News for the ‘Skin Care’ Category

SKIN AND COSMETICS: MOISTURIZERS

Moisturizers are mixtures of oil and water which trap water within the skin, making it more pliable, looking and feeling less dry, and smoother and softer. This allows make-up to be applied more evenly. Moisturizers can also plump up the skin, making wrinkles less visible. They do not, however, prevent wrinkles, treat wrinkles, or alter the ageing process. They are analogous to hair conditioners. Moisturizers work in three main ways:
- Moisturizers can have an occlusive action, whereby the surface of the skin is ‘glued’ down, preventing water evaporation. Heavier moisturizing creams provide a thicker glue, which decreases water loss. Thicker preparations include lanolin, petrolatum, paraffin and mineral oils. These products may block the pores, resulting in blackheads, whiteheads and acne but are useful for older people with very dry skin.
- Humectants are substances which draw water from the deeper layers of the skin to the surface. This means that the deeper layers become dehydrated at the expense of the surface. Collagen, elastin, glycerine, propylene, glycol, sorbitol, vitamins A and E and many other proteins act as humectants. However, if the surface of the skin is damaged, all the water escapes and both the top and deeper layers of the skin are left dehydrated.
- Liposomes are little capsules which bind to the surface of the skin and release moisture on to the cell membranes. Although this sounds very fancy, it is really just another way of applying a moisturizer.
Most moisturizers contain both glue-type substances and humectants. They draw water to the surface of the skin and keep it there, making the skin look plumper and smoother. Super-rich moisturizing creams and night creams contain a higher quantity of glue-like substances, and so trap in water for longer periods of time. On the other hand, they are responsible for many blemishes due to their suffocating effect on the skin. Despite all this, moisturizers do not alter the ageing process, nor do they repair the damage caused by excessive sun exposure.
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Edited: April 25th, 2011

SKIN INFECTION: SCABIES

The most common parasitic infestation of man is by the mite Sarcoptes scabei. The mite is less than half a millimetre long, and barely visible to the naked eye. The female is fertilized on the skin surface and then burrows into the skin, depositing eggs on the way. The eggs hatch in four days, the larvae maturing on the surface ten days later. As the life cycle is completed on the skin, the untreated scabies infection will persist indefinitely.

Human scabies has played a modest but not insignificant role in history. Severe infestations have lowered the morale of armies in the field, contributing to major military defeats. The world incidence shows an interesting cyclical pattern which is not completely understood. Scabies is usually transmitted by close personal contact, usually in the warmth of a bed. Indirect spread is relatively rare. The mite cannot survive for more than a few days away from the skin. The connection between promiscuity and scabies is indicated by the very similar age end seasons} incidence of scabies and venereal disease (that is, both occur most commonly in young people in the 16-25 age-group, particularly in the summer months) and the fact that those with scabies are not infrequently found to have venereal disease as well.

The lesions of scabies are mostly a manifestation of allergy to the mite or its products. With a primary infestation symptoms do not appear for weeks after contracting the disease. If, however, a person has been previously affected, he or she will develop spots and itching within hours of contracting the disease. The commonest and most disabling symptom of scabies is an intractable, generalized, unrelenting itch. It is markedly worse at night. Examination of the webs between the fingers, of the wrists, the breast or penis, may reveal the classical burrows where the mite has gained entry. Secondary lesions, however, account for most of what is seen. These consist of various lumps, bumps, pustules, crusts, and scratch marks. Only rarely is the face or neck involved. The areas most commonly involved are the hands, the breasts, the buttocks, and the genitals. Confirmation of infection is by microscopic identification of the mite, its eggs or its droppings. They are usually found in one of the burrows.

Treatment involves the whole family and all intimate contacts. The whole skin below the chin must be treated, not just the areas which appear involved. After a hot bath and scrub, 25 per cent benzyl benzoate emulsion, or 1 per cent gammabenzene hexachloride cream should be applied. Twenty-four hours later, this should be repeated without bathing between times. The clothing and bed linen must then be changed. Normal laundering or hanging up of the clothes for a week will destroy the remaining parasites and larvae. The treatment may if necessary be repeated once after two weeks. Extra applications should be avoided because of the irritant effect of the applications.

Scabies is by no means rare these days. It can be very difficult to diagnose, however, in the well-groomed and well-washed individual who is often. In fact, the sufferer of this complaint.

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Edited: May 8th, 2009