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‘new zealand’s #1 way to lose weight’ – oh really? Alison Campbell Apr 02

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As I’ve said previously, I find Facebook good for keeping up with friends & family, & profoundly irritating in its practice of ‘targeting’ ads to the user. Mind you, that offers endless opportunities for blogging (when one can find the time). And today I shall make use of that opportunity, for today FB offers me a link to “New Zealand’s #1 way to lose weight” – and no, it’s not a combination of exercise & eating sensibly!

First up, although the purported writer claims to be a New Zealander looking at use of a particular ‘miracle’ combination in NZ & documenting her own results, I couldn’t help but notice that a) ‘New Zealand’ is mentioned but a single time in the blurb; b) she looks nothing like any of the women in her supposed ‘before & after’ photos (nor does she share a name with any of them – such sloppy editing, lol); & c) none of the women are from NZ.

Anyway, what’s she raving about? There seems to be a new ‘miracle weight loss/elixir of health’ offered every week (there’ve been ads pushing reservatrol in the papers recently, for example). This particular wonder is the fruit of Garcina cambogia (aka Gambooge), native to Indonesia but grown through South-east Asia and parts of India & Africa, where it’s widely used in cooking. However, it’s also been claimed to have significant health benefits: the page FB promotes says

It is known to contain the highest antioxidant concentration [not according to this study]  of any known food, and is reported by many to have unprecented weight loss and health benefits. By combining Garcinia Cambogia [sic] supplements with a natural colon cleanse…, many people claim that their bodies have literally become “fat burning machines”.

Ah, the wonders of pseudoscience – oxidation is required to ‘burn’ fat, so promoting an antioxidant to help lose fat sounds somewhat contradictory :) And colon ‘cleanses’ – money down the loo.

As for that claimed weight loss (the promotional web page claims 13 kgs!), well, the value of G.cambogia in achieving this has been put under the microscope. This approach is rather more reliable than relying on testimonials, even celebrity endorsements: like green coffee beans, gambooge has been promoted on Dr Oz’s TV show as a “revolutionary” new fat buster.

Yet it isn’t even new – its use has been studied for over 15 years. A study examining its potential as an anti-obesity agent, published back in 1998, concluded that

Garcinia cambogia failed to produce significant weight loss and fat mass loss beyond that observed with placebo.

And this meta-analysis of randomised clinical trials – published in 2011 – found that Garcinia extract (hydroxycitric acid) might cause short-term weight loss. However, they noted that in one trial those using the extract were more likely to suffer gastrointestinal upsets than people on a placebo, and went on to conclude that

The magnitude of the effect is small, and the clinical relevance is uncertain. Future trials should be more rigorous and better reported [my emphasis].

I’ll stick to the exercise/sensible eating combo – it’ll probably save me money too :)

 

S.B.Heymsfield, D.B.Allison, J.R. Vasselli, A.Pietrobelli, D.Greenfield & C.Nunez (1998) Garcinia cambogia (Hydroxycitric acid) as a potential antiobesity agent: a randomised controlled trial. JAMA 280 (18): 1596-1600. doi: 10.1001/jama.280.18.1596

I.Onakpoya, S.K.Hung, R.Perry, B.Wider & E.Ernst (2011) The use of Garcinia extract (hydroxycitric acid) as a weight-loss supplement: a systematic review and meta-analysis of randomised clinical trials. Journal of Obesity 2011. doi: 10.1155/2011/509038

 

caesarians & medical hypotheses Alison Campbell Apr 01

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Many moons ago I used to do the occasional talk for Parents Centre ante-natal classes, on what to expect during a caesarian delivery. (I’d experienced an emergency C-section, so was happy to let others know what was involved.) So it was to be expected that this op.ed piece in today’s NZ Herald (in the “Life & Style” section) would catch my eye. Initial interest turned to a thought that perhaps I was reading a spoof (check the date), but the paper described in this article does exist.

In January 2012 we brought together eleven researchers (midwives, scientists, epidemiologists, geneticists and epigeneticists) at the University of Hawaii and developed the EPIIC Hypothesis, which has just been published in Medical Hypothesis.

I did wonder in passing why epidemiologists & geneticists weren’t counted as scientists, but what stood out is the fact the paper was published in Medical Hypotheses. (Being charitable, I’ll assume the mis-spelling occurred in the editorial process.) In other words, there’s no requirement to present any data in support of the hypothesis under discussion.

We have known for a while now that caesarean section is linked to longer-term health implications for the child…

As one of the commenters on the Herald piece points out, correlation is not the same as causation. Surely the researchers are aware of this?

We hypothesise that events during labour and birth – specifically the use of the synthetic hormone oxytocin, along with antibiotic use and caesarean sections – affect the epigenetic remodelling processes and the subsequent health of the mother and child.

Oxytocin is produced in large quantities during a normal labour; what would be the impact of that on epigenetic changes around the time of birth? In fact, the authors point the finger at more than (synthetic) oxytocin & C-sections, including forceps & vacuum-assisted deliveries as those potentially exerting a harmful effect. In describing this hypothesis, the op.ed. writer seems to be ignoring the fact that in at least some cases not using those interventions could result in the considerably more harmful outcome of death for mother &/or child. (To be fair, things are narrowed down somewhat in the MH paper.)

In the EPIIC hypothesis, we propose that physiological labour and birth have evolved to exert eustress (a healthy, positive form of stress) on the fetus, and that this process has an epigenomic effect on particular genes, particularly those that programme immune responses, genes responsible for weight regulation, and specific tumour-suppressor genes.

This is an interesting use of the term ‘eustress’, since its definitions suggest that whether or not stress is ‘healthy’ depends on how the individual perceives that stress, & whether they are left with a ‘feeling of fulfilment’ after experiencing it. At what point would a ‘normal’ labour cease to be so, & start generating ‘non-healthy, negative’ forms of stress?

And how would this hypothesis be tested? The Medical Hypotheses paper (sorry; it’s behind a paywall) does suggest a possible research program: essentially a long-term project tracking outcomes in individuals who birth experiences range from

home births in the most familiar environment to the woman and without medical interventions … to those born after elective caesarean section for breech presentation where there are no underlying medical complications…

and including

various ethnic groups, gestational ages, maternal ages and socioeconomic backgrounds.

With so many variables listed, proper data collection & analysis would be an extremely complex task. There is no mention of how this might be properly blinded. And – as that same Herald commenter says – why not go for an animal model first? And publish the results in a mainstream journal?

chocolate! & just in time for easter Alison Campbell Mar 27

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For years the husband has insisted that chocolate is a health food. He’s also spun me the line that eating it is good for the rainforest, as the mature cacao trees apparently grow in mature forest. So he’ll be happy with the Herald‘s story on his sweet treat, which has the enticing title of “Sweet news: chocolate is good for you”, and comes direct from the Daily Mail, that fount of all things good in science reporting. (Not.)

Me? Not so much. Like cautious investors, I tend to subscribe to the view that if something sounds too good to be true, it probably is.

The item begins:

Just in time for Easter, it’s the news chocolate lovers have dreamt of – official confirmation that their favourite guilty pleasure can be good for you.

New research shows that eating just a single chocolate bar has a direct effect on the brain and may cut the risk of stroke.

The research on which the Daily Mail‘s story is based was published last week in the journal Neurology, to which – alas! – we don’t have a subscription. The brief excerpt I can see indicates that the researchers were building on an earlier publication:

Larsson et al. investigated the association between chocolate consumption and risk of stroke in men, concluding that moderate chocolate consumption may lower the risk of stroke. We performed a prospective mechanistic study that may suggest a potential mechanism for this observation.

A prospective study is one that takes a group of individuals & follows them for some period of time, studying the impact of various factors on that group; ‘mechanistic’ means that the researchers would be looking to explain their findings in terms of physical or biological causes. In this case they were interested in the impact of eating chocolate, & apparently found that this had an impact on blood vessels; specifically, on the stiffness of the vessel walls. It would be interesting to read the actual paper because I’d like to know, for example, which blood vessels were studied, & how they determined the ‘impact’ of chocolate on brain cells. It’s notable that there’s no indication of what constituent of chocolate might be involved in any possible outcomes, so it’s a very broad-brush, preliminary outcome.

In its timing this mirrors an earlier story, published just before Easter 2010. However, the 2010 story is much more balanced in scientific terms, pointing out the shortcomings of the earlier research (and that most newspapers Got It Wrong) & noting that while it was possible that eating a small quantity of chocolate might confer some benefit, the association between choccy consumption & health wasn’t particularly strong. (And in fact, reported chocolate consumption appeared awfully low – the ‘high intake’ group reported eating a mere 7.5g/day!)

In this week’s Daily Mail story, the lead researcher is quoted as saying that

We think a reduction in stroke risk may be caused by chocolate changing how brain blood vessels behave.

It’s a real pity that the DM left this next part of the message until the very end of the tale, but at least the paper does note that

chocolate also has a high sugar and fat content which can cause obesity – a definite risk factor for strokes.

Sounds like swings & roundabouts to me. I hate to dash the husband’s hopes, but it would be a leetle premature to add this putative benefit to his list of reasons to eat his favourite Whitaker’s bar :(

the amazing hCG ‘diet’, redux Alison Campbell Mar 02

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A while back, I wrote about the so-called hCG ‘diet’ drops: homeopathic drops that might just possibly (depending on dilution) contain a molecule of human chorionic gonadotropin (or maybe not), and which supposedly help one to lose weight.

Ooops, nearly forgot to mention that you need to accompany your daily dose of magic water with the greatly reduced food intake that is all you get on a 500 calories/day diet…

My attention was originally drawn to this… um… creative bit of marketing by spam emails, but these days you can buy the drops in New Zealand, as noted in the NZ Herald:

Government agencies are assessing the legality of a diet that promises people they will lose up to half a kilogram a day by using a homeopathic fertility hormone banned in the United States.

The diet, which is gaining popularity in New Zealand, involves taking a substance known as hCG and restricting food to 500 calories a day for up to 40 days.

The Herald article is reasonably sceptical – apart from the comment about taking “a substance known as hCG”: if this is truly a homeopathic preparation then all the purchaser is swallowing is water**. They would not be taking biologically-active quantities of the actual hormone (which is licensed in the US only as an injectable prescription drug).

And that amazing weight loss is pretty much what you’d expect on a diet that provides well below the calorie intake recommended for the average person.

** and remarkably expensive water, at that. According to the Herald, the NZ purveyor

sells a 23-day suppoly of hCG – human chorionic gonadotropin – for $135 and a 40-day supply for $180. Her cheapest option is an eight- to 10-day supply for $55.

You get 60ml for that $180…

But wait, there’s more: I notice they’re into ‘alkalising’ the body as well (another idea with no biological plausibility).

fear & loathing in the water Alison Campbell Feb 21

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The ‘fluoride in drinking water’ debate is heating up again in Hamilton. A letter in one of our local free newspapers begins

Sodium fluoride is the main ingredient in rat poison

and then informs us that the Nazis used it to keep their prisoners docile. And what I want to know is this: why, if the writer’s case against fluoridation is so strong, do they feel the need to use such scare tactics & to invoke Godwin’s Law? (Godwin’s Law is applied “especially to inappropriate, inordinate, or hyperbolic comparisons of other situations (or one’s opponent) with Nazis”: there does not appear to be any evidence that NaF was used in the way the writer describes, but it sounds scary & helps to demonise those with a different point of view.)

As for the ‘sodium fluoride/rat poison’ claim, even a quick search suggests otherwise (here, & here, for example). But it’s probably quite effective in promoting the ‘fluoride = poison’ idea in the public mind. However, as I (& others) have said before: the dose makes the poison.

I would have more respect for the writer’s point of view, were it not ‘bolstered’ with inaccuracies and scare tactics. But some things never change…

 

cyclists = road vermin? quit the hyperbole, mr ware Alison Campbell Feb 19

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It appears that Wellington businessman David Ware has a thing about cyclists: he has described them as “road vermin”, “roadkill”, and “weasels in lycra”. He is entitled to his opinion, but this is completely over the top. In fact, I have news for you, Mr Ware.

Yes, there are cyclists who demonstrate poor judgement & poor behaviour on the road. Failing to indicate, going through stop signs, that sort of thing. Funnily enough, I’ve seen the same in some car drivers. Stupidity, thoughtlessness, carelessness – yes! in all parties, on two wheels, and on four. And education for both groups is definitely needed. (The potential for damage to others, however, is far greater when such poor driving is perpetrated by those in motorised transport.)

And despite your claims that cyclists don’t pay road taxes, many (perhaps a majority of adult cyclists?) also own cars & hence pay said taxes. They also subject the roading infrastructure to considerably less wear & tear than motor vehicles do.

Unfortunately I fear that you are not alone in your attitude to those with whom you share the road, & who have both a right and a requirement to be on it. (Cyclists aren’t supposed to be on the pavement – apart from dedicated shared spaces – although it would be a darn sight safer there in some cases.) Coming to work this morning I entered a roundabout, clearly signalling my intent to turn right. I wear high-visibility gear, my lights work, and the intersection was clear ahead when I entered it. This didn’t stop a woman in a van from speeding into the roundabout ahead of me, from the left; she had no intention of stopping & the only things that saved me a trip to A & E (or worse) were my reflexes & brakes.

What’s your take on that, Mr Ware?

social media & pseudoscience Alison Campbell Jan 28

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I quite enjoy Facebook – it’s an enjoyable way to catch up with what friends & family are up to, & I follow a number of good science pages (which provide some nice topics for blogging, from time to time).

But FB can also cause considerable aggravation, through its habit of running ‘targeted’ advertising on one’s page & now, it seems, ‘suggesting’ pages. I mean, I’m very sure I never ‘liked’ this one! Yet it crops up on my feed. Apparently we need to be Earthed ie directly connected with the Earth & its electrical field, in order to avoid the nasty side effects of electromagnetic radiation. It’s as simple as walking barefoot on the grass (I always thought it was a simple pleasure to do that; who’da thunk it was healing as well) – but (as I rather expected) you can buy products to help Earth yourself while inside.

The cynic in me wonders how on earth (no pun intended) those believing in this stuff manage to use the internet to access all this information…

Proponents claim that ‘Earthing’ will

reduce pain and inflammation, think blood and improve blood pressure and flow, improve sleep, reduce stress, increases energy, relieves muscle tension and headaches, lessons [sic] hormonal and menstrual symptoms, dramatically speed healing, reduce or eliminate jet lag, protect the body against potentially harmful electromagnetic fields (EMF’s), accelerates recovery from intense athletic activity.

Won’t their ‘grounding’ block them from the Earth’s magnetic field? Not to mention the effects of being bathed in EM rays while walking outside on the grass. Oh, wait…

And then there’s the spam ads about 55-year-old women looking 27 by using a couple of simple tricks & leaving ‘botox doctors furious’ (oh really?). And ads about green coffee bean extract being the latest weight-loss trick (something that Orac has addressed here, noting, for example, that the ‘evidence’ in support comes from a trial – funded by a company that makes & markets the extract – with just 16 participants & poor statistical treatment of its results).

But the one that spurred me to begin writing this post was an image posted by a FB friend of mine: one which purports to be of a 12-week-old human foetus. (I would have liked to make a comment to the contrary on the page where my friend found it, but couldn’t. Funny how some sites block comments.) I suspect I will shortly be ‘unfriended’, for I added a comment (which was later deleted) to my friend’s post to the effect that the picture was definitely not of a 12-week-old foetus. A foetus of that age is about 30mm long (head-to-rump length) & looks like this.

No surprises that the original image is being circulated by groups opposed to abortion, with a caption that begins

This is what we all looked like at 12 weeks in the womb.

Not sure how telling falsehoods helps strengthen one’s argument.

cloning neandertals – can we? should we? is it true? Alison Campbell Jan 23

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The Telegraph has a story on the possibility of cloning Neanderthals, with the fetching headline: ‘I can create Neanderthal baby, I just need willing woman.’ (You can read the NZ version on Stuff.)

My first thought was ‘eeewww’. (And, as a friend commented, it’s stories like this that get science a bad name.) Once past that rather visceral reaction, various questions popped up: just how feasible is this? Really? Has the researcher given any consideration to the ethical issues such a proposal generates? What about (epi)genetics, ecology & so on? And – for the money – how much of this ‘story’ accurately reflects what the scientist who was interviewed actually said, & how much of it is.. er… down to a combination of poor translation (the original article was in German-language paper Der Spiegel) and journalistic license?

Let’s deal with the last first: it would appear that the Daily Mail is responsible for the form in which this story hit the English-speaking world (oh, why am I not surprised by this?). And indeed, one of the quotes attributed to Harvard geneticist Professor Church strongly suggests the journalist wasn’t paying attention:

The professor claims that he could introduce parts of the Neanderthal genome to human stem cells and clone them to create a foetus that could then be implanted in a woman.

‘Parts’ of the genome would give you a Neanderthal? Implanting a ‘foetus’? Hellooooo.

Prof. Church is very firm that he hasn’t actively sought out volunteers for any potential, very-much-in-the-future surrogacy program. Rather, he was speaking theoretically of what was possible now that the Neanderthal DNA sequence is known. That’s good to hear, but I can’t help thinking that a little forethought might have avoided this whole furore. Science & scientists don’t need this sort of press. And let’s face it, people are more likely to remember the shock! horror! of the original story than they are to recall the subsequent, much less ‘exciting’ correction.

On the ethics front, bringing back an extinct race of humans from the dead (apart from the fact that there’s a little bit of their DNA in most of us) strikes me rather as treating them as objects. And what would be the justification for that? While there’s plenty of evidence that there are individuals around today who view other people in much the same way (ie as objects with no real rights or feelings about what’s happening to them), that is hardly a moral justification for resurrecting the Neanderthals. (And, before someone ever got to the point of cloning, there’d have to be some very serious examination of the ethics of surrogacy in a situation such as this.)

And what of the fact that they’d be brought back to an environment quite different to the one to which natural selection had shaped them? For example, in addition to having a physique (& probably physiology) best suited to cold environments, any cloned Neanderthal would be lactose-intolerant. And, in life, Neanderthals would have had their own microbiome: their own suite of micro-organisms living on and in their bodies and affecting them on a daily basis. For this hypothetical cloned individual, what would be the effect on their health of a microbiome that didn’t ‘match’?

On the genetics front (& Grant or David might like to comment here), there is a big difference between knowing the complete Neanderthal base sequence (or at least, the base sequence derived from a handful of individuals) and having a nuclear genome in a form that can be inserted into an enucleate egg (or stem cell, which was the focus of part of Prof. Church’s discussion with Der Spiegel). Plus, that wouldn’t be enough – the mitochondrial DNA of the egg cell would need to be replaced with Neanderthal mtDNA. Not to mention the effect of epigenetics on expression of those Neanderthal genes.

Yes, definitely some good learning opportunities there. I must try & work some of them into my own classes.

faecal transplants as a treatment for persistent gut infections Alison Campbell Jan 21

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I first heard about faecal transplants while listening to one of Mark Crislip’s podcasts (based on one of his posts at Science-Based Medicine. I always find his work informative & entertaining, though his sarcasm may not be to everyone’s taste). With the title ‘The species in the faeces’ I knew I was going to hear something to do with, well, poo… (You might not want to read what follows while eating lunch.)

Our bodies are home to an enormous number and variety of bacteria, both outside and within. That includes perhaps tens of thousands of species inhabiting the human gut – and contributing more than 50% (by mass) of the end product of that part of our anatomy. Far from being undesirable fellow-travellers, many of the members of those bacterial communities (for each part of the gut has its own assemblage of species) play important roles in things such as our susceptibility to disease. And throwing them out of balance can affect our health quite markedly – for example, antibiotic treatments can have (as a side effect) quite a negative impact on gut function, and one that can last for considerable periods of time. (Crislip remarks that if we were coprophagic, like rabbits, this would be less of a problem, as the normal gut flora would repopulate quite quickly…)

Anyway, while antibiotics can cause diarrhoea in some patients, another (non-food poisoning) cause is an overgrowth of a bacterium called Clostridium difficile. As an infectious-disease physician, Dr Crislip has a strong interest in any potential means of treating this one, as apparently it’s difficult to clear with antibiotics (which of course may well have their own side effects) & has a high relapse rate. In his post, while he was rightly scathing about the various other claims made for faecal transplants, he noted that this particular treatment did have a good ‘cure’ rate for C.difficile infection.

And this week, on Facebook one of the science pages I follow linked to a report of the results of a clinical trial of faecal transplants, in which they performed considerably better than the more conventional antibiotic treatments. They might want to look at alternative delivery routes, though; somehow I find the idea of delivery via a nasogastric tube (or more accurately a naso-ileac tube) a little hard to stomach. (Is the use of synthetic poo likely to overcome this aversion? Not sure.)

Quite apart from the ick factor, there issues that warrant further investigation. Each of us has their own particular assemblage of gut bacteria (& viruses, & protozoa), & Crislip notes that you’d probably get optimum results from a faecal transplant if the donor’s, er, ‘product’ was as close as possible in gut flora to the recipient’s healthy norm. He cautions that use of random donors could have the potential to generate other upsets as the recipient’s immune system reacted to the new lot of bugs.

You can, of course, find all sorts of claims on the internet relating to supposed health benefits of this, that & the other. And so it is for faecal transplants. Faecal transplants as a cure for depression & MS? Frankly, that sounds like a lot of, well, steaming brown stuff.

stem cells, cosmetics – and unexpected consequences Alison Campbell Jan 12

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I’m starting to think about this year’s teaching: what I’m planning, what worked last year & what didn’t, things that need to be revised. One thing I’ll be doing a bit more of is ‘flip teaching’, something that worked well last semester in helping students learn about & gain an understanding of recombinant DNA technologies. I’d already found that for this particular topic, students seemed to gain far more from tutorial-group discussions rather than the lecture itself, and so tried something  a bit different. The class could view a previous lecture recording, plus look at my updated powerpoint slides, before class, and then in the actual lecture I spent about 5 minutes setting the scene, gave them some ‘starters’ for discussion (based on things that had come up in those tuts), and 10 minutes for small-group discussion (which was happy, noisy, & extremely animated) while I circulated & answered questions. Then we came up with a list of ideas & topics generated by those groups, & the discussion began. It was interesting & stimulating & fun – well, that was my impression & the class  feedback suggested that the students found it extremely valuable. Which is great as that was my hope & intention in setting things up that way.

Anyway, one of the topics was stem cells (something I blogged about quite a while ago now), & we talked quite a bit around things like ethics, as well as the practicalities. And the potential risks. Reviewing this particular class, I was reminded of a recent Scientific American article about an unexpected and undesirable outcome of a cosmetic use of stem cells.

Now, stem cells are in the news periodically, often in relation to desperately-ill people who are willing to try just about anything in the hope of achieving a cure. And certainly there is ongoing research into the use of stem cells for things like motor neurone disease, for example. However, the US Food & Drug Administration has so far approved just one stem cell product: the use of cells derived from umbilical cord blood as a treatment for leukaemia.

But cosmetics? Well, yes. Apparently there are quite a few cosmetic uses of stem cells out there – in fact, I’d previously come across the promotion of extract of apple stem cells as a skin rejuvenation treatment. (They are said to come from a strain of apples where the fruit keeps very well & doesn’t wither… And I must say, it was a pleasant surprise to see the Daily Mail being reasonably sceptical of this one.) But these uses can have rather unexpected consequences.

In this particular case, back in 2009 a woman had undergone a ‘facelift’ that used her own adult stem cells taken from abdominal fat: specifically, mesenchymal stem cells, which can differentiate into the cells that make up fat, bone, & cartilage. These cells had been cultured & then injected into the woman’s face, particularly the area around her eyes, where they would supposedly stimulate growth of new cells and help repair existing tissues. The process went well, but 3 months later she consulted another cosmetic surgeon, telling him that it hurt to open one eye – & that when she did, she heard a strange clicking noise. The surgeon ended up removing pieces of bone from her eyelid and the tissue around her eye – these were the source of the clicking noise, & they’d also scratched the surface of her eye.

Why bone? Because during the original treatment the doctor had injected a dermal filler, routinely used to reduce wrinkles by ‘filling’ them in. (The cynic in me wonders whether any perceived improvements in appearance were due to this, rather than the action of stem cells.) These fillers contain a substance called calcium hydroxylapatite – used by cell biologists to trigger differentiation of mesenchymal stem cells into bone; in other words, this outcome could have been predicted.

So, unregulated treatments may well pose risks for consumers. In addition, they may also indirectly affect research into possible applications of stem cells in therapies for actual, serious illness (in contrast to what one could describe as ‘vanity’ treatments), as the Scientific American article concludes:

Beyond the considerable risks to consumers, unapproved stem cell treatments also threaten the progress of basic research and clinical trials needed to establish safe stem cell therapies for serious illnesses. By harvesting stem cells, subsequently nourishing them in the lab and transplanting them back inside the human body, scientists hope to improve treatment for a variety of medical conditions, including heart failure, neurodegenerative disorders like Parkinson’s, and spinal cord injuries—essentially any condition in which the body needs new cells and tissues. Researchers are investigating many stem cell therapies in ongoing, carefully controlled clinical trials. Some of the principal questions entail which of the many kinds of stem cells to use; how to safely deliver stem cells to patients without stimulating tumors or the growth of unwanted tissues; and how to prevent the immune system from attacking stem cells provided by a donor. Securing funding for such research becomes all the more difficult if shortcuts taken by private clinics and cosmetic manufacturers – and the subsequent botched procedures and unanticipated consequences – imprint a stigma on stem cells.

I’ll be giving this article to my 2013 class to read. It should provoke some interesting discussion.

 

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