Sound Science Notebook: Crash Course in the Embryonic Stem Controversy (and other News of Note)
Talk about the blind leading the blind: G. W. (Global Wreckingball) Bush has lead the GOP in a series of sweeping moves impacting the global environment, national security, and world stability. In the world of the sane (or at least functionally insane), all of these decisions, from the Kyoto Protocol to the push for the missile defense shield and the energy policy would require at least a rudimentary grasp of the science involved. Not so in Bush world - a place that resembles Flatland - a fictional realm where only two-dimensions exist and the Flatlanders scurry about oblivious to the world of three-dimensions. Unfortunately, we live in a complex world where soon an understanding of four or even five or six dimensions may be desirable.
No matter how hard Bush et al. tug backwards on the world’s coattails, this is the 21st century, and civilization will keep moving forward - with or without its political dinosaurs in tow. As Democrats, we must be committed to staying well-armed with bonafide “sound science” - not the Flatland version pandered by Bush. To supply our readers with background information on scientific and technological issues related to policy, we will present regular (God willin’ and the creek don’t rise) installments of “Dems Digest.” Any questions or topics that you may have on these issues, please write us at email@example.com.
The Burning Question Hanging over Stem Cell Research: When Does the Life of an Individual Technically Begin?
Although embryonic stem cells are at the focus of one of the most heated debates ever, a large percentage of people are still not clear on all the scientific facts (eg. - just what the heck are stem cells?). Here is a crash course:
When a mammalian egg is fertilized, within hours it begins to cleave, which means it begins a series of critical cell divisions. This early cleavage produces a hollow ball called a blastula, which is implanted in the uterine wall around day six following fertilization. The outer wall of the blastula is a single layer of cells while contained within this ball (rather like a yoke within a hollow egg) is a tiny solid blob of cells called a blastocyst.
The blastocyst is the source of embryonic stem cells. These are cells that have not yet “received their orders” as to what type of tissue they will become and thus are considered “undifferentiated” (a term you have probably heard in stem cell discussions). Embryonic stem cells can ultimately become nearly any type of tissue - liver, bone, pancreatic, blood, etc. They are, in essence, the “raw clay” of the body.
Although for most folks, the term “embryo” conjures up a picture of a little being with at least a rudimentary resemblance to a fetus, the blastula/ blastocyst stage bears no such resemblance. In fact, human blastocysts are all but indistinguishable from the blastocysts of chickens, lizards, antelope, mice, or any other vertebrates.
After the blastocyst stage, the cells continue to divide and form into distinct layers (called the endoderm, mesoderm, and ectoderm) that will give rise to the various systems. This process, which occurs around the second week following fertilization, is called gastrulation and the layered body it forms is called a gastrula.
The argument that life begins at fertilization - the chief argument of those against ES use - has some major flaws in reasoning. First, Dolly (the famous sheep created through cloning a few years back) proved that life can begin in the absence of fertilization. Dolly was generated by transferring the nucleus from one cell into the hollowed out nucleus of an egg cell (ovum), which was then implanted in the womb of a surrogate mother sheep.
Another major stumbling block to the “life begins at fertilization” argument is the “problem” of twins. The splitting of an embryo to create twins may occur during gastrulation - which occurs many days after fertilization. So is the second child less alive because he or she did not arise directly from fertilization? Because of the twinning issue, many bioethicists believe an embryo cannot be considered an individual human being until after gastrulation has occurred. This definition is considered especially sound because it can be applied to embryos created with or without fertilization. Thus, according to this definition, before gastrulation, an embryo is, of course, alive, but more in the sense that eggs and sperm are alive - i.e., they are cells but they are not independent organisms.
Companies such as Advanced Cell Technologies in Worcester, Mass. which try to skirt the “life begins at fertilization” issue by creating embryos by cloning are simply copping out, because, technically, the entity in question remains the same - a tiny basketball of undifferentiated cells. By creating a clear and acceptable definition of what constitutes an independent individual, other issues may be much more open to compromise. For example, treatments like the “morning after pill” might be considered more acceptable to even the most conservative people under this definition. In addition, in the future, advanced medical testing procedures could be developed that are able to detect pregnancy within the first week or so after conception. Procedures which terminate pregnancy before gastrulation is completed might even be found acceptable to those who would in any other instance oppose abortion.
Meanwhile, as we debate the issue, we are already starting to lose some of our best researchers. Roger Pederson of the University of California at San Francisco, who is a pioneer in ES research has become so daunted by the uncertain political climate in the US that he is leaving the country to head a research facility in Britain. For a visual perspeective on where the blastocyst and gastrulation stages fall in development, check out http://pregnancy.about.com/gi/dynamic/offsite.htm?site=http%3A%2F%2Fwww.visembryo.com
Yet Another Wonder Drug Not So Wonderful Afterall
The anticancer drug Gleevec was lavishly touted as a possible cure/preventor of chronic myeloid leukemia. After an initial period of clinical trials, the maker, Novartis, rushed the drug to market, dollar signs no doubt gleaming in the execs’ eyes. The company managed to get the FDA to approve Gleevec in record time based only on early test results. No one in marketing or Washington (what’s the difference?) waited around long enough to find out that after a few months, most of the patients treated with Gleevec relapsed. Why? Because the drug quickly induces resistance in the cancer cells. This is because Gleevec, which acts by blocking certain proteins associated with the cancer, induced self-protective mutations in the cancer cells.
There are three very troubling things about this development. First of all, because the drug was touted as all but a cure for CML, thousands of CML victims were given false hope, soon replaced by crushing disappointment. Drug companies never factor the possibility of inflicting emotional pain on consumers into their promotional campaigns because to do so would detract from their license to make bloated promises. But, maybe it’s time they are held accountable for the unnecessary stress so often caused by their rush to market.
As an abstactor, I am appalled by the discrepancy between how the media portrays “an amazing medical breakthrough” and how this “breakthrough” was actually described in a research article in a professional journal. The journal article may describe the results of a study as “promising,” with treatments possibly coming out of the work years down the road - MAYBE. Then, a week or two later, a talking head on the nightly news announces the same finding as a veritable cure that could be on pharmacy shelves any day. Researchers find this misrepresentation maddening, at the least. At the worst, it leads to unrealistic expectations and pressures to push through research that cuts corners.
Second, once Novartis started playing up the wonders of Gleevec, other researchers working on drugs based on a similar strategy (protein blocking) went full steam ahead, at the expense of other possible avenues of research. Unfortunately, all of these drugs may have problems similar to Gleevec. Afterall, you are tinkering with one of the body’s own fundamental building blocks, proteins.
Third, because the Bush FDA is blatantly pro-industry, it is likely that similar episodes of muscled-through failures, some with even more harmful consequences than Gleevec, are likely to happen again soon.
Nonstick Coating Found to Contribute to Greenhouse Gases and Ozone Depletion
First, some handy background: Ozone is actually the common-usage term for O3, a molecule which differs from everyday atmospheric oxygen (O2) in that it is composed of three oxygen atoms instead of two. This extra atom makes it more reactive than O2 and thus much less stable (and vulnerable to destruction). There are two familiar forms of ozone: ground level O3, which is a major component of urban smog, and stratospheric O3 which is found in the upper atmosphere. Stratospheric O3 protects Earth from an overdose of damaging ultraviolet radiation and thus is far more vital to our survival than any Star Wars shield.
We all know that CFCs (chlorofluorocarbons) were used in the first generation of aerosol sprays - in our ignorance, we all used them in merry excess (I cringe at the thought of all those cans and cans of deodorant, window cleaner, hairspray, etc!). We also all know that CFCs were found to react in the atmosphere in a way that destroyed stratospheric O3. Unfortunately, in another rush for a quick fix, CFCs were replaced by HCFCs (hydroflurocarbons), a family of compounds which was soon found to create a whole new problem. When the compound breaks down in the atmosphere, it forms the toxic chemical trifluoro-acetic acid, which hangs around indefinitely, thumbing its nose at us, and coming back to haunt us in tainted rain.
Now researchers how found another, unexpected source of CFCs AND trifluoro-acetic acid: the stuff used to make kitchen utensils, ovens, and engine innards “nonstick.” These chemicals may be nonstick, but exposure to heat (the very thing they are sure to be exposed to!) causes them to break down into an cocktail of nasty pollutants.
This discovery highlights the need to restrain the chemical industry, which blithely introduces thousands of new compounds every YEAR, each and every one touted as safe when handled properly. But, no one can predict the behavior of compounds once they are released into the environment. Many chemists say the atmosphere is now stuffed with a growing number of new, exotic compounds formed when chemicals mix and mingle, once released, in ways no one could predict, because such reactions are never taken into account, much less studied. There may be over 200,000 such compounds in the atmosphere in various quantities. But we may never know just how many or what they are because we can only detect the ones we are looking for. Like fingerprints, you can only match them to a suspect’s if you have in your possession both a suspect and fingerprints in a data base. Seems to me that ”sound science” would demand that some sort of database be developed and a list of suspects drawn up.
Move Over, Firestone!
Transense Technologies, a tiny company in Britain, has made the big time! TT recently signed a deal with Michelin, giving the international tire giant exclusive use of TT’s new surface acoustic wave technology (SAW). SAW is an ingenious system that uses a tiny sensor embedded in the tire, which monitors the pressure and temperature of the tire. Tire condition is checked every second or so - often enough to warn of an impending blow out. A few years back, I read in a technical journal about this system. There were various reasons given for its drawbacks to widespread commercial use. Yet, now with lawsuits and bad publicity looming large over the tire industry thanks to the Firestone debacle, isn’t it amazing how quickly an innovative system becomes suddenly practical for “widespread commercial use.”
The car companies are doing the same stonewalling with fuel efficiency for the SUVs, lobbying any improvement right out of the “energy plan” by whining that it would take years and years to achieve such an improvement without sacrificing safety. Well, as one who weekly reads about what’s out there in the realm of technology and science, I am 99.9% sure this is a bald-faced lie. If these companies where ever subjected to some financial pressure, like the tire industry is right now, just watch how fast the technology would be whipped off the shelf (where it has undoubtedly be sitting for years) and implemented!
Missile Interceptors May be Just as Much Threat to Security as Missiles
Several scientists representing the Union of Concerned Scientists and one researcher from MIT (Mass. Institute of Technology) wrote a letter which appeared in July’s issue of “Physics Today.” In it, the scientists expressed concern that the combination of Russia’s aging missile warming system and American missile defense interceptor missiles could a recipe for disaster. They say they believe that the chances of Russia’s system mistaking an interceptor for an incoming missile and launching a defensive attack is unacceptably high.
Logging and Avalanches
A study in Vancouver, British Columbia using advanced digital elevation mapping, data from the Landsat7 Earth-observing satellite, and a multi-criteria evaluation technique has clearly shown that the risk of avalanche is greatly increased in areas where tree cover has been removed through logging, even in areas that had no history of avalanche activity before logging. Avalanches have become a more serious problem in recent years in many areas. (Earth Observation Magazine, July issue).
Native Fish Populations Disappearing from Northeastern Lakes
A study in the Northeast by researchers at State University of New York at Syracuse and the Maine Department of Environmental Protection has shown that intact natural arrays of native fish species have disappeared from most lakes in the northeast. Among the most sensitive of the native fishes are the Salmonids, which include brook and lake trout. These fish require clean, cool, well-oxygenated water. As a result, they are an excellent gauge of pollution and warming temperatures. The study, which sampled 203 lakes and ponds, found that native arrays (the groupings found in an undisturbed environment) of Salmonids had all but disappeared everywhere but in northern Maine. (Northeastern Naturalist vol. 8, no 2 2001)
Next week: Crash Course in Desertification – a Process Now Eating Away at 70% of Earth’s Land