Stories tagged medicine

Medical researchers are developing nanorobots to deliver drugs directly where they are needed in the body.

Meanwhile, researchers in California are using bacteria to grow electronic circuits out of nanotubes.

A European study has found that women taking oral contraceptives (birth control pills) are at a higher risk for blood clots and heart disease.

Oct
30
2007

Plasmodium falciparum, the parasite that causes malaria.: Photo courtesy NIH
Plasmodium falciparum, the parasite that causes malaria.: Photo courtesy NIH

Malaria is one of the most deadly diseases in the world. Spread by mosquitoes, each year it kills more than 1 million people, and makes 300 million seriously ill, mostly children, mostly in Africa.

For years researchers have tried to find a vaccine that will prevent people from contracting the disease. The problem is, the parasite enters the bloodstream at a particular phase in its life cycle. Collecting the parasite at that stage is tricky, because it lives in the salivary glands of the mosquito.

But now a research lab in suburban Maryland has figured out a way to collect the parasites. They breed their own highly infectious mosquitoes, which they keep locked behind five doors so none escape. Once the parasite has reached the proper stage, workers kill the mosquitoes and extract the parasite.

After they collect the parasite, they disable it and render it harmless. It can then be injected into a person. The body recognizes the parasite as a foreign body and produces antibodies to fight it. These antibodies stay in the bloodstream, protecting the person from any real parasites they may later pick up.

Early test indicate the vaccine could be up to 90% effective, and protect against malaria for 10 months or more. Human trials are to begin next year.

You can learn more about malaria in The Science Museum’s on-line exhibit.

Oct
16
2007

A denrimer molceule: Image from Wikimedia Commons.
A denrimer molceule: Image from Wikimedia Commons.

New treatments for AIDS and cancer, based on nanoparticles, are about to go into human trials. Both treatments use dendrimers, molecules with multiple arms. Each arm can be designed to do different things. In the case of the AIDS treatment, the arms clasp onto docking sites on the virus’s coating, preventing it from attaching to and infecting healthy cells. In the cancer treatment, some of the arms hold folic acid, which cancer cells absorb; the other arms hold an anti-cancer drug, which is then released inside the cancerous cell.

Dendrimers were invented 30 years ago, but have had few practical applications, since they are difficult and expensive to make. But new processes promise to speed up production, perhaps unlocking the promise of these molecules.

To see images of dendrimers, go here.

Oct
15
2007

A slice of a brain infected with Alzheimer's: The disease shrinks brain tissue and leads to severe memory loss. Photo by AJC1 at Flickr.com
A slice of a brain infected with Alzheimer's: The disease shrinks brain tissue and leads to severe memory loss. Photo by AJC1 at Flickr.com

Researchers at Stanford have developed a blood test which, in early trials, has been 90% accurate in identifying patients with Alzheimer’s disease. The test is also 80% accurate in predicting who will get Alzheimer’s in the next 2 to 6 years.

The article notes:

At present, treatments for Alzheimer's disease are not very effective, so some people might not want early notification that they have an incurable ailment. But other people might want it.

What do you think? If you had an incurable disease that would not start to manifest itself for several years, would you want to know?

Oct
03
2007

What will I do now when you're sick?
What will I do now when you're sick?
If you are the parent of a young child like I am, you are probably bombarded with conflicted information, much like I am.

Don’t give toddlers whole milk! There is too much fat in whole milk for their diets! You must give toddlers whole milk! Their brains need the fat to develop!

And, if you are the parent of a small child, you live though, and often experience first hand, every illness they come across – including what appears to be an honest interest in the world record for number of colds in a 6 month period.

Now information comes out of the Food and Drug Administration (FDA) on over-the-counter (OTC) multisymptom cough and cold medicines for children under 6 that makes life more confusing. Back in August they issued a safety advisory and last Friday safety experts working for the FDA urged the agency to ban all these multisymptom medicines and to standardize the cups, droppers and syringes included with products for children to reduce confusion and the resulting possibility of overdose.

The recommendation comes from a 356-page report in which the FDA’s safety experts reported that there is little evidence that multisymptom cough and cold medicines are effective in young kids, and that they may in fact be dangerous. According the report, over the past 37 years at least 54 children died after taking decongestants, and 69 died after taking antihistamines. A study by the Centers for Disease Control found that more than 1,500 children under the age of 2 had suffered serious health problems after being treated with common cough and cold medicines between 2004 and 2005.

Not surprisingly, the drug companies have an industry trade group called the Consumer Healthcare Products Association, and they issued their own report (only 156 pages) and they recommended adding mandatory warning labels indicating that the drugs not be used in children under 2, but not that they be banned. Currently when you look at the back of these medicines, they tell you to “consult your doctor” for administering to children under two.

The next step in this process is a meeting of outside experts on October 18 & 19 to examine the safety issues and provide recommendations to the FDA.

It is an interesting dilemma for our household as we head into cold season (and as I see all the runny noses this morning at daycare). My doctor recommends using them, as other remedies (saline drops and suction to clear out the nose – not fun and propping up their head while they sleep) don’t seem to help much. And from my perspective, the cold medicinesdo seem to help. What will we do the next time our 18-month old gets sick when my experience is that I can give her something that will make her feel better but that there is a small, but dangerous, chance that in doing so I am putter her at risk? I think I’ll be forced to make a decision about this very soon.

Mar
23
2007

Sick people need drugs.  Drugs cost money.  Is it OK to steal them?: Photo by .ash from flickr.com
Sick people need drugs. Drugs cost money. Is it OK to steal them?: Photo by .ash from flickr.com

Abbott Laboratories, a major drug manufacturer in the US, has announced that it will no longer market drugs in Thailand. The Thai government broke Abbott’s patent on an AIDS drug, allowing other companies to make generic versions.

Some people criticize Abbott, claiming that sick people need the drugs, and human health should come before corporate profits. Others, however, support Abbot, saying that without profits, the company has no incentive to develop much-needed drugs, and no money to do so even if it wanted to.

What do you think? Should drug companies withhold their products from countries where their patents are not honored?

Mar
12
2007

AIDS virus: Image NIH
AIDS virus: Image NIH

A medical research lab at Emory University in Georgia is developing an AIDS vaccine. Animal trials are encouraging – test subjects are developing AIDS antibodies in response to the vaccine.

The vaccine uses some genetic material from the AIDS virus, but not enough to actually get sick. After being exposed to this decoy virus, the body produces antibodies that can block AIDS, and also increases T cells that can kill the virus.
Researchers expect the vaccine could be available in three to four years.

Jan
18
2007

A breast cancer cell: Photo from NIH
A breast cancer cell: Photo from NIH

A researcher at the University of Alberta in Edmonton, Canada has discovered a drug that causes cancer cells to die, without harming healthy cells nearby. The drug, called DCA, changes the way cancer cells get energy and, as a side-effect, kills them.

According to the article:

DCA attacks a unique feature of cancer cells: the fact that they make their energy throughout the main body of the cell, rather than in distinct organelles called mitochondria…. DCA reawakened the mitochondria in cancer cells.

Crucially, though, mitochondria do another job in cells: they activate apoptosis, the process by which abnormal cells self-destruct. When cells switch mitochondria off, they become “immortal”, outliving other cells in the tumour and so becoming dominant. Once reawakened by DCA, mitochondria reactivate apoptosis and order the abnormal cells to die.

But perhaps the best thing about this news is that DCA already exists. It has been used for years to treat other diseases, so we know it’s safe to use on humans. And it is not patented – any company can make it cheaply.

The drug still has to go through rigorous testing to see how effective it really is, and what dosage and procedures work best. But if this pans out, it will be exciting news for cancer patients everywhere.

Meanwhile, the number of deaths from cancer in the US dropped for the second straight year. While cancer remains the #2 killer in America (after heart disease), doctors have seen a drop in both the rate of cancer death (the percentage of cancer patients who die from the disease) and the total number of deaths.

Together, these two items make for some very good news in the fight against cancer.