More Things Science Can Do…and It’s Okay!

Per the suggestion of a friend, albeit one that came about three weeks ago, I’ve decided to write an entry about how theories can be supplanted when new ones that make more sense and come with more evidence are proposed. I feel that this draws parallels to the world of politics, where changing your mind based on new information is viewed as “flip-flopping”, whereas if you never change your mind, you are a “strong leader.” The comic Bizzaro did a nice job of illustrating this once, but I can’t find a link to it.

Anyway, as an example of my above point, let’s discuss the Miasma theory of disease, and how it has been supplanted by the germ theory. (Quick definition of theory = “comprises a collection of concepts, including abstractions of observable phenomena expressed as quantifiable properties, together with scientific laws that express relationships between observations of such concepts” (from Wikipedia page on scientific theory.)

The Miasma theory of disease holds that many diseases such as chlamydia, cholera, and even Black Plague were caused by bad/polluted air. (Miasma come from the Greek for “pollution.”) Perhaps one of the best-known instances of the miasma theory being put into large practice is in the cholera outbreaks of the 1850s in London. Until John Snow deduced in 1854 that cholera was being spread via the dirty water in the London slums, the theory that it was being spread by dirty air was the going idea. This idea even made acceptance of Snow’s theory difficult, and prevented sanitary measures from being introduced in a timely fashion.

Florence Nightingale was also a big proponent of miasma theory. That doesn’t discredit her work, however, because due to her strong belief that bad air was causing various infectious diseases, hospitals became more and more sanitary. (And started to smell better!) Others who accepted miasma theory made the connection between dirtiness and disease, but they did not understand that it was the germs in that dirtiness that was actually making people sick.

Enter germ theory. This theory, like many in science, was highly controversial when it was proposed. (Imagine that, controversy in science…) I can definitely see why though: “Wait, so you doctors are telling me that what’s making me sick are these tiny little things that I can’t see and that live inside of me?” Kind of hard to believe, right?

Germ theory is actually much older than Anton van Leeuwenhoek and Louis Pasteur. An ancient Hindu text called the Atharvaveda mentions living agents as the cause of disease. In 36 BC, On Agriculture was published, and in it a warning about locating a home near a swamp, due to minute organisms that can float through the air and cause sickness.

It wasn’t until 1676 that the first of many scientists (van Leeuwenhoek) made the first crucial discovery that would go on to help prove germ theory: observing bacteria under a microscope. That proved the existence of microorganisms. Ignaz Semmelweis contributed to the theory in 1847, by lowering child mortality rates at a Vienna hospital after making doctors wash their hands between autopsies and delivering a child. John Snow, with his observations about cholera, added more evidence. Pasteur, between 1860 and 1864, added even more backing with his evidence against spontaneous generation of bacteria.

Robert Koch, in 1890, really added the final blow against miasma theory, and gave the best weight to germ theory with his postulates. These 4 rules, with following experiments, essentially proved germ theory (and are still used today in the study of new diseases):

1. The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy animals.
2. The microorganism must be isolated from a diseased organism and grown in pure culture.
3. The cultured microorganism should cause disease when introduced into a healthy organism.
4. The microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

Germ theory has supplanted miasma theory because it has been tested many times, has a large body of evidence behind it, and is frankly the more logical explanation. The practice of germ theory has resulted in antibiotics and sterile treatments (thank you Lister), and is now a cornerstone of clinical microbiology. Only delusional people still believe miasma theory.

More Reasons Stem Cells Rock

I have finally decided to post a news article, after much time off! I know you are all excited.

Anyway, researchers led by Dr. Yoram Cohen at Tel Aviv University in Israel have discovered that stem cells derived from bone marrow cells can migrate to diseased areas of the brain, and potentially repair them or halt cell degeneration. These findings have large implications for future treatments of neurodegenerative diseases such as Huntington’s, Alzheimer’s, and Parkinson’s.  This is especially exciting for me, because since my grandmother, who passed away about a month ago, was diagnosed with dementia (no official diagnosis of Alzheimer’s was ever made), I’ve been very interested in research on this disease and others like it.

The first part of the study was to prove that the cells were indeed viable. Using a state-of-the-art nanoparticle system, researchers were able to track the movements of the stem cells, and determined that the cells were indeed migrating to the areas of disease. Dr. Cohen explained, “Cells that go toward a certain position that needs to be rescued are the best indirect proof that they are live and viable. If they can migrate towards the target, they are alive and can read chemical signalling.”

This study also demonstrates the ability of bone marrow stem cells to be transformed in neural-type stem cells. This is good for two reasons: 1) it circumvents the ethical issues presented by using embryonic stem cells, and 2) the cells can be derived directly from the patient they are meant to treat, eliminating the possibility of rejection.

Obviously we are still a long way away from a real-life therapy using this method. We must remember that what works in animals won’t necessarily work in humans (although we sure hope it does!) We do, however, have a new path to explore in terms of treating neurodegenerative disease, and we have more evidence that stem cells are the answer to these diseases.

Long Time No See

Hello everyone! I know it’s been a long time, but that’s what happens when you begin to plan a cross-country move, apparently.

Since I last posted, I’ve completed my move to Syracuse, gotten mostly settled, and begun my second week of work in Dr. Pignoni’s lab. So far most of my job has consisted of flipping flies….and there’s the fire alarm. And it’s pouring. Better go. More later.

….2.5 hours later, here I am again.

As I was saying, most of my work consists of flipping flies, which to the uninitiated means taking all the living flies out of one vial and putting them in a fresh one. This is necessary to keep stocks healthy and can also be done as part of a method to expand stocks. I have done some other things, for example: making +amp plates for plasmid propagation, begun a fly stock expansion that looks like it will take at least a month (the flies are not behaving), helped to organize the lab (the lab itself just moved from MEEI in Boston to Upstate), and a few other miscellaneous things. According to Dr. Pignoni, I will be the “fly tech” once I get comfortable and autonomous in the lab. This is because I have past experience with fruit flies, although I’m hoping that “fly tech” doesn’t mean “no molecular biology” because I really like molecular biology and that’s what the majority of my background is in.

Currently all the PIs in the lab space (there are three, each with their own lab) are on vacay. So we’re having an inter-lab party tomorrow. Which means I need to bake brownies after dinner.

Hopefully I’ll have some biology news or journal articles to discuss soon, now that I’m finally settled and finding some free time at work. But that’s it for now!

Read the New Guidelines

As an addendum to my previous post, here is a link at which you can read the NIH’s new guidelines as well as the reasoning behind the guidelines. The guidelines are relatively easy to read, and they do not require extensive knowledge of biology and technical terms. It’s also quite educational to read how the NIH addressed concerns brought to them during the public comment period.

Final Stem Cell Guidelines Released

Yesterday the NIH released the final guidelines for embryonic stem cell research in the United States. President Obama lifted the previous administration’s restrictions back in February but left it up to the NIH to determine the guidelines for ES research. Note that these guidelines only apply to researchers who hope to recieve federal money.

ES cell research, under the new guidelines, will only be allowed on embryos from fertility clinics that will otherwise be discarded. The donors of such embryos (the parents of the embryo) will be given full informed consent. The rules state that donors must be made aware of other options (such as donating to an infertile woman) before an embryo will be used to create stem cells. Documentation of this whole process will be needed in order for researchers to receive government money.

One potential problem with these guidelines is that older lines that were eligible for federal funding under Bush’s regulations might not be eligible anymore. The NIH has decided to review these lines on a case by case basis, and determine if the stem cells were ethically obtained. If so, these lines will be eligible for government money under the new regulations. The NIH will make a master list of all lines that qualify.

I’m a big fan of the new rules. I believe the guidelines do an excellent job of promoting scientific research while allowing for many ethical issues to be addressed. While those who believe that the process of obtaining ES cells won’t be satisfied, others who do not entirely oppose the research will likely be comforted. The embryos in question will be leftovers from fertility clinics and would be thrown away anyway. This way, the NIH is allowing those embryos to be used for scientific research.

I believe that ES cell research is important for one main reason. If we don’t do the research, we will not know what these cells are capable of. Many who oppose ES cell research believe that the cells hold no promise. Well that might be, but it also might be due to the lack of research being done. Research is quite expensive, and getting private money is incredibly difficult, much more so than getting federal money. The grant process is flawed anyway, but the new availability of federal money will allow researchers to determine with much better accuracy what ES cells are capable of. Until we know this, I don’t believe we can make an ethically responsible, informed decision on using ES cells. If it turns out in 15 years that multiple studies show that ES cells are no better than adult stem cells, then we can stop using the cells.