Tag Archives: journal

Study: Catastrophic declines in wilderness over past 20 years

Researchers reporting in the journal Current Biology show catastrophic declines in wilderness areas around the world over the past 20 years.

They demonstrate alarming losses comprising a tenth of global wilderness since the 1990s – an area twice the size of Alaska and half the size of the Amazon. The Amazon and Central Africa have been hardest hit.

The findings underscore an immediate need for international policies to recognize the value of wilderness areas and to address the unprecedented threats they face, the researchers say.

“Globally important wilderness areas — despite being strongholds for endangered biodiversity, for buffering and regulating local climates, and for supporting many of the world’s most politically and economically marginalized communities — are completely ignored in environmental policy,” says Dr. James Watson of the University of Queensland in Australia and the Wildlife Conservation Society in New York. “Without any policies to protect these areas, they are falling victim to widespread development. We probably have one to two decades to turn this around. International policy mechanisms must recognize the actions needed to maintain wilderness areas before it is too late. We probably have one to two decades to turn this around.”

Watson says much policy attention has been paid to the loss of species, but comparatively little was known about larger-scale losses of entire ecosystems, especially wilderness areas which tend to be relatively understudied.

To fill that gap, the researchers mapped wilderness areas around the globe, with “wilderness” being defined as biologically and ecologically intact landscapes free of any significant human disturbance. The researchers then compared their current map of wilderness to one produced by the same methods in the early 1990s.

This comparison showed that a total of 30.1 million km — around 20 percent of the world’s land area — now remains as wilderness, with the majority being located in North America, North Asia, North Africa, and the Australian continent. However, comparisons between the two maps show that an estimated 3.3 million km — almost 10 percent — of wilderness area has been lost in the intervening years. Those losses have occurred primarily in South America, which has experienced a 30 percent decline in wilderness, and Africa, which has experienced a 14 percent loss.

“The amount of wilderness loss in just two decades is staggering,” according to Dr. Oscar Venter of the University of Northern British Colombia. “We need to recognize that wilderness areas, which we’ve foolishly considered to be de-facto protected due to their remoteness, is actually being dramatically lost around the world. Without proactive global interventions we could lose the last jewels in nature’s crown. You cannot restore wilderness, once it is gone, and the ecological process that underpin these ecosystems are gone, and it never comes back to the state it was. The only option is to proactively protect what is left.”

Watson says the United Nations and others have ignored globally significant wilderness areas in key multilateral environmental agreements and this must change.

“If we don’t act soon, there will only be tiny remnants of wilderness around the planet, and this is a disaster for conservation, for climate change, and for some of the most vulnerable human communities on the planet,” Watson says. “We have a duty to act for our children and their children.”

Study: Potent new drug candidate blocks HIV strains

U.S. scientists say they have created a novel drug candidate that is so potent and universally effective, it might work as part of an unconventional vaccine and could be used in the fight against HIV/AIDS.

The research, which involved scientists from more than a dozen research institutions, was published February 18 online ahead of print by the prestigious journal Nature.

The study shows that the new drug candidate blocks every strain of HIV-1, HIV-2 and SIV (simian immunodeficiency virus) that has been isolated from humans or rhesus macaques, including the hardest-to-stop variants. It also protects against much-higher doses of virus than occur in most human transmission and does so for at least eight months after injection.

“Our compound is the broadest and most potent entry inhibitor described so far,” said Michael Farzan, a TSRI professor who led the effort announced on Feb. 18 by The Scripps Research Institute in Jupiter, Florida. “Unlike antibodies, which fail to neutralize a large fraction of HIV-1 strains, our protein has been effective against all strains tested, raising the possibility it could offer an effective HIV vaccine alternative.”

Blocking a Second Site

When HIV infects a cell, it targets the CD4 lymphocyte, an integral part of the body’s immune system. HIV fuses with the cell and inserts its own genetic material — in this case, single-stranded RNA — and transforms the host cell into an HIV manufacturing site.

The new study builds on previous discoveries by the Farzan laboratory, which show that a co-receptor called CCR5 contains unusual modifications in its critical HIV-binding region and that proteins based on this region can be used to prevent infection.

With this knowledge, Farzan and his team developed the new drug candidate so that it binds to two sites on the surface of the virus simultaneously, preventing entry of HIV into the host cell.

“When antibodies try to mimic the receptor, they touch a lot of other parts of the viral envelope that HIV can change with ease,” said TSRI research associate Matthew Gardner, the first author of the study with Lisa M. Kattenhorn of Harvard Medical School. “We’ve developed a direct mimic of the receptors without providing many avenues that the virus can use to escape, so we catch every virus thus far.”

The team also leveraged preexisting technology in designing a delivery vehicle — an engineered adeno-associated virus, a small, relatively innocuous virus that causes no disease. Once injected into muscle tissue, like HIV itself, the vehicle turns those cells into “factories” that could produce enough of the new protective protein to last for years, perhaps decades, Farzan said.

Data from the new study showed the drug candidate binds to the envelope of HIV-1 more potently than the best broadly neutralizing antibodies against the virus. Also, when macaque models were inoculated with the drug candidate, they were protected from multiple challenges by SIV.

“This is the culmination of more than a decade’s worth of work on the biochemistry of how HIV enters cells,” Farzan said. “When we did our original work on CCR5, people thought it was interesting, but no one saw the therapeutic potential. That potential is starting to be realized.”

In addition to Farzan, Gardner and Kattenhorn, authors of the study, “AAV-expressed eCD4-Ig provides durable protection from multiple SHIV challenges,” include Hema R. Kondur, Tatyana Dorfman, Charles C. Bailey, Christoph H. Fellinger, Vinita R. Josh, Brian D. Quinlan, Pascal Poignard and Dennis R. Burton of TSRI; Jessica J. Chiang, Michael D. Alpert, Annie Y. Yao and Ronald C. Desrosiers of Harvard Medical School; Kevin G. Haworth and Paula M. Cannon of the University of Southern California; Julie M. Decker and Beatrice H. Hahn of the University of Pennsylvania; Sebastian P. Fuchs and Jose M. Martinez-Navio of the University of Miami Miller School of Medicine; Hugo Mouquet and Michel C. Nussenzweig of The Rockefeller University; Jason Gorman, Baoshan Zhang and Peter D. Kwong of the National Institutes of Health; Michael Piatak Jr. and Jeffrey D. Lifson of the Frederick National Laboratory for Cancer Research; Guangping Gao of the University of Massachusetts Medical School; David T. Evans of the University of Wisconsin; and Michael S. Seaman of Beth Israel Deaconess Medical Center.

The work was supported by the National Institutes of Health through multiple grants.

Gay teens subject to harsher punishments

Gay, lesbian and bisexual teenagers in the United States are far more likely to be harshly punished by schools and courts than their straight peers, even though they are less likely to engage in serious misdeeds, according to a study published in the medical journal Pediatrics.

“Gay, lesbian and bisexual kids are being punished by police, courts and by school officials, and it’s not because they’re misbehaving more,” said Kathryn E. W. Himmelstein, the study’s lead author. She began the research as an undergraduate student at Yale.

The findings were based on a national sample of more than 15,000 middle and high school students. Researchers asked young people about alcohol abuse, lying to parents, shoplifting and vandalism, along with such serious crimes as burglary and selling drugs.

The survey found that LGB youth were slightly more likely to report minor and moderate nonviolent misbehavior than their straight peers, but less likely to engage in serious crimes. But they were far more likely to be stopped by the police, arrested or convicted of a crime.

In addition, teenagers who said they had experienced feelings of same-sex attraction were more likely to have been expelled from school than other students.

Girls who labeled themselves as lesbian or bisexual appeared to be at highest risk for punishment, experiencing 50 percent more police stops and about twice the risk of arrest and conviction as heterosexual girls who reported similar levels of misconduct.

 

Pride and patient

Dr. Sandeep Kapoor, one of three defendants on trial for conspiring to provide excessive drugs to Anna Nicole Smith, noted in a personal journal that he and Smith partied during a gay Pride parade. The journal entries were introduced as evidence in the Los Angeles trial of Kapoor, who wrote of blurring the lines between doctor and patient and worried, “Can she ruin me?” Drugs, no doubt, ruined Smith’s life, who died of an overdose in 2007.