hypoxia
dr. dolittle | July 29, 2017 Image via NOAA/Flickr
Pacific hagfish (Eptatretus stoutii), aka "slime eels", are primitive fish that occupy burrows on the ocean floor. Like earthworms, they have 5 hearts. They have no true eyes, no jaws, nor do they have a stomach. They locate their meals through great senses of smell and touch. In addition to small invertebrates, they are known for consuming carrion that fall to the ocean floor. By consume, I mean burrow into the decomposing carcasses and eating them from the inside out. Ew. Given their dietary habits, it is no surprise they are regularly exposed to little to no…
dr. dolittle | April 27, 2017
Here are the highlights from the final day of the meeting:
Carbon monoxide (CO) is not all that bad: Michael Tift, graduate student at Scripps Institute of Oceanography, described how the body naturally produces CO when red blood cells are broken down and CO can actually be protective against inflammation at low doses. His research was focused on measuring whether species that have more hemoglobin (from living in hypoxic environments) also have more CO. As it turns out, people native to high-altitude Peru do have higher CO levels than those living at lower elevations. Likewise, elephant…
oracknows | November 9, 2016Yesterday, I wrote about alternative medicine clinics in Germany that offer a combination of alternative cancer cures plus experimental therapeutics administered improperly outside the auspices of a clinical trial. In particular, I discussed two cases. The first was British actress Leah Bracknell, who is raising money to go to one of these alternative cancer clinics to treat her stage IV lung cancer. the second was a British woman named Pauline Gahan, who was diagnosed with metastatic stomach cancer and has thus far spent £300,000 for a combination of vitamin infusions, “detox,” and Keytruda…
dr. dolittle | October 18, 2016...in alligators at least.
Image of alligator eggs and hatchling from National Park Service.
Researchers from the University of Manchester, University of North Texas - Denton, and the Rockefeller Wildlife Refuge - Grand Chenier, Louisiana teamed up to explore the effects of exposure to low oxygen on embryonic American alligators (Alligator mississippiensis). Alligator eggs are often laid in nests where oxygen concentrations can reportedly vary between 11-20% (21% is normal atmospheric levels). This is really important as issues related to embryonic development could continue to affect…
dr. dolittle | April 6, 2016
Still going strong...here are the highlights from several sessions held on Day 4:
Drawing of Lake Whitefish by William Converse Kendall - Kendall, William Converse, b. (1909) Fishes of the Connecticut Lakes and Neighboring Waters, with Notes on the Plankton Environment, Report of the Commissioner of Fisheries, 1906-1907, Washington, DC: Government Printing Office, p. 39 Fig.1, Public Domain
John Eme (California State University, San Marcos) presented data testing the effects of varying temperatures mimicking overwintering conditions on embryonic development of Lake whitefish. He found…
dr. dolittle | November 24, 2015 Image of chicken egg from Wikimedia Commons.
Turns out the egg is an important phase. A new study published this month in American Journal of Physiology - Regulatory, Integrative and Comparative Physiology looked at what happens in the egg when a chicken fetus was exposed to low oxygen (hypoxia) conditions. In mammals, this can occur as a result of maternal hypoxia, preeclampsia as well as anemia in the fetus resulting in less red blood cells that can carry oxygen. Understanding this is important as restricted fetal growth is associated with an increased risk for developing cardiovascular…
dr. dolittle | March 29, 2015
I was very impressed by the graduate and undergraduate students who presented their research at the Scholander poster competition sponsored by the Comparative and Evolutionary Physiology section of the American Physiological Society this afternoon. I am sure the winner of the competition will be very difficult to select.
Some highlights included:
Bridget Martinez, graduate student at the University of California - Merced whose research focused on hormonal changes that occur with fasting in elephant seal pups. In mammals, food deprivation leads to lower thyroid hormone concentrations, which…
dr. dolittle | January 20, 2015I came across an interesting study published last month in American Journal of Physiology - Regulatory, Integrative and Comparative Physiology on obstructive sleep apnea (OSA), which is a disorder in which the upper airway is repeatedly obstructed during sleep resulting in bouts of intermittent hypoxia (low oxygen concentrations). I had no idea that OSA is more common in postmenopausal as opposed to premenopausal women suggesting that estrogen may help protect from OSA. The sex hormones estrogen and testosterone can increase memory and spatial learning. Therefore a team of researchers from…
dr. dolittle | October 8, 2014 Image from the American Physiological Society's website.http://www.the-aps.org/mm/Conferences/APS-Conferences/2014-Conferences/…
Tuesday was no less exciting than Monday!
Here are some highlights:
I thoroughly enjoyed a session called "Overcoming a Major Physiological Barrier: Adaptation from Saline to Freshwater Habitats" which highlighted the need for several species to shift how they regulate ion balance when they migrate between fresh water (ion absorption from the water) and salt water (ion secretion to the water).
Clements K, Bojarski L, Johnson K, McMillan S, White L, Angert E (Univ…
dr. dolittle | May 8, 2014Here is a neat video that I watched at the David Bruce Undergraduate Poster session at the Experimental Biology conference last week. It describes the amazing physiology of the avian lung and was created by an undergraduate student researcher, Peter Luu for the Physiology Video Contest sponsored by the American Physiological Society. This video won the Viewer's Choice Award:
To see more of the submitted videos, visit the American Physiological Society website.
dr. dolittle | May 1, 2014Day 3 of the Experimental Biology meeting was arguably one of the most exciting for comparative physiology. Here are the highlights from Monday:
Morning Seminars:
Birgitte McDonald from Aarhus University, Denmark presented, "Deep-diving sea lions exhibit extreme bradycardia in long-duration dives." Birgitte and Dr. Paul Ponganis measured the heart rate of California sea lions (Z. californianus) using digital electrocardiogram loggers and found that the heart rate was reduced (bradycardia) during dives along with reduced blood flow to the lungs and periphery. This helps preserve the oxygen…
dr. dolittle | April 18, 2014I am very excited about the upcoming Experimental Biology conference that starts next weekend. I just looked through the Spring newsletter for the Comparative and Evolutionary Physiology section of the American Physiological Society. Check out the exciting programming in comparative physiology at this year's conference:
Monday, April 28
10:30 AM – 12:30 PM
Featured Topic: Abstract-Driven Trainee Session
3:15 PM – 5:15 PM
Featured Topic: Comparative Physiology of Aging and Senescence
Tuesday, April 29
8:00 AM – 10:00 AM
CEPS Symposium: RNAseq Approaches to Understanding Extreme
Physiological…
milhayser | April 30, 2013Dr. Dolittle spent a few days at the Experimental Biology meeting of the American Physiological Society, learning incredible facts about animal adaptability. In the Sunday session, researchers showed that metabolic byproducts called ketones can protect against seizures caused by hyperbaric oxygen therapy, while seal pups, who fast for up to three months once weaned, increase their insulin resistance and become effectively diabetic. Monday taught us that insects lack lungs, instead exchanging gas through tiny valves called spiracles along their abdomen, while a Burmese python, after eating a…
dr. dolittle | April 23, 2013
Today's symposia included a session on "Integrative Cardiovascular and Respiratory Physiology of Non-model Organisms" as well as the August Krogh Distinguished Lecture.
This year's Krogh lecture was given by Dr. Stan Lindstedt from Northern Arizona University. Dr. Lindstedt is arguably best known for publishing work showing that the metabolic rate of an animal is negatively correlated with body mass. In other words, smaller animals have a higher metabolic rate than larger animals. Knowing that relationship could have saved Tusko the elephant from a whopping dose of LSD (1962, prior to the…