Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Nature’s Solutions

Male hamsters pack on the pounds while females stockpile food for winter

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 hibernation […]

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Secret to safer stem cell therapy or cure for cancer?

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 […]

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Keeping arteries healthy, lessons from seals?

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 […]

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Cartilaginous fish need to regulate sulfate too

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 complex. In a new […]

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Limb regeneration in brittle stars

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 process in brittle stars may lead to […]

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Experimental Biology – Day 3

I LOVE THIS MEETING! DAY 3 included several very interesting comparative physiology sessions. Eldon Braun (University of Arizona) spoke about how birds have a unique way to prevent water loss and thereby dehydration. In mammals, the kidneys are responsible for recovering water from the urine. However when birds are well-hydrated, the urine enters the colon and moves backwards up the gastrointestinal tract to facilitate water reabsorption prior to voiding the […]

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Beware of freezing hearts

Thirteen-lined ground squirrels (Ictidomys tridecemlineatus) are really cute when they hibernate (above). During torpor bouts, their body temperature decreases to a few degrees Celsius and their metabolism drops by as much as 95% with heart rates ranging from only 3-10 beats per minute. These bouts of torpor are interrupted by periodic arousals every couple of weeks during which their metabolism increases as body temperature elevates to 37 degrees Celsius. What is so fascinating is […]

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Wound healing with fish

Researchers in China have discovered that collagen isolated from the skin of tilapia effectively reduce wound healing time in mice. The usefulness of collagen, a major structural protein found in connective tissues, in wound healing has been known. Using fish proteins instead of typical mammalian sources reduces the risk for potential pathogens. Dr. Jiao Sun (Shanghai Jiaotong University School of Medicine) and colleagues isolated collagen from the skin of tilapia […]

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Centipede venom blocks pain more effectively than morphine

Researchers from the Chinese Academy of Sciences and The University of Queensland have discovered a venom from centipedes capable of blocking pain more effectively than morphine! According to the study authors, centipedes have appeared in the fossil records as far back as 430 million years. They are also one of the first land-dwelling creatures to use venom to incapacitate their prey as shown in the image above of a Chinese […]

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Bee Sting Therapy for Multiple Sclerosis

I’m really afraid of bees. I’ve only been stung once, and after 2 seconds of pure torture, I thought the end of the world was approaching. Now I’m reading that there might be a way to use bee venom to help individuals with multiple sclerosis and arthritis… by voluntarily being stung! It sounds crazy, but it’s been shown to help some individuals. This video from National Geographic (https://youtu.be/p245IE6_qf8) shows the […]

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