Fatty foods may cause cocaine-like addiction

Scientists have finally confirmed what the rest of us have suspected for years: Bacon, cheesecake, and other delicious yet fattening foods may be addictive.

A new study in rats suggests that high-fat, high-calorie foods affect the brain in much the same way as cocaine and heroin. When rats consume these foods in great enough quantities, it leads to compulsive eating habits that resemble drug addiction, the study found.

Doing drugs such as cocaine and eating too much junk food both gradually overload the so-called pleasure centers in the brain, according to Paul J. Kenny, Ph.D., an associate professor of molecular therapeutics at the Scripps Research Institute, in Jupiter, Florida. Eventually the pleasure centers "crash," and achieving the same pleasure–or even just feeling normal–requires increasing amounts of the drug or food, says Kenny, the lead author of the study.

"People know intuitively that there’s more to [overeating] than just willpower," he says. "There’s a system in the brain that’s been turned on or over-activated, and that’s driving [overeating] at some subconscious level."

In the study, published in the journal Nature Neuroscience, Kenny and his co-author studied three groups of lab rats for 40 days. One of the groups was fed regular rat food. A second was fed bacon, sausage, cheesecake, frosting, and other fattening, high-calorie foods–but only for one hour each day. The third group was allowed to pig out on the unhealthy foods for up to 23 hours a day.

They began to eat compulsively, to the point where they continued to do so in the face of pain. When the researchers applied an electric shock to the rats’ feet in the presence of the food, the rats in the first two groups were frightened away from eating. But the obese rats were not. "Their attention was solely focused on consuming food," says Kenny.

In previous studies, rats have exhibited similar brain changes when given unlimited access to cocaine or heroin. And rats have similarly ignored punishment to continue consuming cocaine, the researchers note.

See the original article at CNN.

Japanese researchers develop see-through goldfish

TOKYO (AFP) – First came see-through frogs. Now Japanese researchers have succeeded in producing goldfish whose beating hearts can be seen through translucent scales and skin.

The transparent creatures are part of efforts to reduce the need for dissections, which have become increasingly controversial, particularly in schools.

“You can see a live heart and other organs because the scales and skin have no pigments,” said Yutaka Tamaru, an associate professor in the department of life science at Mie University.

“You don’t have to cut it open. You can see a tiny brain above the goldfish’s black eyes.”

The joint team of researchers at Mie University and Nagoya University in central Japan produced the “ryukin” goldfish by picking mutant hatchery goldfish with pale skin and breeding them together.

“Having a pale colour is a disadvantage for goldfish in an aquarium but it’s good to see how organs sit in a body three-dimensionally,” Tamaru told AFP.

The fish are expected to live up to roughly 20 years and could grow as long as 25 centimetres (10 inches) and weigh more than two kilograms (five pounds), much bigger than other fish used in experiments, such as zebrafish and Japanese medaka, Tamaru said.

“As this goldfish grows bigger, you can watch its whole life,” he said.

Meanwhile another group of researchers who announced in 2007 they had developed see-through frogs said they planned to start selling the four-legged creatures, whose skin is transparent from the tadpole stage.

“We are making progress in their mass-production. They are likely to be put on the market next year,” said Masayuki Sumida, professor at the Institute for Amphibian Biology of Hiroshima University.

Sumida said see-through tadpoles and adult frogs would be available in the first half of next year in Japan for laboratories and schools and as pets, with a price tag expected to be below 10,000 yen (110 dollars) each.

He also wants to sell the creature abroad.

Animal rights activists have pressed for humane alternatives to dissections, such as using computer simulations.

Sumida’s team produced the creature from rare mutants of the Japanese brown frog, or Rena japonica, whose backs are usually ochre or brown. Two kinds of recessive genes have been known to cause the frog to be pale.

While goldfish are easier to keep, frogs are higher forms of life and therefore preferable for experiments, Sumida said.

New Yorkers beware! New cockroach hits the Big Apple

NEW YORK (AFP) – New Yorkers are used to fighting each other for space, but there may be a new contender in town according to a Rockefeller study that appears to have uncovered a new species of cockroach.

“The cockroach is genetically modified. Species don’t differ more than one percent, this cockroach is four percent different, which suggests it is a new species of cockroach,” Professor Mark Stoeckle, an expert on genomics and DNA barcoding at Rockefeller University, told AFP.

“We think that the museums of natural history in Paris or New York could be interested.”

The previously-unidentified creepy-crawly was uncovered as part of a project undertaken by two high-school students, Brenda Tan, 17, and Matt Cost, 18, under Stoeckle’s supervision.

In their roles as “DNAHouse investigators,” the pair trawled New York apartments, stores and street, collecting 217 specimens between November 2008 and March 2009.

They took samples from supermarket food, the remains of an insect found in a box of fruit, a feather from a duster, dried dung and a cockroach and matched DNA sequences using the Barcode of Life Database and GenBank.

The American Museum of Natural History laboratory identified 170 genetic codes, leading the researchers to identify 95 different animal species, including some that were unexpected.

“A feather from a duster yielded ostrich DNA. A delicacy labeled ‘sturgeon caviar’ instead turned out to be from the strange-looking paddlefish. A popular Asian snack was revealed as giant flying squid. Bison DNA was found in a dog biscuit,” the pair wrote on the Rockefeller University website.

In fact, they found that 16 percent of food items were mislabeled, including cheeses labeled sheep’s milk that were actually made of cow’s milk, a potentially dangerous labeling error for those with allergies.

But perhaps the biggest surprise for the researchers was the discovery of “a genetically distinct ‘mystery’ cockroach that might be a new species.”

“By appearance it looks like the American cockroach (Periplaneta americana) but it is genetically different from other American cockroaches in the databases,” the researchers said.

Virus-built Battery Could Power Cars, Electronic Devices

For the first time, MIT researchers have shown they can genetically engineer viruses to build both the positively and negatively charged ends of a lithium-ion battery.

The new virus-produced batteries have the same energy capacity and power performance as state-of-the-art rechargeable batteries being considered to power plug-in hybrid cars, and they could also be used to power a range of personal electronic devices, said Angela Belcher, the MIT materials scientist who led the research team.

The new batteries, described in the April 2 online edition of Science, could be manufactured with a cheap and environmentally benign process: The synthesis takes place at and below room temperature and requires no harmful organic solvents, and the materials that go into the battery are non-toxic.

In a traditional lithium-ion battery, lithium ions flow between a negatively charged anode, usually graphite, and the positively charged cathode, usually cobalt oxide or lithium iron phosphate. Three years ago, an MIT team led by Belcher reported that it had engineered viruses that could build an anode by coating themselves with cobalt oxide and gold and self-assembling to form a nanowire.

The viruses are a common bacteriophage, which infect bacteria but are harmless to humans.

The team found that incorporating carbon nanotubes increases the cathode’s conductivity without adding too much weight to the battery. In lab tests, batteries with the new cathode material could be charged and discharged at least 100 times without losing any capacitance. That is fewer charge cycles than currently available lithium-ion batteries, but "we expect them to be able to go much longer," Belcher said.

The prototype is packaged as a typical coin cell battery, but the technology allows for the assembly of very lightweight, flexible and conformable batteries that can take the shape of their container.

Last week, MIT President Susan Hockfield took the prototype battery to a press briefing at the White House where she and U.S. President Barack Obama spoke about the need for federal funding to advance new clean-energy technologies. [ed]Let me see if I understand this: they took a virus to the White House?[/ed]

See the full article at Science Daily.