November 4th, 2007 by Dr. Val Jones in News
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Harvard researcher, Dr. George Church, is spearheading a project that would make complete personal genome mapping available for a mere $1000. I read his research subject recruitment disclaimer. Here is a choice excerpt:
Volunteers should be aware of the ways in which knowledge of their genome and phenotype might be used against them. For example, in principle, anyone with sufficient knowledge could take a volunteer’s genome and/or open medical records and use them to (1) infer paternity or other features of the volunteer’s genealogy, (2) claim statistical evidence that could affect employment or insurance for the volunteer, (3) claim relatedness of the volunteer to infamous villains, (4) make synthetic DNA corresponding to the volunteer and plant it at a crime scene, (5) revelation of disease lacking a current cure.
I wonder what personal genome mapping means from an ethical and legal perspective? Are we equipped to handle the possible privacy violations and prejudice inspired by DNA coded predispositions? On the one hand, customizing medical treatment to a person’s genes offers some of the best hope for optimal care and cures. On the other hand, having your genes on public display could put you at risk for the five problems described by Dr. Church.
These are exciting and frightening times.This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
November 1st, 2007 by Dr. Val Jones in News
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A recent research study suggests that as many as 7% of adults over 45 have had a stroke without even realizing it. Researchers performed brain MRI scans of 2000 “normal” (asymptomatic) Dutch men and women between the ages of 45 and 96, and found that 7.2% of them (145 people) had evidence of an infarct (stroke), 1.8% (36 people) had small aneurysms, and 1.6% (32 people) had benign tumors (usually a small malformation of the blood supply to the brain).
Interestingly, they also found one person with a primary brain cancer, one person with a previously undiagnosed lung cancer that had metastasized to the brain, one person with a life-threatening subdural hematoma (brain bleed), and one person with an aneurysm large enough to require surgery. So altogether, they found 4 people out of 2000 who needed urgent medical intervention.
Although the authors of the article emphasized the point that many “normal” people have harmless brain abnormalities – I was a bit surprised by the fact that they found 4 asymptomatic people unaware of a ticking time bomb in their brains.
Keep in mind that the study was conducted on middle class Caucasian adults in the Netherlands – so we cannot generalize these findings to more diverse populations. But I do think it’s a bit of an eye-opener.
MRI scans are quite expensive (well over $1000 in most cases) and are therefore not offered to the general population as a screening test. But it does make you think about saving up for one. Your radiologist may find something unimportant, or she may find something that you hadn’t bargained for. Or maybe one day the technology will be inexpensive enough to offer as a screening test in a primary care setting. But that’s not going to happen any time soon.This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
October 21st, 2007 by Dr. Val Jones in Expert Interviews
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As Halloween approaches, I was asked a really interesting psychological question from Lauren (of Love, Lauren fame) at Revolution Health. She asked, “Why do people like to be frightened? I don’t like horror movies or haunted houses, but some people love that stuff. Why, Dr. Val?”
I scratched my head and looked at her for a moment as images of Saw, Freddie Kruger, and Jason Voorhees (the only Dutch Halloween “slasher” protagonist I know) went through my mind. I offered an unsatisfactory reply, and promised to take this up with someone more learned in the ways of fear. Luckily for me, Dr. Andrew Gerber– a thoughtful psychiatrist whose research focuses on brain response to emotion (how perfect) was up to the task. Here’s what he had to say:
Our enjoyment of being afraid is a wonderful example of how the human mind works in mysterious ways that are often not immediately transparent to our own introspection. Psychiatrists, psychologists, and cognitive scientists are coming up with new ways to study exactly these sorts of things (located in a psychological structure called the “dynamic,” “adaptive,” or “cognitive” unconscious) and have a variety of possible explanations.
1. We like to feel things strongly.
Even if something has a negative part to it, it can be overridden by our preference to feel something as opposed to nothing. This may be the same phenomenon that drives our curiosity (even when it gets us into trouble, like a cat), our restlessness, or the discomfort of boredom. Increasing evidence from brain imaging studies tells us that a large part of our brain is devoted to processing intense emotion. It’s pretty likely that these regions were very important in our evolution and survival as a species.
2. We love the experience of a building up of tension and relief.
The best part of all about being scared on Halloween or in a scary movie is the huge relief at the end when we or our hero emerges safe and sound. A part of us remembers the whole time that relief is coming, so the tension part is worthwhile. There are lots of experience in our life that have the same kind of tension and relief pleasure to them – for example, missing a loved one and then seeing them, being hungry and eating a delicious meal, or being really tired and then getting to relax. You might say that the more the tension builds, the more the relief feels good. Brain imaging studies show that motivational systems located in the deep and archaic part of the brain operate on a tension and relief principle. When this works well, we feel motivated to go about the business of our lives. This very system can go awry in disorders such as depression and drug addiction.
3. We like to work through old situations and make them come out better.
For better or for worse, humans are consummate problem solvers and when things didn’t go well in the past, we like to replay the situation and have it come out differently. We all recall the experience of being scared as a child when it didn’t feel so good. This makes it all the more fun as older children or adults to replay that experience but this time to have the experience come out in a more positive way.
And there you have it – our brains crave “tension and release” to feed parts of our large emotion-processing centers, we like to problem solve in controlled environments where the outcomes are not truly dangerous, and we derive pleasure from strong emotions. That being said, I prefer action flicks to the horror movies myself. Though I’m a sucker for a good Sci-Fi thriller. What about you? What’s your favorite “tension release” movie?This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
October 15th, 2007 by Dr. Val Jones in News
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I was always taught that chlamydia (a bacterial sexually transmitted infection) could cause infertility in women but didn’t affect men at all. Now it seems that male fertility may also be affected by chlamydial infections.
New research from Spain suggests that chlamydia can damage sperm DNA as well as their swimming ability. In fact, DNA damage in sperm from men infected with chlamydia is 3 times higher than in uninfected sperm. Also, fertility rates my be reduced by as much as 73% in couples infected with chlamydia.
Fortunately for men, their new sperm (produced after antibiotic treatment for chlamydia) appears to be normal/unaffected. For women, the damage is permanent. The crafty chlamydia bacteria crawl up into the fallopian tubes and create such an inflammatory reaction that the tubes are often scarred for life. Eggs released by the ovaries may be blocked from entering the uterus from narrowed and scarred fallopian tubes. This is why one chlamydial infection can put a woman at increased risk for ectopic pregnancy, miscarriage, infertility, and chronic pelvic pain.
It is estimated that as many as 1 in 10 people ages 18-25 are actively infected with chlamydia (in the US and Britain). The treatment can be as simple as one dose of oral antibiotics (1g of Azithromycin). Since chlamydia can be asymptomatic in men and women, and hard to diagnose in men in particular – I personally would recommend having both partners take a dose of Azithromycin before having unprotected sex in a monogamous relationship. Obviously, it’s always far better to have protected sex – but since 1 in 10 people have this infection, it seems pretty clear that people are not using condoms all the time. If you want to preserve your fertility – be vigilant about this infection. The good news here is that it’s easy to treat and can be prevented.This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
October 12th, 2007 by Dr. Val Jones in News
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The short answer is: yes. The longer answer is that Tasmanian devils (TDs), those feisty black and white Australian marsupials, are the first to suffer from it. In an enlightening story about the plight of these little guys, I learned that they are prone to a certain type of mouth cancer that they pass to one another through biting. Now, since biting is part of their mating rituals, this cancer has spread through the TD population like wild fire, even putting them at risk for extinction.
Why am I telling you this? Because it’s quite fascinating that cancer can be contagious. Sure we know that the human papillomavirus (HPV), for example, can be spread through sexual contact and may stimulate the body to produce cervical cancer cells eventually, but this is a more direct and faster method of transmission. Researchers have found that cancer cells in the mouth of the animal doing the biting slough off in the wounds on the other animal, and the cells grow into a new cancer in the injured animal.
So you may ask – can I get cancer from a TD? Not unless YOU’RE also a TD. The reason why the cancer cells can survive in the victim is because TDs have become so genetically similar to one another that foreign cells from another animal are not recognized and attacked by their immune systems. Human immune systems would recognize the TD cells as foreign and attack and kill them quite quickly.We humans can’t even accept an organ transplant from a family member without being on strong immunosuppressive medications.
Nonetheless, this case of contagious cancer is interesting – and makes me wonder if immunosuppressed humans could one day be vulnerable to developing cancer from another person’s cells. But that risk seems rather remote. For now, we should just feel sad for our furry friends down under. I know that at least Dr. Rob, the llama lover, will understand the grief.This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
