Sunday, May 5, 2013

First Reader: Cancer

This post is a first reader to the article "Evolutionary foundations for cancer biology”. I found this article to be especially interesting, I feel that more and more people are beginning to understand the interconnectedness of their day-to-day decisions. Throughout my life I have been give the impression that individuals tend to consider “things” (as in any one thing e.g. food, television, cleaning supplies, clothing) to be separate from one-another. People seem to like to believe that life is simpler than science is revealing it is, most likely because this would then add a level of responsibility that many would not be willing to address. If people actively acknowledged the cleaning supplies they used were carcinogenic then they would have to put in extra effort to find a none harmful solution when it is much easier to deny their lethality in the first place. As we as a species have began to probe the reality that every action and decision we take and make there are both direct and indirect consequences that may effect us down the road, sometimes not for half a lifetime. As talked about in the reading, precancerous growths can be in existence many years before the cancer itself manifests and these growths could have been triggered by a simple infection or short exposure to a substance. If there is one thing this reading has taught me it is to avoid everything.

Aktipis, C. Athena, and Randolph M. Nesse. "Evolutionary Foundations for Cancer Biology." The Authors 6 (2013): 144-59. Print.

Responder: "Viruses and Us"

This post is in response to Nicholas's first readers post "Viruses and Us". Nicholas mentioned the relationship of gut flora and human health in his post and I thought I would explore it a little further. Virtually all multicellular organisms live in close association with surrounding microbes, and humans are no exception. The human body is inhabited by a vast number of bacteria, archaea, viruses, and unicellular eukaryotes. The collection of microorganisms that live in peaceful coexistence with their hosts has been referred to as the microbiota, microflora, or normal flora (Kunz et al, 2009). The composition and roles of the bacteria that are part of this community have been intensely studied in the past few years. However, the roles of viruses, archaea, and unicellular eukaryotes that inhabit the mammalian body are less well known. It is estimated that the human microbiota contains as many as 1014 bacterial cells, a number that is 10 times greater than the number of human cells present in our bodies (Kunz et al, 2009). The microbiota colonizes virtually every surface of the human body that is exposed to the external environment. Microbes flourish on our skin and in the genitourinary, gastrointestinal, and respiratory tracts (Neish, 2009). By far the most heavily colonized organ is the gastrointestinal tract (GIT); the colon alone is estimated to contain over 70% of all the microbes in the human body (Neish, 2009). The human gut has an estimated surface area of a tennis court (200 m2) and, as such a large organ, represents a major surface for microbial colonization. Additionally, the GIT is rich in molecules that can be used as nutrients by microbes, making it a preferred site for colonization (Neish, 2009).

·      Kunz C, Kuntz S, Rudloff, S.Intestinal flora”. Adv Exp Med Biol 639:67–79, 2009.

·      Neish, ASMicrobes in gastrointestinal health and disease”. Gastroenterology 136: 65–80, 2009.

Searcher: Aging

I found THIS article, which is relevant to this weeks discussion on aging. It explains the following information, however, in less detail than I liked. So, I found s journal article that went into more detail. Owing to increased lifespan and subdued fertility, the world population aged 60 and over is anticipated to increase to 21.8% of the total population by 2050 (Lutz et al, 2008). Many individuals in an aging population will be inflicted with aging-associated diseases, such as various neurodegenerative disorders (Lutz et al, 2008). This phenomenon is of public concern and has thus spurred research in this area. It is believed that healthy aging could be accomplished if mechanisms underlying human aging were to be elucidated. Modern biological theories of human aging are classified into programmed theories and error theories. The programmed theories demonstrate that aging is regulated by some intrinsic mechanisms; by altered switch genes, changed hormones or even a dysfunctional immune system. On the contrary, the error theories emphasize cumulative environment-caused damage, such as reactive oxygen species, cross-linked macromolecules, DNA damage, and broken energy machines (Lutz et al, 2008). However, neither of these theories alone can explain all the phenomena and mechanisms at the root of aging. To date, the fundamental mechanisms of human physiological aging remain largely unknown

·       W. Lutz, W. Sanderson, S. Scherbov. “The coming acceleration of global population ageing” Nature, 451 (2008), pp. 716–719