Tutor profile: Omair A.
Subject: Health and Medicine
Why is antibiotic resistance growing as a societal challenge?
We are currently living in a world where the drugs we once used to treat simple bacterial infections are now becoming useless when we need them. The concept of antibiotic resistance is quite simple to understand. A "bug." or bacteria, develops a mechanism by which it can prevent the bacteriostatic (prevent growth) or bactericidal (cause death) effects of the antibiotic agents we have discovered or devised in order to treat infections. These mechanisms can vary from organism to organism, but often incorporate some form of somatic gene mutation or horizontal gene transfer, or the sharing of genetic material between one bacteria and another. This form of resistance is made possible by mobile genes, found either as plasmids or transposons (among other examples of mobile genetic material) that bacteria can acquire when given enough time. These mechanisms of resisting antibiotics have allowed for the development of superbugs, or multi-drug resistant organisms, that are especially hard to treat. These organisms can affect the immunocompromised, especially our elderly population that often face higher rates of hospitalization and health institutionalization that leaves them even more prone to nosocomial (or hospital-acquired) infections. As we try to manage patients with antibiotics, we are also given bacteria an opportunity to fight our weaponry by allowing them to evolve into forms that we may not be able to treat effectively.
Why do we need oxygen to survive?
Oxygen is an essential molecule to our growth and survival as humans. Oxygen is known to be the "final electron acceptor" in the electron transport chain that is found inside mitochondria. Oxygen is the final electron acceptor because it has the highest reduction potential, meaning it has the greatest propensity of being reduced. In this case, oxygen receives electrons that come from Complex IV of the electron transport chain to eventually form water. But what oxygen does is that it allows the electron transport chain to continue its course and allow for H+ ions to be pumped into the intermembrane space, where they accumulate and eventually form the chemiosmotic gradient that then flows down the FO/F1 ATP synthase that makes ATP- a ubiquitous energy-source in many intracellular processes. Without oxygen accepting those electrons, the chemiosmotic gradient would be weakened and less ATP will be made, therefore, creating disturbances in our homeostatic processes that will lead to cell injury and eventually cell death.
Why don't we become sick even though there are billions of bacterial cells inside of us?
Our bodies often have a mutual, symbiotic relationship with bacteria. We provide the nutrients they need to grow, and they provide us with nutrients that we need to sustain our normal functioning. One example is our gut flora, where bacteria can encounter nutrients that they can metabolize in order to proliferate and survive, and in turn bacteria produce nutrients that we can absorb (i.e., Vitamin K) that help us sustain homeostasis. There are also many "bad" bacteria that reside within ourselves - in our nasopharynx, our gut, and other places. However, they can't always make us sick-- that is, trigger an inflammatory state in our body-- because they require a particular trigger in order to infect us. This trigger might be a significant drop in CD4 T cell count, as is seen in HIV/AIDS, or some other disruption of homeostasis that allows these "opportunistic" organisms to produce their virulence factors and cause an infection. This occurs very often in our daily lives, such as when we sustain some trauma to our skin, which allows bacteria that may reside on our skin to travel and form an abscess or other hallmark of an infection.
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