total hysterectomy is the usual type of operation: it involves the removal of the uterus and cervix and sometimes the ovaries. After hysterectomy a woman no longer menstruates and cannot become pregnant. If the ovaries have been removed as well and the woman had not reached the menopause, hormone replacement therapy (HRT – see MENOPAUSE) should be considered. Counselling helps the woman to recover from the operation which can be an emotionally challenging event for many.... uterus, diseases of
Surgeons use the term to refer to the freeing of an organ or structure from surrounding connective tissue and fibrous adhesions (bands of tissue joining normally unconnected parts of the body).... mobilization
– the corpus callosum. Other clefts or ?ssures (sulci) make deep impressions, dividing the cerebrum into lobes. The lobes of the cerebrum are the frontal lobe in the forehead region, the parietal lobe on the side and upper part of the brain, the occipital lobe to the back, and the temporal lobe lying just above the region of the ear. The outer 3 mm of the cerebrum is called the cortex, which consists of grey matter with the nerve cells arranged in six layers. This region is concerned with conscious thought, sensation and movement, operating in a similar manner to the more primitive areas of the brain except that incoming information is subject to much greater analysis.
Numbers of shallower infoldings of the surface, called furrows or sulci, separate raised areas called convolutions or gyri. In the deeper part, the white matter consists of nerve ?bres connecting di?erent parts of the surface and passing down to the lower parts of the brain. Among the white matter lie several rounded masses of grey matter, the lentiform and caudate nuclei. In the centre of each cerebral hemisphere is an irregular cavity, the lateral ventricle, each of which communicates with that on the other side and behind with the third ventricle through a small opening, the inter-ventricular foramen, or foramen of Monro.
BASAL NUCLEI Two large masses of grey matter embedded in the base of the cerebral hemispheres in humans, but forming the chief part of the brain in many animals. Between these masses lies the third ventricle, from which the infundibulum, a funnel-shaped process, projects downwards into the pituitary body, and above lies the PINEAL GLAND. This region includes the important HYPOTHALAMUS.
MID-BRAIN or mesencephalon: a stalk about 20 mm long connecting the cerebrum with the hind-brain. Down its centre lies a tube, the cerebral aqueduct, or aqueduct of Sylvius, connecting the third and fourth ventricles. Above this aqueduct lie the corpora quadrigemina, and beneath it are the crura cerebri, strong bands of white matter in which important nerve ?bres pass downwards from the cerebrum. The pineal gland is sited on the upper part of the midbrain.
PONS A mass of nerve ?bres, some of which run crosswise and others are the continuation of the crura cerebri downwards.
CEREBELLUM This lies towards the back, underneath the occipital lobes of the cerebrum.
MEDULLA OBLONGATA The lowest part of the brain, in structure resembling the spinal cord, with white matter on the surface and grey matter in its interior. This is continuous through the large opening in the skull, the foramen magnum, with the spinal cord. Between the medulla, pons, and cerebellum lies the fourth ventricle of the brain.
Structure The grey matter consists mainly of billions of neurones (see NEURON(E)) in which all the activities of the brain begin. These cells vary considerably in size and shape in di?erent parts of the brain, though all give o? a number of processes, some of which form nerve ?bres. The cells in the cortex of the cerebral hemispheres, for example, are very numerous, being set in layers ?ve or six deep. In shape these cells are pyramidal, giving o? processes from the apex, from the centre of the base, and from various projections elsewhere on the cell. The grey matter is everywhere penetrated by a rich supply of blood vessels, and the nerve cells and blood vessels are supported in a ?ne network of ?bres known as neuroglia.
The white matter consists of nerve ?bres, each of which is attached, at one end, to a cell in the grey matter, while at the other end it splits up into a tree-like structure around another cell in another part of the grey matter in the brain or spinal cord. The ?bres have insulating sheaths of a fatty material which, in the mass, gives the white matter its colour; they convey messages from one part of the brain to the other (association ?bres), or, grouped into bundles, leave the brain as nerves, or pass down into the spinal cord where they end near, and exert a control upon, cells from which in turn spring the nerves to the body.
Both grey and white matter are bound together by a network of cells called GLIA which make up 60 per cent of the brain’s weight. These have traditionally been seen as simple structures whose main function was to glue the constituents of the brain together. Recent research, however, suggests that glia are vital for growing synapses between the neurons as they trigger these cells to communicate with each other. So they probably participate in the task of laying down memories, for which synapses are an essential key. The research points to the likelihood that glial cells are as complex as neurons, functioning biochemically in a similar way. Glial cells also absorb potassium pumped out by active neurons and prevent levels of GLUTAMATE – the most common chemical messenger in the brain – from becoming too high.
The general arrangement of ?bres can be best understood by describing the course of a motor nerve-?bre. Arising in a cell on the surface in front of the central sulcus, such a ?bre passes inwards towards the centre of the cerebral hemisphere, the collected mass of ?bres as they lie between the lentiform nucleus and optic thalamus being known as the internal capsule. Hence the ?bre passes down through the crus cerebri, giving o? various small connecting ?bres as it passes downwards. After passing through the pons it reaches the medulla, and at this point crosses to the opposite side (decussation of the pyramids). Entering the spinal cord, it passes downwards to end ?nally in a series of branches (arborisation) which meet and touch (synapse) similar branches from one or more of the cells in the grey matter of the cord (see SPINAL CORD).
BLOOD VESSELS Four vessels carry blood to the brain: two internal carotid arteries in front, and two vertebral arteries behind. These communicate to form a circle (circle of Willis) inside the skull, so that if one is blocked, the others, by dilating, take its place. The chief branch of the internal carotid artery on each side is the middle cerebral, and this gives o? a small but very important branch which pierces the base of the brain and supplies the region of the internal capsule with blood. The chief importance of this vessel lies in the fact that the blood in it is under especially high pressure, owing to its close connection with the carotid artery, so that haemorrhage from it is liable to occur and thus give rise to stroke. Two veins, the internal cerebral veins, bring the blood away from the interior of the brain, but most of the small veins come to the surface and open into large venous sinuses, which run in grooves in the skull, and ?nally pass their blood into the internal jugular vein that accompanies the carotid artery on each side of the neck.
MEMBRANES The brain is separated from the skull by three membranes: the dura mater, a thick ?brous membrane; the arachnoid mater, a more delicate structure; and the pia mater, adhering to the surface of the brain and containing the blood vessels which nourish it. Between each pair is a space containing ?uid on which the brain ?oats as on a water-bed. The ?uid beneath the arachnoid membrane mixes with that inside the ventricles through a small opening in the fourth ventricle, called the median aperture, or foramen of Magendie.
These ?uid arrangements have a great in?uence in preserving the brain from injury.... divisions
Several diseases and conditions are treated under separate headings. (See APPENDICITIS; CHOLERA; COLITIS; CONSTIPATION; CROHN’S DISEASE; DIARRHOEA; DYSENTERY; ENTERIC FEVER; HAEMORRHOIDS; HERNIA; INFLAMMATORY BOWEL DISEASE (IBD); ILEITIS; INTUSSUSCEPTION; IRRITABLE BOWEL SYNDROME (IBS); PERITONITIS; RECTUM, DISEASES OF; ULCERATIVE COLITIS.)
In?ammation of the outer surface is called peritonitis, a serious disease. That of the inner surface is known generally as enteritis, in?ammation of special parts receiving the names of colitis, appendicitis, irritable bowel syndrome (IBS) and in?ammatory bowel disease (IBD). Enteritis may form the chief symptom of certain infective diseases: for example in typhoid fever (see ENTERIC FEVER), cholera and dysentery. It may be acute, although not connected with any de?nite organism, when, if severe, it is a very serious condition, particularly in young children. Or it may be chronic, especially as the result of dysentery, and then constitutes a less serious if very troublesome complaint.
Perforation of the bowel may take place as the result either of injury or of disease. Stabs and other wounds which penetrate the abdomen may damage the bowel, and severe blows or crushes may tear it without any external wound. Ulceration, as in typhoid fever, or, more rarely, in TUBERCULOSIS, may cause an opening in the bowel-wall also. Again, when the bowel is greatly distended above an obstruction, faecal material may accumulate and produce ulcers, which rupture with the ordinary movements of the bowels. Whatever the cause, the symptoms are much the same.
Symptoms The contents of the bowel pass out through the perforation into the peritoneal cavity, and set up a general peritonitis. In consequence, the abdomen is painful, and after a few hours becomes extremely tender to the touch. The abdomen swells, particularly in its upper part, owing to gas having passed also into the cavity. Fever and vomiting develop and the person passes into a state of circulatory collapse or SHOCK. Such a condition may be fatal if not properly treated.
Treatment All food should be withheld and the patient given intravenous ?uids to resuscitate them and then to maintain their hydration and electrolyte balance. An operation is urgently necessary, the abdomen being opened in the middle line, the perforated portion of bowel found, the perforation stitched up, and appropriate antibiotics given.
Obstruction means a stoppage to the passage down the intestine of partially digested food. Obstruction may be acute, when it comes on suddenly with intense symptoms; or it may be chronic, when the obstructing cause gradually increases and the bowel becomes slowly more narrow until it closes altogether; or subacute, when obstruction comes and goes until it ends in an acute attack. In chronic cases the symptoms are milder in degree and more prolonged.
Causes Obstruction may be due to causes outside the bowel altogether, for example, the pressure of tumours in neighbouring organs, the twisting around the bowel of bands produced by former peritonitis, or even the twisting of a coil of intestine around itself so as to cause a kink in its wall. Chronic causes of the obstruction may exist in the wall of the bowel itself: for example, a tumour, or the contracting scar of an old ulcer. The condition of INTUSSUSCEPTION, where part of the bowel passes inside of the part beneath it, in the same way as one turns the ?nger of a glove outside in, causes obstruction and other symptoms. Bowel within a hernia may become obstructed when the hernia strangulates. Finally some body, such as a concretion, or the stone of some large fruit, or even a mass of hardened faeces, may become jammed within the bowel and stop up its passage.
Symptoms There are four chief symptoms: pain, vomiting, constipation and swelling of the abdomen.
Treatment As a rule the surgeon opens the abdomen, ?nds the obstruction and relieves it or if possible removes it altogether. It may be necessary to form a COLOSTOMY or ILEOSTOMY as a temporary or permanent measure in severe cases.
Tumours are rare in the small intestine and usually benign. They are relatively common in the large intestine and are usually cancerous. The most common site is the rectum. Cancer of the intestine is a disease of older people; it is the second most common cancer (after breast cancer) in women in the United Kingdom, and the third most common (after lung and prostate) in men. Around 25,000 cases of cancer of the large intestine occur in the UK annually, about 65 per cent of which are in the colon. A history of altered bowel habit, in the form of increasing constipation or diarrhoea, or an alternation of these, or of bleeding from the anus, in a middle-aged person is an indication for taking medical advice. If the condition is cancer, then the sooner it is investigated and treated, the better the result.... intestine, diseases of
Motion sickness is caused by the effect of repetitive movement on the organ of balance in the inner ear. Factors such as anxiety, a fume-laden atmosphere, or the sight of food may make the condition worse. So, too, can focusing on nearby objects; sufferers should look at a point on the horizon.
Motion sickness may be prevented or controlled by antiemetic drugs or by acupressure bands worn on the wrist.... motion sickness
Shoulder-blade or scapula. A ?at bone, about as large as the ?at hand and ?ngers, placed on the upper and back part of the With the arm hanging by the side, the scapula extends from the second to the seventh rib, but, as the arm is raised and lowered, it slides freely over the back of the chest. On the rear surface of the bone is a strong process, the spine of the scapula. This arches upwards and forwards into the acromion process. The latter forms the bony prominence on the top of the shoulder, where it unites in a joint with the outer end of the clavicle.... shoulder
Tendon injuries are one of the hazards of sports (see SPORTS MEDICINE). They usually result from indirect violence, or overuse, rather than direct violence.
Rupture usually results from the sudden application of an unbalanced load. Thus, complete rupture of the Achilles tendon is common in taking an awkward step backwards playing squash. There is sudden pain; the victim is often under the impression that he or she has received a blow. This is accompanied by loss of function, and a gap may be felt in the tendon.
Partial Rupture is also accompanied by pain, but there is no breach of continuity or complete loss of function. Treatment of a complete rupture usually means surgical repair followed by immobilisation of the tendon in plaster of Paris for six weeks. Partial rupture usually responds to physiotherapy and immobilisation, but healing is slow.... tendon
The size and shape and general appearance of the breasts may vary during the menstrual cycle, during pregnancy and lactation, and after the menopause.
During pregnancy, oestrogen and progesterone, secreted by the ovary and placenta, cause the milkproducing glands to develop and become active and the nipple to become larger.
Just before and after
childbirth, the glands in the breast produce a watery fluid known as colostrum.
This fluid is replaced by milk a few days later.
Milk production and its release is stimulated by the hormone prolactin.... breast
Cirrhosis may go unrecognized until symptoms such as mild jaundice, oedema, and vomiting of blood develop. There may be enlargement of the liver and spleen and, in men, enlargement of the breasts and loss of body hair due to an imbalance in sex hormones caused by liver failure. Complications of cirrhosis include ascites, oesophageal varices, and hepatoma. Treatment is focused on slowing the rate at which liver cells are being damaged, if possible by treating the cause. In some cases, however, the condition progresses and a liver transplant may be considered.... cirrhosis
ortho- A prefix meaning normal, correct, or straight, as in orthopaedics, a branch of surgery concerned with correcting disorders of the bones and joints.
orthodontic appliances Fixed or removable devices, commonly known as braces, worn to correct malocclusion, or to reposition overcrowded or buck teeth. Usually fitted during childhood and adolescence, they move teeth using sustained gentle pressure. A fixed appliance has brackets attached to the teeth through which an arch wire is threaded and tightened to exert pressure. These are usually kept in place for about a year, after which time a retainer plate may be needed to hold the teeth in place until tooth and jaw growth has finished.
Removable appliances, consisting of a plastic plate with attachments that anchor over the back teeth, are used when only one or a few teeth need correcting. They apply force by means of springs, wire bows, screws, or rubber bands fitted to the plate.... ort
The cerebellum is essential for the maintenance of muscle tone, balance, and the synchronization of activity in groups of muscles under voluntary control, converting muscular contractions into smooth coordinated movement. It does not, however, initiate movement and plays no part in the perception of conscious sensations or in intelligence. —cerebellar adj.... cerebellum
First- and second-degree haemorrhoids may respond to bowel regulation using a high-fibre diet and faecal softening agents. If bleeding persists, elastic bands may be applied or a sclerosing agent may be injected around the swollen cushions to eradicate them. Third-degree haemorrhoids often require surgery (see haemorrhoidectomy), especially if they become *strangulated (producing severe pain and further enlargement).
External haemorrhoids are either prolapsed internal haemorrhoids or – more often – *perianal haematomas or the residual skin tags remaining after a perianal haematoma has healed.... haemorrhoids
—trabecular adj.... trabecula
Health Encyclopedia