Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Illnesses and Injuries

Leave a comment

Hydrogen sulfide – the gas we hate to smell, but can’t live without

Although hydrogen sulfide (H2S) is most often associated with manure and the smells of rotten eggs, research has shown it plays important physiological roles. In fact, our bodies actually produce H2S within our cells. Other source of H2S include sulfate-producing bacteria in our gut and dietary intake (such as garlic and cruciferous vegetables). H2S is a member of a group of gasotransmitters, referred to as the ‘reactive species interactome’, that […]

Continue Reading →

Leave a comment

How snakes fight infection quickly

In honor of St. Patrick’s Day today, I thought we’d talk about snakes today. Vertebrates defend themselves from infections with the help of the adaptive and innate immune systems. The first responder to an infection is typically the innate immune system, which is not specific to a particular pathogen. This system helps to prevent the infection from spreading and uses various toxins to kill pathogens. The adaptive immune response, on […]

Continue Reading →

Leave a comment

The biological importance of carbonic anhydrase enzyme

Carbonic anhydrase is an important enzyme that regulates the acid-base balance of an organism. In fact, carbonic anhydrase (CA) is so important to homeostasis, it is found in all living organisms studied to date – from microorganisms (like bacteria) to mammals. As the name implies, this enzyme is responsible for catalyzing the hydration of carbon dioxide, which is a reversible process (see figure above). In other words, it speeds up […]

Continue Reading →

Leave a comment

New cancer diagnostic tool

Scientists have come up with a truly unique tool to try to detect cancer – ants. Yes, ants. Ants are known for their strong sense of smell, which helps them locate food pretty well. Interestingly, some forms of cancer can alter the smell of urine and ants may be able to detect those changes. Their findings on the potential use of ants as “bio-detectors” of cancer were published in the […]

Continue Reading →

Leave a comment

The complex interplay between pathogens and our immune system

I read an interesting review article explaining how cells evolved the ability to kill off pathogens and, in turn, how pathogens evade death. It is kind of like a perpetual game of ‘cat and mouse’ in which the interaction between animals and pathogens drives the evolution of host defenses against infections while at the same time driving the evolution of pathogen strategies to avoid detection. According to the review article, […]

Continue Reading →

Leave a comment

Arizona physiologists gathered recently for their annual meeting

The Arizona Physiological Society, a chapter of the American Physiological Society, hosted their 15th annual scientific meeting this past weekend! Here are some highlights… The Keynote Address was presented by Dr. Harold D Schultz, Professor in the Department of Cellular and Integrative Physiology at the University of Nebraska. His talk focused on the physiology of heart failure and how the nervous system regulates blood pressure. This year’s Arizona Distinguished Physiologist […]

Continue Reading →

Leave a comment

Mice have special ‘jumping genes’ that help them survive viral infections

Researchers at the University of New South Wales (UNSW), Sydney discovered a ‘jumping gene’ that prevents the immune system of mice from overreacting to a viral infection. Jumping genes are movable nucleic acids, or transposable elements, that make up nearly 2/3 of the genome in mammals. They help regulate the expression of genes. Some transposable elements in the genome are new and some originated in ancient times. In the new […]

Continue Reading →

Leave a comment

Aging and Immortality

Have you ever heard of the ‘immortal’ jellyfish, Turritopsis dohrnii? These tiny creatures (about 4.5 mm) are aptly named for their ability to essentially live forever. According to the Natural History Museum, when these jellyfish are damaged, they can actually revert to a prior life cycle as a polyp and become an adult jellyfish (aka, medusa) all over again. This process is called transdifferentiation. Check out this video from the […]

Continue Reading →

Leave a comment

New study discovers how zebrafish mend a broken heart

A new study has helped unravel the mystery explaining how zebrafish regenerate a broken heart. Their findings, published in Nature Genetics, reveal how these amazing little fish can regrow up to 20% of their heart in only 2 months following an injury. This regeneration is driven by signals released from special cells called fibroblasts. When the heart of zebrafish is injured by a stimulus that mimics a heart attack (using […]

Continue Reading →

Leave a comment

Under pressure: One way our bodies regulate blood pressure

Did you know that blood vessels come fully equipped with the ability to help regulate blood pressure? This is possible because of smooth muscle cells that wrap around blood vessels (see image above). Because they wrap around the inner layers of the blood vessel, when these cells contract, the lumen od the blood vessel becomes narrow and increases blood pressure. When they relax, the blood vessels widen thereby lowering blood […]

Continue Reading →