Rna interference Health Dictionary

Rna Interference: From 1 Different Sources


(RNAi) a mechanism, either natural or the result of biotechnological manipulation, by which *RNA suppresses or interferes with the expression of a gene or genes. Its possible role in gene-specific therapy is under investigation.
Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Anabolic Steroids

The nitrogen-retaining e?ect of ANDROGEN, a steroid hormone, is responsible for the larger muscle mass of the male. This is called an anabolic e?ect. Attempts have been made to separate the anabolic effects of hormones from their virilising effects (see VIRILISATION), but these have been only partially successful. Thus, anabolic steroids have the property of protein-building so that when taken, they lead to an increase in muscle bulk and strength. All the anabolic steroids have some androgenic activity but they cause less virilisation than androgens in women. Androgenic side-effects may result from any of these anabolic compounds, especially if they are given for prolonged periods: for this reason they should all be used with caution in women, and are contraindicated in men with prostatic carcinoma. Jaundice due to stasis of bile in the intrahepatic canaliculi is a hazard, and the depression of pituitary gonadotrophin production is a possible complication.

Anabolic steroids have been used to stimulate protein anabolism in debilitating illness, and to promote growth in children with pituitary dwar?sm and other disorders associated with interference of growth. Stimulation of protein anabolism may also be of value in acute renal failure, and the retention of nitrogen and calcium is of probable bene?t to patients with OSTEOPOROSIS and to patients receiving corticosteroid therapy. Anabolic steroids may stimulate bone-marrow function in hypoplastic ANAEMIA.

They have been widely abused by athletes and body-builders aiming to improve their strength, stamina, speed or body size. However, there are considerable doubts over their e?cacy, with little experimental evidence that they work. Dangerous adverse effects include precocious myocardial infarction (see HEART, DISEASES OF – Coronary thrombosis), DIABETES MELLITUS, liver disease, precocious carcinoma of the prostate, acne, and severe psychiatric disorders. Anabolic steroids should not be used by athletes, who face bans from o?cial competitions if they take them.

The anabolic steroids in therapeutic use include nandrolone and stanozolol.... anabolic steroids

Cardiac Arrhythmia

Abnormal rhythm of the heartbeat. Most commonly seen after someone has had a myocardial infarction, but also present in some normal individuals – especially if they have taken a lot of co?ee or other stimulant – and in those with a congenital abnormality of the heart-muscle conducting system. The cause is interference in the generation or transmission of electrical impulses through the heart’s conducting system. Occasional isolated irregular beats (ectopic beats) do not necessarily mean that conduction is faulty. Arrhythmias can be classi?ed as tachycardias (more than 100 beats a minute) or bradycardias (slower than 60 beats a minute). Heartbeats may be regular or irregular. (See HEART, DISEASES OF.)... cardiac arrhythmia

Cardiac Pacemaker

The natural pacemaker is the sinuatrial node, found at the base of the heart. The heart normally controls its rate and rhythm; heart block occurs when impulses cannot reach all parts of the heart. This may lead to ARRHYTHMIA, or even cause the heart to stop (see HEART, DISEASES OF). Arti?cial pacemakers may then be used; in the United Kingdom these are required for around one person in every 2,000 of the population. Usually powered by mercury or lithium batteries, and lasting up to 15 years, they are either ?xed to the outside of the chest or implanted in the armpit, and connected by a wire passing through a vein in the neck to the heart. Normally adjusted to deliver 65–75 impulses a minute, they also ensure a regular cardiac rhythm. Patients with pacemakers may be given a driving licence provided that their vehicle is not likely to be a source of danger to the public, and that they are receiving adequate and regular medical supervision from a cardiologist.

Although there are numerous possible sources of electrical interference with pacemakers, the overall risks are slight. Potential sources include anti-theft devices, airport weapon detectors, surgical diathermy, ultrasound, and short-wave heat treatment. Nevertheless, many pacemaker patients lead active and ful?lling lives.... cardiac pacemaker

Conservative Treatment

Medical treatment which involves the minimum of active interference by the practitioner. For example, a disc lesion in the back might be treated by bed rest in contrast to surgical intervention to remove the damaged disc.... conservative treatment

Drop Attack

A brief episode affecting the nervous system that causes the person to fall suddenly. There is no loss of consciousness. The loss of tone in the muscles, responsible for the fall, may persist for several hours; in such cases moving the patient or applying pressure to the soles of the feet may restore muscle tone. In most cases, however, recovery is immediate. The cause is probably a temporary interference with the blood supply to the brain. In others there may be some disturbance of the vestibular apparatus which controls the balance of the body. (See EAR, DISEASES OF; TRANSIENT ISCHAEMIC ATTACKS OR EPISODES (TIA, TIE).)... drop attack

Fatty Degeneration

As a result of ANAEMIA, interference with blood or nerve supply, or because of the action of various poisons, body cells may undergo abnormal changes accompanied by the appearance in their substance of fat droplets.... fatty degeneration

Cancer - Breast

Commonest form of cancer in women. Overall mortality remains about 50 per cent at five years. Appears to run in families. Strikes hard unmarried women. Married women who have no children. Those who do not nurse their babies, or who are infertile and have no child before thirty. Eight out of ten chest lumps are benign.

Symptoms. A small lump comes to light while washing, a discharge from the nipple, change in nipple size and colour, irregular contour of the breast surface. Though tissue change is likely to be a cyst, speedy diagnosis and treatment are necessary. Some hospital physicians and surgeons are known to view favourably supportive herbal aids, and do not always think in terms of radical mastectomy. Dr Finlay Ellingwood, Chicago physician (1916) cured a case by injection of one dram Echinacea root extract twice a week into the surrounding tissues.

The condition is believed to be due to a number of causes including suppression of ovulation and oestrogen secretion in pregnant and lactating women. A high fat diet is suspected of interference with the production of oestrogen. Some women are constitutionally disposed to the condition which may be triggered by trauma or emotional shock. Increase in incidence in older women has been linked with excessive sugar consumption. “Consumption overwhelms the pancreas which has to ‘push it out’ to all parts of the body (when broken down by the digestive process) whether they need it or not. The vital organs are rationed according to their requirements of nutrients from the diet. What is left over has to ‘go into store elsewhere’. And the breast is forced to take its share and store it. If it gets too much, for too long, it may rebel!” (Stephen Seely, Department of Bacteriology and Virology, Manchester)

“Women who nurse their babies less than one month are at an increased risk for breast cancer. The longer a woman breast-feeds – no matter what her age – the more the risk decreases. (Marion Tompson, co-founder, The La Leche League, in the American Journal of Epidemiology)

Lactation reduces the risk of pre-menopausal breast cancer. (Newcomb P.A. et al New England Journal of Medicine, 330 1994)

There is currently no treatment to cure metastatic breast cancer. In spite of chemotherapy, surgery and radiotherapy survival rate has not diminished. Herbs not only have a palliative effect but, through their action on hormone function offer a positive contribution towards overcoming the condition. Their activity has been widely recorded in medical literature. Unlike cytotoxic drugs, few have been known to cause alopecia, nausea, vomiting or inflammation of the stomach.

Treatment by a general medical practitioner or oncologist.

Special investigations. Low radiation X-ray mammography to confirm diagnosis. Test for detection of oestrogen receptor protein.

Treatment. Surgery may be necessary. Some patients may opt out from strong personal conviction, choosing a rigid self-disciplined approach – the Gentle Way. Every effort is made to build up the body’s natural defences (immune system).

An older generation of herbalists believed tissue change could follow a bruise on the breast, which should not be neglected but immediately painted with Tincture Arnica or Tincture Bellis perennis.

Vincristine, an alkaloid from Vinca rosea (Catharanthus roseus) is used by the medical profession as an anti-neoplastic and anti-mitotic agent to inhibit cell division.

Of possible therapeutic value. Blue Flag root, Burdock root, Chaparral, Clivers, Comfrey root, Echinacea, Figwort, Gotu Kola, Marshmallow root, Mistletoe, Myrrh, Prickly Ash bark, Red Clover, Thuja, Wild Violet, Yellow Dock.

Tea. Equal parts: Red Clover, Clivers, Gotu Kola, Wild Violet. 1 heaped teaspoon to each cup boiling water; infuse 5-15 minutes. 3 or more cups daily.

Decoctions. Echinacea, Blue Flag root, Queen’s Delight, Yellow Dock.

Tablets/capsules. Blue Flag root, Echinacea, Poke root, Mistletoe.

Formula. Echinacea 2; Gotu Kola 1; Poke root 1; Mistletoe 1; Vinca rosea 1. Mix. Dose: Powders: 500mg (two 00 capsules or one-third teaspoon). Liquid extracts: 1 teaspoon. Tinctures: 2 teaspoons. Thrice daily and at bedtime. According to progress of the disease, increase dosage as tolerated.

Maria Treben’s tea. Parts: Marigold (3), Yarrow 1; Nettles 1. Mix. 2 teaspoons to each cup boiling water. 1 cup as many times daily as tolerated.

William Boericke, M.D. recommends Houseleek. E.H. Ruddock M.D. favours Figwort.

Topical. Treatments believed to be of therapeutic value or for use as a soothing application.

(1) Cold poultice: Comfrey root.

(2) Poultice of fresh Marshmallow root pulped in juicer.

(3) Injection of Extract Greater Celandine (Chelidonium), locally, gained a reputation in the Eclectic school.

(4) The action of Blood root (Sanguinaria) is well known as a paint or injection.

(5) Ragwort poultice: 2oz Ragwort boiled in half a pint potato water for 15 minutes. See: POULTICE.

(6) Popular Russian traditional remedy: Badiaga (Spongilla fluviatilis), fresh water sponge gathered in the autumn; dried plant rubbed to a powder. Poultice.

(7) Maria Treben’s Poultice: Carefully washed fresh Plantain leaves, pulped, and applied direct to the lesion.

(8) If lymph glands are affected, apply Plantain poultice to glands.

(9) Dr Brandini’s treatment. Dr Brandini, Florence, used 4 grains Citric Acid (prepared from lemons) in 1oz (30ml) water for ulcerated cancer of the breast considered incurable. “The woman’s torments were so distressing that neither she nor other patients could get any rest. Applying lint soaked in the solution, relief was instantaneous. Repeated, it was successful.”

(10) Circuta leaves. Simmered till soft and mixed with Slippery Elm bark powder as a poultice morning and night.

(11) Decoction. Simmer gently Yellow Dock roots, fine cut or powdered, 1oz to 1 pint, 20 minutes. Saturate lint or suitable material and apply.

(12) Yellow Dock ointment. Half ounce Lobelia seed, half ounce Yellow Dock root powder. Baste into an ointment base. See: OINTMENT BASE.

(13) Infusion, for use as a wash. Equal parts: Horsetail, Red Clover, Raspberry leaves. 1oz to 1 pint boiling water infuse 15 minutes.

(14) Dr Christopher’s Ointment. Half an ounce White Oak, half an ounce Garden Sage, half an ounce Tormentil, half an ounce Horsetail, half an ounce Lemon Balm. Method: Boil gently half an hour in quart water, strain. Reduce to half a pint by simmering. Add half a pound honey. Bring to boil. Skim off scum. Allow cool. Apply: twice daily on sores.

(15) Dr Finlay Ellingwood. Poke root juice. “Fresh juice from the stems, leaves and roots applied directly to diseased tissue. Exercises a selective action; induces liquefaction and promotes removal, sometimes healing the open wound and encouraging scar formation. Masses of such tissue have been known to be destroyed in a few weeks with only a scar, with no other application but the fresh juice. Produces pain at first, but is otherwise harmless.”

(16) Lesion painted with Mandrake resin. (American Podophyllum)

(17) Dust affected parts with Comfrey powder. Mucilage from Comfrey powder or crushed root with the aid of a little milk. See: COMFREY.

(18) Dr Samuel Thomson’s Cancer Plaster. “Take heads of Red Clover and fill a kettle. Boil in water for one hour. Remove and fill kettle with fresh flower heads. Boil as before in the same liquor. Strain and press heads to express all the liquor. Simmer over a low fire till of the consistency of tar. It must not burn. Spread over a piece of suitable material.”

(19) Wipe affected area with cut Houseleek. (Dr Wm Boericke)

(20) Chinese Herbalism. Take 1-2 Liang pulverised liao-ko-wang (Wickstroemia indica), mix with cold boiled water or rice wine for local compress. Also good for mastitis.

(21) Italian women once used an old traditional remedy – Fenugreek tea.

(22) A clinical trial of Vitamin D provided encouraging results. Patients with locally advanced breast cancer were given a highly active Vitamin D analogue cream to rub on their tumours. “It was effective in one third of the tumours,” said Professor Charles Coombes, clinical oncologist, Charing Cross Hospital, London.

Diet. “A diet rich in cereal products (high in dietary fibre) and green leafy vegetables (antioxidants) would appear to offer women some protection against breast cancer due to the relation between fibre and oestrogen metabolism. Meat-free diet. In a study of 75 adolescent girls, vegetarians were found to have higher levels of a hormone that women suffering from breast cancer often lack. (Cancer Research) Supplements. Daily. Chromium. Selenium (600mcg). Zinc chelate (100mg morning and evening). Beta carotene. “Low levels of Selenium and Vitamins A and E are shown in breast cancer cases.” (British Journal of Cancer 49: 321-324, 1984).

Vitamins A and D inhibit virus penetration in healthy cell walls. Multivitamin combinations should not include Vitamin B12, production of which in the body is much increased in cancerous conditions. Vitamins B-complex and C especially required.

Note: A link between sugar consumption and breast cancer has been reported by some authorities who suggest that countries at the top of the mortality table are the highest also in sugar consumption; the operative factor believed to be insulin.

Screening. Breast screening should be annual from the age of forty.

General. Mothers are encouraged to breast-feed children for the protection it offers against mammary malignancy. (Am.J. Obstet. Gyn. 15/9/1984. 150.)

Avoidance of stress situations by singing, playing an instrument. Adopt relaxation techniques, spiritual healing and purposeful meditation to arouse the immune system; intensive visualisation. Avoid the carcinogens: smoking, alcohol.

Information. Breast Cancer Care. Free Help Line. UK Telephone: 0500 245345. ... cancer - breast

Ileus, Paralytic

A failure, usually temporary, of the normal contractility of the muscles of the intestine. Paralytic ileus commonly follows abdominal surgery and may also be induced by severe abdominal injury, peritonitis, internal bleeding, acute pancreatitis, or interference with the blood or nerve supply to the intestine. Symptoms include a swollen abdomen, vomiting, and failure to pass faeces. The condition is treated by resting the intestine. A tube passed through the nose or mouth into the stomach or intestine removes accumulated fluids and keeps the stomach empty. Body fluid levels are maintained by intravenous infusion (drip).... ileus, paralytic

Mouth, Dry

The result of inadequate production of saliva. Dry mouth is usually a temporary condition caused by fear, infection of a salivary gland, or the action of anticholinergic drugs.

Rarely, permanent dry mouth may occur as part of Sjögren’s syndrome or from radiotherapy to treat mouth cancer.

Dryness usually causes difficulty in swallowing and speaking, interference with taste, and tooth decay (see caries, dental).

It may be relieved by spraying the inside of the mouth with artificial saliva.... mouth, dry

Cryptorchidism

An undescended testis (see TESTICLE). The testes normally descend into the scrotum during the seventh month of gestation; until then, the testis is an abdominal organ. If the testes do not descend before the ?rst year of life, they usually remain undescended until puberty – and even then, descent is not achieved in some instances. Fertility is impaired when one testis is affected and is usually absent in the bilateral cases. The incidence of undescended testis in full-term children at birth is 3·5 per cent, falling to less than 2 per cent at one month and 0·7 per cent at one year. Because of the high risk of infertility, undescended testes should be brought down as early as possible and at the latest by the age of two. Sometimes medical treatment with HUMAN CHORIONIC GONADOTROPHIN is helpful but frequently surgical interference is necessary. This is the operation of orchidopexy.... cryptorchidism

Diarrhoea

Diarrhoea or looseness of the bowels is increased frequency, ?uidity or volume of bowel movements compared to usual. Most people have occasional attacks of acute diarrhoea, usually caused by contaminated food or water or excessive alcohol consumption. Such attacks normally clear up within a day or two, whether or not they are treated. Chronic diarrhoea, on the other hand, may be the result of a serious intestinal disorder or of more general disease.

The commonest cause of acute diarrhoea is food poisoning, the organisms involved usually being STAPHYLOCOCCUS, CLOSTRIDIUM bacteria, salmonella, E. coli O157 (see ESCHERICHIA), CAMPYLOBACTER, cryptosporidium, and Norwalk virus. A person may also acquire infective diarrhoea as a result of droplet infections from adenoviruses or echoviruses. Interference with the bacterial ?ora of the intestine may cause acute diarrhoea: this often happens to someone who travels to another country and acquires unfamiliar intestinal bacteria. Other infections include bacillary dysentery, typhoid fever and paratyphoid fevers (see ENTERIC FEVER). Drug toxicity, food allergy, food intolerance and anxiety may also cause acute diarrhoea, and habitual constipation may result in attacks of diarrhoea.

Treatment of diarrhoea in adults depends on the cause. The water and salts (see ELECTROLYTES) lost during a severe attack must be replaced to prevent dehydration. Ready-prepared mixtures of salts can be bought from a pharmacist. Antidiarrhoeal drugs such as codeine phosphate or loperamide should be used in infectious diarrhoea only if the symptoms are disabling. Antibacterial drugs may be used under medical direction. Persistent diarrhoea – longer than a week – or blood-stained diarrhoea must be investigated under medical supervision.

Diarrhoea in infants can be such a serious condition that it requires separate consideration. One of its features is that it is usually accompanied by vomiting; the result can be rapid dehydration as infants have relatively high ?uid requirements. Mostly it is causd by acute gastroenteritis caused by various viruses, most commonly ROTAVIRUSES, but also by many bacteria. In the developed world most children recover rapidly, but diarrhoea is the single greatest cause of infant mortality worldwide. The younger the infant, the higher the mortality rate.

Diarrhoea is much more rare in breast-fed babies, and when it does occur it is usually less severe. The environment of the infant is also important: the condition is highly infectious and, if a case occurs in a maternity home or a children’s hospital, it tends to spread quickly. This is why doctors prefer to treat such children at home but if hospital admission is essential, isolation and infection-control procedures are necessary.

Treatment An infant with diarrhoea should not be fed milk (unless breast-fed, when this should continue) but should be given an electrolyte mixture, available from pharmacists or on prescription, to replace lost water and salts. If the diarrhoea improves within 24 hours, milk can gradually be reintroduced. If diarrhoea continues beyond 36–48 hours, a doctor should be consulted. Any signs of dehydration require urgent medical attention; such signs include drowsiness, lack of response, loose skin, persistent crying, glazed eyes and a dry mouth and tongue.... diarrhoea

Haemorrhoids

Haemorrhoids, or piles, are varicose (swollen) veins in the lining of the ANUS. They are very common, affecting nearly half of the UK population at some time in their lives, with men having them more often and for a longer time.

Varieties Haemorrhoids are classi?ed into ?rst-, second- and third-degree, depending on how far they prolapse through the anal canal. First-degree ones do not protrude; second-degree piles protrude during defaecation; third-degree ones are trapped outside the anal margin, although they can be pushed back. Most haemorrhoids can be described as internal, since they are covered with glandular mucosa, but some large, long-term ones develop a covering of skin. Piles are usually found at the three, seven and eleven o’clock sites when viewed with the patient on his or her back.

Causes The veins in the anus tend to become distended because they have no valves; because they form the lowest part of the PORTAL SYSTEM and are apt to become over?lled when there is the least interference with the circulation through the portal vein; and partly because the muscular arrangements for keeping the rectum closed interfere with the circulation through the haemorrhoidal veins. An absence of ?bre from western diets is probably the most important cause. The result is that people often strain to defaecate hard stools, thus raising intra-abdominal pressure which slows the rate of venous return and engorges the network of veins in the anal mucosa. Pregnancy is an important contributory factor in women developing haemorrhoids. In some people, haemorrhoids are a symptom of disease higher up in the portal system, causing interference with the circulation. They are common in heart disease, liver complaints such as cirrhosis or congestion, and any disease affecting the bowels.

Symptoms Piles cause itching, pain and often bleeding, which may occur whenever the patient defaecates or only sometimes. The piles may prolapse permanently or intermittently. The patient may complain of aching discomfort which, with the pain, may be worsened.

Treatment Prevention is important; a high-?bre diet will help in this, and is also necessary after piles have developed. Patients should not spend a long time straining on the lavatory. Itching can be lessened if the PERINEUM is properly washed, dried and powdered. Prolapsed piles can be replaced with the ?nger. Local anaesthetic and steroid ointments can help to relieve symptoms when they are relatively mild, but do not remedy the underlying disorder. If conservative measures fail, then surgery may be required. Piles may be injected, stretched or excised according to the patient’s particular circumstances.

Where haemorrhoids are secondary to another disorder, such as cancer of the rectum or colon, the underlying condition must be treated – hence the importance of medical advice if piles persist.... haemorrhoids

Liver, Diseases Of

The LIVER may be extensively diseased without any obviously serious symptoms, unless the circulation through it is impeded, the out?ow of BILE checked, or neighbouring organs implicated. JAUNDICE is a symptom of several liver disorders, and is discussed under its separate heading. ASCITES, which may be caused by interference with the circulation through the portal vein of the liver, as well as by other reasons, is also considered separately. The presence of gallstones is a complication of some diseases connected with the liver, and is treated under GALLBLADDER, DISEASES OF. For hydatid cyst of the liver, see TAENIASIS. Liver diseases in a tropical environment are dealt with later in this section.

In?ammation of the liver, or HEPATITIS, may occur as part of a generalised infection or may be a localised condition. Infectious hepatitis, which is the result of infection with a virus, is one of the most common forms. Many di?erent viruses can cause hepatitis, including that responsible for glandular fever (see MONONUCLEOSIS). Certain spirochaetes may also be the cause, particularly that responsible for LEPTOSPIROSIS, as can many drugs. Hepatitis may also occur if there is obstruction of the BILE DUCT, as by a gall-stone.

Cirrhosis of the liver A disorder caused by chronic damage to liver cells. The liver develops areas of ?brosis or scarring; in response, the remaining normal liver cells increase and form regeneration nodules. Those islands of normality, however, suffer from inadequate blood supply, thus adversely affecting liver function. Alcohol is the most common cause of cirrhosis in the United Kingdom and the USA, and the incidence of the disorder among women in the UK has recently risen sharply as a consequence of greater consumption of alcohol by young women in the latter decades of the 20th century. In Africa and many parts of Asia, infection with hepatitis B virus is a common cause. Certain drugs – for example, PARACETAMOL – may damage the liver if taken in excess. Unusual causes of cirrhosis include defects of the bile ducts, HAEMOCHROMATOSIS (raised iron absorption from the gut), CYSTIC FIBROSIS, cardiac cirrhosis (the result of heart failure causing circulatory congestion in the liver), and WILSON’S DISEASE (raised copper absorption).

Symptoms Some people with cirrhosis have no signs or symptoms and the disease may be diagnosed at a routine medical examination. Others may develop jaundice, OEDEMA (including ascites – ?uid in the abdomen), fever, confusion, HAEMATEMESIS (vomiting blood), loss of appetite and lethargy. On examination, cirrhotic patients often have an enlarged liver and/ or SPLEEN, and HYPERTENSION. Liver function tests, cholangiography (X-ray examination of the bile ducts) and biopsy of liver tissue will help to reach a diagnosis.

Treatment Nothing can be done to repair a cirrhosed organ, but the cause, if known, must be removed and further advance of the process thus prevented. In the case of the liver, a high-protein, high-carbohydrate, low-fat diet is given, supplemented by liver extract and vitamins B and K. The consumption of alcohol should be banned. In patients with liver failure and a poor prognosis, liver TRANSPLANTATION is worthwhile but only after careful consideration.

Abscess of the liver When an ABSCESS develops in the liver, it is usually a result of amoebic DYSENTERY, appearing sometimes late in the disease – even after the diarrhoea is cured (see below). It may also follow upon in?ammation of the liver due to other causes. In the case of an amoebic abscess, treatment consists of oral metronidazole.

Acute hepatic necrosis is a destructive and often fatal disease of the liver which is very rare. It may be due to chemical poisons, such as carbontetrachloride, chloroform, phosphorus and industrial solvents derived from benzene. It may also be the cause of death in cases of poisoning with fungi. Very occasionally, it may be a complication of acute infectious hepatitis.

Cancer of the liver is not uncommon, although it is rare for the disease to begin in the liver – the involvement of this organ being usually secondary to disease situated somewhere in the stomach or bowels. Cancer originating in the liver is more common in Asia and Africa. It usually arises in a ?brotic (or cirrhotic) liver and in carriers of the hepatitis B virus. There is great emaciation, which increases as the disease progresses. The liver is much enlarged, and its margin and surface are rough, being studded with hard cancer masses of varying size, which can often be felt through the abdominal wall. Pain may be present. Jaundice and oedema often appear.... liver, diseases of

Memory

The capacity to remember. It is a complex process and probably occurs in many areas of the BRAIN including the LIMBIC SYSTEM and the temporal lobes. There are three main steps: registration, storage, and recall.

During registration, information from the sense organs and the cerebral cortex is put into codes for storage in the short-term memory system. The codes are usually acoustic (based on the sounds and words that would be used to describe the information) but may use any of the ?ve senses. This system can take only a few chunks of information at a time: for example, only about seven longish numbers can be retained and recalled at once – the next new number displaces an earlier one that is then forgotten. And if a subject is asked to describe a person just met, he or she will recall only seven or so facts about that person. This depends on attention span and can be improved by concentration and rehearsal – for example, by reciting the list of things that must be remembered.

Material needing storage for several minutes stays in the short-term memory. More valuable information goes to the long-term memory where it can be kept for any period from a few minutes to a lifetime. Storage is more reliable if the information is in meaningful codes – it is much easier to remember people’s names if their faces and personalities are memorable too. Using techniques such as mnemonics takes this into account.

The ?nal stage is retrieval. Recognising and recalling the required information involves searching the memory. In the short-term memory, this takes about 40-thousandths of a second per item – a rate that is surprisingly consistent, even in people with disorders such as SCHIZOPHRENIA.

Most kinds of forgetting or AMNESIA occur during retrieval. Benign forgetfulness is usually caused by interference from similar items because the required information was not clearly coded and well organised. Retrieval can be improved by recreating the context in which the information was registered. This is why the police reconstruct scenes of crimes, and why revision for exams is more e?ective if facts are learnt in the form of answers to mock questions.

Loss of memory or amnesia mainly affects long-term memory (information which is stored inde?nitely) rather than short-term memory which is measured in minutes. Short-term memory may, however, be affected by unconsciousness caused by trauma. Drivers involved in an accident may be unable to recall the event or the period leading up to it. The cause of amnesia is disease of or damage to the parts of the brain responsible for memory. Degenerative disorders such as ALZHEIMER’S DISEASE, brain tumours, infections (for example, ENCEPHALITIS), STROKE, SUBARACHNOID HAEMORRHAGE and alcoholism all cause memory loss. Some psychiatric illnesses feature loss of memory and AGEING is usually accompanied by some memory loss, although the age of onset and severity vary greatly.... memory

Multiple Sclerosis (ms)

Multiple sclerosis is a progressive disease of the BRAIN and SPINAL CORD, which, although slow in its onset, in time may produce marked symptoms such as PARALYSIS and tremors (see TREMOR), and may ultimately result in a severely disabled invalid. The disorder consists of hardened patches, from the size of a pin-head to that of a pea or larger, scattered here and there irregularly through the brain and spinal cord. Each patch is made up of a mass of the CONNECTIVE TISSUE (neuroglia), which should be present only in su?cient amount to bind the nerve-cells and ?bres together. In the earliest stage, the insulating sheaths (MYELIN) of the nerve-?bres in the hardened patches break up, are absorbed, and leave the nerve-?bres bare, the connective tissue being later formed between these.

Cause Although this is one of the most common diseases of the central nervous system in Europe – there are around 50,000 affected individuals in Britain alone – the cause is still not known. The disease comes on in young people (onset being rare after the age of 40), apparently without previous illness. The ratio of women-to-men victims is 3:2. It is more common in ?rst and second children than in those later in birth order, and in small rather than big families. There may be a hereditary factor for MS, which could be an autoimmune disorder: the body’s defence system attacks the myelin in the central nervous system as if it were a ‘foreign’ tissue.

Symptoms These depend greatly upon the part of the brain and cord affected by the sclerotic patches. Temporary paralysis of a limb, or of an eye muscle, causing double vision, and tremors upon exertion, ?rst in the affected parts, and later in all parts of the body, are early symptoms. Sti?ness of the lower limbs causing the toes to catch on small irregularities in the ground and trip the person in walking, is often an annoying symptom and one of the ?rst to be noticed. Great activity is shown in the re?ex movements obtained by striking the tendons and by stroking the soles of the feet. The latter re?ex shows a characteristic sign (Babinski sign) in which the great toe bends upwards and the other toes spread apart as the sole is stroked, instead of the toes collectively bending downwards as in the normal person. Tremor of the eye movements (nystagmus) is usually found. Trembling handwriting, interference with the functions of the bladder, giddiness, and a peculiar ‘staccato’ or ‘scanning’ speech are common symptoms at a later stage. Numbness and tingling in the extremities occur commonly, particularly in the early stages of the disease. As the disease progresses, the paralyses, which were transitory at ?rst, now become con?rmed, often with great rigidity in the limbs. In many patients the disease progresses very slowly.

People with multiple sclerosis, and their relatives, can obtain help and guidance from the Multiple Sclerosis Society. Another helpful organisation is the Multiple Sclerosis Resources Centre. Those with sexual or marital problems arising out of the illness can obtain information from SPOD (Association to Aid the Sexual and Personal Relationships of People with a Disability). (See APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELFHELP.)

Treatment is di?cult, because the most that can be done is to lead a life as free from strain as possible, to check the progress of the disease. The use of INTERFERON beta seems to slow the progress of MS and this drug is licensed for use in the UK for patients with relapsing, remitting MS over two years, provided they can walk unaided – a controversial restriction on this (expensive) treatment. CORTICOSTEROIDS may be of help to some patients.

The NATIONAL INSTITUTE FOR CLINICAL EXCELLENCE (NICE) ruled in 2001 that the use of the drugs interferon beta and glatiramer acetate for patients with multiple sclerosis was not cost-e?ective but recommended that the Department of Health, the National Assembly for Wales and the drug manufacturers should consider ways of making the drugs available in a cost-e?ective way. Subsequently the government said that it would consider funding a ‘risk-sharing’ scheme in which supply of drugs to patients would be funded only if treatment trials in individuals with MS showed that they were e?ective.

The Department of Health has asked NICE to assess two CANNABIS derivatives as possible treatments for multiple sclerosis and the relief of post-operative pain. Trials of an under-thetongue spray and a tablet could, if successsful, lead to the two drugs being available around 2005.

It is important to keep the nerves and muscles functioning, and therefore the patient should remain at work as long as he or she is capable of doing it, and in any case should exercise regularly.... multiple sclerosis (ms)

Psychosexual Dysfunction

A disorder in which there is interference with the sexual response for no physical cause.... psychosexual dysfunction

Ptosis

Drooping of the upper eyelid. The condition may be congenital, occur spontaneously, or be due to injury or disease, such as myasthenia gravis. Ptosis is usually due to a weakness of the levator muscle of the upper eyelid or to interference with the nerve supply to the muscle. Severe congenital ptosis is corrected surgically to avoid the development of amblyopia.... ptosis

Voice, Loss Of

Inability to speak normally. Temporary partial loss of voice commonly results from straining of the muscles of the larynx through overuse of the voice or from inflammation of the vocal cords in laryngitis. Persistent or recurrent voice loss may be due to polyps on the vocal cords, thickening of the cords in hypothyroidism, or interference with the nerve supply to the larynx muscles due to cancer of the larynx, thyroid gland, or oesophagus. Total loss of voice is rare and is usually of psychological origin. (See also hoarseness; larynx, disorders of.)... voice, loss of

Necrosis

(mortification) n. the death of some or all of the cells in an organ or tissue, caused by disease, physical or chemical injury, or interference with the blood supply (see gangrene). Caseous necrosis occurs in pulmonary tuberculosis, the lung tissue becoming soft, dry, and cheeselike. Coagulative necrosis – the commonest form of necrosis – occurs in almost all organs (except the brain) and results in a solid mass of dead tissue. Colliquative necrosis occurs in the brain, where the absence of stroma (connective tissue) results in total liquefaction of necrotic tissue. —necrotic adj.... necrosis

Pseudoprolactinoma

n. a mass in the pituitary gland region that is associated with a raised blood prolactin level due to interference of the pituitary stalk (through which the chemical dopamine, the inhibitor of prolactin release, passes from the hypothalamus) rather than to increased prolactin production from a pituitary *prolactinoma.... pseudoprolactinoma

Pacemaker

A cardiac or arti?cial pacemaker is a device that helps a faulty HEART to maintain normal rhythm. It consists of a battery that stimulates the heart by an electric current passed through an insulated wire which is attached either to the surface of the ventricle (epicardial pacemaker) or to the heart lining (endocardial pacemaker). In a normal heart, the regular electrical impulses are initiated by a special area of tissue (sinoatrial node). A cardiac pacemaker is used when a person’s sinoatrial node is malfunctioning or when there is interference with the passage of normal impulses. Some devices send out signals at a ?xed rate; others monitor the rate and, when it falters in any way, stimulate regular contractions. Implantation is carried out under a local anaesthetic, and the lithium batteries can last for several years. People with pacemakers should avoid any source of powerful electromagnetic radiation – radio or radar transmitters or airport security screens. (See also CARDIAC PACEMAKER.)... pacemaker

Reflex Action

One of the simplest forms of activity of the nervous system. (For the mechanism upon which it depends, see NERVOUS SYSTEM; NEURON(E).) Re?ex acts are divided usually into three classes.

Super?cial re?exes comprise the sudden movements which result when the skin is brushed or pricked, such as the movement of the toes that results from stroking the sole of the foot.

Deep re?exes depend upon the state of mild contraction in which muscles are constantly maintained when at rest, and are obtained, as in the case of the knee-jerk (see below), by sharply tapping the tendon of the muscle in question.

Visceral re?exes are those connected with various organs, such as the narrowing of the pupil when a bright light is directed upon the EYE, and the contraction of the URINARY BLADDER when distended by urine.

Faults in these re?exes give valuable evidence as to the presence and site of neurological disorders. Thus, absence of the knee-jerk, when the patellar tendon is tapped, means some interference with the sensory nerve, nerve-cells, or motor nerve upon which the act depends – as, for example, in POLIOMYELITIS, or peripheral NEURITIS; whilst an exaggerated jerk implies that the controlling in?uence exerted by the BRAIN upon this re?ex mechanism has been cut o? – as, for example, by a tumour high up in the SPINAL CORD, or in the disease known as MULTIPLE SCLEROSIS (MS).... reflex action

Sprue

A disease occurring most commonly in patients in or from the tropics, and characterised by diarrhoea with large, fatty stools; ANAEMIA; sore tongue; and weight loss. Its manifestations resemble those of non-tropical sprue, or gluten enteropathy, and COELIAC DISEASE.

Causes Tropical sprue is thought to be due to an inborn error of metabolism, characterised primarily by an inability to absorb fats from the intestines. Its epidemiological pattern suggests that an infection such as DYSENTERY may be the precipitating factor. Subsequently there is interference with the absorption of carbohydrates, vitamins, and minerals, leading to anaemia and HYPOCALCAEMIA.

Symptoms Of gradual or rapid onset, there is initial weakness, soreness of the tongue, dif?culty swallowing, indigestion, diarrhoea and poor appetite. Anaemia is typically macrocytic, and mild HYPOGLYCAEMIA may occur. Untreated, the patient steadily loses weight and, unless appropriate treatment is started early, death may be expected because of exhaustion and some intercurrent infection.

Treatment This consists of bed rest, a high-protein diet (initially skimmed milk), and treatment of the anaemia and any other de?ciencies present. Minimum fat should be given to sufferers, who should also take folic acid and cyanocobalamin for the anaemia; large vitamin-B-complex supplements (such as Marmite®) are helpful. Vitamins A and D, together with calcium supplements, help to raise the concentration of calcium in the blood. A long convalescence is often required, which may lead to marked depression, and patients should be sent home to a temperate climate.

Non-tropical sprue is the result of GLUTEN hypersensitivty and is treated with a gluten-free diet.... sprue

Yellow Fever Vaccine Is Prepared From

chick embryos injected with the living, attenuated strain (17D) of pantropic virus. Only one injection is required, and immunity persists for many years. Re-inoculation, however, is desirable every ten years. (See YELLOW FEVER.)

Haemophilus vaccine (HiB) This vaccine was introduced in the UK in 1994 to deal with the annual incidence of about 1,500 cases and 100 deaths from haemophilus MENINGITIS, SEPTICAEMIA and EPIGLOTTITIS, mostly in pre-school children. It has been remarkably successful when given as part of the primary vaccination programme at two, three and four months of age – reducing the incidence by over 95 per cent. A few cases still occur, either due to other subgroups of the organism for which the vaccine is not designed, or because of inadequate response by the child, possibly related to interference from the newer forms of pertussis vaccine (see above) given at the same time.

Meningococcal C vaccine Used in the UK from 1998, this has dramatically reduced the incidence of meningitis and septicaemia due to this organism. Used as part of the primary programme in early infancy, it does not protect against other types of meningococci.

Varicella vaccine This vaccine, used to protect against varicella (CHICKENPOX) is used in a number of countries including the United States and Japan. It has not been introduced into the UK, largely because of concerns that use in infancy would result in an upsurge in cases in adult life, when the disease may be more severe.

Pneumococcal vaccine The pneumococcus is responsible for severe and sometimes fatal childhood diseases including meningitis and septicaemia, as well as PNEUMONIA and other respiratory infections. Vaccines are available but do not protect against all strains and are reserved for special situations – such as for patients without a SPLEEN or those who are immunode?cient.... yellow fever vaccine is prepared from

Spectral Domain Optical Coherence Tomography

(Fourier domain OCT) a noncontact noninvasive imaging technique that can reveal layers of the retina by looking at the interference patterns of reflected laser light. Automated software is able to outline the retinal nerve-fibre layer with great precision, which is relevant in glaucoma.... spectral domain optical coherence tomography

Vocal Folds

(vocal cords) the two folds of tissue which protrude from the sides of the *larynx to form a narrow slit (glottis) across the air passage (see illustration). Their controlled interference with the expiratory air flow produces audible vibrations that make up speech, song, and all other vocal noises. Alterations in the vocal folds themselves or in their nerve supply by disease interfere with phonation.... vocal folds

Vaccine

The name applied generally to dead or attenuated living infectious material introduced into the body, with the object of increasing its power to resist or to get rid of a disease. (See also IMMUNITY.)

Healthy people are inoculated with vaccine as a protection against a particular disease; this produces ANTIBODIES which will confer immunity against a subsequent attack of the disease. (See IMMUNISATION for programme of immunisation during childhood.)

Vaccines may be divided into two classes: stock vaccines, prepared from micro-organisms known to cause a particular disease and kept in readiness for use against that disease; and autogenous vaccines, prepared from microorganisms which are already in the patient’s body and to which the disease is due. Vaccines intended to protect against the onset of disease are of the former variety.

Autogenous vaccines are prepared by cultivating bacteria found in SPUTUM, URINE and FAECES, and in areas of in?ammation such as BOILS (FURUNCULOSIS). This type of vaccine was introduced by Wright about 1903.

Anthrax vaccine was introduced in 1882 for the protection of sheep and cattle against this disease. A safe and e?ective vaccine for use in human beings has now been evolved. (See ANTHRAX.)

BCG vaccine is used to provide protection against TUBERCULOSIS. (See also separate entry on BCG VACCINE.)

Cholera vaccine was introduced in India about 1894. Two injections are given at an interval of at least a week; this gives a varying degree of immunity for six months. (See CHOLERA.)

Diphtheria vaccine is available in several forms. It is usually given along with tetanus and pertussis vaccine (see below) in what is known as TRIPLE VACCINE. This is given in three doses: the ?rst at the age of two months; the second at three months; and the third at four months, with a booster dose at the age of ?ve years. (See DIPHTHERIA.)

Hay fever vaccine is a vaccine prepared from the pollen of various grasses. It is used in gradually increasing doses for prevention of HAY FEVER in those susceptible to this condition.

In?uenza vaccine A vaccine is now available for protection against INFLUENZA due to the in?uenza viruses A and B. Its use in Britain is customarily based on advice from the health departments according to the type of in?uenza expected in a particular year.

Measles, mumps and rubella (MMR) vaccines are given in combination early in the second year of life. A booster dose may prove necessary, as there is some interference between this vaccine and the most recent form of pertussis vaccine (see below) o?ered to children. Uptake has declined a little because of media reports suggesting a link with AUTISM – for which no reliable medical evidence (and much to the contrary) has been found by investigating epidemiologists. (See also separate entry for each disease, and for MMR VACCINE.)

Pertussis (whooping-cough) vaccine is prepared from Bordetella pertussis, and is usually given along with diphtheria and tetanus in what is known as triple vaccine. (See also WHOOPING-COUGH.)

Plague vaccine was introduced by Ha?kine, and appears to give useful protection, but the duration of protection is relatively short: from two to 20 months. Two injections are given at an interval of four weeks. A reinforcing dose should be given annually to anyone exposed to PLAGUE.

Poliomyelitis vaccine gives a high degree of protection against the disease. This is given in the form of attenuated Sabin vaccine which is taken by mouth – a few drops on a lump of sugar. Reinforcing doses of polio vaccine are recommended on school entry, on leaving school, and on travel abroad to countries where POLIOMYELITIS is ENDEMIC.

Rabies vaccine was introduced by Pasteur in 1885 for administration, during the long incubation period, to people bitten by a mad dog, in order to prevent the disease from developing. (See RABIES.)

Rubella vaccine, usually given with mumps and measles vaccine in one dose – called MMR VACCINE, see also above – now provides protection against RUBELLA (German measles). It also provides immunity for adolescent girls who have not had the disease in childhood and so ensures that they will not acquire the disease during any subsequent pregnancy – thus reducing the number of congenitally abnormal children whose abnormality is the result of their being infected with rubella via their mothers before they were born.

Smallpox vaccine was the ?rst introduced. As a result of the World Health Organisation’s successful smallpox eradication campaign – it declared the disease eradicated in 1980 – there is now no medical justi?cation for smallpox vaccination. Recently, however, there has been increased interest in the subject because of the potential threat from bioterrorism. (See also VACCINATION.)

Tetanus vaccine is given in two forms: (1) In the so-called triple vaccine, combined with diphtheria and pertussis (whooping-cough) vaccine for the routine immunisation of children (see above). (2) By itself to adults who have not been immunised in childhood and who are particularly exposed to the risk of TETANUS, such as soldiers and agricultural workers.

Typhoid vaccine was introduced by Wright and Semple for the protection of troops in the South African War and in India. TAB vaccine, containing Salmonella typhi (the causative organism of typhoid fever – see ENTERIC FEVER) and Salmonella paratyphi A and B (the organisms of paratyphoid fever – see ENTERIC FEVER) has now been replaced by typhoid monovalent vaccine, containing only S. typhi. The change has been made because the monovalent vaccine is less likely to produce painful arms and general malaise, and there is no evidence that the TAB vaccine gave any protection against paratyphoid fever. Two doses are given at an interval of 4–6 weeks, and give protection for 1–3 years.... vaccine

Vertigo

A condition in which the affected person loses the power of balancing him or herself, and has a false sensation as to his or her own movements or those of surrounding objects. The power of balancing depends upon sensations derived partly through the sense of touch, partly from the eyes, but mainly from the semicircular canals of the internal EAR – the vestibular mechanism. In general, vertigo is due to some interference with this vestibular ocular re?ex mechanism or with the centres in the cerebellum and cerebrum (see BRAIN) with which it is connected. Giddiness is often associated with headache, nausea and vomiting.

Causes The simplest cause of vertigo is some mechanical disturbance of the body affecting the ?uid in the internal ear; such as that produced by moving in a swing with the eyes shut, the motion of a boat causing sea-sickness, or a sudden fall. (See also MOTION (TRAVEL) SICKNESS.)

Another common positional variety is benign paroxysmal positional vertigo (BPPV) caused by sudden change in the position of the head; this causes small granular masses in the cupola of the posterior semicircular canal in the inner ear to be displaced. It may subside spontaneously within a few weeks but can recur. Sometimes altering the position of the head so as to facilitate return of the crystals to the cupola will stop the vertigo.

The cause which produces a severe and sudden giddiness is MENIÈRE’S DISEASE, a condition in which there is loss of function of the vestibular mechanism of the inner ear. An acute labyrinthitis – in?ammation of the labyrinth of the ear – may result from viral infection and produce a severe vertigo lasting 2–5 days. Because it often occurs in epidemics it is often called epidemic vertigo. Vertigo is sometimes produced by the removal of wax from the ear, or even by syringing out the ear. (See EAR, DISEASES OF.)

A severe upset in the gastrointestinal tract may cause vertigo. Refractive errors in the eyes, an attack of MIGRAINE, a mild attack of EPILEPSY, and gross diseases of the brain, such as tumours, are other causes acting more directly upon the central nervous system. Finally, giddiness may be due to some disorder of the circulation, for example, reduced blood supply to the brain produced by fainting, or by disease of the heart.

Treatment While the attack lasts, this requires the sufferer to lie down in a darkened, quiet room. SEDATIVES have most in?uence in diminishing giddiness when it is distressing. After the attack is over, the individual should be examined to establish the cause and, if necessary, to be given appropriate treatment.

Vertigo and nausea linked to Menière’s disease – or following surgery on the middle ear – can be hard to treat. HYOSCINE, ANTI HISTAMINE DRUGS and PHENOTHIAZINES – for example, prochlorperazine – are often e?ective in preventing and treating these disorders. Cinnarizine and betahistine have been marketed as e?ective drugs for Menière’s disease; for acute attacks, cyclizine or prochlorperazine given by intramuscular injection or rectally can be of value. Research in America is exploring the use of virtual-reality technology to change subjects’ visual perception of the outside world gradually during several 30-minute sessions, helping them to adjust to the abnormal sensations that occur during an attack. Early results are promising.... vertigo

Hydrotherapy, Colon

 Irrigation of the low bowel.

When elimination of body wastes is held up by a chronically-overloaded bowel general health may suffer. A constipated colon, with accumulations of hard faeces, obstructs peristalsis and loses its ability to evacuate effectively. Toxaemia follows, with gross interference of digestion of food.

As contents putrefy, toxins are re-absorbed, poisoning the blood. Such self-induced disease may lie at the root of sluggish liver function, skin disease, blood pressure, and aches in muscles similating rheumatism.

To clean out a clogged colon, injection of a herbal tea into the rectum not only proves effective but brings about a healthful purgation and release from tension. 2-3oz herb is brought to the boil in 1 gallon water, simmered for one minute, and allowed to cool. The tea is strained when warm and injected.

Enema herbs include: Soapwort, Chamomile, Marshmallow, Catmint, Raspberry leaves, Chickweed. Alternative: 20-30 drops Tincture Myrrh added to boiled water allowed to cool. ... hydrotherapy, colon

Inflammation

“A healing crisis (rise in temperature, etc) is an acute reaction resulting from the ascendance of Nature’s healing forces over disease conditions. Its tendency is towards recovery. It is therefore in conformity with Nature’s constructive principle.” (Catechism of Natural Medicine).

It can be a reaction of tissue to infection, injury, surgery, radiation, chemicals, heat or cold, cancer or auto-immune disease.

Every medical student has to commit to memory four classical symptoms: heat, redness, pain and swelling.

As inflammation is a natural process, its progress should not be hindered by too much interference. Invading micro-organisms are destroyed by antibodies and white blood cells. During the encounter white cells may also be destroyed and expelled from the body in the form of pus. They are assisted in their action by an Anti-inflammatory. Most anti-inflammatories are also antiseptics. An external injury should be washed and treated with one.

Selection of remedies varies according to area and degree of inflammation. When occurring in the colon, it was known as ‘colicon’ by Celsus, Roman physician, in the 1st century. His prescription is as apt today:– Aniseed, Parsley, Pepper, few drops Castor oil and a pinch of powdered Myrrh.

Treatment for inflammation would be appropriate to the disease or condition, i.e. inflammation of the inner lining of the heart requires specific treatment as appears in entry for ENDOCARDITIS. For simple external inflammation, a tea of Chickweed, Comfrey or Marshmallow root may be indicated. See: ANTI- INFLAMMATORIES.

Treatment by or in liaison with a general medical practitioner. ... inflammation

Lipoma

A benign tumour of fat, more unsightly that harmful. May be multiple. Rounded, with well- defined border. May grow large, giving rise to symptoms by pressure and interference with function.

Dr Compton Burnett regarded Thuja as the remedy for fatty tissues which he believed to be sycotic by nature.

Alternatives. Liquid Extract Thuja: 5 drops in water, 3 times daily.

Formula: Liquid Extracts: American Bearsfoot half an ounce, Bayberry 1oz, Barberry 60 drops, Syrup Marshmallow 2oz, water to 8oz. Dose: two teaspoons after meals. (Arthur Barker, FNIMH)

Topical. Wipe area with Liquid Extract Thuja 2-3 times daily. Surgical excision usually successful. ... lipoma

Autism

A rare condition in which a child is unable to relate to people and situations. Autism is more common in boys. It is by definition evident before the age of 30 months and is usually apparent in the 1st year of life. The precise causes of autism are unknown. Often, autistic children seem normal for the 1st few months of life before becoming increasingly unresponsive to parents or other stimuli. Extreme resistance to change of any kind is an important feature. The child reacts with distress to alteration in routine or interference with activities. Rituals develop in play, and there is often attachment to unusual objects or obsession with one particular idea. Delay in speaking is common and most autistic children have a low IQ. Behavioural abnormalities may include rocking, selfinjury, screaming fits, and hyperactivity. Despite these symptoms, appearance and muscular coordination are normal. Some autistic people have an isolated special skill, such as an outstanding rote memory or musical ability.

There is no effective treatment for autism, which is lifelong. Special schooling, support and counselling for families, and sometimes behaviour therapy can be helpful. Medication is useful only for specific problems, such as hyperactivity. The majority of autistic people need special, sometimes institutional, care.... autism

Birth Defects

Abnormalities that are obvious at birth or detectable early in infancy. Also called congenital defects, they encompass both minor abnormalities, such as birthmarks, and serious disorders such as spina bifida.

Causes include chromosomal abnormalities, genetic defects, drugs taken during pregnancy, exposure to radiation, and infections. In some cases, the cause of a defect is unknown. Defects that are due to chromosomal abnormalities include Down’s syndrome. Some defects, such as achondroplasia and albinism, are usually inherited from 1 or both parents (see gene; genetic disorders). Certain drugs and chemicals (called teratogens) can damage the fetus if the mother takes or is exposed to them during early pregnancy. Teratogenic drugs include thalidomide (now rarely prescribed) and isotretinoin, which is used in the treatment of severe acne. Alcohol can affect the development of the brain and face (see fetal alcohol syndrome).

Irradiation of the embryo in early pregnancy can cause abnormalities. Very small doses of radiation increase the child’s risk of developing leukaemia later in life (see radiation hazards).

Certain illnesses, such as rubella (German measles) and toxoplasmosis, can cause birth defects if they are contracted during pregnancy.

Brain and spinal cord abnormalities, such as spina bifida and hydrocephalus, and congenital heart disorders (see heart disease, congenital) result from interference with the development of particular groups of cells. Other common defects include cleft lip and palate.

Ultrasound scanning and blood tests during pregnancy can identify women at high risk of having a baby with a birth defect. Further tests such as chorionic villus sampling, amniocentesis, or fetoscopy may then be carried out.... birth defects

Microscope

An instrument for producing a magnified image of a small object. Microscopes are used to examine the structure and chemical composition of cells and tissues, and to investigate microorganisms and diseased tissues. In the operating theatre, microscopes are used in microsurgery.

Compound microscopes are the most widely used type. They have 2 lens systems (the objective and the eyepiece), mounted at opposite ends of a tube called the body tube. There is a stage to hold the specimen, a light source, and an optical condenser which concentrates the light. The maximum magnification is about 1,500 times.

Phase-contrast and interference microscopes are modified light microscopes that allow unstained transparent specimens to be seen. They are used for examining living cells and tissues.

Fluorescence microscopes use ultraviolet light to study specimens stained with fluorescent dyes.Electron microscopes give much higher magnifications than light microscopes by using a beam of electrons instead of light. There are 2 types: transmission electron microscopes (TEMs) and scanning electron microscopes (SEMs). TEMs can magnify up to about 5,000,000 times, enabling tiny viruses and molecules to be seen. SEMs have a lower maximum magnification (100,000 times), but produce 3-dimensional images. This makes them useful for studying surface structures of cells and tissues.... microscope

Numbness

Loss of sensation in part of the body caused by interference with the passage of impulses along sensory nerves. Numbness may be the result of a disorder of or damage to the nervous system or its blood supply.

Multiple sclerosis can cause loss of sensation in any part of the body through damage to nerve pathways in the central nervous system (CNS). In a neuropathy, the peripheral nerves (nerves outside the CNS) are damaged. In a stroke, pressure on, or reduced blood supply to, nerve pathways in the brain often causes loss of feeling on one side of the body.

Severe cold causes numbness by direct action on the nerves. Numbness may also be a feature of psychological disorders, such as anxiety, panic attack, or a hysterical conversion disorder.

Treatment of numbness depends on the underlying cause.... numbness

Stress

Any interference that disturbs a person’s mental and physical well-being. Stress may be experienced in response to a range of physical and emotional stimuli. When faced with stressful situations, the body responds by increasing production of the hormones adrenaline (epinephrine) and cortisol, which produce changes in heart-rate, blood pressure, and metabolism to improve performance. However, at a certain level, they disrupt a person’s ability to cope.Continued exposure to stress often leads to mental and physical symptoms, such as anxiety and depression, indigestion, palpitations, and muscular aches and pains. Post-traumatic stress disorder is a direct response to a specific stressful event. (See also relaxation techniques.)... stress



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