Daily Archives: April 17, 2014

Summary of Reading for 4/17/14



Genetic Signature of Bacterial Pathogen Adaptation During Chronic Pulmonary Infection

            The main point of this article was to review and summarize the research project done by another group of scientists. These scientists were trying to find out about how the bacteria in patients with respiratory infections evolve within the person’s body over time. For instance, do the bacteria just simply clone themselves? Are they under selection pressures created by the environment of the human lungs? What is most exciting about this paper is that learning about how the bacteria that infect these kind of patients evolve could help develop new and better treatments to treat respiratory infections. Perhaps a regiment more like HIV is appropriate for example since the bacteria that infect these patients evolve and diversify as well.

The scientists looked at the bacteria in sputum samples taken from five patients with cystic fibrosis. They “sequenced pooled population DNA at a very high depth of coverage.” This allowed for an increase in detection of allele frequencies with less cost. One of the patients had whole bacterial genome sequencing, and the other four had only certain colonies sequenced.  It was found that “the majority of mutations were polymorphic.” Other indicators made it clear that the bacteria were under selective pressure that diversified them and created a state of heterogeneity.

The implications of this study are vast because they could greatly impact how we treat respiratory infections. It will probably change the drug regiments of these patients and maybe even completely new drugs will be made and distributed.



The fear of vaginal birth

Although it was awhile ago, the discussion we had about birth in class stuck with me. As members of our cultural society, it’s difficult to differentiate between what’s actually true and what we think is true because of culture. In class, someone mentioned breech babies and how that position necessitated a cesarean section – but it doesn’t. Health and medicine in general have become very medicalized. Normal development processes like  menopause are now considered “conditions.”

This article provides a concise overview of why cesarean section births are on the rise. In class, Nelle had provided an example of how cesarean sections weren’t always the best option. The pressure involved in passing through the birth canal actually helps remove amniotic fluid from the baby’s lungs. Therefore, when a baby is delivered surgically, he or she may go on to develop issues like asthma and other respiratory challenges – all because of the manner in which he or she was born.

When researching the other benefits to a vaginal delivery, I came across one noteworthy example. Throughout the semester, we have talked about gut microflora and its influence on an individual’s health. Well, there’s evidence that supports the idea of a cesarean section  birth may stunting development of gut microflora. From other readings, we know that gut microflora influences digestion, metabolism, cardiovascular health and more. Additionally, babies born vaginally had gut microflora similar to that of their mother’s, while babies born by cesarean section had gut microflora similar to the bacterial colonies found on skin surfaces. I’m sure there are numerous other effects of delivery mode on both the mother and baby’s health outcomes. I think it’s important to be informed with evidence-based research, primarily because as we saw in class, we are all dramatically influenced by culture.

Here are links to the two articles I found:
1. http://journals.lww.com/jpgn/Abstract/1999/01000/Fecal_Microflora_in_Healthy_Infants_Born_by.7.aspx
2. http://www.pnas.org/content/107/26/11971.short