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Journal Club: Magnetic field-induced DNA strand breaks in brain cells of the rat

Ok, this one is a little bit out of my field, but the topic intrigued me. Found the article through a posting at ScienceDaily.

I’m always a little bit sceptical about claims on the effects of EM fields on tissue and the brain in particular. Mostly because many of the studies that show an effect use conditions that the majority of people aren’t exposed to in real life for significant periods of time. And there really isn’t a lot of energy in low frequency EM radiation (in the radio wave and low frequency microwave end of the spectrum) to do much more than re-arrange electron configurations. Maybe that’s enough though. Who knows. It’s a lot like extrapolating the effects of low level and chronic radiation exposure when all you’ve got is data from high level and acute exposures.

The article (Lai H, Singh N P, “Magnetic Field-Induced DNA Strand Breaks in Brain Cells of the Rat“, Environ Health Perspect, publication pending, doi:10.1289/ehp.6355) has been accepted for publication, but hasn’t been published yet. The PDF of the pre-publication version of the article is available here for the time being.

Going to try to read this one over the weekend and see what interesting tidbits it contains.

Abstract:

In previous research, we found that rats acutely (2 hrs) exposed to a 60-Hz sinusoidal magnetic field at intensities of 0.1 – 0.5 mT showed increases in DNA single and double strand breaks in their brain cells. Further research showed that these effects could be blocked by pretreating the rats before exposure with the free radical scavengers melatonin and N-tert-butyl-α-phenylnitrone, suggesting the involvement of free radicals. In the present study, effects of magnetic field exposure on brain cell DNA in the rat were further investigated. We found that: (1) Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hrs caused a significant increase in DNA single and double strand breaks. Prolonging the exposure to 48 hrs caused a larger increase. This indicates that the effect is cumulative. (2) Treatment with Trolox (a vitamin E analog) or 7-nitroindazole (a nitric oxide synthase inhibitor) blocked magnetic field-induced DNA strand breaks. These data further support a role of free radicals on the effects of magnetic fields. (3) Treatment with the iron-chelator deferiprone also blocked the effects of magnetic field on brain cell DNA, suggesting the involvement of iron. (4) Acute magnetic field exposure increased apoptosis and necrosis of brain cells in the rat. We hypothesize that exposure to a 60-Hz magnetic field initiates an iron-mediated process (e.g., the Fenton reaction) that increases free radical formation in brain cells, leading to DNA strand breaks and cell death. This hypothesis could have an important implication on the possible health effects associated with exposure to extremely-low frequency magnetic fields in the public and occupational environments.

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Friday Five

When was the last time you…

1. …went to the doctor?
About a year ago for my annual physical

2. …went to the dentist?
Probably far too long ago. I think maybe 8 or 9 years or so.

3. …filled your gas tank?
About 3 weeks ago.

4. …got enough sleep?
Sleep? I always get enough sleep.

5. …backed up your computer?
Home computer was backed up about a month ago, work computer
probably too long ago. That one’s a little overdue.

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Blogging by PDA

Testing a Palm conduit (plog) that lets you write blog entries in an app you load onto your PDA, then sync them to your blog. It uses MT’s XML-RPC interface to create the blog entry. So now you can blog from anywhere! Of course it doesn’t show up until you sync, but for us non-wireless PDA plebe/owners, it’s better than nothing.

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Love my T3

I’ve been playing with my T3 for a few days now, and I absolutely love it. Screen is nice and bright, sharp, colourful, and I absolutely love the extra screen space when you slide it open. Really makes using spreadsheets a lot easier (which is something I do a lot of). The screen is easy to read in the daylight and battery life is pretty good. Used it quite a bit to test a couple of x-ray rooms the other day. 5 hours of hard use along with lots of syncing and the battery indicator was down to about 40%. And it’s fast. Being able to switch between portrait and landscape mode is pretty cool to. The thing can handle pictures and music (comes with a Palm version of RealOne) too. Also comes with a webbrowser, but haven’t had the opportunity or need to use it yet.

The virtual grafitti area is pretty cool. Collapsing it gives you a bunch of extra screen real estate. One thing I would like to see is the ability to customize the buttons in the virtual grafitti area, like the hardware buttons can be customized. Since it is virtual, I don’t see any reason why they couldn’t be customizable.

Syncing is really fast too. Way faster than my Visor with USB. Already have it loaded up with about 10 MB of stuff, and a complete sync including backing up all the contents of the T3 only takes 2-3 minutes.

It has Bluetooth, which at the moment isn’t too useful for me yet. Maybe I’ll find something to use it for.

Migrating from my Visor was easy too. Sync my Visor, and rename the backup directory. Install the updated Palm Desktop, attach the cradle and sync my T3. All the contacts, datebook, todo and memos were transferred over seamlessly. I use Datebk5 and had to recategorize some of my datebook entries though. Some of the events got mixed up into different categories. Minor inconvenience. Then it was just a matter of dragging the apps I wanted to transfer out of the old backup folder to Palm’s QuickInstall tool and doing another sync.

Still carry my Visor Platinum around, just in case there’s something I need that I forgot to transfer over, but soon it will be relegated to sitting in my desk drawer. Anybody want to buy a used Visor Platinum? Good condition, just needs a new screen (digitizer is flaking out). Comes with USB and serial cradles, Stowaway keyboard (starting to suffer a little bit of wear and tear), Memplug and Vaja case. I think I’ve even got a few extra styli lying around I can throw in. Make me an offer if you’re interested.