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Archive for July, 2011

TUMOR RECURRENCE AND TAMOXIFEN RESISTANCE: WHAT CAUSES DRUG RESISTANCE?

Posted on July 28, 2011, under Cancer.

Cancer cells develop resistance to specific types of drugs in many ways. Perhaps one of the first steps is exposure of the cells to concentrations of drug that are not high enough to kill them. A patient may have been given a dose of chemotherapy that is too low, or a standard dose may have been administered to a patient who has faster metabolism or excretes drugs more rapidly than the average person. Thus, the cells are exposed to low concentrations of drug without being killed. The resulting cancer cells are now “educated” about how to deal with the drug, so that even if the next dose is higher, the cells have a better chance of fending off its toxic effects. That is why chemotherapy drugs must be given in doses that are high enough to kill the cancer cells but below the level that causes severe side effects.
Once cancer cells have been exposed to a specific drug in concentrations that have not killed it, the cells may develop a number of techniques to handle the drug and keep themselves from being killed. Perhaps the most common mechanism that breast cancer cells adopt is the ability to pump the drug outside the cell (55, 56). This action occurs even in normal cells, where it functions to protect the cells from toxins during everyday life (dietary or environmental toxins, for instance).
Cancer cells have other methods of becoming drug resistant. In the case of methotrexate they actually go through elaborate changes in their biochemistry after exposure to the drug. The cancer cells have the ability to increase the amount of protein that is the target for methotrexate—an enzyme called dihydrofolate reductase. With augmented production of the enzyme, the cells have found a way to protect themselves from the lethal effects of the chemotherapy agent.
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ALTERNATIVES TO HRT: ‘NATURAL’ PROGESTERONE AND OESTROGEN

Posted on July 17, 2011, under Women's Health.

You need to be aware that progesterone creams contain a powerful pharmaceutical hormone that is made in a laboratory. Because the US FDA (Food and Drug Administration) won’t allow the manufacturers of the creams to make medical claims, they are sold as cosmetics, not as hormone replacements. It is because these creams contain a pharmaceutical agent that the UK’s Medicines Control Agency will only let them be sold under prescription, and rightly so. My main concern is that women are being duped into thinking they are buying a natural herbal remedy containing wild yam. They are not: they are buying hormone replacement – just a different hormone (progesterone instead of the usual HRT combination of a form of oestrogen plus progestogen). And they may not be buying anything truly to do with wild yam, which has a very respectable reputation as a herbal treatment for menstrual and menopausal problems. Although for centuries, herbalists have indeed used wild yam in a tincture form, the effect of the herb in its pure state is very different from that of the synthesized progesterone. This wild yam is taken orally and has traditionally been used as an anti-spasmodic and anti-inflammatory herb. As is the case with so many effective herbs it is not known precisely how it acts on the body. Since the essence of herbal medicine is that all the ingredients help towards the overall therapeutic effect, diosgenin alone cannot be responsible for the wild yam’s beneficial qualities. Herbs work because they contain a host of substances – active substances, balancing substances and substances that cope with any side effects of the active substances. They are holistic and truly ‘natural’. But the ‘natural’ progesterone that is being hyped is no more ‘natural’ than a number of the plant-based oestrogen preparations that form the basis of some HRT products.
These oestrogens are ‘natural’ in the same sense that plant-based progesterone is classed as ‘natural’. The oestrogens too are synthesized in the laboratory from soya beans and yams. They still have side effects, however. We need to be clear that these hormones, oestrogen and progesterone, which are synthesized in a laboratory from plants, are not natural to us. They may be chemically identical to what our bodies produce but they are powerful drugs, hence the need to put them on prescription. Plant-based progesterone is termed ‘natural’ because it has the same molecular structure as the progesterone molecule found in humans. This idea of different substances being chemically identical can be very misleading. For example, coal, diamond and graphite (the ‘lead’ in your pencil) are all chemically identical and yet they have very different properties and functions. They have the same molecular structure, but you wouldn’t expect to produce much heat by putting diamonds on the fire.
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REDUCING YOUR RISK OF CORONARY ARTERY DISEASE: TYPES I AND II DIABETES

Posted on July 3, 2011, under Cardio & Blood-Сholesterol.

Type l diabetes often occurs in younger people (it used to be called juvenile-onset diabetes) and affects about 1 million Americans. It is caused by decreased or no insulin production by the pancreas. The high blood levels of glucose (called hyperglycemia: hyper means “high,” give means “sweet,” emia means “in the blood”) must be regulated by insulin injections to compensate for the deficiency of insulin production.
Type II diabetes is much more common than type I diabetes. It is known to affect at least 7 million Americans. Another 5 to 7 million people probably have type II diabetes but are unaware of it. More than 75 percent of people who have type II diabetes are over- weight. Evidently, obesity is a “trigger,” causing diabetes to develop in genetically vulnerable people. For them, the problem is both a deficiency of insulin and an inability of their body’s cells to respond appropriately to the insulin that is there. Evidence is mounting that exercise lowers the risk of type II diabetes developing, even in people who are overweight or who have a family history of diabetes. The best treatment for type II diabetes is weight loss, but if this is not achievable, then oral medications, or insulin injections, may be required.
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