Month: March 2020

One project that I would be most excited about funding would be how microbes during pregnancy and birth could affect one’s life down the road. There seem to be a few different consequences resulting from a newborn’s microbiome that can affect their life down the road. For example, being born via C-section seems to be correlated with asthma and allergies that are usually life-long diseases. Additionally, being babies born via C-section seems to contain a higher proportion of bacterial antibiotic-resistance genes compared to vaginally delivered infants. This could lead to more infections as an infant, risking the child’s life. Also, being breastfed vs formula fed has an impact on the microbes colonization of the mouth, with breast-fed infants containing oral lactobacilli with antimicrobial properties. Additionally, when mothers have oral infections it seems to have negative effects on their child such as pre-term births. The extent of how microbes colonizing newborns is varied and can have many long term effects that I would be interested in learning about. I think we would learn how specific behaviors that affect microbiomes, ultimately influence the lives of newborns. For example, if infants are colonized with skin bacteria in C-sections and not vaginal bacteria, then shortly after birth doctors should consider somehow inoculating the child with their mother’s vaginal fluids so they get the benefits and prevent asthma/allergies. Or, if it was proven that mouth infections of the mother can cause pre-term births then the doctors could work towards ridding the mother of the infection before it negatively affects their child.

-obesity

-stomach cancer

-cervical cancer

-irritable bowel syndrome

-inflammatory bowel disease

-asthma

-depression

-autism

-allergies

Most of the diseases that I listed in week one did not pertain as much to the gut as the ones I have listed here. But, there are a few similarities in the non-infectious diseases I listed in both posts. Some fo the similar diseases are asthma, cancer, and depression. The ones I failed to mention were one such as irritable bowel syndrome, inflammatory bowel disease, obesity, and allergies.

I think the most important topics I will take away from this course will be obesity and asthma, with obesity being the one that sticks with me the most. Obesity will probably stick with me the most because I wrote my final essay on it but it also has some of the most interesting mechanisms. The way that microbes can influence gut hormones is astonishing. Additionally, asthma is a disease that has been correlated with C-section births. I was born via C-section and also live with asthma so I wonder if this relationship was the cause of my asthma and look forward to future research on this topic.

Microbes have been shown to have a relationship with stress and anxiety-related behaviors. Studies have shown exaggerated neuroendocrine responses to stress and anxiety-like behavior in germ-free mice. This observation was reversible when mice were colonized with bacteria, reducing anxiety-like behaviors. But, this phenomenon is thought to only be possible if mice are colonized in a critical time window during the early-life/adolescence. Additionally, there has been evidence of the microbiome modulating emotional behavior. Probiotics with Bifidobacterium and Lactobacillus have shown to have beneficial effects on anxiety and depression in a few different studies. Another mental state that microbes seem to influence is that of autism spectrum disorder. ASD-like behavior of mice was associated with alterations in the gut microbiome. A study also showed that germ-free mice showed reduced sociability and had social cognition deficits compared to conventionalized mice. These social deficits were reversed by the colonization of bacteria. Lastly, gut microbes have been shown to exert influence over leptin and ghrelin, appetite-regulating hormones. There have been shifts in science that indicate microbes do indeed affect the brain and a persons’ mental state but much of the research done has been on rodents. More research is required to truly prove this causational relationship in humans and understand the mechanisms at which microbes affect the brain.

Can experiments detect differences that matter?

• This question is very significant because experiments seem to find differences in bacteria diversity amongst obese and healthy individuals. But the question is how significant are those differences? There is great diversity amongst healthy individuals bacteria itself, and there isn’t an established “healthy” microbiome that all others can be compared to. Microbiomes vary from person to person. So, do the differences between obese and healthy person microbiomes even matter if there are already established differences from person to person? Being able to label a specific difference in the microbiome as causational for a disease isn’t possible if there isn’t even an established and well-characterized network to compare it to.

Does the study show causation or correlation?

• When interpreting scientific literature this is a very important question to consider. While the results may show a correlation between a certain microbe and outcome, it can not be labeled causal until the reverse causational relationship is explored. If a journal states a microbe causes an outcome/disease, they must be sure to rule out the disease or outcome isn’t causing the presence of the bacteria. Additionally, Microbes could be mere bystanders during certain outcomes and just measuring whether they are present or not does not allow for the relationship to be named causational. The literature must have real proof of causational relationships by providing mechanisms of action. This leads to the next question to consider.

What is the mechanism?

• This question is very significant in evaluating scientific literature. Without evidence of the mechanism, the relationship can merely only be correlational. Observing the correlation between microbes and certain outcomes is a step in proving a causal relationship. But, the mechanism behind how microbes can cause certain outcomes is ultimately the best evidence of labeling the relationship as causational. By conducting experiments that rule out certain taxas and confounding factors, allows researchers to pinpoint whether a certain microbe affects human health and then study how it does so.

How much do experiments reflect reality?

• The significance of this question lies within the methods and conduction of the experiment. It seems that in many experimental studies the setting is so fabricated and unrealistic that their findings may be worthless. If researchers are implanting germ-free mice with microbes and observing what happens to them, they are completely ignoring other factors and creating a very unrealistic setting. No person is going to be “germ-free” such as these mice, so the results of the experiment might not even be applicable if they can’t repeat such results in a human.

Could anything else explain the results?

• When studying the microbiome, it would be foolish to think that bacteria cause outcomes without any other contributing factors. Diet is a very important factor that researchers seem to neglect when conducting an experiment. They transplant microbes into mice, observe reduced fat, and publish all these articles that people can lose weight with a fecal transplant. The media then takes these reports and blows them up even further, all without taking into consideration one’s diet and how that could influence the gut microbiota rather than a transplant.

I think the most helpful question when discussing controversy is the mechanism of action. Like I said before, you can observe relationships between microbes and outcomes but that observation only provides evidence for correlation. Knowing the mechanism and explaining it provides a piece of whole new evidence for a side of the controversy. If one side can only support their claim with correlations while the other actually has a real mechanism of action, then the side with a mechanism explanation is much easier to believe. The mechanism can actually explain and support their thesis, which is why I think it the most important thing to consider when discussing a controversy.

It felt a bit odd doing the review of someone else’s paper in such a formal way by filling out a review form. It kind of made me rethink some of the areas in my paper that could use improvement. I have never done such a detailed review before, looking for very specific things in people’s papers. Most reviews I have done before involve mostly just reading through someone else’s paper and checking boxes such as grammar, structure, answering of the prompt. But this review had us looking in-depth at how the author of each paper found evidence surrounding controversy using primary research and the way they were able to convey it to their audience. Additionally, it incorporated a review of how they used their evidence to support a thesis and a recommendation for health in regard to their specific topic. Some things I learned to apply to my essay is to look over the way I explain research to the audience to make sure it is appropriate and understandable. Additionally, look over and make sure I tie that evidence back to my thesis and recommendation in a way that supports the bigger picture and context of my topic.

Peer review is a process of verification of studies before they are published for the general public. Typically, a group of researchers conduct a study and write their results in the form of an article. That article is submitted to a journal for publication. The editors of the journal send the article to other scientists in the same field. If those scientists feel that the article is of high enough quality and meets good scientific standards they will approve the publication of it. The pros of this method of peer review are allowing other scientists to review the work done by researchers before their work is made public. That way some random joes don’t run an experiment from their home and publish the results of a poorly ran study as conclusive evidence for various topics. It is a verification process in that sense. The cons are that the approval is subjective as it isn’t the same group of people in each field who follow a specific set of standards. The results of a study could seem plausible to some scientists who support that sort of research while others might refute it and find flaws in the methods. Overall, the subjectivity of the scientists doing the review could impact the credibility of the results.