Life & Non-humans

Researchers Tie Worldwide Biodiversity Threats to Growth in Households

Scientists have revealed evidence that increased numbers of households, even where populations are declining, are having a vast impact on the world’s biodiversity and environment. Reduction in household size has led to a rapid rise in household numbers around the world and has posed serious challenges to biodiversity conservation, write the researchers. Biodiversity is threatened severely not only by increased numbers of households, but also by less efficient per capita consumption of natural resources, the researchers say. They cite examples that larger numbers of households require more use of natural resources for construction, and that smaller numbers of people per household use on average more energy and goods per person.

Mutation in DKC1 Gene Can Cause Rare Aging Disease and Cancer

A rare genetic syndrome, Dyskeratosis Congenita (DC), may hold the key to understanding a mechanism that causes premature aging and cancer. Recreating DC in genetically altered knockout mice, researchers at Memorial Sloan-Kettering Cancer Center and colleagues proved that the disorder was caused, as theorized, by mutations in the DKC1 gene. Unexpectedly, they also showed that DC was caused by a disruption in ribosome function and not due to shortened telomeres (the distal end of a chromosome arm) as previously hypothesized. Their results, published in the January 10 issue of Science, may have implications for development of drugs that kill cancer cells by specifically targeting ribosomes, similar to the way ribosome targets have been key to the development of antibiotics for specific bacterial infections.

Cells Dine on Their Own Brains to Stay Fit

Eating your own brain may not sound like a sensible approach to prolonging your life, but researchers at the University of Rochester have discovered that some single-celled organisms essentially do just that to keep themselves healthy. Scientists studied the yeast Saccharomyces cerevisiae and found that contrary to what biologists have believed, the cell would “eat” its own nucleus to rid itself of aged or damaged sections. Though it’s long been known that cells frequently break down and recycle various cell parts in a process called autophagy (after the Greek for “self-eating”), biologists thought that eating the nucleus was strictly off-limits.

Newly identified enzyme reduces bitterness in cheese

A Wisconsin scientist is using new technology to tackle an old problem in cheesemaking – and the solution could mean both a bigger market for the state’s dairy producers and reduced costs for cheesemakers. One of the major expenses in cheesemaking is the cost of storing cheeses as they age and develop their distinctive flavors, says Jim Steele, a food scientist with the University of Wisconsin, Madison. Cheddar takes six months to a year to mature, while Parmesan takes a full year. During that time off-flavors and bitterness, the most common Cheddar defects, may develop. “We’ve identified an enzyme that plays a critical role in reducing bitterness in cheese,” says Steele. “If the bacteria in the starter culture produced this enzyme cheesemakers would save money and ensure a more consistent product.”

Gulf War chemicals can damage testes, study shows

A combination of chemicals given to protect Gulf War soldiers against deadly diseases and nerve gas may have inadvertently damaged their testes and sperm production, according to animal experiments at Duke University Medical Center. The new study could explain why some veterans have experienced infertility, sexual dysfunction, and other genitourinary symptoms, said Mohamed Abou Donia, Ph.D., a Duke pharmacologist.

Polar bear headed for extinction, says University of Alberta scientist

Unless the pace of global warming is abated, polar bears could disappear within 100 years, says a University of Alberta expert in Arctic ecosystems. While it has been known for some time that the polar bear is in trouble, new research shows that Arctic ice–the polar bear’s primary habitat–is melting much faster than scientists had believed, says U of A biologist Dr. Andrew Derocher. “The climate predictions coming out are showing massive changes in sea-ice distribution,” said Derocher, who follows polar bears to see how they adapt to changing conditions. If the predictions are correct, he says, “we’ll certainly lose polar bears in a lot of areas where we currently have them.” Ice conditions in the Beaufort Sea, for example, are already changing dramatically.

Scientists find first active ‘jumping genes’ in rice

Researchers studying rice genomes have identified the species’ first active DNA transposons, or “jumping genes.” The scientists also discovered the first active “miniature inverted-repeat transposable element,” or “MITE,” of any organism. Rice (Oryza sativa), an important food crop worldwide, has the smallest genome size of all cereals at 430 million base pairs of DNA. About 40 percent of the rice genome comprises repetitive DNA that does not code for proteins and thus has no obvious function for the plant. Much of this repetitive sequence appears to be transposons similar to MITEs. But like most genomes studied to date, including the human genome, the function of this highly repeated so-called “junk DNA” has been a mystery. The discovery of active transposons in rice provides startling new insights into how genomes change and what role transposons may play in the process.

Vitamin C, fish, and a gout drug target artery damage from smoking

Researchers have found that vitamin C and taurine, an amino acid in fish, reversed abnormal blood vessel response associated with cigarette smoking ? a discovery that may provide insight into how smoking contributes to “hardening of the arteries,” according to an Irish study in today’s rapid access issue of Circulation: Journal of the American Heart Association. In a second study, researchers from Iowa demonstrated that a drug used to treat gout ? allopurinol ? rapidly reversed the abnormal blood vessel constriction caused by smoking.

Animals, plants already feeling effects of global warming

Global warming is having a significant impact on hundreds of plant and animal species around the world — although the most dramatic effects may not be felt for decades, according to a new study in the journal Nature. “Birds are laying eggs earlier than usual, plants are flowering earlier and mammals are breaking hibernation sooner,” said Terry L. Root, a senior fellow with Stanford’s Institute for International Studies (IIS) and lead author of the Jan. 2 Nature study. “Clearly, if such ecological changes are now being detected when the globe has warmed by an estimated average of only 1 degree F (0.6 C) over the past 100 years, then many more far-reaching effects on species and ecosystems will probably occur by 2100, when temperatures could increase as much as 11 F (6 C),” Root concluded.

New evidence for orangutan culture

An international collaboration of primatologists has gleaned evidence from decades of observations of orangutans that the apes show behaviors that are culturally based.
The scientists’ findings push back the origins of culturally transmitted behavior to 14 million years ago, when orangutans first evolved from their more primitive primate ancestors. Previous evidence for cultural transmission in chimpanzees suggested an origin of cultural traits 7 million years ago. The researchers also warn that illegal logging and other habitat destruction in the forests of Sumatra and Borneo could not only threaten further research into the earliest origins of culture, but continue the dangerous decline in orangutan populations.

Research finds life 1,000 feet beneath ocean floor

A new study has discovered an abundance of microbial life deep beneath the ocean floor in ancient basalt that forms part of the Earth’s crust, in research that once more expands the realm of seemingly hostile or remote environments in which living organisms can apparently thrive. The research was done off the coast of Oregon near a sea-floor spreading center on the Juan de Fuca Ridge, by scientists from Oregon State University and several other institutions. It will be published Friday in the journal Science.

Lobsters navigate with magnetic positioning system, study shows

Spiny lobsters possess a remarkable navigational sense based on an ability to read small variations in the Earth’s magnetic field, experiments conducted by North Carolina scientists show. The new work is the first to demonstrate that at least some invertebrate animals, which many people consider primitive underachievers biologically, possess navigational skills rivaling those of sea turtles and homing pigeons.

First Virtual Stomach Explores Drug Delivery

Researchers have developed the first virtual stomach, a computer-generated model that is providing unique insights into the way medicines are released from pills and capsules. “There’s no other technique to allow you to see flow patterns in a real stomach, animal or human,” said lead researcher James G. Brasseur, Ph.D., a professor of mechanical engineering and bioengineering at The Pennsylvania State University. Although pills and tablets have become a ubiquitous part of our society, the detail of how the stomach breaks them down to help release their medicine remains unclear. “You can give someone a drug and measure its uptake in tissue,” he said, “but the process between administering the drug and the uptake is largely guesswork.”