Writing Exercise #9

  • Excessive use of hand sanitizers: while hand sanitizer and other soaps can be necessary, their excessive use can lead to decreased exposure to microbes because they tend to kill a wide range of bacteria.
  • Excessive use of antibacterial cleaning supplies: in peoples’ homes, the use of cleaning supplies can kill many bacteria, creating nearly sterile environments. This causes a decreased exposure to microorganisms.
  • Less time spent playing outside: people, especially children are exposed to a plethora of microbes when playing outside, and over the course of the past few decades with the introduction of video games and the internet, children have spent less time playing outside.
  • Increased antibiotic use: antibiotics often kill a wide range of microbes, many of which are beneficial symbionts of humans. By taking antibiotics unnecessarily or for prolonged periods of time, a person is selecting for microbes with the capacities to evade these antibiotics.

Writing Exercise #8

I thought it was really interesting to learn about how delivery method influences the development of a baby’s gut microbiome. I never really thought about it until a few weeks ago, but now I am wondering whether or not the higher rates of C-sections are a contributing factor to increased rates of metabolic diseases and obesity in American kids. Today doctors perform a lot more unnecessary C-sections. Sometimes it’s merely out of convenience, without thought about how it actually can influence a child’s health. I read in an article recently that kids born via C-section have a way higher chance of developing childhood obesity. I wonder if there will ever be a way to help inoculate children who were born via C-section by necessity in order to help them be healthier in the future.

I highlighted the word unnecessary because I think as humans we do a lot of things in the name of “being healthy” that we really don’t need to be doing. Our bodies are amazingly capable of maintaining our health and homeostatic balances. For millions of years we survived without the need of many treatments we use daily. I’m not at all saying that we should cut out many of the medical treatments and remedies that have saved and improved so many lives, but I think that we do live in a time where so many things are overly medicalized. It seems that so many things that used to be treated with at-home remedies now require doctors visits and prescription drugs.

I think that one of the most unnecessary treatments that we see today is the overprescription of antibiotics. Often, physicians will prescribe antibiotics for illnesses that aren’t even caused by bacteria. I think that this could be a really interesting topic for my final paper, and I will look further into it in the coming days. Things I could talk about in the paper could be why doctors are so quick to prescribe antibiotics, what causes bacteria to become resistant, what next steps could be, and what the future looks like for the field of medicine with respect to antibiotic treatment (will it be phased out, will we develop new ones, will there be new/better ways to treat infections in general?)

Writing Exercise #7

  • Method of delivery: when infants are born vaginally, they harbor vaginal microbes that begin to colonize their gut microbiome. However, in infants born via C-section, there is a disruption of transmission of these microbes. Instead, they often are first exposed to skin, not vaginal, microbes. Furthermore, the maternal vaginal microbiome changes during pregnancy, apparently in order to provide the fetus with a specific microbial inoculum at birth.
  • Maternal weight: mothers who are obese often have disrupted vaginal microbiomes, which can contribute to the differential infant microbiome development compared with mothers who are not obese.
  • Breast feeding and bottle feeding of newborns: breast milk contains certain probiotics that colonize the infant’s gut prebiotics that help nourish these microbes. This combination is usually not present in formula, and aids in the development of a more uniform gut microbiome than that found in formula-fed infants.
  • Perinatal antibiotic treatment: if a mother undergoes antibiotic treatment soon before giving birth, the vaginal microbial community could be greatly disrupted. Also, antibiotic treatments could cause a change in uniformity of the breast milk, which could have a differential effect on the development of the infant’s gut microbiome.

Reference:

Mueller NT, Bakacs E, Combellick J, Grigoryan Z, Dominguez-Bello MG. 2014. The infant microbiome development: mom matters. Trends Mol Med. 21(2): 109–117.

Writing Exercise #6

Personally, I take antibiotics whenever they are prescribed to me by a physician, and I am pretty diligent in making sure that I take the entire course. Before a tonsillectomy, I often got strep throat multiple times a year, and each time I was prescribed a course of antibiotics. Generally, I tend to trust my physicians, as they have gone through extensive training and education, and I try to follow their advice as closely as I can. However, among many physicians there is a growing concern about the over-prescription of antibiotics. Just today I shadowed a physician who was wary about the negative consequences associated with the over-prescription of antibiotics, and even she said that there are some infections for which an antibiotic regimen is unavoidable (i.e. urinary tract infections). When contemplating whether or not to take antibiotics, it is important to weigh both the pros and cons of the treatment, and also to consider the negative consequences of neglecting to follow a physician’s recommended course of treatment.

Writing Exercise #5

I like to consider myself a fairly healthy eater. While I do not often adhere to strict diets, I like to make sure that I balance my consumption of different types of foods, including fruits, vegetables, grains, and protein. Also, I tend to get macronutrients from multiple different sources (i.e. protein from lean meats and beans). A diverse diet provides a wide array of nutrients for the gut microbiota to feed on, which thereby contributes to the development of a more diverse gut microbiome. I also make sure that I eat some form of probiotic when on a course of antibiotics. While both of these contribute to an increase in diversity of my gut microbial community, some things can limit it. Aside from occasionally taking antibiotics when I am sick, eating foods, especially meats, that have been treated with antibiotics can decrease the overall diversity of my gut microbiome. This is often an unconscious choice that is made when buying groceries, because sometimes I opt for cheaper options that are treated with more antibiotics, as opposed to a more organic and expensive product.

Writing Exercise #4

  • Antibiotics could cause a change in the gut microbial community by killing certain microbes. This would cause a change in the composition of the community. In some situations, this could be beneficial (as in the case of an infection), but often, beneficial microbes are killed in the process, leading to a detrimental effect on human health.
  • Changing one’s diet could also greatly alter a person’s microbiome composition. For example, someone who has been a strict vegan for a long period of time may have an altered microbiome that is not accustomed to eating animal products. Digesting meat could be very difficult for them until the gut microbial composition is able to adjust to the change in diet. Changing diet could either have a beneficial or detrimental effect, depending both on the type of change in diet and the particular person’s microbiota.
  • Taking a probiotic could change the gut microbial community by introducing different microbes to the host’s digestive system, which often has a beneficial effect, especially after a round of antibiotics.
  • Taking a prebiotic would help feed beneficial bacteria that already inhabit a person’s gut, which would have either a beneficial or neutral effect on one’s gut microbial community. Prebiotics may help increase the number of “good bacteria” within a person’s gut by offering them additional nutrients.

Writing Exercise #3

In my opinion, HPV strains 16, 18, 31, and 35 should be included in the treatment plan. Together, these four strains account for nearly 80% of cervical cancers. Although treating these four strains would obviously be fairly expensive, it would be much less expensive than treating a patient who had developed cervical cancer, aside from being much better for the health of the patients.

Writing Exercise #2

1) In “Symbiotic gut microbes modulate human metabolic phenotypes” (2007), Li et al showed that the human gut microbiome has a strong influence on metabolic phenotypic variation within populations. 2) Li et al demonstrates that variation among individuals’ gut microbiomes can help explain differential metabolism and therefore health. 3) The purpose of this paper was to lay a foundation for functional metagenomics, in order to advance knowledge of the wide array of functions that the gut microbiome has within the human body. 4) This study has the potential to lead to increased knowledge about the effects the microbiome has on health, metabolism, and obesity.

Writing Exercise #1

Many human non-infectious diseases can be caused or influenced by microorganisms, including:

  • Chronic liver disease,
  • Cervical cancer,
  • Chronic gastritis and peptic ulcers,
  • Lymphoma,
  • Asthma,
  • and Diabetes.