SciBlogs

Archive July 2012

sharks don’t get cancer? Alison Campbell Jul 31

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It turns out that if you thought that foetal lamb cells as a treatment for autism (& a range of other disorders & illnesses) was the pinnacle (or should that be ‘the depths’?) of silliness, you’d be wrong. Dr Huertgen has competition.

It was previously believed that sheep were the best donor animals because of their five or six embryos.

Yes, let’s just consider that for a moment. A ‘therapy’ based on tissue from near-term foetal lambs will of necessity require the death of those lambs, & probably also the mother. I wonder if the idea went anywhere near an animal ethics committee?

However, with the results of recent research, shark embryo cells seem to be vastly superior to sheep embryo cells, in particular the blue shark (Cacharius glaucus) found only in the waters of the Pacific Ocean. (It is important to note that sharks are hunted and killed daily, and the embryonic sac is normally thrown away as worthless.)

Using an otherwise wasted byproduct – that sounds really good, doesn’t it? No, it doesn’t. Finding another use for bits of sharks that might otherwise be thrown away, seems to be simply adding to the pressure on these top predators. And the ongoing decline in shark population numbers can have much broader ecological implications.

The shark has a perfect immune system in that it is free from cancer and has no contagious diseases.

While Orac’s already discussed this** at some length, I thought I’d look again at this idea as it’s one that I hear relatively often from students. The idea that sharks don’t get cancer seems to be an enormously popular myth, but that’s all it is, a myth. Until recently there was little research on tumour development in sharks, but where that work’s been done, tumours have been found. Unfortunately it’s a myth that’s probably only increased the over-fishing of sharks, as various preparations of shark cartilage are on offer to help people fight off cancer.

As for the bit about “no contagious diseases” – again, completely untrue. Sharks are subject to a range of bacterial & viral infections, plus parasites, & in fact exposure to those disease agents has played a large role in the evolution of the vertebrate immune system.

It has so far proven impossible to produce cancer cells in the blue shark and this animal also will never accept the HIV virus, for example.

SInce HIV is a virus that infects primates, this is hardly surprising, nor is it a rationale to use shark tissues to attempt a ‘cure’.

Additionally the blue (and other) sharks have circulating antibodies as immunoglobulin already circulating in their blood. Equally important, the cells used in Live Cell Therapy should be from a specie which has a comparable pregnancy time to the human, such as the blue shark.

Methinks someone doesn’t really have a good handle on the immune system. Immunoglobulins – we have them too!

And why, oh why, should the animal’s gestation period have anything to do with it?

Oh wait, it sounds sort of science-y, right? And of course, it makes this ‘treatment’ sound so much better than, say, that ovine example we looked at. That is, If it’s possible for one pile of of bovine excrement to look, sound or smell better than another…

 

** I really don’t know how he can bear to read so much of this material, although I suppose being a small plexiglas box full of blinking lights*** probably helps.

*** Oracian in-joke.

foetal lamb cells for autism? baaaah! Alison Campbell Jul 29

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Orac posts a fair bit on various quack ‘treatments’ – some, like the use of so-called Miracle Mineral Solution (aka industrial bleach) for just about anything that ails you – are quite dreadful in their potential to do harm. (MMS’s latest outing was as a ‘treatment’ for autism – used as an enema!) One recent post caught my eye as I was looking for new ‘critical thinking’ material for the Scholarship Biology preparation days that I run, & I ended up sharing it with teachers at the teachers’ evening we ran last Friday.

Behold the wonder that is ‘Fresh Cell Therapy’!

Fresh Cell Therapy [is] a biological treatment by which specially selected fresh or live cells or cell extracts of donor animals, usually sheep, are injected into the human body for treatment of various ailments or rejuvenation purpose.

The procedure uses fresh cells from the fetus of a lamb…

… and it’s described (in this news story) as “the mother of all stem cell treatments” by Dr Huertgen, the director of the German clinic offering this ‘therapy’ to those desperate enough, or gullible enough to pay for it (& it will cost them – around $15,000 per procedure, including flights & accommodation). For that price it had better be good! So let’s have a look at what’s involved, according to Dr Huertgen.

The immune system of the body serves as the “communicator” which delivers the cells to the organs and tissues that need rebuilding.

This is unlikely in the extreme. All that’s going to happen is that the immune system of the injected individual will recognise those lamb cells as what they are, foreign tissue, & destroy the lot of them.

Unlike autologous stem cell transplant, in which blood-forming stem cells are removed, stored, and later given back to the same person, fresh cell therapy is non-invasive and is only injected to the body.

This really cracked the teachers up (and I nearly spilled my tea on the keyboard when I first saw it) – sticking a needle in someone is ‘non-invasive’?

As one of Orac’s commenters noted, one of the strange things about all this is that a subset of those who claim that vaccines cause autism, include in their list of Bad Ingredients the fact that said vaccines supposedly contain animal cells. Yet here we have a ‘treatment’ that involves deliberate injections of animal cells. Sorry, can’t get my head around that one.

It is also organ-specific, unlike most stem cell treatments. They inject cells that are harvested in a specific organ that will help rebuild the same organ of the patient.

Always supposing the patient’s immune system somehow failed to destroy the lamb cells, how on earth would they know where to deliver them? And how? Yet Dr Huertgen describes fresh cell therapy as “the only cell therapy that is able to choose the [specific] organ” in need of rebuilding.

More seriously: when ‘treating’ children with autism, he is presumably using the brains of foetal lambs. Sheep carry scrapie. Prions – the agents of scrapie infection (& of other transmissible spongiform encephalopathies) – don’t appear to be destroyed by an infected animal’s immune system. Has this man really thought about what he’s doing?

I rather think the answer is ‘no’.

‘esoteric’ – you keep using that word… Alison Campbell Jul 23

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…. and in the immortal words of Inigo Montoya: “I do  not think it means what you think it means.”

At least, that’s what I thought when I came across this website (courtesy of PZ Myers & also discussed on various Australian media sites, although I’m not sure that I’m grateful as now I need to rinse my brain).

For Universal Medicine & its founder claim to make one feel better through a range of ‘sacred esoteric healing’ treatments, including: ‘esoteric’ massage, ‘esoteric’ chakra-puncture, ‘esoteric’ connective tissue therapy, & so on. After reading that list I had to go & refresh my memory of the definition of ‘esoteric’: designed for, or understood by, the specially initiated alone; limited to a small circle.

Yet massage is surely just that, massage, & chakra-puncture seems to be acupuncture by another name. A lot of people around the world will know something about them, so they can hardly be ‘esoteric’ in the dictionary sense. Maybe it’s just a nice-sounding word? But no, Universal Medicine uses it in a different sense.

As for the connective tissue therapy:

What is Connective Tissue Therapy?

Essentially, it is a deeply stilling form of manual therapy that allows the body to re-instate its deepest form of energetic status. This is achieved by allowing the pulse of the Lymphatic System to symbiotically correspond with the body’s own ensheathing web – the connective tissue. When the two combine, under a specific pulse activated by the practitioner, the body begins to respond and thus there is a certain flow in its deepest and most natural innate state.

Last time I looked, the lymphatic system doesn’t have a pulse, & goodness knows how that system is supposed to ‘combine’ with the collagen fibres that comprise much of our connective tissue. Word salad, yes; energy woo, yes; vaguely science-y sounding, yes: I’m well on the way to completing my pseudoscience bingo card already! UM’s ‘esoteric’ connective tissue therapy is claimed to be supported by research evidence, However, I see that this is ‘published’ in-house & has not been subject to any external peer-review process. It involved 50 clients in a series of sessions that included ‘craniosacral therapy‘, & the effectiveness of this was ‘measured’ in the following way:

The Craniosacral Pulse was measured using gentle hand techniques at the skull to measure the time of expansion and relation of the cranio-plates in the skull, as the cranio-sacral fluid moves in and out of the skull in a cyclic rhythm.

In other words, a purely subjective ‘measurement’ of a non-existent phenomenon: the plates that make up the cranium’s bony dome are not normally free to move against each other once individuals reach adulthood, nor is there independent evidence that the cerebrospinal fluid actually pulses in this manner. And it’s ‘supported’ by anecdotal evidence of well-being from the clients.

Research. That word – I do not think it means what you think it means.

 

moss s*x and springtails Alison Campbell Jul 22

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Sexual reproduction in flowering plants is often mediated by the birds & the bees (& other animal agents), but up until now the life cycle has appeared much simpler in plants like the mosses. Until fairly recently it was generally accepted that moss sex was a case of ‘just add water’: this released sperm from the male plants which could then swim in the film of water to where the female plants held their eggs. Of necessity this would mean that sperm dispersal could be only over quite short distances, of a few centimetres at most.

However, Todd Rosensteil and his colleagues (2012) decided to confirm the hypothesis that arthropods known as springtails could be involved in transferring sperm between male and female mosses. (Springtails and mosses evolved at the same time, during the Ordovician period.) They posed a number of questions: were springtails really acting as go-betweens in moss sex? If the answer was ‘yes’, how did the moss plants attract their little helpers? And, were the springtails important only if there was not much water around?

Using a common – & cosmopolitan – moss called Ceratodon purpureus, Rosenstiel and his colleagues first determined that female C.purpureus plants emit a significantly greater number of volatile organic chemicals (VOCs), which could act as signals to springtails, than male mosses do. They then carried out a number of experiments.

First of all, they gave springtails a choice between male and female moss plants – the tiny arthropods were much more likely to go for the female plants. (However, it’s not yet clear why the springtails respond positively to this signal: do they get some sort of a food reward?) The same was true when the springtails were given no visual cues & were simply offered a choice between male and female moss VOC samples.

Then, they set up a series of ‘microcosms’ – miniature ecosystems containing moss plants, and where the presence of water and springtails could be manipulated. This time the research team used both C.purpureus and another moss species, Bryum argenteum, in which earlier work had shown that springtails were implicated in spreading sperm around. Some of their microcosms had only the mosses. Others were sprayed with water but had no springtails, or had springtails but no water spray. And some had both springtails and water. The results were fascinating.

When a female moss plant’s egg is fertilised, the resultant zygote grows into a thin brown stalk with a capsule of spores on top: this structure is called a sporophyte. Unsurprisingly, mosses in the absence of both water and springtails produced very few sporophytes indeed. Both the ‘springtail treatment’ and spraying the mosses with water caused a marked increase in fertilisation, as measured by the number of sporophytes produced. But combining springtails and the water treatment saw the number of sporophytes more than double, compared to each treatment on its own. The researchers commented that

[t]hese results highlight the substantial role of microarthropods in facilitating fertilisation in mosses, presumably through enhanced sperm transport.

So maybe we really are looking at something akin to the relationship between flowering plants and their pollinators. And, given the potential antiquity of this arrangement,

it is important to consider the potential role that a plant-pollinator-like relationship may have had in shaping the evolutionary ecology of moss mating systems.

I will definitely be changing the ‘additional reading’ list for my first-years!

 

T.N.Rosenstiel, E.E.Shortlidge, A.N.Melnychenko, J.F.Pankow & S.M. Eppley (2012) Sex-specific volatile compounts influence microarthropod-mediated fertilisation of moss. Nature published on-line 18 July 2012, doi: 10.1038/nature11330

first supertrees – now super domes Alison Campbell Jul 19

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singapore conservatory dome.jpgAfter goggling (a mixture of gobsmacked & ogling) the supertrees, our little party of escapees from the day’s official IBO program made our way into the Flower Dome, the first of the two great conservatories in Singapore’s Gardens in the Bay. Cue more ‘oh, wow!’ moments as the scale of the building became apparent – this is what it looks like once you’re through the doors (& into the wondrous coolness of the huge space):

singapore - entrance to flower dome.jpg

This dome contains gardens, or garden collections, from around the world, including the displays of flowers that give it its name. I was fascinated by the visual juxtaposition of the gardens with the almost futuristic cityscape beyond the conservatory walls.

singapore - flower dome & cityscape.jpg

singapore - flower dome hibiscus.jpg

From some perspectives the dome’s interior gives the impression of being heavily forested, & it’s at this point I had to keep reminding myself that none of this was here even 4 years ago: all the mature trees were brought onto the site from elsewhere…

singapore - flower dome forest look.jpg

… including a 1000-year-old olive tree. We could only guess at the huge amount of work (by goodness knows how many gardeners) to get all these plants established.

singapore - flower dome with olive tree.jpg

There’s also a wonderful collection of xerophytes: plants adapted to life in a dry environment. The plants in the following photo show a range of interesting adaptations related to this lifestyle.

singapore - xerophytes.jpgAnd scattered through the dome is a range of artwork, including this lovely botanically-based eagle, developed from the roots of a tree. (I am always amazed at how some people are able to ‘see’ the form within something, and work to bring it forth.)

singapore - flower dome eagle.jpg

 

singapore’s stupendous supertrees Alison Campbell Jul 16

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I’ve just got back from the 2011 International Biology Olympiad. Our team did well – Richard Chou received a silver medal; Sumin Yoon & Evelyn Qian won bronzes, & Eddie McTaggart was awarded a Certificate of Merit. So well done, all round!

It was a testing time for our students, who were competing against the best senior school biology students in the world. Mind you, it wasn’t exactly a holiday for the jury members accompanying them, who put in some extremely long hours as the demanding practical and theory exams were finalised. But both students and jury members had time for relaxation on their schedules. In one of those ‘off-duty’ periods, along with 3 colleagues I caught first a bus & then a train to visit Singapore’s spectacular new Gardens by the Bay. Around every corner was a new ‘oh, wow!’ moment, and we collectively took an album full of photos. Like this one:

  singapore supertrees.jpg

These are some of the ‘supertrees’ – a grove of metal and concrete ‘trees’ betwen 30 & 50m high that dominate the park’s skyline (& put on a fine show at night, when they contribute to the light show along the downtown waterfront). They’re living gardens, clothed in vertical gardens & with a sky-walk running among them. At the top of each ‘tree’ is a bank of solar panels, harvesting sunlight to power the park’s systems; they also include a system to collect and distribute rainwater, & in addition act as exhaust and cooling systems for the huge domed conservatories nearby.

singapore supertrees & dome.jpg

There are two such domes: one houses a collection of gardens from different regions – including a 1,000 years-old olive tree. This & all the other mature (& adolescent) trees in the gardens were brought in from around the world (at goodness knows what expense!) The other is home to an artificial ‘mountain’ that provides a cloud forest environment to an enormous number of different plant species and includes a plunging 30m waterfall. It also provides some wonderful views, including another perspective on the supertrees that to me only serves to emphasise their other-worldliness:

singapore supertrees from dome.jpg

a letter from exotic places Alison Campbell Jul 10

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Once again my good intentions to get back into a more regular blogging cycle have been stymied – although this time the reasons are all good.

For I am in Singapore, at the 2012 International Biology Olympiad. Fifty-nine different countries have sent students to compete in this prestigious competition, supported by senior academics & teachers. Having met a fair number of them during today’s opening ceremony (attended by the President of Singapore) & the subsequent luncheon, I can say that it’s a real privilege to work with the world’s best biology students – who are going to become tomorrow’s leaders in the field.

It was also quite inspirational to hear the extremely high value that Singapore places on its people’s education. As the host for the ceremonies remarked, “we don’t have much in the way of natural resources, but we do have our people’ – & with those people this small island state has made itself an intellectual & economic powerhouse. And a generous & welcoming host for this year’s Olympiad.

more on active learning in the biology classroom Alison Campbell Jul 03

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This is a piece I first wrote for Talkingteaching :-)

Yesterday I was up in Auckland at Scicon (the national secondary science teachers’ conference. There’ve been some great presentations, including a lovely on on bioluminescence by fellow sciblogger Siouxsie Wiles (did you know that our very own NZ glow worms mate for hours & then die of exhaustion? Or that 4500 people die of tuberculosis every day? Yes, there really is a link to bioluminescence there.). I gave mine in the morning & could then focus on enjoying everything else that’s going on.

My talk was about the ‘flip teaching’ idea that I was introduced to by Kevin Gould, which I’ve written about previously. Actually it wasn’t really a talk, as I simply gave a bit of background & a summary of some of the recent research, & then asked participants to do the activity themselves. At which point everyone got involved & the chatter started – it was hard to get them to stop at the end! But we managed a show-&-tell & some great discussion before our time was up.

One of the things people really picked up on was something I really hadn’t thought much about: using it to underpin development of students’ writing skills. That’s in addition to conceptualising, discussing, & drawing their organism: there are also things like annotating that diagram, & writing descriptive paragraphs about the various ideas they’ve used. Really integrated learning!

 

more on active learning in the biology classroom Alison Campbell Jul 03

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This is a piece I first wrote for Talkingteaching :-)

Yesterday I was up in Auckland at Scicon (the national secondary science teachers’ conference. There’ve been some great presentations, including a lovely on on bioluminescence by fellow sciblogger Siouxsie Wiles (did you know that our very own NZ glow worms mate for hours & then die of exhaustion? Or that 4500 people die of tuberculosis every day? Yes, there really is a link to bioluminescence there.). I gave mine in the morning & could then focus on enjoying everything else that’s going on.

My talk was about the ‘flip teaching’ idea that I was introduced to by Kevin Gould, which I’ve written about previously. Actually it wasn’t really a talk, as I simply gave a bit of background & a summary of some of the recent research, & then asked participants to do the activity themselves. At which point everyone got involved & the chatter started – it was hard to get them to stop at the end! But we managed a show-&-tell & some great discussion before our time was up.

One of the things people really picked up on was something I really hadn’t thought much about: using it to underpin development of students’ writing skills. That’s in addition to conceptualising, discussing, & drawing their organism: there are also things like annotating that diagram, & writing descriptive paragraphs about the various ideas they’ve used. Really integrated learning!

 

divergent views on the importance of critical thinking Alison Campbell Jul 02

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Regular readers will know that I spend quite a bit of time writing about critical thinking: what it is, why it’s important, how to develop the relevant skills in our students. In fact, I tell my own students that one of the most important things they’ll gain from their time at uni is the ability to think independently and critically.

So I was rather gobsmacked to read one of Orac’s recent posts, about the (rather scary) proposed election platform of the Texas Republican Party. Quite a bit of the content is surely cause for some concern, & anti-science in so many ways (anti-evolution & anti-vaccine, to name a couple), but this particular bit caught my eye:

We oppose the teaching of Higher Order Thinking Skills (HOTS) (values clarification), critical thinking skills and similar programs that are simply a relabeling of Outcome-Based Education (OBE) (mastery learning) which focus on behavior modification and have the purpose of challenging the student’s fixed beliefs and undermining parental authority.

From the perspective of science, & science teaching, this is really concerning, on several grounds. For starters, science is predicated on critical thinking: it’s what scientists do. Any proposed action/intent to reduce students’ acquisition of such a key skill-set is not at all desirable. In addition, all good teachers will challenge their students’ “fixed beliefs” from time to time – some very meaningful learning can result from such challenges. (I do wonder if this phrase isn’t specifically aimed at the teaching of evolution, given the fears in some quarters that this will challenges religious belief. The same is true for “undermining parental authority”.)

And of course, there’s the flow-on effect – Texas is a major purchaser of science textbooks & decisions there often have a flow-on effect in terms of what’s available in other states. So it would not be students in only a single state that would suffer, if a proposal such as this should ever gain traction.

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