Life Science
dr. dolittle | July 16, 2016 By Sun Ladder - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10959166
A new study published in Current Biology presents data showing that persistent exposure to artificial lights causes mice to age prematurely. Not only did exposure to bright light alter circadian rhythm, mice living in 24 hour light lost bone density and developed inflammation and weakness in their muscles. Humans are not immune to the effects of disrupted circadian rhythms. In fact, people who work the night shift are reportedly more likely to develop breast cancer, loss of bone mineral density…
dr. dolittle | July 15, 2016Ducklings are rather well-known for their ability to imprint on someone (usually their mother) or something shortly after hatching. Researchers at the University of Oxford were interested in understanding more about learning and memory in ducklings. Specifically, they wanted to know if a duckling simply remembered what they saw or if they were capable of more complex cognition involving determining whether objects had the same or different qualities.
After hatching, they placed ducklings in an enclosed space that contained either identical or different red shapes attached to a string that…
dr. dolittle | July 12, 2016 Image of a Gulf toadfish, Opsanus beta, from Wikimedia Commons
Teleost fish living in saltwater environments are constantly compensating for water loss. This happens because their surroundings have higher concentrations of salts than their plasma and the rule of thumb in Biology is: water follows salt. Thus these fish must somehow compensate for water loss in order to prevent dehydration. One way they do this is by drinking a lot of water. Ions are then removed from the water in the intestines which creates a gradient for water absorption into the body. A new study published in the…
dr. dolittle | July 12, 2016Researchers at Stanford University have accomplished what was once considered impossible. They have partially restored vision in blind. Check out this Youtube video to see how they did it
dr. dolittle | July 9, 2016 Image of common hamster by katanski - Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=10550799
During hibernation common hamsters (Cricetus cricetus) alternate their time between bouts of torpor during which their metabolic rate drops and body temperature is low and arousal during which body temperature is normal. Hibernation allows animals to conserve energy although it is not without costs as it often results in memory deficits, cell damage and reduced immune function. Thus some studies have suggested that animals with sufficient food stores will not undergo…
dr. dolittle | June 28, 2016 Image of a naked mole rat By Roman Klementschitz, Wien - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=252701
Researchers trying to find cures for cancer find naked mole rats rather interesting. Not only are these animals long-lived by rodent standards, they are also resistant to the development of cancer. By long-lived, we are talking up to 30 years! A team of researchers from Hokkaido University and Keio University in Japan have now isolated stem cells from the skin of naked mole rats and induced them to revert back to pluripotent stem cells, the type capable of…
dr. dolittle | June 28, 2016
Skeletal muscle function and structure change as we age. Humans typically experience a loss of muscle mass or muscle weakness which can greatly reduce mobility and stability. While much is known about aging skeletal muscle in humans and rodents, less is known about horses, which are rather athletic animals that are living longer due to advancements in veterinary care and retirement programs. Researchers from the University of Florida decided to explore how aging effects skeletal muscles of horses. To do this, they examined gluteus medius (speed and locomotion) and triceps brachii (mainly…
dr. dolittle | June 20, 2016
Image of hooded seal from NOAA Fisheries (File:Hooded seal.JPG) [Public domain], via Wikimedia Commons
Heart rate decreases during diving in seals and other animals. Thus the ascending aorta becomes very important during diving as it helps to maintain blood pressure during prolonged dives. A new study published in the American Journal of Physiology - Regulatory, Integrative and Comparative Physiology was designed to examine the ascending aorta of hooded seals (Cystophora cristata) and the tiny blood vessels that supply nutrients to it, called the vasa vasorum.
The ascending aorta of the…
dr. dolittle | June 20, 2016 Image of banana shark by Watermeloncat2.0 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=47324709
I LOVE Shark Week on Discovery Channel. I can't wait to see the bizarre sharks episode. The excitement begins June 26th.
dr. dolittle | June 20, 2016Birds get such a bad rap when it comes to intelligence. Sure they have relatively small brains, but scientists have known they are similar to primates with respect to their cognitive abilities. New research published in the Proceedings of the National Academy of Sciences presents data showing how this apparent dichotomy is possible. They found that the brains of songbirds and parrots pack two times the number of neurons as a primate of similar size. This means that these birds are able to pack neurons more tightly than mammals, which allows them to fit more brain cells in a smaller package.…
dr. dolittle | June 18, 2016
The blue blood of horseshoe crabs contains a special chemical limulus amebocyte lysate (LAL) that medical laboratories obtain from thousands of animals annually to detect bacterial infections in humans. The labs are only allowed to draw up to 30% of their blood once a year. Despite these precautions, researchers are becoming increasingly concerned that some animals may be injured during the process resulting in the death of animals after they are returned to the ocean. In fact, some researchers are pushing to add horseshoe crabs to the vulnerable list as populations decline in some countries…
dr. dolittle | June 14, 2016 Image of a spiny mouse. Credit: Clive Druett/Getty
Although laboratory rodents are used to study estrogen-related disorders, they are different from humans in that they do not menstruate. Therefore, they are not used to understand or develop treatments for disorders related to menstruation, like endometriosis, premenstrual syndrome (PMS) or some fertility disorders.
Researchers from Monash University (Australia), have now reported they've discovered a rodent that actually has a menstrual cycle similar to humans. The spiny mouse (Acomys cahirinus) has about a nine day cycle that includes…
dr. dolittle | June 7, 2016Mosquitoes. That's right, mosquitoes. As creepy little transmitters of diseases such as the current Zika virus epidemic (linked with causing the birth defect microencephaly), West Nile virus, malaria, chikungunya, and dengue fever, mosquitoes kill over 1 million people every year according to the World Health Organization.
This fascinating video from PBS shows how they suck your blood:
I am using insect repellent this summer after watching that video!
dr. dolittle | May 27, 2016In a prior post summarizing the annual Michigan Physiological Society Meeting, I briefly mentioned the work from Adrian Vasquez, Milad Qazazi, Andrew Failla, Sanjay Rama, Samuel Randall, and Jeffrey Ram from Wayne State University, Detroit, MI).
They were exploring the diversity of water mites, a type of arachnid, in Western Lake Erie and they found a mixture of both native and invasive species.
Dr. Jeffrey Ram, Professor at the School of Medicine at Wayne State University, was kind enough to share images from their work. They refer to these particular water mites as "charismatic microfauna"…
dr. dolittle | May 25, 2016 Image of elephant fish by fir0002 | flagstaffotos.com.au Canon 20D + Tamron 28-75mm f/2.8 - Own work, GFDL 1.2, https://commons.wikimedia.org/w/index.php?curid=864471
Seawater contains sulfate concentrations that are nearly 40 times those measured in plasma. Therefore, it is easy to see why fish would need to develop mechanisms to keep sulfate within a physiologically normal range. The kidneys of teleost fish have been known to excrete excess sulfate in the urine. However until now, it was not known whether the kidneys of cartilaginous fish do the same thing as their kidneys are rather…
dr. dolittle | May 24, 2016 Chick image By Markus Koljonen (Own work) [CC BY-SA 3.0] via Wikimedia Commons
New research published in the American Journal of Physiology Regulatory, Integrative and Comparative Physiology shows that bacterial infections increase the production of nitric oxide in chicks, which is similar to what happens in rodents. The increase in nitric oxide is thought to be related to the development of fever. In fact, when nitric oxide production was blocked, thermogenesis was inhibited and infected chicks began to huddle more to increase body temperature.
Source:
Dantonio V, Batalhão ME, Fernandes…
dr. dolittle | May 18, 2016
The Michigan Physiological Society, a chapter of the American Physiological Society, held their 3rd annual meeting last week. As mentioned in a prior post, the keynote address was given by Comparative Physiologist Dr. Hannah Carey (University of Wisconsin School of Veterinary Medicine). You can read about her research in the prior post.
Here are other highlights from the meeting:
Seminars:
Photo of crayfish by "Krebse in Österreich", own work, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=858592
...or as I prefer to view them:
Image of crayfish dinner By Игоревич (Own work…
dr. dolittle | May 5, 2016
I am very excited about the upcoming 3rd annual Michigan Physiological Society Meeting on May 12-13 in Detroit. This society is a local chapter of the American Physiological Society. I am most excited by their choice of a Comparative Physiologist for the keynote address: Dr. Hannah V. Carey from the University of Wisconsin School of Veterinary Medicine. Dr. Carey is a Past-President of the American Physiological Society. She will be presenting her research on how the gut microbiome of hibernators changes seasonally as well as the symbiotic relationship between the gut microbes and the host.
dr. dolittle | May 4, 2016Check out this video from Scientific American discussing how canids from different areas have different 'dialects':
dr. dolittle | April 30, 2016 Image of brittle star by Jerry Kirkhart from Los Osos, Calif. [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
A new study published in Frontiers in Zoology examined the developmental process involved in regulating limb regeneration in brittle stars (Amphiura filiformis) following amputation of an arm. Limb regeneration is a multi-stage process involving initial healing and repair of the wounded site, initial growth of the limb followed by development of more complex layers of cells until ultimately the limb has been fully regenerated. Understanding this…