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Scientists' social experiment: putting their DNA data online

From The Mercury News:

If you haven't heard of the PGP-10 yet, you will. No, they are not defendants in some crime of the century. Nor are they a new techno group. If anything, the PGP-10 resemble a chorus line performing what one geneticist calls a Molecular Full Monty.

This cohort of entrepreneurs and scientists is the cutting edge of the Personal Genome Project begun by Harvard Medical School. On Tuesday, in an act of altruism and/or exhibitionism, the PGP-10 put their medical records, traits and genetic codes on the Web where all the scientists, paparazzi and peeping Toms can see them.

The aim is to create a huge public database of information to speed research into the causes and cures for genetic maladies. The leader is geneticist George Church, otherwise known as No. 1 in the PGP-10 list, where you can find out that he has narcolepsy and motion sickness. As you can see, Church believes that privacy is a rather old-fashioned concept. He hopes to eventually get 100,000 people willing to have their DNA snips publicly searched.

The 10 volunteers are part of a long history of scientists who experiment on themselves. Only this is not just a scientific experiment, it's a social experiment. The PGP-10 aren't in danger of untested vaccines or radium. They may, however, be in danger of social stigma.

It's one thing to be part of a vast research project for the common good. But what are the costs of having your genome, let alone your medical records, an open book? Or, rather, an open Web site?

So far, there have been no shocking discoveries in the first 20 percent of the DNA sequences released, although psychologist Steven Pinker (aka No. 8, with a normal prostate and flat feet) did discover a genetic predisposition for "... irregular periods. And this high-profile group is pretty insulated from the dangers that aren't covered in the new federal law forbidding genetic discrimination in employment or health insurance.

But DNA is also a family matter. Sharing your genes is sharing information about your sister, mother, children and unborn grandchildren. We have yet to learn what it will be like to know — and have it known — that we carry a genetic marker for a disease or mental illness.

If you have the genetic predisposition for diabetes, will someone tell you to drop that candy bar? Does losing your glasses take on another meaning if it's known that you have the Alzheimer's gene? There's enough concern for even Pinker to "reserve the right of a line-item veto" for that part of his code.

As life science entrepreneur Stanley Lapidus (aka No. 6 and genetically susceptible to tuberculosis) says, "We are part of a group that will help define what is medical privacy. I'm making a statement. I may regret it." But there are already 5,000 volunteers lined up behind him in the queue. And above all else, they may be proving how attitudes toward privacy itself have already changed.

We now live in a Facebook era. Astonishing numbers of Americans put their lives on the Web. We live with blogs, and video cameras at every ATM and political rally. Off the record ends up on YouTube. What was once private, like depression or sexual dysfunction, is now cocktail chatter. Openness, social networking, crowdsourcing are the new norms. People put their own medical issues on Web sites like in return for shared information.

Meanwhile, more people are getting their DNA "done." As the price goes down, it may become routine. If we require presidential candidates to release their health records and financial records, why not their DNA? And what happens if, as one geneticist fantasizes, we discover a Machiavelli gene? Machiavelli for president?

Posted: 10/30/2008 9:00:00 AM

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Revealed: The saliva test that detects early signs of stroke

From the Daily Mail (U.K.):

A simple saliva test could help doctors identify patients most at risk of a life-threatening stroke.

New research shows that high levels of the hormone cortisol in saliva are directly linked to the build-up of fatty deposits in arteries carrying blood to the brain.

When these deposits - called plaques - break loose, they can cause a blockage that starves the brain of blood and oxygen.

Research published in the Journal of Clinical Endocrinology and Metabolism suggests many strokes could be prevented if doctors routinely tested patients' saliva.

Strokes are the third most common cause of death in England and Wales, after heart disease and cancer. They occur when a clot cuts off the blood supply to the brain.

Clots are often caused by fatty deposits that get dislodged and travel towards the brain. Once they get into smaller blood vessels in the skull, they cause a blockage.

In the latest study, experts at the Erasmus Medical Centre in Rotterdam, Holland, and the Technical University of Dresden in Germany tested volunteers to see if cortisol levels in their saliva pointed to diseased arteries.

Each volunteer provided four saliva samples throughout the course of one day and underwent ultrasound tests to check for plaque deposits in their carotid arteries (in the neck).

The results showed those with the highest cortisol levels also had the largest build-up of plaques.
Posted: 10/29/2008 9:46:00 AM

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Saliva DNA may solve drug dosing problems


U.S. scientists say they're using DNA extracted from saliva to customize prescriptions and solve dosing problems that often confound doctors and patients.

By using DNA to customize a prescription, researchers at Temple University's School of Pharmacy hope to prevent adverse drug reactions. At the top of the list of problem drugs is warfarin (Coumadin), the most widely prescribed anticoagulant.

The researchers say they're trying to find the correlation between genotypes and the correct dosage of warfarin. By collecting saliva samples and extracting DNA, the scientists can look for variances in genetic clues that make people metabolize the same drug in very different ways.

"Our findings have confirmed there is a genetic variance of certain genotypes that correlate to how these participants respond to this drug," said Associate Professor Nima Patel, one of the investigators. "So, if you have this genotype, we can conclude what your risks may be, based on your DNA."

That would allow doctors to prescribe the correct dosage of warfarin and decrease the risk of adverse drug reactions.

Posted: 10/29/2008 9:44:00 AM

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Sedative Could Be Deadly in People With Seizures

From U.S. News & World Report:

Use of the sedative propofol is associated with a high risk for complications and even death in patients with prolonged seizures, according to a study by researchers at the Mayo Clinic in Rochester, Minn.

The study included 39 patients with refractory status epilepticus (RSE) -- prolonged seizures that don't respond to initial treatment. The condition occurs in patients with primary epilepsy and in those with other conditions such as trauma, tumors and infections that affect the brain.

Propofol is used to treat patients with RSE, but is more commonly used for sedation during surgery or other patient procedures. In those situations, propofol is used at a much lower dose and shorter duration than when it's used to treat RSE, according to background information in an American College of Chest Physicians news release on the Mayo study.

"Patients with RSE treated with propofol are at high risk for propofol-related side effects because of the high propofol infusion rates and prolonged treatment duration necessary in these patients. However, it is well described that propofol toxicity can occur even with brief exposure to the drug," study author Dr. Vivek Iyer, of the Mayo Clinic, said in the news release.

In the study, 39 patients (average age 54) were admitted to the intensive care unit with RSE. Thirty-two received propofol for a median of 63 hours and a median peak infusion rate of 67 micrograms per kilogram per minute. The other seven patients received other drugs, such as midazolam and pentobarbital.

In the propofol group, three patients had sudden unexplained cardiac arrest, resulting in two deaths. There were no deaths in the other group.

Thirty percent of patients in the propofol group experienced propofol infusion syndrome (PRIS), a serious complication defined by the unexplained presence of at least one or more of the following: the blood disorder known as metabolic acidosis; rhabdomyolysis (a muscle disorder); bradycardia (lowered heart rate); and/or cardiac arrest. PRIS occurred in one patients in the other group.

The findings indicate that doctors should be cautious in the use of propofol to treat patients with RSE, Iyer said.

"There are several other medications we can turn to in the case of uncontrolled seizures," he said. "Alternative agents should first be tried for patients with RSE, and propofol should only be used after exhausting all other options."

The study was to be presented Tuesday at CHEST 2008, the annual international scientific meeting of the American College of Chest Physicians, in Philadelphia.

Posted: 10/28/2008 1:52:00 PM

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Top 10 Human Medications That Poison Our Pets

From The American Society for the Prevention of Cruelty to Animals (ASPCA) :

Although pet parents are well aware of poisons lurking around their home, many don’t realize that some of the biggest culprits are sitting right on their own nightstands. In 2007, the ASPCA Animal Poison Control Center received 89,000 calls related to pets ingesting over-the-counter and prescription medications. To help you prevent an accident from happening, our experts have created a list of the top 10 human medications that most often poison our furry friends.

NSAIDs (non-steroidal anti-inflammatory drugs) like ibuprofen or naproxen are the most common cause of pet poisoning in small animals, and can cause serious problems even in minimal doses. Pets are extremely sensitive to their effects, and may experience stomach and intestinal ulcers and—in the case of cats—kidney damage.

Antidepressants can cause vomiting and lethargy and certain types can lead to serotonin syndrome—a condition marked by agitation, elevated body temperature, heart rate and blood pressure, disorientation, vocalization, tremors and seizures.

Cats are especially sensitive to acetaminophen, which can damage red blood cells and interfere with their ability to transport oxygen. In dogs, it can cause liver damage and, at higher doses, red blood cell damage.

Methylphenidate (for ADHD)
Medications used to treat ADHD (Attention Deficit Hyperactivity Disorder) in people act as stimulants in pets and can dangerously elevate heart rates, blood pressure and body temperature, as well as cause seizures.

Fluorouracil—an anti-cancer drug—is used topically to treat minor skin cancers and solar keratitis in humans. It has proven to be rapidly fatal to dogs, causing severe vomiting, seizures and cardiac arrest even in those who’ve chewed on discarded cotton swabs used to apply the medication.

Often the first line of defense against tuberculosis, isoniazid is particularly toxic for dogs because they don’t metabolize it as well as other species. It can cause a rapid onset of severe seizures that may ultimately result in death.

Pseudoephedrine is a popular decongestant in many cold and sinus products, and acts like a stimulant if accidentally ingested by pets. In cats and dogs, it causes elevated heart rates, blood pressure and body temperature as well as seizures.

Many oral diabetes treatments—including glipizide and glyburide—can cause a major drop in blood sugar levels of affected pets. Clinical signs of ingestion include disorientation, lack of coordination and seizures.

Vitamin D derivatives
Even small exposures to Vitamin D analogues like calcipotriene and calcitriol can cause life-threatening spikes in blood calcium levels in pets. Clinical signs of exposure—including vomiting, loss of appetite, increased urination and thirst due to kidney failure—often don't occur for more than 24 hours after ingestion.

Baclofen is a muscle relaxant that can impair the central nervous systems of cats and dogs. Some symptoms of ingestion include significant depression, disorientation, vocalization, seizures and coma, which can lead to death.

Posted: 10/21/2008 9:47:00 AM

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NSAIDs Might Lower Breast Cancer Risk

From Everyday Health:

Non-steroidal anti-inflammatory drugs (NSAIDs) are associated with a reduced risk for breast cancer, a new review suggests.

But the findings aren't an invitation for all women to start popping the popular painkillers, the researchers added.

"We don't want that to happen here, for people to jump on the bandwagon and start taking aspirin or ibuprofen," said study senior author Mahyar Etminan, an assistant professor of medicine at the University of British Columbia. "A lot of people are taking these drugs for aches and pains, and aspirin to prevent cardiac events. Those people may actually get an added benefit, but, for someone relatively healthy, we don't recommend starting to [reduce breast cancer risk] as of yet."

"From a practitioner's standpoint, it's kind of reassuring to patients if they do take NSAIDs for whatever reason," added Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. "I don't think women should be taking these medicines for prevention, but if they are taking them for other reasons like heart prevention or arthritis, this should be reassuring."

The study is in the Oct. 15 issue of the Journal of the National Cancer Institute.

Use of NSAIDs has been linked to a lower risk of cancer overall, particularly colon cancer, and even to a lower risk of breast cancer, although studies looking specifically at breast cancer have produced inconsistent results.

With colleagues at the University of Santiago de Compostela in Spain, Etminan reviewed mostly observational studies which, together, involved a total of almost 3 million women.

The analysis included the group of NSAIDs known as cox-2 inhibitors, only one of which, Celebrex (celecoxib), is still on the market.

NSAID use across all participants in all studies was associated with a 12 percent lower risk of developing breast cancer. Aspirin was associated with a 13 percent reduced risk, and ibuprofen with a 21 percent reduced risk.

Different doses did not yield different results.

The authors acknowledged that, given that almost all of the studies reviewed were observational, this analysis may be subject to the certain limitations, and all such analyses are only as good as the studies they review.

On the other hand, the review was a large one and has biological plausibility. The inhibition of the enzyme cyclooxygenase (COX) is thought to be one of the ways NSAIDs might reduce cancer risk. And, according to an accompanying editorial, cox-2 is over expressed by 40 percent in invasive breast cancer and 80 percent in colorectal cancer.

At the very least, the results should prompt further research.

"The question is, how can you apply these results? These drugs are widely used but not without side effects. You're not going to put someone on ibuprofen long-term, because it's not going to help the stomach, and there are kidney effects," said Dr. Debra Monticciolo, a professor of radiology at Texas A&M Health Science Center and vice chair of research in the radiology department and chief of breast imaging at Scott & White Hospital. "This is preliminary. You're looking at an observational meta-analysis. It's not the strength of a randomized, controlled trial. You want long-term efficacy and long-term safety data. We need more information."

A randomized trial looking at the protective effect of Celebrex on breast cancer is due to be completed in 2009, Etminan said.

Posted: 10/14/2008 1:57:00 PM

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Docs double kids' vitamin D recommendations

From The Associated Press:

The nation's leading pediatricians group says children from newborns to teens should get double the usually recommended amount of vitamin D because of evidence that it may help prevent serious diseases.

To meet the new recommendation of 400 units daily, millions of children will need to take daily vitamin D supplements, the American Academy of Pediatrics said. That includes breast-fed infants — even those who get some formula, too, and many teens who drink little or no milk.

Baby formula contains vitamin D, so infants on formula only generally don't need supplements. However, the academy recommends breast-feeding for at least the first year of life and breast milk is sometimes deficient.

Most commercially available milk is fortified with vitamin D, but most children and teens don't drink enough of it — four cups daily would be needed — to meet the new requirement, said Dr. Frank Greer, the report's co-author.

The new advice is based on mounting research about potential benefits from vitamin D besides keeping bones strong, including suggestions that it might reduce risks for cancer, diabetes and heart disease. But the evidence isn't conclusive and there's no consensus on how much of the vitamin would be needed for disease prevention.

The new advice replaces a 2003 academy recommendation for 200 units daily.

That's the amount the government recommends for children and adults up to age 50; 400 units is recommended for adults aged 51 to 70 and 600 units for those aged 71 and up. Vitamin D is sold in drops for young children, capsules and tablets.

Besides milk and some other fortified foods like cereal, vitamin D is found in oily fish including tuna, mackerel and sardines.

But it's hard to get enough through diet; the best source is sunlight because the body makes vitamin D when sunshine hits the skin.

While it is believed that 10 to 15 minutes in the sun without sunscreen a few times weekly is sufficient for many, people with dark skin and those in northern, less sunny climates need more. Because of sunlight's link with skin cancer, "vitamin D supplements during infancy, childhood and adolescence are necessary," the academy's report says.

Posted: 10/13/2008 1:53:00 PM

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Bisphenol-A: The controversy continues

From Environment & Climate News:

A comprehensive study by the European Food Safety Authority (EFSA) reports products containing the chemical bisphenol-A are completely safe for human use.  The new findings, released July 23, authoritatively contradict the assertions of anti-chemical activists seeking to ban bisphenol-A in cities and states across the U.S.

After extensive study, an expert panel of scientists found potentially negative health complications of bisphenol-A identified in laboratory rats are not applicable to humans. The rats were fed much more bisphenol-A than humans can encounter, and the human body metabolizes and eliminates bisphenol-A much more efficiently than rats do.

Bisphenol-A poses no health threats to even the most vulnerable of human populations, such as infants, the elderly, and fetuses, EFSA scientists concluded.

“Bisphenol-A is safe as commonly used,” said Dr. Gilbert Ross, medical director for the American Council on Science and Health. “Typical exposures to bisphenol-A do not pose a health threat to humans of any age.”

Responding to assertions trace amounts of bisphenol-A have been detected in human biomonitoring projects, Ross said such trace consumption of bisphenol-A poses no health risk.

“We all have bisphenol-A in our bodies,” Ross said, “but this means nothing as far as human health is concerned. Saying that something is in our bodies is essentially meaningless. Just because something is found doesn’t mean it is a threat to human health. There has never been any evidence indicating any human health threat associated with bisphenol-A.”

However, from

In addition to its association with cancer, hormonal problems, liver abnormalities, diabetes, and heart disease, exposure to bisphenol A (BPA)—the chemical the U.S. Food and Drug Administration (FDA) has deemed safe—has now also been found to reduce the effectiveness of chemotherapy treatments, according to University of Cincinnati (UC) scientists.

UC’s Nira Ben-Jonathan, PhD, led the study that found BPA induces a protein group that protect cancer cells from chemotherapy. “Resistance to chemotherapy is a major problem for cancer patients, especially those with advanced or metastatic disease,” says Ben-Jonathan, professor of cancer and cell biology at UC who has studied BPA for over 10 years. “Finding out what contributes to that resistance can give us an idea of what to target in order to make chemotherapy as effective as possible.”

Researchers suspect that BPA could play a role in cancer because of its structural similarities to a cancer-promoting compound called diethylstilbestrol (DES). “BPA does not increase cancer cell proliferation like DES does,” she says. “It’s actually acting by protecting existing cancer cells from dying in response to anti-cancer drugs, making chemotherapy significantly less effective.” Ben-Jonathan’s team studied human breast cancer cells, dosing them with low BPA levels consistent with levels found in the blood of human adults. The team found that BPA is acting in cancer cells similar to the way estrogen does—by inducing proteins that protect the cells from chemotherapy agents. Estrogen’s protein-inducing action has been linked to chemotherapy resistance; however, researchers have been unable to explain why this resistance occurs in some patients with less estrogen. Ben-Jonathan says her team’s research has important implications for this subgroup of patients.

“Patients with less circulating estrogen—post-menopausal women, for example—can also suffer from chemotherapy resistance,” she says. “Linking BPA to this problem gives us one more avenue to explore in terms of preventing chemotherapy resistance.”

“These data,” study authors write, “provide considerable support to the accumulating evidence that BPA is hazardous to human health.”

Posted: 10/13/2008 1:43:00 PM

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'Energy' Drinks Spark Alarm

From The Washington Post:

Researchers are calling for warning labels and other steps to curb the abuse of those wildly popular high-caffeine "energy drinks."

Roland Griffiths of Johns Hopkins University and 98 other experts sent a letter to the Food and Drug Administration this week saying they had become increasingly alarmed about Red Bull and similar caffeine-laced beverages.

The researchers cited a paper Griffiths and his colleagues recently published in the journal Drug and Alcohol Dependence, which noted that Americans are already spending billions on such drinks annually. Hundreds of new products are being introduced each year and sales are increasing rapidly. The advertising campaigns tend to target teens and young adults, especially young males, and, Griffiths and his colleagues say, appear to glorify illicit drug use.

In addition to other ingredients, the products contain as much as 500 milligrams of caffeine per can or bottle. To put that into perspective, a regular 12-ounce can of cola has about 35 milligrams of caffeine and a six-ounce cup of coffee has between about 77 and 150 milligrams.

The researchers are worried about all sorts of problems. Too much caffeine can lead to "caffeine intoxication," which can cause nervousness, anxiety, restlessness, insomnia, stomach problems and even rapid heartbeats and death in rare cases.

And that's not all. There's mounting evidence that young people who use these drinks are much more likely to go on to use prescription stimulants, raising concern they serve as a "gateway" to more serious drug abuse. There's even an energy drink additive called "Blow" which resembles cocaine powder and is sold in vials with a mirror and plastic cards, as well as another one called "Cocaine."

The researchers noted that Canada and many European countries require these drinks to carry labels warning about their high caffeine content and cautioning against mixing them with alcohol. Some ban certain products altogether.

In contrast, in the United States energy drinks are virtually unregulated. No labeling is required. They don't even have to list how much caffeine they contain, even though they may have a lot more than over-the-counter stimulants like NoDoz, which are required to carry warnings.

And from WalesOnline:

Its white powder lettering and deeply suggestive flavour titles seem designed to arouse suspicion. But it is the name of this new high-energy caffeine drink that is sending doctors, parents and anti-drug campaigners into a tailspin. Branded as the “legal alternative”, Cocaine has three-and-a-half times as much caffeine as Red Bull, and comes in three flavours – “regular”, “cut” and “free”.

American firm Redux, which is behind the drink, described the branding as “just a bit of fun”. But experts last night criticised the company as “cynical and irresponsible” and warned how it could glamorise the Class A drug.

The drink is currently only sold in the US, but is likely to be on its way to the UK.  The US version of the drink also contained wasabi and cinnamon, which numbed the throat to mimic the effect of taking cocaine for drinkers.

The Cocaine drink, due to be distributed in the UK by Netherlands-based Top Drinks, will take its place among a variety of drinks which have become popular in the UK as a quick energy boost or as an alcohol mixer.  A study found that men who combined energy drinks with alcohol felt alert and sober, even though they were actually drunk.  And since both alcohol and energy drinks dehydrate the body, when combined they can cause the body’s fluids to drop to dangerous levels.

The high caffeine content of energy drinks has worried health experts in the wake of damning reports of its negative long-term effects, particularly on young people, at who energy drinks are marketed. Cocaine has 250% more caffeine than market leader, Red Bull; the equivalent of seven cups of strong coffee. Red Bull has 80mg of caffeine in a 250ml can, whereas Cocaine has 280mg in a similarly sized can.

Posted: 10/9/2008 1:51:00 PM

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FDA rejects ban on child cold medicines

From the Associated Press:

A top government health official rejected the idea of an immediate ban on cough and cold medicines for young children, saying it might cause unintended harm.

Food and Drug Administration officials at a public hearing Thursday said they need to gather more data on whether over-the-counter remedies are safe and effective for children ages 2 to 6.

The FDA is also worried that a ban — as sought by leading pediatricians' groups — might only drive parents to give adult medicines to their youngsters.

With a new cold season coming, pediatricians are urging the government to demand a recall of over-the-counter cough and cold medicines for children younger than 6. The effectiveness of the medicines in children was never scientifically established, critics say, and problems with the drugs send thousands of kids to the emergency room every year.

The FDA this year warned against giving OTC cold medicines to children younger than 2. At that time, officials said they expected to decide by spring on recommendations for youngsters up to 11. Now the agency is seeking more advice from doctors, industry and consumers — and officials are not giving a timetable for a decision.

The industry says OTC medicines have been used for decades in treating kids' colds and are safe for those older than 2. Nonetheless, manufacturers are planning to carry out new studies involving the most common ingredients in the medications. The companies voluntarily stopped selling cough and cold medicines for babies and toddlers last fall.

FDA advisers said that was not enough and recommended that the drugs not be used for children younger than 6. An expert panel said children older than 2 could keep taking the medications while studies are undertaken to settle scientific questions about safety and effectiveness.

It turns out that when the FDA set standards for cough and cold medicines some 30 years ago, no separate studies were done for kids.

Cough and cold medicines send about 7,000 children to hospital emergency rooms each year with symptoms ranging from hives and drowsiness to unsteady walking. Low doses of a medicine are not likely to cause a problem; the main risk comes from unintentional overdoses.

The same ingredients usually are found in different products. For example, giving a child a cough syrup and a decongestant could inadvertently lead to an overdose.

The Consumer Healthcare Products Association, which represents the manufacturers, says preventable errors are the problem, not the safety of the ingredients in the medicines. The industry is starting an educational campaign aimed at parents, doctors and day care providers on the importance of following directions and storing medicines in places where kids cannot get at them.

Posted: 10/3/2008 11:29:00 AM

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