Health and Medicine – Page 23

Ptaquiloside Redux

Almost ten years ago, I wrote a feature article on the cancer risk associated with the bracken toxins known as ptaquiloside for ChemWeb. The article was updated and mirrored on Paul May’s Molecule of the Month website at Bristol University, and quite bizarrely still draws a few readers to the Sciencebase site via my byline on the article. I suppose the reason it is still popular is that it makes it to page on in Google should you search for the word bracken.

Anyway, this article occasionally triggers some rather interesting correspondence with readers. Most recently, John Nayler emailed me to ask whether or not toxic chemicals from bracken might leach into groundwater beneath bracken-infested areas. I had to admit I did not know, but a paper published recently in the journal Chemosphere (2007, 67, 202-209) discusses the microbial degradation and impact of ptaquiloside on soil microbes themselves, which sheds some light on the potential impact of this carcinogenic toxin.

Another of Nayler’s concerns regards whether or not bracken is not simply an unpleasant weed with a cancer risk associated with eating the “fiddle heads” (a delicacy in Japan), but whether or not landowners, whose land is infested with bracken might be liable for public health lawsuits should those with a right to roam on their land be exposed to bracken spores. The risk may be small but that never stopped an ambulance-chasing lawyer in the past.

Cancer Research UK has a FAQ on the cancer potential of bracken. Despite isolated ptaquiloside coming up positive in carcinogenicity tests a decade ago, the latest research, according to Cancer UK is that there is no risk of cancer associated with eating bracken fiddlehead greens. So, what about those spores. Studies have shown bracken spores to cause cancer in mice, but those mice were given a lot of spores and to extrapolate to human cancer risk is (death)wishful thinking. A walk among the bracken is more likely to trigger a sneezing fit if the spores are high than anything else, and as CRUK points out, diet and smoking are far greater risk factors than bracken for cancer.

I Know What I Did Last Summer

This is what we were posting about a year ago this month, some of these are just plain silly, others are quite informative, but most just seem to lead to one thing on the mind:

Seat of Female Libido Revealed – Researchers found the organ in the brain responsible for female sexual response, I have to admit I hadn’t realized it had gone missing.

Keeping the lead in your pipes – Organs were being fiddled with in churches across Europe

Sperm and eggs – a sexy paradox…in fruit flies.

Erotic brain – Medical scientists discovered that women’s brains light up when they are exposed to erotic imagery, you don’t say?

Coca Cola Blonde – Yuck! (No Photoshop involved, by the way)

Beer vs wine – Beer is better, more B (vitamins)

I’m not sure if there is any kind of running theme here, (sex, booze…?), maybe it was just the time of year, the silly season was upon us, or you could probably even blame global warming.

Genetic Research Hits Pay Dirt

DNA The budget for the Human Genome Project and all that post-genomic, proteomic, metabonomic, immunomic…research was almost on a par with defense spending; it was almost c-omical really. Well, maybe not quite, but it stretches out with a lot of zeros nevertheless. At the time the grants were written and the funding given, we, as a society, were promised all kinds of medical miracles from gene therapies and new treatments to cure all those nasties – cystic fibrosis, sickle cell, thalassemia, cancer, heart disease and more.

We were promised personal medicine courtesy of pharmacogenomics. This would allow your doctor to profile your genome and tailor your medication to the particular set of enzymes running in your liver and whether or not you were likely to respond positively, suffer adverse effects, or simply not respond at all. We have even seen, this last few days, the sequencing of James Watson’s genome; an effort that cost less than $1m and took under four months. But do any of these promises add up to very much beyond myriad PhD theses and thousands of biotech startups many of which have already crashed?

Hopefully, the answer is yes. In the next few years, gene science will hit pay dirt as genes finally give up their real secrets and the true meaning of so-called junk DNA will become clear. Our understanding and ability to treat a wide range of disease from breast cancer and obesity to hypertension and bipolar disorder will come of age and perhaps finally succumb to all this genetic scrutiny and manipulation.

Nature, Science and the Wellcome Trust provided a useful summary of the genetic state of the art for a recent Times report by Mark Henderson on our genetic future. In the summary Henderson highlighted the latest “in press” results, most of which are now online, so I am providing here the hyperlinked executive summary:

Breast cancer – Three papers published in Nature and Nature Genetics at the end of May reported four new genes and one genomic region associated with increased risk. 10.1038/nature05887, 10.1038/ng2075, 10.1038/ng2064

Obesity – An obesity gene, the FTO gene, was published in Science in April and reported in Sciencebase at the time.

Diabetes – Again in Science (and 10.1126/science.1142382 and 10.1126/science.1142358, three common genes for increased diabetes type 2 risk were reported, bringing the total known genes associated with diabetes to nine.

Alzheimer’s disease – New results also published this week in Neuron discuss an Alzheimer’s gene

Data that were still under press embargo at the time Henderson’s feature appeared in The Times, however, meaning he could only hint at the true potential of human genome results were revealed today.

The largest ever study of genetics of common diseases in which almost 10 billion pieces of genetic information were analysed were published just one minute ago, so I can now outline the findings in a little detail. The new study compared 2000 cases each of seven common diseases with 3000 shared control patients, and reveals new genetic associations with these disorders. A pair of related papers in Nature Genetics (a and b) offer further insights into two of the seven diseases investigated.

In the Nature article, scientists from the Wellcome Trust Case Control Consortium report genetic variants associated with the development of bipolar disorder, Crohn’s disease, coronary heart disease, type 1 and type 2 diabetes, rheumatoid arthritis and hypertension. This is the first study from this large scope and it, the scientists found one genetic region newly associated with bipolar disorder, and another with coronary artery disease. A separate group of three markers have been found to be associated with rheumatoid arthritis. The researchers also identify nine new genetic associations for Crohn’s disease and ten chromosome regions that contain genes related to diabetes.

These new results would suggest a medical revolution is at hand and that the Human Genome Project and its spinoff -omics really are about to hit pay dirt. But, are we really on the verge of a new era in medicine, or are the various genetic revelations simply more grant-baiting hyperbole?

Udderly butterly

Cow Scientists in New Zealand hope to breed cows to produce low-fat, skimmed milk, not only that they are working on a new bovine breed that will produce milk that makes spreadable butter.

Apparently herd member Marge and her sisters and cousins, have the right genetic makeup required for producing skimmed milk straight from the udder and milk that makes and easily spreadable butter. The team hope to partner up with a friendly bull soon and have a commercial herd ready by 2011. Even more importantly from the human health perspective for those whole like the “white stuff” on their cereals in the morning, Marge’s milk is very low in saturated fats and so her offspring will hopefully produce high polyunsaturates and monounsaturated fat milk too.

Ed Komorowski, technical director at Dairy UK says that the New Zealand approach could be used to breed cows that still produce full-fat milk but with only the good fats, which could swing things back in favour of full-fat milk. In the UK, for example, only 25% of milk sold is full fat. “In future if whole milk can be made to contain unsaturated fats — which are good for you — then it might mean that people change back to whole milk products. The big thing about dairy products is taste, so this would be a way of giving the benefits of taste without the disadvantage of saturated fats,” he adds.

Milk from this new healthy breed of cattle could also overcome the problem of what to do with all the waste products of the dairy industry that are produced during the fat-reduction process. “If you can genetically produce milk without fat then that may turn out to be a very good solution to what might later be a big disposal issue,” says Komorowski.

The healthy cows were identified biotech company ViaLactia while screening milk compositions across the entire herd of 4 million New Zealand cattle. New Zealand dairy firm Fonterra has already made milk products from Marge’s milk and they maintain the positive taste.

The research is discussed in more detail in this week’s issue of Chemistry and Industry magazine from the UK’s Society of Chemical Industry.

Ignore your internal critic and relax

Blogger in a hammock This item could have been called “How to out-psyche yourself”, it is not exactly rocket science, but then rocket science is not one of the common topics on Sciencebase, anyway. It’s a public holiday here, today. Yes, I know…again? Oh, and over there too? Anyway, I’ve pulled together some of the chillingest out posts from the last week or so and brought them together in an easy to catch, laid back post with few words, and a hammock on stand by in case the sun comes out. Incidentally, almost all these tips, or life-hacks as some people are wont to call them basically boil down to a simple phrase, that any analyst, physician, or psychiatrist could do well to hang on their surgery door, desk, and above their sphigmomanometer – Don’t Worry, Be Happy.

So, over on lifehack itself, they posted a top ten of simple ways to save yourself from messing up your life. Seems like heavy psychological stuff from the title, but it boils down to not worrying about your feelings, taking life in your stride, and avoiding dwelling on the ramblings of your internal critic. So far, so good.

Next, over on the American Lung Association site – heart I could understand, but lung? – they are touting, not ten, not twenty, not even fifty, but fifty-three (don’t ask), surefire ways to help you chill on any day of the week not just a public holiday. Among my favourites, is “Count to 1,000, not 10, before you say something that could make matters worse.” This goes for commenting on blog posts too: “Look, before you leap”, as my grandma used to say.

Some of the more “new-agey” stuff on the web often has a decent list of howtos for relaxation and such. I am not saying that WikiHow is new age, perish the thought, but they do have a how2relax section, with the classic: “Find a quiet place when you are feeling overwhelmed. Even the stall of a bathroom will work if you have no other place to go.” You can just picture all those overwhelmed office workers, “relaxing” in the bathroom, or maybe not, we do not want to revisit any kind of Ally McBeal moment on this site, thank you very much.

At this time of year, many poor unfortunates (PUs) will have to put aside worries about who is buying the next round, and concentrate on their exams. Thankfully, the venerable University of Cambridge offers those PUs, some useful advice on simple exam-time relaxation on their student counselling website. A classic tip offered there is: “don’t use your bed as a place to work during the day”. As if, have you ever heard anything so preposterous? Students using their beds to work on during the day? Of course not…

We now know how they do it in Cambridge, England, but what about across the Pond in that other townwise homonymous centre of excellence, Harvard University? Well, Harvard U, has a Relaxation Room, of course. “The body responds to stress with increased muscle tension,” so says the RR’s website and apparently in said room you can get a massage or give a massage. Now, I don’t know about you but I don’t recall any such offers while I was studying at university. How the times change.

Finally, an NYT article discusses how to deal with past bad experiences, not by ignoring them, but by retelling them in your internal narrative as if there happened to a third party rather than you.

Anyway, deciding the best way to relax is getting too stressful, I am going to fix that hammock and take that initial advice…the bit at the end of the first paragraph.

Toxic scaremongering

The Independent on Sunday today reports that a UK researcher is claiming that fizzy drinks which contain sodium benzoate preservative (E211) could be harmful to mitochondrial DNA in our cells. Apparently, Sheffield University molecular biologist Peter Piper tested the compound on yeast cells (one of the organisms the preservative is added to drinks to eliminate in the first place). More to the point, the levels at which he assaulted the yeast was the equivalent of a person drinking ten gallons of soda in one go.

This new scare story follows closely on the tail of the benzene in soda debacle Sciencebase reported last year and the almost historical tale of benzene contamination of mineral water scare of the early 1990s. Intriguingly, The Independent article does not seem to mention the words “dose” or “concentration” once.

Perhaps there are individuals who drink large volumes of soda every day without realising there are other harmful effects of such drinks, like the concentrated sugar intake, or the relatively high levels of caffeine stimulant. But, even high-speed Digger users only claim to drink a couple of litres of Mountain Dew each day, not the ten gallons equivalent of the experiments. Perhaps experiments will push the safety threshold well below 10 gallons (please excuse the mixed units), maybe even to 1 gallon, but that’s still an awful lot of soda for anyone, even for a hardened Digger, to be drinking every day, surely?

There are many reasons to not drink soda, so instead choose tap water, choose life…

No, wait a minute, fish do their four essential biological “F’s” in water – Feeding, Fighting, Fleeing…Fu Mating. Best stick to beer.

Balancing your gut bugs

Mouse Could those so-called “bio” yogurts and milk-type drinks with Scandinavian sounding names actually do you any good? Possibly.

According to a study published in the journal Molecular Systems Biology this week, microbial flora in the gut can profoundly affect how you absorb nutritients from your food and your overall health. Jeremy Nicholson and colleagues at Imperial College London suggest that keeping a balanced gut flora may prove important to prevent some human metabolic diseases. Those active yogurts and one-day milk substitutes containing live microbes could play a role in helping you maintain the balance.

Our guts are an internal ecosystem all their own. Quite bizarrely, the microbial community living in our intestines has 100 times as many genes as the whole of the human genome. It is almost as if those living inside you outrank you yourself. However, we rely on these microbes for the normal processes of digestion and waste disposal just as much as the microbes themselves need the lining of our intestine as their stamping ground. We, and all other mammals, are not so much individuals as “superorganisms”, a collective, a symbiotic biological system.

Nicholson and his team used metabolic profiling techniques to monitor changes in bile acid composition and lipid (fatty molecule) metabolism in mice whose gut flora had been replaced by human bacterial flora. Perhaps not surprisingly, the mice showed alteration in the composition of their bile acids and circulating lipoprotein levels, and displayed symptoms such as lipid accumulation in the liver that would eventually lead to disease. Closer inspection of the mouse gut, revealed that the human gut microbes could not form a strong and stable ecosystem.

Nicholson’s findings demonstrate that gut microbes control the absorption and storage of nutrients from our food and help us harvest its energy. They also show that the wrong type of microbes can lead to disease by affecting the chemical and metabolic balance of the gut and liver.

So, should you drink those liquid bio yogurts? If you can pronounce them easily then there is probably no harm in asking for them at your healthfood store, but the message is clear: steer well away from mice.

Possums, horses, and pigs do it

Brushtail possums, photo by wollombi http://www.flickr.com/photos/wollombi/ I just received an early publication alert from the Australian research organisation CSIRO announcing the imminent publication of volume 19 of their journal on reproductive science, fascinating I thought as I opened the attachment.

First up in the list of contents was a paper that sounded rather intriguing from FC Molinia and colleagues entitled: “Uterine and vaginal insemination optimised in brushtail possums (Trichosurus vulpecula) superovulated with pregnant mare serum gonadotrophin and porcine luteinising hormone”.

So, let us just dissect what that convoluted title actually means. Basically, they stimulated brushtail possums with hormones from a horse and a pig to make it produce more eggs than normal and then artificially inseminated the females, with brushtail possum sperm, obviously. I am pretty sure it is all standard procedure for getting those little brushtails up the duff, and it is not so odd that they used horse hormones in the process, after all, one form of human hormone replacement therapy uses equine estrogen.

Something worries me a lot about this particular EarlyAlert. The abstract says that artificial insemination of brushtail possums (Trichosurus vulpecula) is being developed as an assisted breeding model for endangered marsupials, as well as a bioassay for testing fertility control vaccines to manage overabundant populations.

Hmmm…humans do not have a strong record on “assisting” animals in this way, and particularly not in Australia, I am thinking rabbits and mixomatosis, feral camels, and the infamous cane toad, to name but three. Why is it that we feel we can intervene and manage ecosystems in this way? The end results are usually disastrous and given the purportedly fragile nature of Australia’s ecosystems, should we not leave well alone?

The full paper can be accessed here.

Straight answers to health questions

Anahad O'Connor NYT reporter Anahad O’Connor sent me a review copy of his latest book, “Never shower in a thunderstorm”, which hits bookshelves in paperback this week. In it, O’Conner debunks, in the style of his regular “Really?” column, numerous health myths and misconceptions such as whether artificial light is hazardous to health, are bald men more virile (of course!), and is chicken soup good for treating the common cold?

Here’s a selection from his book, with the most straightforward answer I could extract from his excellent vignettes.

Can a glass of wine with your meal prevent food poisoning? Yes
Are ab machines the best way to build a six-pack? No
Will having sex before sports hinder your performance? No
Can having sex induce labour? No
Is yo-yo dieting unhealthy? Yes
Is bottled water cleaner than tap? No
Does packing a wallet in your back pocket cause sciatica? Yes
Do toilet seats spread disease? No
Is sitting up straight good for your back? No
Can loud music deafen you? Yes

If you want the complete explanation for his answers to these questions and many more, you will, of course, have to read the book.

Agony agonists and cancer combatants

In chemistry news this week, The Alchemist learns about slow-release drug formulations that prevent drug abuse, the risks of war associated with using depleted uranium in munitions and armour plating, and the analytical benefits of red wine that could turn up on labels to guide consumers to the most healthful Chianti or Zindanfel.

Also, this week, a well to wheel analysis reveals that hybrid cars are not as green as you would think and that converting natural gas to hydrogen for use in fuel cells could be the best environmental option for transport. Finally, web-savvy chemists using the Firefox browser have a new tool available to them that offers inline entries from blogs while they read ACS, RSC, Wiley, and other journal tables of contents.

This week’s grant goes to Bassam Shakhashiri for pioneering work in engaging the public with science and for helping to rebuild education programs after decimation by Reagan funding cuts in the 1980s.