First Respondent

The article “A Darwinian View of the Hygiene or ‘Old Friends’ Hypothesis” by Graham A.W Rook details the specific outcomes of research that supports the hygiene hypothesis. This hypothesis states that some autoimmune diseases are becoming more prevalent in developed areas due to the lack of exposure to pathogens at a young age. This is due as the lack of pathogen exposure suppresses the natural progression of the immune system and causes a lower degree of immune tolerance. The article “For the Good of the Gut: Can Parasitic Worms Treat Autoimmune Diseases?” by Ferris Jabr elaborates on a specific field of research that is associated with the hygiene hypothesis.  Jabr focuses on the ingestion of parasitic worms to decrease the symptoms associated with gastrointestinal diseases.

In the article by Jabr, it was mentioned that the use of whipworms completely treated the symptoms of a man’s colitis. The article then continues with additional data that supports the use of helminthic therapy without listing any of its’ drawbacks. When reading the article, I initially believed that the whipworm parasite was just a benign worm that probably just hung around in the intestines for a little bit before being passed out without causing any symptoms. However, a quick online search shows that while light infestations of less that 100 worms are usually symptomless (the examples of helminthic therapies in the article used up from 1000-3000 worms), anything more than that number may cause additional GI symptoms such as abdominal pain, bloody diarrhea, and even bacterial infections from the worms penetrating the intestinal lining. These symptoms are for acute expose to the worms only, but seeing as the worm eggs in helminthic therapy need to be reintroduced continually in order to remain symptom free (from the autoimmune disease), it is possible that more serious chronic symptoms can occur. This is why I don’t think helminthic therapy will be a viable option in the future mainly because the costs outweigh the benefits.

However, in the article by Rook he states that the GI microbiota also exert a degree of immunoregulatory control. Because the bacteria in the gut flora is so numerous and has a great deal of diversity/ variation from person to person, it presents a better target in developing therapies against autoimmune diseases. Specifically in determining which species of bacteria are helpful in reducing the symptoms of certain diseases and which species exacerbate the symptoms.    

First Respondent

     First of all, wow. I would never ever willingly consume stomach parasites as a form of therapy or treatment. For me it is likened to that of leeching as a barbaric form of treatment. However, the results of Loke’s study are shocking and bizarre. He found that ulcerative colitis symptoms can be significantly reduced with helminths infection because the worms stimulate mucus production and prevent bad bacteria from spreading. Although the results of his experiment are compelling, the article from Scientific American makes a great point that the sample size is just one. I am not sure a big enough sample size can be achieved because not many people would be willing to submit their bodies to parasitic infection, and even so it would risk bias because it could not be a double blind study. I am surprised that enough people were willing to participate in the trials that the article describes! As for the Microbe magazine article and the chapters we read for this week, I am convinced. When we are exposed to more germs are immune system functions better, when we are not exposed to germs our immune system is not going to be able to handle germs when we eventually run into them. It makes sense. In a past anthropology class I learned that obsessive hygiene around new borns and younger children, parents who attack their children with wet wipes, those children have been shown to have lesser immune systems than their dirty counterparts. The microbe article described that in rural farming areas significantly less children have hay fever and allergy disorders, and I for one would like to take this moment to scold my parents for living in an urban area since my severe seasonal allergies are such a pain in my neck. The section on vaccinations in Chapter 8 made me cringe, I would be absolutely terrified to receive an active vaccination or to be around someone who has received it. As we discussed in class and as mentioned in the text, when the majority of school children are vaccinated some who go unvaccinated can coast by. When not enough are vaccinated diseases and infections can be life threatening to those unvaccinated. When parents today are unwilling to vaccinate due to falsified myths this can be a huge problem for their children and others. After reading these texts, especially after the information on helminth therapy, I have a psycho somatic stomach ache! 

These Old Friends of Ours (Respondent)

One of the first readers makes a good point about the increased prevalence of certain autoimmune disease and inflammatory disorders in urban centers: our current problems are the result result of a tradeoff. The elimination of harmful bacteria through antibiotics was a game-changer. While the grave problems the misuse of antibiotics has caused in treating what should be easily-curable infections should makes us critical, the fact is that implementing good hygiene practices along with the occasional use of antibiotics has drastically reduced mortality rates everywhere.

What I think scientists who are advocating for the “old friend hypothesis,” including Jabr and Rook, are stressing is that our germ-phobic culture has swung too far to one extreme: all germs are bad and must be killed. Our thinking is simply wrong. Instead of viewing bacteria and helminthes as creatures to be avoided at all costs, we must instead think of them as we would any other animal: some are dangerous and should be avoided and others we can live in harmony with and even use to our benefit. The same paradigm shift can be seen in scientists studying the microbiome. The unpleasantly named practice of “fecal transplants” has quickly been recognized as a viable means of treating Clostridium difficile infection (CDI), and its success rests on the notion that we need bacteria in order to be healthy.

Continued research into these “old friends” of ours and a shift in our thinking may be what is necessary to maintain a healthy society in the near future, and I think Rook and Jabr do an excellent job in outlining why this field is so promising and so critical to the future of medicine.  

First Response 4/12

This weeks topic of bacteria and parasite exposure in order to treat or prevent diseases both interested me as well as left me feeling doubtful. The data that was presented by Jabr article on stomach parasites as well as the Rook reading on bacteria exposure and it's effect on autoimmune function and development were both fairly strong points and made a lot of sense. I completely believe that a lack of exposure to traditionally prevalent bacterias and organisms in our environment is constricting our auto immune growth and our resistance to allergy and disease. However, Rook continually called on the boom in urbanization as well as the developed societies hygienic practices as being at fault for an increasing vulnerability to illness and allergy. He frames the cleanliness and the elimination of certain bacterias in a seemingly negative and harmful light to modern society, completely disregarding the amounts of serious illness that has receded in members of developed societies and cultures. The article completely failed to hit on the amount of trade off that is experienced between diseases that hit underdeveloped and less hygienic cultures with the disease vulnerability that is now being felt in more structured and hygienic societies. When actually looking into what we are gaining in terms of health and disease avoidance with a very clean urbanized society along with the increase in risk apparent with decreased exposure to traditional bacteria, the effects being felt by modern society must seem much less menacing than they are presented in Rook's article.

Similar sentiments remain with me after reading Jabr's article on the use of stomach parasites to treat the symptoms of bowel and colon diseases. The idea of infecting a patient with stomach worms to lessen painful symptoms of these illnesses is backed with strong biological and scientific support, with the increased production of mucus. Furthermore, the tested statistics of those with stomach illness infected with parasites against those not infected measuring experienced symptoms saw overwhelming support for the infection of worms to treat the negative effects of illnesses as being a successful treatment method. However, I remained skeptical of this theory due to the negative effects that are often associated with tapeworms and other parasites in the human body. In the Jabr article, many of the side effects that came with the infection of parasites in humans were comparable to the symptoms experienced by patients with serious stomach illnesses. I think that the idea of parasite treatment has great potential and is also very helpful in aiding our understanding of what fights the symptoms of those with stomach illness. However, I would need to see more data on parasites treating the symptoms successfully with only a negative downside experienced by patients before I would consider it a truly viable treatment option. I also believe that a less harmful cure must continually be strode for in the medical field.

The Grandmother hypothesis applies to whales too!

This article actually helped me to understand the grandmother hypothesis a little more. Whales are similar to humans in that females live long past menopause. I know we had discussed it in class, but it now makes sense to me that females would be the ones to aid fitness as a trade off from losing fertility. It is also very interesting to see such a similar social environment in whales as exists in great apes. This leads me to ask what other species see patterns of grandmothering and fitness. Surely they would be species that live beyond reproduction and are also very social. This is a very narrow category and I cannot think of another species that might see this phenomenon.
http://www.bbc.co.uk/news/10451533

Searcher: Aubrey de Grey - 8 years later

I had watched Aubrey de Grey’s TedTalk at least twice before we watched it in class on Monday.  I found it fascinating.  Could an unlimited extension of the human lifespan really be possible? And within my lifetime?  Although I certainly was not (and still am not) banking on this happening, the thought was, admittedly, slightly comforting.  People were actually doing research on how to overcome the apparent biological inevitability of growing old, something I and undoubtedly many others are not looking forward to.

Searching around for something worthwhile to write a blog post about, I stumbled upon a presentation at TedxDanubia that de Grey gave in 2013.

https://www.youtube.com/watch?v=qMAwnA5WvLc

While the 2005 TedTalk seemed to be mostly just theory, this talk delves further into the actual research de Grey is doing, much of which has been done in the years since 2005.  What he hopes to accomplish overall seems like the stuff of a utopian (or possibly dystopian..) fiction.  His goal is to provide a rejuvenation treatment that will reverse or cure the accumulation of damage that happens to our bodies before it leads to disease, essentially allowing us to remain at peak health indefinitely.  He described in an interview what this treatment might look like: go to the hospital to get your treatment, stay for a day/week/month, and come out good as new.  However idealistic or great such a treatment might sound, there are serious social implications that would need to be considered.  There would certainly be a social stratification in who could obtain these sorts of treatments.  And, like we said in class, a population overload is a real concern.  Humanity in its entirety is not going to make a collective decision to stop having children, and an extension of the reproductive years could possibly lead to an exponential increase in the number of children that are born.   

That being said, I don’t think de Grey’s research should be wholeheartedly dismissed as foolish or too idealistic to actually work.  Maybe small steps towards his ultimate goal could lead to insights, and possible treatments, for debilitating diseases of the elderly.

Searcher How Grandmothers Gave Us Longer Lives

This week in class we have been exploring the question of why we age, and one of the proximate reasons that we looked at was the grandmother hypothesis. This states that the behaviors that grandmothers exhibit, such as providing the mother support with childcare and provision increases longevity. The grandmother hypothesis is interesting because humans are the only primates that live long after menopause and humans are also the only primates in which the grandmother provides support in taking care of the child. Rebecca Jacobson goes into some of the reasons as to why having grandmothers around has helped our longevity. One of the reasons as to why humans live past the years of menopause is that the more grandchildren a grandmother has the more genes that she will pass on. Grand mothering might have also been one of the factors that caused us humans to be so social.  Peter Kim made a mathematical model to see you long it would take our lifespan to change from that of our ape ancestors to that of modern hunter gather groups by adding grandmothers that were one percent of the female adult population and could take care of any child over the age of two. What he found was that the number of grandmothers in that population rose to more than forty percent in less than 60,000 years and the human life expectancy doubled (Jacobson, 2012). Grandmothers are very important to society but I think there are also other factors that increased human longevity. 

http://www.pbs.org/newshour/rundown/how-grandmothers-gave-us-longer-lives/ 

The Quest to Live Forever: A Searcher's Findings!

Everyone seems to be eagerly discussing the topic of "immortality," so I might as well join the bandwagon (and because it's actually something that interests me). Immortality is a concept that's been ever-present in all of our lives, in some shape or form. The link below takes you to a book called "Immortality: The Quest to Live Forever and How it Drives Civilization" by Stephen Cave. 

http://www.amazon.com/Immortality-Quest-Forever-Drives-Civilization/dp/0307884910

The book reveals to us how immortality has driven us in the past, present, and will continue to drive us well into the future. It's been done through the use of religion, to instill faith and hope that our human bodies are nothing but shells protecting immortal souls. And the strange thing is that actual believers have, in a sense, achieved immortality. By convincing themselves of eternal life, they will die with the hope that they will reach the other world. And no one has come back to tell the tale in our day and age so one can't completely rule it out. It's a weird way of thinking about immortality, especially if you're unconvinced of a "heaven" or "reincarnation", but hey it works for some people! And to me, it's crazy to think about how long ago these thoughts transpired and that such thoughts give people the will to live and do good. 

There's also the bountiful number of antibiotics and vaccinations that have been created simply to prolong our earthly existences. In addition, there exists the concept of a "legacy," or gaining immortality through our descendants. And all of these things have driven humans towards finding out more and more about this world we inhabit, throughout the ages.

Despite all this, the author believes that "everything the soul was supposed to explain - thoughts, consciousness, life itself -- has been shown to be dependent on the body. We therefore have every reason to believe that all these facilities --from memory to emotion to the most basic form of awareness --cease when the body ceases. There is simply nothing left over for the soul." 

Any thoughts on this? I personally think that not existing one day is absolutely frightening. However, the fact that I have no recollection of the past before my human birth means that I did not exist. But now that I do, I cannot fathom no longer existing again (I think too much about this - It's a problem). So, living forever sounds pretty sweet to me (except for overpopulation ...and a number of other things). 

Why Do We Age? A comparison. (Searcher)

In this week's class (and readings), the question "Why do we age?" has been greatly explored. Throughout yesterday's class, we explored many different reasons, like socioeconomic status, and just inevitability. A lot of aging has to do with the breakdown of DNA and how that affects the rest of the body. An idea that as we stop reproducing (due to age), our likelihood of dying increases, because natural selection does not really care about life after successful reproduction. So why do we age?

During some online research about this topic, I was able to find a nice article on National Geographic's website, which compares the aging and fertility between different species of organisms. I thought it was very interesting and informative. Something very interesting is that not all species experience a drop in fertility and a rise in mortality with age.

The desert tortoise, actually, experiences the opposite. As it ages, its fertility increases and its mortality decreases. This is not something we see in humans, or often in other animal species, which is particularly interesting. In a similarly interesting note, the Hydra (hydra magnipapillata), a water polyp, has nearly identical birth and death rates, all throughout its lifespan. This article also compares a few other species, but you'll just have to read it to find out!

The Case of the Immortal Jellyfish (searcher)

The lesson of this week is that we all age. Eventually, though various biological reasons ranging from a breakdown of DNA repair mechanisms to trade-offs that benefit us early in life, our bodies are programmed early on for eventual senescence. However, it would appear that there is at least one species of jellyfish that can live forever.

Turritopsis nutricula isn’t much to behold. It’s only about 4-5mm in length and looks like your typical jellyfish. However, what distinguishes it from other life forms is that it has the ability to undergo complete cellular transformation. If it is on the verge of death (via injury or starvation, for example), it can begin a process called transdifferentiation in which its body breaks down its cells and transforms them into different cell types. If you were to apply this to humans, it would be like the cells in your liver having the capability to transform into nerve cells. After the process is complete, it’s as though jellyfish is as good as new—a younger to boot. It reverts back to its polyp stage and will grow and reproduce from there.

Turritopsis dohrnii, a relative of the immortal jellyfish, also shares aits unique ability to "age backward."

There are limits to immortality, though. Transdifferentiation can only occur after sexual maturation. And presumably, if an adult Turritopsis were to be gobbled up by a predator it would pretty definitively cease to exist. However, this little creature is providing scientists with new opportunities to not only understand the process of aging but also may provide solutions for the kinds of therapies we previously looked to stem cells for.

Why do we Age?

Growing old really frightens me. I am not the type of person who likes to talk about ageing, because all I associate ageing with is death. Seeing my parents’ age is what scares me the most. I found this week’s article to be very interesting. This article discusses ageing in an evolutionary way, as in reproduction. In this article ageing is not looked upon as a negative thing but as an evolutionary process, and has gotten me to somewhat look at it as this process. Our main purpose on this Earth is to reproduce, and after that stage we start to age and deteriorate. Ageing starts when we have completed our goal of evolution which is producing an offspring that is fit for the environment.

I have also come to understand that menopause in women is not the end of the world as most people make it seem. It is just another stage in the evolutionary process. A stage where women reach after they have completed their goal.

First Reader 4/6

I thought that the article on why we age was very interesting. Kirkwood and Austad talk about three theories that provide explanations of why aging occurs. The theory that I found most interesting was how senescence is programmed to limit population size and allow the adaptation of organisms in changing environments. This seems to be true mainly for humans. One large flaw is the fact that wild animals don’t live long enough to grow old. It is hard to say that someone died of old age. Once you get older you are more susceptible to disease. Another theory was that of ‘pleiotropy’. This stated that pleiotropic genes that had good early affects would be favored even if they had poor affects later on. This is an important life-history trade-off, which is something we talk a lot about in this class. This is also a big part of the third theory, the ‘disposable soma’ theory. These two theories are very similar. The pleiotropy theory is based on a general pattern of gene action, while the other focuses specifically on mechanisms. Why we age is interesting but so is how we age. Our life expectancy has gone from around 47 in 1900 to around 80 in 2013. That is a drastic difference. Reading this article has made me want to do more research on why and how we age.