Archive for February, 2012

Feb 10 2012

Another Brain Stem Cell Study

Published by under Neuroscience

I have been casually tracking stem cell research over the years, especially for neurological indications, primarily to have a feel for where we are in the course of research. It takes years to develop a new therapy, and stem cell therapy is a tricky new technology. Right now we are in the post-hype era – the peak of media hype seems to have passed (probably just a short-attention-span effect) while the hard research continues to grind along. We are also in the snake-oil phase where heartless con-artists are capitalizing on the premature hype to sell fake stem cell treatments to desperate patients.

Meanwhile I want to know how the real research is progressing. It seems we are mostly in the animal trial phase and at the cusp of human trials for the most plausible applications. We may see human applications within 5 years for some applications. Heart failure and macular degeneration, for example, seem to be closest.

Some neurological applications are likely to also be among the early applications. Those applications which are likely to cross the finish line of routine clinical use are those in which we simply need to squirt stem cells into some tissue or body cavity and then the stem cells will function as raw material for regeneration or healing. Heart cells work well because they normally will start beating in time along with their fellow heart cells.

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Feb 09 2012

A Living Mammoth?

Published by under Skepticism

This story is a classic of cryptozoology. A paranormal researcher claims to have come into possession of a video of an alleged living woolly mammoth. Immediately, skeptical red flags should be flying, but let’s take a deep breath and look more closely at the story.

First, it is always good to go into any exploration or investigation with an open but informed mind. Too often people equate “open mind” with a mind empty of all relevant information. Before scientists embark on a new line of research they typically will first see everything that has already been researched on the topic, to see if the idea has already been answered, or if it is even plausible.

In this case we may or may not be able to come up with a definitive answer, but we can start by considering the plausibility of the claim (what some might call “armchair skepticism”, but should not be denigrated). Mammoths largely died out about 10,000 years ago. Recent fossil evidence suggests that a population of dwarf woolly mammoths survived on Wrangel island, off the coast of Siberia, up until as recently at 4,000 years ago. It is not entirely implausible that a small population of even large mammals could survive in the remote wilderness without being detected.

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Feb 07 2012

3D Printing

Published by under Skepticism,Technology

This is one of those emerging technologies that has the potential to be a game changer – the ability to print three-dimensional objects. A recent news story brought to my attention how far this technology has come so far. Belgium surgeons have recently (this past June, although they just announced it) implanted an artificial jaw into an 83 year old woman. The jaw is made from titanium and was created with a 3-D printing process.

The process of creating the jaw involved “printing” thin 2-D layers and then combining them:

“It used a laser beam to melt successive thin layers of titanium powder together to build the part.

“This was repeated with each cross section melted to the previous layer. It took 33 layers to build 1mm of height, so you can imagine there were many thousand layers necessary to build this jawbone.”

There are multiple advantages to this technology over other forms of crafting 3-D objects. Digital design is nothing new, but of course this process benefits from the ability to design a part with software, make it perfect, and then craft it. For surgically implantable parts this also allows for the use of CT scan or MRI scans to precisely design parts of the exactly correct size and shape. Using the layering process also allows for complex internal structure, like grooves and holes, that some methods cannot create.

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Feb 06 2012

Morgellons – Creating a New Disease

Recently the Centers for Disease Control published the results of a fairly comprehensive study of what some call Morgellons disease. This is a controversial entity  – not so much within scientific circles, but because of an active group of proponents. The claims that Morgellons is a distinct pathophysiological disease, and the recent study, raise some basic questions: How do we establish that a diagnosis really exists? How are psychogenic disorders diagnosed?  These are serious and complex questions in medicine.

First we have to recognize that the term “diagnosis” refers to various types of entities. A diagnosis is a label that we use to describe the signs, symptoms, natural history, and possible biological causes that we observe in more than one patient. There has to be some recurrent pattern, and that is what we are labeling. The term “disease” is similar, but more specific, referring to a specific pathophysiological entity – a specific malfunction or dysfunction of some biological process. For example, myasthenia gravis is a specific disease in which the immune system creates antibodies that attack the acetylcholine receptors on muscle cells, inhibiting muscle contraction and causing weakness and fatigue. In fact MG can be divided into several subtypes, depending on the presence and type of antibodies detected. It is a very specific pathophysiological entity, and diagnosis and treatment flows from our understanding of the disease process.

We do not always understand the details of what causes a specific medical entity, however. Often we start with a syndrome – a constellation of signs, symptoms, and natural history that occurs in more than one patient. It then may take years or decades to sort out the cause or causes of the syndrome, subtypes, prognosis and treatments. Knowledge of the cause is also not black or white. There are layers of depth and detail to our knowledge of various syndromes and diseases. We may know that a disease is an infectious disease, but not know much about the organism. Or we may know what body tissue is being affected and how that results in the symptoms, but not what is causing the damage.

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Feb 02 2012

American Headache Society Recommends Placebos for Migraine

This is yet another installment in my series on how so-called “alternative” medicine thrives under a double standard – a bizarro world where the rules of science and logic are suspended in favor of uncritical promotion. The American Headache Society (AHS) just sent out a press release endorsing acupuncture for migraine headaches. They write:

Mt. Royal, NJ (February 1, 2012) – When it comes to treating migraine, so-called “sham” acupuncture (where needles are inserted only to a superficial depth in the skin and not in specific sites) and traditional acupuncture where needles are inserted in specific sites, both are effective, according to the American Headache Society (AHS).

Citing publicity surrounding a recent Canadian study comparing the effectiveness of the two types of acupuncture, David W. Dodick, MD, AHS president, said both types of acupuncture, particularly when electrical stimulation is involved, may work to release endorphins that are important in controlling signals of pain and inflammation.

“How much of a benefit sham acupuncture can have on the release of these chemicals is unclear,” he said. “This suggests the benefits of treatment may not depend on the exact technique of acupuncture and needle positioning.”

Studies show that sham acupuncture is as effective as true acupuncture, and Dr. Dodick concludes from this that both work. The proper scientific interpretation of this result is that the treatment (acupuncture) is no different than placebo (sham acupuncture) and therefore has only a placebo effect. Only in CAM world can you take a negative result and then spin it into a positive result like this. Science is all about controlling for variables, and when you control for the variable of acupuncture (inserting needles into acupuncture points) it does not work.

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