Saturday December 7, 2013
I recently saw an article in our local paper surveying all the possible dangers of genetically modified organisms (GMOs). The piece argued for GMO labeling. Unfortunately, though, it was so full of inaccuracies about what GMOs are, what research has been done with them, and what impact they have had on agriculture, that any conclusions about how they should be managed or labels was completely undermined.
Perhaps one of the biggest misconceptions with this discussion of labeling and, in fact, most GMO debates, is that all GMOs are somehow all similar. Public discussion seems to consistently frame the debate between GMO vs. non-GMO crops, for example. In fact, GMOs are all unique, just as any other plant. GM-oranges different from GM-apples just as non-GM apples and oranges do.
The recently posted article, The Truth about GMOs: They Are All Different, discusses this point.
Friday November 22, 2013
Memory loss has been linked to marijuana use for...well...as long as I can remember. A recent report suggests common pain killers may limit this side-effect. However, they might also reduce pot's high too.
Tetrahydrocannabinol (THC), the main psychoactive chemical in marijuana, produces its psychological and physical effects by interacting with two receptors found on the surface of certain types of cells in the body. One of these receptors is found primarily on cells in the brain.
A few years ago, researchers found that THC's activation of this receptor on cells in the brain seemed to lead to the memory loss caused by the drug. Now, researchers at Louisiana State University's School of Medicine just published work showing that THC turns on an enzyme called cyclooxygenase-2 (Cox-2) when it activates this receptor.
You may have heard of Cox-2 in a different context. It is commonly associated with pain and swelling. Cox-2 inhibitors, such as Celebrex which is often prescribed for arthritis pain, help reduce pain and inflammation. In fact, most anti-inflammatory drugs that aren't steroids--like aspirin, ibuprofen and naproxen--are Cox inhibitors. They block with both Cox-1 and Cox-2 activity.
In the recent study, researchers didn't just find that THC activated Cox-2, but also that a Cox-2 inhibitor protected mice from memory loss that would normally be caused by days of injections with THC. In other words, blocking Cox-2 activation prevented THC-induced memory loss.
Of course, what is not clear is how high the mice with the Cox-2 inhibitor were. Actually, this is really an important question because THC provides effective treatment for many patients suffering from nausea, anorexia, and multiple sclerosis. There is also some evidence it may protect against neurodegeneration associated with Alzheimer's and Parkinson's disease.
If Cox-2 inhibition can prevent memory loss due to THC use in humans like it can in mice, but maintain the other desirable effects of cannabis, it would significantly improve marijuana's medical utility.
You can read the full study in the journal Cell and also get more details from a summary in Science.
Wednesday November 13, 2013
The virus for Middle East Respiratory Syndrome (MERS) has been found in the pet camel of a man from Jeddah in Saudi Arabia that was diagnosed with the disease last week. Researchers are currently comparing the virus isolated from the camel to see if it matches the variant in the patient.
The finding supports the idea that most people contract the disease from camels. Recent prior contact with camels was noted in several earlier MERS cases. However, being around camels is not so unusual in the Middle East and this is the first time the MERS virus has been confirmed in an animal in direct contact with the patient.
This newly identified MERS infection brings the total number of confirmed MERS cases to 154 since the summer of last year. 64 deaths have resulted from the virus so far. While the 40% mortality rate of the virus is quite high, it doesn't seem to easily transfer from human to human as compared with other viruses in the same family such as SARS.
At least the poor infectivity seems to have prevented an outbreak due the Hajj pilgrimage that marks the end of Muslim Ramadan. Over 1 million travelers visited Saudi Arabia from Oct 13 and ended on Oct 18. However, only one MERS case has been linked to the event to date--a Spanish woman diagnosed a couple weeks after returning home from the trip.
For more info on MERS, take a look at MERS: Deadly but Not So Easy to Catch.
Thursday November 7, 2013
Have you heard of the new genetic engineering tool that's the current rage in biotech labs--CRISPR? The headline in today's Science section of the British newspaper The Independent, 'Jaw-dropping' breakthrough hailed as landmark in fight against hereditary diseases as Crispr technique heralds genetic revolution, may be a bit overblown. It does, however, sum up the excitement in much of the scientific community about this technology.
For example, the article quotes from Craig Mello describing CRISPR as, "better than RNA interference....a tremendous breakthrough with huge implications for molecular genetics...a real game-changer." Craig Mello, of course, along with Andrew Fire won the 2006 Nobel prize in Medicine for their discovery of RNA interference (RNAi). With a name practically synonymous with RNAi, Dr. Mello's enthusiasm about CRISPR is certainly notable, as are the reactions of several scientists mentioned in the article.
If you are not familiar with CRISPR, it is a system bacteria use to chop up DNA from invading viruses. While that may not seem so exciting unless you are a microbe, it turns out that the key components of CRISPR, a protein and a small specially configured DNA, can be taken out of the bacteria and used to genetically engineer almost any DNA in any organism.
CRISPR provides a precise and convenient tool to manipulate DNA. Research labs have been eagerly adopting the technology to make genetic modifications. However, it also has real potential for use in gene therapy.
To find out more about how CRISPR was discovered, how it works, and what it can be do, take a look at CRISPR: What's All the Excitement About?.