BIOENERGETICS AND METABOLISM

May 8th, 2009

Summary of main points.

• Bioenergetics is the study of energetic events occurring in living organisms; it covers energy (food) intake and energy expenditure.

• Fat is the most energy dense nutrient, containing more than twice the energy of carbohydrate or protein. Energy expenditure is made up of resting metabolic rate, the thermic effect of food and the energy cost of physical activity.

• Bigger people have a higher metabolic rate mainly because of a greater resting metabolic rate from a higher fat-free mass.

• Even very small females require an energy intake of around 1200kcal per day to maintain energy balance.

The living cells of the human body are in a constant state of molecular activity, where they are used, degraded and synthesised to maintain life. These actions require energy which is defined as ‘the capacity to perform work. This definition does not, however, describe the many biological functions that either require or liberate energy in the body.

Understanding what energy is and how the body acquires, converts, stores, and utilises it is the key to understanding how humans can perform activities. It also provides the basis for understanding how fat is used as an energy source, or substrate, and how this may be optimised for best maintenance of body fat levels. The study of energetic events occurring in living organisms, which commenced in the 18th century, is called bioenergetics.

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BABY AND CHILDHOOD DIGESTIVE SYSTEM DISORDERS: WORMS

May 8th, 2009

There are all kinds of worms. Some you find when digging in the garden. They’re usually long, juicy-looking, slimey things but they are useful (so my gardening friends remind me) for aerating the ground and helping plants grow. Then there are cut-worms which always seemed to chop off my new seedlings at ground level (that’s why I gave up gardening). My older brother, an inveterate and fanatical fisherman in his spare time, often searches the beach for worms when holidaying. He says they make good bait.

But I’m getting carried away… I wish to talk about human worms, or rather worms that inhabit the human system. They are commonly called threadworms, or Enterobius vermicularis if you like scientific names you can hardly get your tongue around. They are called threadworms because they look just like that. A bit of white cotton cut up into little lengths. Only they are very active and can turn and twist and crawl around in a most active way.

Worm infestations are common in children. Often the worms, in large numbers, come from the anal canal and crawl around the external part of the back passage. In fact, if examined at night with a torch, many of these creepy crawling things may be seen in a child with a heavy infestation. Personally, they give me the creeps.

In turn, this produces irritation and itching of the back passage. Often the child scratches, and the area may become sore or even infected if the skin is broken and germs start multiplying. Worms are commonly blamed for irritation, nail biting, nervousness and restlessness, especially during the night. Often vague gastric and nerve symptoms are related to infestations, rightfully or wrongfully. And the worms in their merry-making may become lost; cases have been reported in girls where the worms have reached the vagina and set up irritations there. They are also blamed for some cases of ongoing bed-wetting in children. But often there are few or no symptoms.

Commonly all of the children in a family may be infected. The eggs are highly infectious, and transmitted by scratching fingers from the anal region, they may reach toys, school books, writing implements and other objects that are of common interest. Once the eggs have reached the fingers, it is only a matter of time before they reach the mouth, then the bowel. Here they readily and rapidly hatch out, to set up further infestation. Inattention to adequate hygiene is a major factor in their spread. Inadequate hand washing after handling another person’s property, or before handling food or putting the hands to the mouth, is an important factor.

Treatment

Often it is simple to make the diagnosis, and often parents themselves will see the worms in their children. A simple examination of the stools will often reveal their presence; sometimes the doctor will have an examination carried out to discover either the worms or their eggs. These may be collected from fresh stools, or from around the anal margin. A simple test to detect their presence is done by sticking a piece of cellophane adhesive against the patient’s skin, removing it and replacing it on a glass slide which is then examined under the microscope. The doctor or pathologist may do this.

General hygiene is important. All members of the household should be treated at the same time—or the whole class if the disorder is widespread and has come to the general attention of the teachers.

The hand-washing routine after attending the toilet every time, and before handling or eating food, is essential. Soap and hot water should be used. The fingernails should be scrubbed often with a nail brush and soap. Nails should be kept short at all times, and regularly retrimmed. Regular washing of underclothing and bedclothes is important in getting rid of eggs.

Medication is usually very effective. However, although a single dose is often adequate to kill the organism in the bowel, reinfection is common. Ideally, the whole family is treated at the same time, and proper medical supervision is suggested. Pyrantel embonate (commercially known as Combantrin) and viprynium embonate (Vanquin) have been widely and successfully used for several years. Mebendazole (Vermox) in one single dose is also extremely effective.

Roundworms

Infestation by roundworms (Ascaris lumbricordes) is rare in this country. It is common in tropical countries, and may cause abdominal distention, colic, diarrhoea and emaciation. It is diagnosed when the worm or its eggs are located in stools. The egg may be passed in the faeces into the soil, where larvae develop, and are retransmitted to humans via soil-contaminated fingers or feet. Medical treatment is satisfactory.

Tapeworms

Tapeworms (caused by Taenia saginata from beef or Taenia solium from pork) come through eating inadequately cooked infected meat. General abdominal symptoms, diarrhoea and fever may occur. The parasite sucks blood from the bowel lining. Diagnosis is made when parts of the body are detected in faeces. Medical treatment effects a cure.

Giardiasis

A parasitic bowel infestation, giardiasis has been around for many years, but only for a short time, to any appreciable extent, in Australia. It produces loose bowel actions that do not stop within a few days, as do most bowel upsets. Motions are loose, watery, frothy, offensive. Most doctors consider a diarrhoea that has been persisting for a week or more to be most likely caused by this parasite. It is treated with metronidazole, and proper medical supervision is advisable. Treatment is invariably effective, but recurrences may occur. Most cases have been imported into Australia from European and Eastern lands, and it is now firmly entrenched in this country, especially in the eastern states.

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BOTTLE FEEDING

May 8th, 2009

‘Over the years millions and millions of babies have been successfully bottle fed and have come to no harm. If this kind of feeding is necessary, the mother should accept the fact and not have “hang-ups” over it, for the baby will certainly thrive and develop into a happy and healthy child and adult.

‘When bottle feeding the ideal is to hold the baby as close to your body as possible, for close body contact, once more, increases the mother-baby bond which we believe is important to normal development.

‘Is cow’s milk given straight?’ Karen asked.

‘No, cow’s milk must be modified to make it suitable for the baby. Many excellent commercial brands are available which have been modified to simulate mother’s milk as much as possible. Often the proper amount of vitamins and minerals have been added to provide the necessary requirements.

‘Once more, demand feeding may be practised. But, it has been found that overweight is more common in bottle-fed babies. Whereas a baby will automatically gauge how much breast milk he or she takes, a vigilant parent may think it essential that the baby drain the last dregs from a measured amount of fluid in a bottle. Often the baby is best barometer of food needs.’

‘We often hear horrible stories about breast feeding. Some claim it will ruin your figure; your breasts will look terrible afterwards; that you develop fat on the hips and thighs and around the tummy, and so on. What do you say about this?’

‘The breasts certainly increase in size before the birth and during lactation,’ I said. ‘This is inevitable. After it is all over, the breasts tend to return to their previous size. Sometimes, there is a change in the fat distribution of the mother’s body, possibly because of the various hormonal changes that took place during the whole experience. Many women find breast dimensions similar to the time before they were pregnant. Others find them smaller as the fat deposits have lessened.

‘Many women put on from three to six kilograms (6-14 lb) in weight, from the time before pregnancy to the time the baby is a few months old. What’s more, this weight is often hard to dislodge. It tends to accumulate around the hips, thighs and buttocks and abdominal wall. It is often a consequence of the woman’s eating more during these months, perhaps in the hope of producing enough good-quality milk for the baby. But, commonsense eating habits and a sensible diet after it is all over will help her regain her normal pre-pregnancy shape again.’

‘Normally my breasts are quite small,’ Karen said. ‘They are large right now, but will this affect my milk-producing ability?’

‘No, breast size is no indication of how good your supply of milk will be. Often women with small breasts prove to be the most prolific milk producers, whereas many large-busted women are the opposite. Large breasts simply mean they contain more fat, and this has nothing to do with the milk glands and milk production. Aren’t you lucky?’

“What about taking medicines during breast feeding? Is this safe?’

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MINERALS

April 29th, 2009

Sources of minerals and trace elements and their uses

Calcium

function in body: Growth and maintenance of healthy teeth and bones; nerve function; blood clotting; muscle contraction; metabolises iron.

sources: Fish (especially those eaten with bones); soybeans; dairy products; almonds; sesame seeds; sunflower seeds; watercress; fortified cereals. Vitamin D facilitates uptake. effects of deficiency or excess: Deficiency can cause rickets, osteomalacia, osteoporosis.

Chromium (trace element)

function in body: Functioning of skeletal muscles; storing and metabolising sugars and fats.

sources: Unrefined wholegrain and cereal products; fish and shellfish; brewers yeast; beef.

effects of deficiency or excess: Deficiency can cause depression, confusion, irritability. Excess can be toxic.

Cobalt (trace element)

function in body: Component of Vitamin B12 which prevents anaemia.

sources: Meat; liver; kidney; shellfish; green leafy vegetables. effects of deficiency or excess: Deficiency causes lack of Vitamin B12, leading to pernicious anaemia; bowel disorders; weak muscles.

Copper (trace element)

function in body: Formation of red blood cells; growth of bones; absorption of iron; pigmentation of hair and skin. sources: Shellfish; nuts; liver; kidney; pulses; brewers yeast; tap water from copper pipes.

effects of deficiency or excess: Deficiency can cause anaemia, low white blood cell count. Excess can be toxic.

Fluorine (trace element)

function in body: Strengthens teeth and bones.

sources: Fluoridated tap water and toothpastes; fish (especially

those eaten with bones); meat; tea; cereals.

effects of deficiency or excess: Deficiency causes tooth decay,

osteoporosis. Excess causes mottled and discoloured teeth,

increased density of bones in the spine, pelvis and limbs and

calcified ligaments.

Iodine (trace element)

function in body: Production of hormones in the thyroid gland which control metabolism; promotes growth; promotes energy; mental alertness

sources: Iodised salt; Irish moss; kelp; seafood; fruit and vegetables grown in soils containing iodine.

effects of deficiency or excess: Deficiency causes goitre, weight gain, lack of energy. Excess can cause thyroid diseases.

Iron

function in body: Production of haemoglobin; distribution of oxygen and removal of carbon dioxide in body tissues; production of myoglobin (red pigment in muscles). sources: Red meat; liver; kidney; oysters; kelp; pulses; dried fruits; nuts; oats.

effects of deficiency or excess: Deficiency causes anaemia. Magnesium

function in body: Healthy teeth and bones; functioning of the nerves, muscles and metabolic enzymes. sources: Wholewheat cereals and products; eggs; meat; nuts; pulses; seeds.

effects of deficiency or excess: Deficiency causes muscle cramps, tremors, tics, loss of appetite, nausea, insomnia, irregular heart beat.

Manganese (trace element)

function in body: Functioning of the nerves, muscles and many enzymes; bone strength.

sources: Whole grains; nuts; pulses; avocado; egg yolk; green leafy vegetables.

effects of deficiency or excess: Deficiency can cause bone deformities and impede growth rate.

Molybdenum (trace element)

function in body: Metabolism of iron; male sexual function; prevention of dental caries

sources: Oats; barley; pulses; root vegetables; liver.

effects of deficiency or excess: Excess can prevent body from

utilising copper.

Phosphorus

function in body: Conversion and storage of energy; healthy bones; function of muscles, nerves and some enzymes; intestinal absorption of certain foods.

sources: Meat; poultry; fish and shellfish; nuts; seeds; pulses; dairy products; eggs.

effects of deficiency or excess: Deficiency causes bone pain; stiff joints; disorders of the central nervous system; weakness. Excess can interfere with intestinal absorption of calcium, iron, magnesium and zinc.

Potassium

function in body: Maintains balance of fluids and pH in the body; disposal of body wastes; aids in sending oxygen to the brain; function of nerves and muscles.

sources: Fresh fruits and vegetables; whole grains and products; prunes; milk.

effects of deficiency or excess: Deficiency can case muscular weakness and paralysis, low blood pressure; thirst; loss of appetite; sensitivity to noise. Excess can aggravate some heart conditions.

Selenium (trace element)

function in body: Functioning of the red and white blood cells; along with Vitamin E works as an anti-oxidant; detoxifies metals including cadmium, mercury and lead; may protect against some cancers; prevents dandruff and some skin disorders; healthy liver function.

sources: Garlic; onions; whole wheat and products; fish and shellfish; red meat; chicken; broccoli; brewer’s yeast; Brazil nuts.

effects of deficiency or excess: Deficiency causes premature aging, cardiovascular disease and asthma and may be a factor in cancer. Excess can cause neurological disorders.

Sodium

function in body: Along with potassium maintains balance of fluids, especially water, and pH in the body; function of nerves and muscles.

sources: Common salt, baking powder; cured and smoked fish and meats; kelp; beets; artichokes; coconut; figs. effects of deficiency or excess: Deficiency can cause heat prostration, dehydration, low blood pressure and indigestion. Excess causes high blood pressure, heart disorders and oedema (fluid retention).

Sulphur (trace element)

function in body: Synthesis of protein; promotes healthy skin, hair and nails; combats bacterial infection. sources: Meat; fish; dairy poducts; eggs; pulses; cabbage. effects of deficiency or excess: Deficiency can cause skin diseases.

Zinc (trace element)

function in body: Formation of insulin in body; release of Vitamin A; healing; healthy reproductive organs; functioning of growth and development enzymes.

sources: Red meat, liver; egg yolks; dairy products; whole wheat and products; oysters; brewers yeast.

effects of deficiency or excess: Deficiency can cause infertility, enlarged prostate gland, acne and skin disorders, slow healing of wounds, slow physical, mental and sexual development. Excess can cause nausea, diarrhoea, dizziness and dehydration.

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ANXIETY IN THE MIND: LACK OF CONCENTRATION

April 29th, 2009

Students and those whose occupation requires steady brainwork often find that their anxiety shows itself primarily in lack of concentration. They complain of an inability to study or to give full attention to the problem at hand. This of course is a common symptom at examination time. The student sits gazing at his text without reading, or alternatively he reads the same paragraph time after time without fully comprehending what it is all about. In addition to taking the general measures for the relief of anxiety which I will describe, the student can lead himself to greater self-discipline by setting himself a limited daily programme of study which he must always complete. If he starts with a daily schedule within his capacity, he will find that he can steadily increase the amount of work he can handle as his ability to relax increases. With these aids and the reduction of anxiety by the relaxing mental exercises, the ability to concentrate usually soon returns.

In other cases the same inability to concentrate is noticed in reading a novel, or the daily papers, or even in following the conversation of our friends.

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RELAXATION: THE FIRST STEP TO RELIEF

April 28th, 2009

Have you ever sat in a dentist’s chair, waiting for the drill to descend, and been told, ‘Just relax!’? Or been in a doctor’s surgery waiting for an injection or an examination you knew was going to be painful, and been told, ‘Just relax!’ It sounds so simple ‘Just relax’. And it’s the one thing you can’t do, just like that, especially when you’re tense or anxious or worried. It takes a lot of practice. The exasperating thing is that it’s such good advice. If you can relax, you won’t feel so much pain. Fear makes you tense; tension makes a pain worse; and the worse the pain, the more you are afraid. It’s a vicious circle, as you know if you have suffered from it already. So let’s start breaking it.

Preparations-It’s easier to learn how to relax if you have someone to help you. A fellow sufferer is probably the best because you can help one another. It needs to be someone with patience and the time to spare to check you through each stage until the whole thing has become almost second nature to you.

But don’t give up if you can’t find a helper, or if you live alone and friends and family are far away. It’s perfectly possible to teach yourself how to relax, as you’ll see. It just takes a little bit longer if you’re on your own—you have to check on yourself instead of having a friend do it. That necessitates stopping and often means having to go right back to the very beginning: for example, when rearranging cushions, because in getting up to move the cushions you will have tensed your muscles again. A large mirror helps, too, so you can check on your hands and your face, for example. You’ll learn to relax quicker with a friend—and it’s more fun, too—so I’ve written the chapter with instructions for two people, but I have also included throughout how you can expect to feel as you progressively relax and these are the clues to follow if you’re learning on your own.

The best time to start is immediately you have finished a period. This way you should be quite well prepared for the next one, although I ought to warn you at the outset that it often takes two or three months to learn all you need to know about your body and how to get it to relax. Allow yourself at least an hour and wear comfortable clothes. An old bra or no bra at all, rather than a tight one. An old pair of jeans or trousers rather than a pair of skin-tight pants. No girdle or other restricting article of any kind! You need to be warm and easy in whatever you are wearing. If you wear pins or combs or elastic bands in your hair, take them out before you begin. And if you wear jewellery that is knobbly or chunky, remove that too.

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ALLERGIES: ADAPTATION

April 28th, 2009

I have attempted to explain the concepts of clinical ecology in terms of adaptation to environmental exposures—a framework borrowed from physiology. In biology, when an organism comes into contact with a new element in its environment, it often responds in three stages: first, there tends to be an immediate acute reaction; this may be followed by an adapted stage in which there is a suppression of reactive symptoms; and finally, the organism may become maladapted, and perhaps later, nonadapted to repeated exposures by again presenting immediate, acute symptom responses.

Since new patients usually first come to their physicians midway in this process, they tend to present quite a different clinical picture than observed in laboratory animals. Instead of the sequence noted above, patients are first seen by their physicians as their adaptation to that to which they are susceptible is petering out. To what and for how long they had been adapted to such a frequently repeated exposure, which had maintained a relatively stimulatory phase, remain unknowns. Indeed, such a substance often appears to agree with an adapting person very well. But sooner or later—largely depending on the degree of individual susceptibility—such a person slips into a withdrawal phase for longer and longer periods. In other words, he completes this transition (usually called the onset of the present illness) and is now maladapted (badly adapted).

Such a transition from an adapted and relatively symptom-free existence to chronic illness often involves many side trips, including various levels. The speed with which this transition takes place is also partially dependent on the patient’s awareness of his problem. If he remains totally unaware of the environmental cause(s) of his symptoms, the transition may take place fairly rapidly, If he is aware that eating in general, for instance, agrees with him, he may be able to slow the onset of maladaptation, although he may become progressively obese in the process. And finally, if the patient is aware of the particular food(s) related to his symptoms, he may be able to delay his ultimate downfall by a judicious intake of the particular culprit. Eventually, however, most patients lose their symptom-suppressed adaptation to such substances and wind up in a doctor’s waiting room. Unfortunately, there is another outcome which may occur at any stage of this adaptation process to food(s). Some patients, suspecting that all food and/or food additives and contaminants make them ill, simply stop eating. This may lead to a marked loss of weight and hazardous undernutrition.

For the reader interested in greater detail, adaptation is defined as the ability of an organism to be modified in its function by the impingement of its environment. In the specific and individualized sense employed here, adaptation is limited to observed clinical manifestations resulting from the impingement of given environmental exposures to which individuals are highly susceptible.2,3 Adolph also observed similar effects in animals.4

Environmental features contributing to specific adaptation are the following: a) Given exposures must be cumulative and preferably intermittent. Those substances, such as common foods, retained in the body temporarily are most effective in inducing and maintaining specific adaptation. b) Specific reexposures should be approximately the same size, and rate of absorption through a common portal of entry. c) Given environmental exposures may be harmless (foods) or alleged to be toxic in greater concentrations, although thought to be safe in the lesser amounts encountered (chemicals).

Bodily features contributing to specific adaptation include: ability of an individual to adapt; this probably depends on: a) inherited tendencies, b) adequacy of apparent physiologic mechanisms,5-8 and c) variations in the degree of specific susceptibility, inasmuch as a heightened susceptibility seems to enhance the impact of lesser dosage and accelerates the advancement of the adaptation process.

Because of these environmental and bodily (individual) variants, adaptation to given environmental exposures develops and advances more rapidly in some individuals than in others. For instance, one person may present only a few localized syndromes from only a few environmental exposures, whereas another person may manifest many apparently different physical and more advanced cerebral and behavioral syndromes from multiple exogenous exposures. More over, such lesser and advanced responses may alternate in a given person at different times.9 This alternation of what later were called allergies (rhinitis, asthma, eczema, and headache) with psychoses was apparently first pointed out in 1884 by George Savage, an English psychiatrist. In contrast to this highly individualized interpretation of adaptation to specific environmental exposures, traditionally physiological adaptation has been presented elsewhere in respect to its general features and common bodily mechanisms.5-7 Since a given individual is adapting not only to common foods and lesser chemical exposures, but also to many other environmental stimuli— such as infection, cold, heat, radiation, etc.—the ability to adapt or maladapt must also be considered in a broader context. For instance, it is known that virus infections frequently induce or precipitate maladapted allergic responses to other materials. The same relationship holds for systemic yeast infections,11 and sometimes other infectious processes. Adequate treatment of a concomitant infection in the management of allergies must always be considered. It is also well known that sudden exposure to cold in some persons may be generally deleterious. Although the relationship of these secondary factors in adaptation is important, a detailed discussion of them is beyond the scope of this popular presentation.

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CHOKING IN CHILDHOOD

April 28th, 2009

Choking is one of the few true emergencies of childhood in which minutes may determine life or death. A swallowed object is the most common and serious cause of choking. Choking is caused by the obstruction of the airway resulting in an inability to breathe. It is easily identified by two key signs: the child frantically tries to breathe, and the child is not able to cry out or to speak.

If choking continues, the child quickly becomes blue, convulsive, limp, and unconscious. If the object completely blocks the air passage, you have only a few minutes to reestablish an airway before brain damage or death can occur.

The objects that choke children are usually of a shape and size to plug the opening into the throat like a cork. Frequent and especially dangerous causes of choking are peanuts, tablets, glass eyes of toy animals, hard or hard-coated sweets, beads, popcorn, and tiny toys or small parts from toys. Solid particles of food from the stomach may choke a child who breathes in during vomiting. A vomiting baby is safest from choking when lying on his or her stomach.

Choking may also occur in a child who has croup. But choking caused by croup is slightly different and is treated differently. A child choking from croup frantically tries to breathe, but the child is still able to speak or cry. See the article on Croup for treatment of that form of choking.

Signs and symptoms

Choking on an object is easily identified by the two major symptoms. There are frantic, unsuccessful efforts to breathe. The child cannot talk or cry.

Home care

Seconds count! Scream for help. A second adult on the scene should phone the police or paramedic squad for help. (Police are usually more quickly available in most communities than an ambulance, the fire department, or a doctor.)

First, give your child one minute to clear the obstruction by his or her own efforts. If this doesn’t work, place your child’s head down over a chair, table, or your lap and pound hard on his back four times. Broken ribs heal; death does not. Support the child’s head and neck before pounding to avoid fracturing the neck.

Only if safer measures fail should you consider reaching into the child’s mouth with a hooked finger or tweezer in an effort to remove or dislodge the foreign body: there’s a good chance of pushing the object more tightly into the windpipe in your desperation to remove it. If your child is not breathing after the object is removed, give mouth-to-mouth resuscitation until trained help arrives.

Precautions

• Never give mouth-to-mouth resuscitation until the obstructing object is removed; to do so may force the object further down the throat.

• Prevention of choking is most important. Examine all toys for loose eyes or other small parts. Keep tablets under lock and key. Do not give peanuts, popcorn, or hard sweets to toddlers. (Clean up after adult parties before children can wander unattended into a room.)

Medical treatment

When the object completely blocks the air passage, the child seldom reaches a doctor in time. However, the object may only partially block the airway, even though you may not think so. Your doctor will operate, on the spot, to open the windpipe through the neck (tracheotomy). Then oxygen, artificial respiration, and intravenous fluids will be given.

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MALE FERTILITY TESTS: ‘HAMSTER’ TEST, WHITE BLOOD CELLS AND HORMONE TESTS

April 23rd, 2009

Sperm Penetration Assay or ‘Hamster’ Test

This is a test which uses hamster eggs to see whether the sperm can penetrate the eggs. Human sperm are able to penetrate hamster eggs but they cannot (thankfully!) develop into embryos. For the test the zona pellucida (outer layer) of the hamster eggs is removed and the doctors observe how many sperm can penetrate each egg. I doubt the value of this test because if the outer layer of the egg has been removed then it does not replicate the situation between a man and woman, where the sperm has to penetrate the outer layer of the egg for fertilisation to take place. It also suggests that you can compare a woman’s egg and a hamster’s egg. This test may result in totally worthless information and also involves the unnecessary use of another animal.

White Blood Cells

Immature sperm appear as round cells in the semen before they develop into their characteristic tadpole-like shape. White blood cells are also round and it is not easy to distinguish the two in a sample so special stains are used. It is important to know whether white blood cells are present because they can cause infertility. They could indicate an infection in the urinary tract. If white blood cells are noticed then further investigations are needed to rule out ordinary bacteria or an infection like Chlamydia.

Hormone Tests

Hormones may be tested and these could include FSH, LH, prolactin, testosterone and thyroid hormones. If FSH levels are high, it may indicate that there is a problem with sperm production in the testes. Giving high doses of testosterone as a medication can actually reduce the sperm count; so we come back once again to the idea of balance, with the hormone needing to be just right, neither too high nor too low. Some medications, such as clomiphene citrate and tamoxifen, have been used to treat male infertility but they are controversial and we do not know how beneficial they are.

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EXTENDING AGE: THE SCIENCE OF LIVING TOGETHER

April 22nd, 2009

Scientific studies have rather consistently demonstrated that companionship contributes to good health. The quality of relationships also is a factor, found Xinhua Steve Ren, Ph.D., assistant professor at the Boston University School of Public Health and research health scientist with the Center for Health Quality, Outcome, and Economic Research of the Veterans Affairs Medical Center in Bedford, Massachusetts. Here are some of his other findings.

•     Separation and divorce can actually improve health – but only in cases where there were serious ongoing marital problems. Separation and divorce are most detrimental to health when the marriage had no prior serious problems and the crisis arose with the sudden discovery of infidelity.

•     Being separated is more injurious to health than divorce. The separated were more than 2 times as likely to consider themselves in poor health than were married folks, while divorced people were about 1.3 times more likely to think themselves in ill health.

•     The quality of a relationship-whether marriage or cohabitation-affects the participants’ health. Those in unhappy relationships are at higher health risk than those who are in happy relationships and, surprisingly, even than those who are divorced.

•     Compared to married people, the unmarried tend to have higher death rates from all causes, have higher levels of stress, and use more health services.

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