Seeing without eyes

A recent discovery has scientists standing in awe of a marine creature that can see through its skin.

The brittle star, or Ophiocoma wendtii, can respond to light despite lacking eyes and a brain. Previous studies argued that merely responding to light does not fit the scientific definition of “vision.” But a study published in Current Biology on Jan. 2 shows that the creature not only reacts to changes in light but also can discern shapes, a clear indication of vision.

Brittle stars live in the bright, complex coral reefs of the Caribbean Sea and the Gulf of Mexico. They change color from deep red during the day to beige at night. The species first caught researchers’ attention 30 years ago, when they discovered tiny crystal bumps that allow it to detect light and see shadows through its skin cover its entire body.

During the recent experiment, the animals sought out areas of contrast that mimicked coral structures, which offer shelter from predators. The scientists also found that during the day the red pigment narrowed the angle of light that could reach the sensors. A wider angle would cause blurring and make vision impossible.

The brittle star defies evolutionary explanations of its origins. According to Frank Sherwin, a zoologist with the Institute for Creation Research and author of The Ocean Book and Guide to Animals, fossils of brittle stars suddenly appeared in sedimentary rock layers as fully formed animals with no evidence of evolving from any lower life form.

“Non-evolutionary zoologists agree with evolutionists, the features and design of Ophiocoma’s ‘visual skin’ is not only strange and mysterious, but also astonishing, incredible,” Sherwin wrote on the institute’s blog. “However, creationists give glory to the Creator, not the creation.”

Researchers hope they can one day learn to imitate the design of the brittle star’s visual system.

“Sensing the environment and responding to a stimulus without having to wait for that signal to go all the way to the brain can save a lot of time,” Julia Sigwart, an evolutionary biologist at Queen’s University Belfast, told Nature. She said it could inspire the development of faster robots and image-recognition technology that doesn’t rely on a central control system.

Drilling deadly bacteria

A team of American scientists has come up with a creative response to superbugs, or bacteria that have developed antibiotic resistance. It is estimated that superbugs could kill an estimated 10 million people a year over the next 30 years, outpacing cancer deaths. “These are nightmare bacteria; they don’t respond to anything,” James Tour, a chemist at Rice University, said in a statement.

But Tour and a team of U.S. researchers may have discovered a way to thwart this ever-growing threat. In a study published Dec. 9 in the American Chemical Society journal ACS Nano, the scientists developed motorized molecules that act as tiny drills. When the scientists activate the molecules with light, they spin at 3 million rotations per second, enabling them to drill holes into the exterior walls of these deadly bacteria.

When bacteria develop a resistance to antibiotics, they often lock the medication out. But the microbes possess no defense against the mechanical rather than chemical action of the nano-drills. Once the molecules burrow holes into the walls of the bacteria, the antibiotics can get inside and kill the microbe in minutes.

“This can breathe new life into ineffective antibiotics by using them in combination with the molecular drills,” Tour said.

In trials, the researchers killed 94 percent of a pneumonia-causing pathogen. The scientists foresee initially using the molecular drills to treat a variety of bacterial infections.

“On the skin, in the lungs or in the GI tract, wherever we can introduce a light source, we can attack these bacteria,” Tour said. “Or one could have the blood flow through a light-containing external box and then back into the body to kill blood-borne bacteria.” —J.B.

Mysterious virus tied to market in China

Fifty-nine people in Wuhan, China, have contracted a mysterious pneumonia-type viral disease. Authorities in the city of 11 million located 430 miles west of Shanghai ruled out acute respiratory syndrome (SARS), Middle East Respiratory Syndrome (MERS), influenza, avian flu, and adenovirus as the cause. No deaths have been reported so far, but some people remain critically ill.

Everyone who contracted the disease had come in contact with a market that sells seafood, game animals, the organs of rabbits and other wildlife, and live animals, including birds and snakes. Some are concerned a previously unknown virus may have begun to jump from animals to humans, University of Hong Kong microbiologist Yuen Kwok Yung told Science Magazine. Officials haven’t found any cases of someone catching it from another person.

Due to China’s advances in infection control and diagnostic capabilities, “it is highly unlikely that this outbreak will lead to a major [SARS-like] epidemic, though we cannot be complacent!” Yung said. —J.B.

Hope for Alzheimer’s patients

In the next two years, scientists hope to begin human trials on a vaccine created to prevent dementia. The vaccination is made up of a combination of drugs designed to remove the brain plaque and tau protein aggregates associated with Alzheimer’s disease, according to a paper published on Dec. 31 in the journal Alzheimer’s Research & Therapy.

In animal studies, the vaccine reduced cognitive decline in mice engineered to manifest the early stages of Alzheimer’s. The disease is the leading cause of age-related dementia and affects about 5.7 million people in the United States. —J.B.