Looking for a better answer for amputees, researchers have turned to nature’s expert in limb regeneration, the salamander. The human body initially reacts similarly to that of a salamander. We immediately form a scar to prevent the open wound from infections and major blood loss, but our bodies stop there. Unlike the salamanders, we cannot reactivate or naturally form a blastema to regenerate a new limb in a few weeks.
Scientists and engineers at MIT are striving to change the design of artificial limbs which are difficult to use and extremely painful. Their efforts are benefiting from studies on a very curious insect model: the horsehead grasshopper that can move its limbs without relying on any muscles. They studied denervated grasshopper limbs that were flexed at different angles and found that a “passive joint force” moves limbs to their original positions when flexed.
Normally when studying disorders that cause blindness in humans, scientists genetically disable cone-related genes in small animals like mice. Studying nine-banded armadillos would give scientists a much more realistic model to test viable treatment options, such as gene therapy, a method of correcting a genetic disease by replacing defective genes with corrected copies. If gene therapy were able to correct the nine-banded armadillo’s cone-related mutations, it could be adapted to correct forms of human blindness.
Snails respond to stress like mammals do. Similar stress responses in both humans and snails make the snail a perfect animal model for researchers studying this constant factor in our lives. Researchers found that when snails must cope with strenuous and varied stressors, their memory stops working. In the study, snails became stressed when they experienced low levels of calcium, needed for proper shell growth, and when the presence of other snails caused overcrowding.
After the Burmese python gorges on massive quantities of food, its metabolism increases by about 40% and its organs enlarge: its gastrointestinal tract doubles in size, and its heart cells swell by about 40%. No new tissue is generated -- the cells grow in a process called hypertrophy. The enlarged heart of the python is not unlike that of the human athlete, heavily muscled and extremely capable. Despite ingesting immense volumes of fat, the heart of the Burmese python never seems to suffer from plaque buildup.
The study of ferrets has been instrumental in the efforts of researchers to uncover viable treatment options for SARS. Due to the similarity of the lung physiology of ferrets and humans, researchers have been using the ferret model for research into the influenza virus. In recent years, scientists have discovered that ferrets are able to contract SARS. The disease is able to replicate efficiently in the respiratory tracts of ferrets just as it does in that of humans.
Noise-Induced Hearing Loss is largely responsible for irreversible hearing damage. NIHL can be caused by a one-time exposure to a loud sound or continued exposure to high-decibel noises. Researchers at the University of Iowa are now turning to the common fruit fly to study and combat NIHL in humans. The fruit fly is the ideal animal model because the molecular structure of its ear is more similar to humans than that of rats or guinea pigs, meaning tests on fruit flies yield more accurate results.
Scientists found that people who have night blindness also have proteins that do not function properly, and fail to send electrical images from the rods to the brain. This connection between night blindness in horses and humans gives us the opportunity to further investigate the cause of CSNB and how we can treat it in both humans and animals.
The naked mole rat has a very long life span, with some living as long as 32 years, but what makes it unique is its apparent resistance to developing cancer. A team at the University of Rochester first described a process of tumor blockade called early contact inhibition that is present in the naked mole rat but not in any other mammalian species. This process might be part of this rat’s unique tumor busting superpower, effectively protecting it from the rapid cell growth and division that occurs with cancer.
Researchers at the University of Utah tested many toxins in the omaria cone snail’s venom and found that Om1A is unique because it fits tightly into some receptors but not others. This desirable attribute is beneficial because if a drug can be developed to mimic the shape of the toxin, it will be less likely to bind with the wrong receptor and cause unwanted side effects. This slow but steady work will someday hopefully transform the omaria cone snail’s debilitating bite into medicine that gives mobility back to people with Parkinson’s disease.