News

Your doctor gives you a choice: prolonged life or rapid decline. If you are an abuse victim, a recent National Institutes of Health-funded study indicates, you might choose decline.

David W. Pantalone, a clinical psychologist at Suffolk University, studied 171 HIV-positive gay men. Each month, abused men skipped nearly 20 percent of their HIV medications. Pantalone links statistically abuse, psychological distress, and poor physical health.

“The world dichotomizes mental and physical health, but we know that isn’t really so,” Pantalone says. He looked at interpersonal violence, such as child and partner abuse and tied this violence to mental health: symptoms of depression, anxiety, and posttraumatic stress disorder. Then, using a 700-question survey and data pulled directly from participants’ electronic medical records, he measured physical health by looking at the frequency of emergency room visits, reports of physical injury and chronic pain, and missed HIV medication doses. read more »

Researching climate in the Arctic, an international team of geochemists has finally hit pay dirt.

Digging up layers of ancient lake sediment and residue from glacial ice, they have pieced together a detailed temperature history of the Arctic over the last two thousand years.

Close analysis of these sediments has confirmed scientists’ suspicions that the Arctic had slipped into a long cooling phase at the turn of the first century A.D. Summer temperatures dipped steadily lower, decade-by-decade, until the nineteenth century as the industrial revolution took hold. The Arctic then began to warm, the study says, and has been warming steadily since.
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Bo Obama, a Portuguese Water Dog

“Westminster. There’s only one.” That’s the slogan for America’s most prestigious dog show. Yet despite all the distinctive dog coats that will trot through Madison Square Garden this February, when it comes to the genes responsible, there are only three.

Researchers at laboratories including the National Institutes of Health and the University of Utah have linked ninety-five percent of dog coat variations to these few simple genes.

“Each of our 161 recognized breeds has what’s called a standard, including coat, that describes what an ideal specimen should look like,” says Lisa Peterson, a representative of the American Kennel Club, the governing body for Westminster. For the Portuguese water dog, that standard includes two coat varieties: curly and wavy. “It’s in bold,” says Peterson, reading the judging criteria, “no preference will be given to coat type.”

But for Kevin Chase, a researcher at the University of Utah and coauthor of the study, the Portuguese water dog’s curly-wavy divide proved crucial. Chase describes the two coats as distinct “snapshots” of the dog’s genome. By comparing these snapshots, his team quickly narrowed the cause of this complex trait to the underlying genes.
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The Planet Killer from Star Trek Episode #35
“The Doomsday Machine”

Science fiction gets another chance to get it all wrong.

A study using the Canada-France-Hawaii telescope based in Hawaii confirmed that as the Andromeda galaxy moves through our local cosmic neighborhood, it eats everything in its path—including, eventually, us.

Andromeda grows by pulling galactic companions to it, like spare change down a sewer grate. The astronomers found evidence of this interaction by detecting stars streaming off some dwarf galaxies not fully absorbed by Andromeda. The shape of these streams traces the size and history of the galaxies being pulled in, says MIT astrophysicist Robert Simcoe, and is determined by the mass of the galaxy itself: the larger the galaxy being eaten, the closer the stream will be to its center.

So will Andromeda tear our galaxy apart as it devours us? Not exactly, says Pauline Barmby, one of the study’s authors. read more »

Prostate Cancer is the second most common cancer in men.
Image source: US Nat’l Library of Medicine

Prostate cancer is the second most common cancer in men, affecting one in six American males. But could it also be contagious?

New research indicates that prostate cancer may be among the twenty percent of human cancers associated with infectious disease.

Scientists at Columbia and the University of Utah examined 300 prostate cancer tissue samples and found a virus, known as XMVR, in 23 percent of them and in over 45 percent of the most aggressive cancers.

The virus, xenotropic murine leukemia virus-related virus, is similar to those that cause leukemias and sarcomas in cats, rodents and other primates, but this is the first time such a virus has been observed in malignant human prostate cells. Previous research has suggested that XMVR may be sexually transmitted.
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With their smiling eyes and wagging tails, dogs often make life easier for us. As it turns out, their DNA recently had a similar effect for geneticists. Most of the complex array of coats that dogs wear—from the halo of softness engulfing the Pomeranian and the wiry bristles of a Scottish Terrier to the curls of a spaniel and the sleek jacket of the lab—can be reduced to the influence of just three genes.

The National Human Genome Research Institute in Bethesda, Maryland, headed a study of the coats of over 1,000 dogs from eighty breeds. They noted three traits in each dog: the length of its coat, how curly its coat was, and whether or not it sported the prominent “eyebrows” found on many wiry-haired breeds. Then they hit the labs, analyzing the specific sequence of each dog’s genetic code. When they compared dogs to DNA, they saw that each of the three traits they had observed was governed by its own gene, acting independently from the others. It was the combined influence of the three genes that created the tremendous variation in coats seen among the different breeds.
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Grinnell Glacier at Glacier National Park
Source: Wikimedia Commons

A team of Arctic geochemists recently robbed climate change skeptics of one of their most beloved seeds of doubt—historical ambiguity. Without thousands of years of temperature data, questioners have claimed, how can we know that the Arctic’s recent spate of steamy summers is really a manmade anomaly, and not just a natural hiccup in the region’s climate?

The geochemists’ new study, published in September in the journal Science, provides such data. Through analysis of glacial ice cores, tree rings and Arctic lake sediments, the study’s authors were able to expand the previous 400-year temperature history of the region by an additional 1,600 years. The result is a two millennia-long narrative of the Arctic’s climate that unfurls decade by decade. What surprised scientists in sifting through this new data was the discovery that 2,000 years ago, Earth was in the grip of a cooling trend that seemed determined to plunge the planet into the next Ice Age.

The good news is that through our steadfast combustion of fossil fuels we appear to have thwarted our icy fate. The data show that just a handful of decades after the industrial revolution found its groove, Arctic temperatures stopped sinking and started rising.

The bad news is that since 1950, we’ve experienced five of the six hottest decades with the balmiest one to date ending just last year. “Climate change is itself nothing to be scared of,” says Mark Serreze, a senior research scientist at the National Snow and Ice Data Center. “The issue we’re facing today is the rapid rate of change, with the question now being: Can we adjust?”

Andromeda Galaxy
Image courtesy of John Lanoue, Wikimedia Commons

The current rage in galactic astronomy is “hierarchical formation” — the buildup of big galaxies by devouring little ones — and the Pan-Andromeda Archaeological Survey (PAndAS) is adding fodder to the flame.

Using the 3.6-meter Canada-France-Hawaii Telescope, PAndAS is digging up table scraps from our nearest spiral galaxy neighbor, Andromeda, in the largest single-galaxy survey of its kind. The observations reveal several previously-unobserved star streams spanning tens to hundreds of light-years, likely leftovers from Andromeda’s previous feedings. Hordes of red giant stars also trace a dim structure 100 times larger than the galactic disk we see with our eyes. Because the astronomers do not detect enough gas in the area to form the stars in situ, the stars must be crumbs captured in previous interactions, claims the team’s Nature paper, lead-authored by Alan McConnachie of the Herzberg Institute for Astrophysics in British Columbia.
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Scientists at Stanford University are developing a treatment for cancer that could be one thousand times as potent as drugs available today.

Their study used a sheet of carbon, called “nano” graphene, a fraction of the size of living cells, to transport and deliver a drug potentially deadly to cancer cells. The drug itself had never been used in therapy because it does not dissolve in water.

But neither did graphene at first. Chemists clipped star-shaped “hydrophilic” attachments to the sheet, which splayed outwards from the surface, stabilizing the sheet in water. Vast expanses of “hydrophobic” areas remained on the sheet, now out of reach of water molecules. The new drug, SN38, spontaneously embedded itself on this hydrophobic surface. The complex dissolved.

The drug-sheet complex was tested on colon cancer, ovarian cancer, breast cancer, and glioma cell lines. This test found out how much drug was needed to kill half the available cancer cells in an experiment over seventy-two hours.
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DNA Polymerase Beta
source: Wikimedia Commons

One protein could hinder treatment for over 60,000 African American cancer patients each year.

The death rate for African Americans for all cancers is consistently higher than other cancer patients—18 percent higher for women and 35 percent for men. Although many factors contribute to this disparity, recent results from a lab directed by Joann Sweasy at Yale University indicate that researchers should look closely at a protein called DNA polymerase beta.

Polymerase beta is a naturally occurring enzyme in all humans, but Sweasy’s research indicates that populations originating from Africa may have a different version. “It’s important in terms of the history of human beings and in addressing health disparity questions,” says Sweasy.

Even if you do not smoke and wear suntan lotion, your body’s basic operations, merely processing sugars required for life, can create errors in your genetic code—10 to 20,000 per cell per day. If the errors occur in the wrong place, a normal cell can become a cancer cell and start rapidly producing others like itself. Polymerase beta works as a DNA repairman, finding and correcting these errors.
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Vitamin-D deficient older adults may be at risk for heart disease.

The epidemic of vitamin-D deficiency in the United States may be triggering an epidemic of heart disease, say researchers.

A recent study documenting heart disease and vitamin-D levels in more than 3,400 older adults saw 44 percent of its participants die in seven years, at least 21 percentage points higher than in other similar studies. Even accounting for various causes of death, vitamin-D deficiency was a “very strong predicator of death,” says Dr. Adit Ginde, the study’s lead author.

Vitamin-D deficiency has also been tied to respiratory tract infections and catching the flu in addition to heart disease, which is the leading cause of death in the United States with almost 632,000 victims in 2006.
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Ergot fungus on wheat stalks

Genes can leap between plants and fungi, say a group of British researchers who recently discovered nine such genes that had crossed from one biological kingdom to the other.

This phenomenon, known as horizontal gene transfer, had previously been identified within taxonomic kingdoms. It’s common among bacteria, and genes have even been observed to jump ship from one plant species to another, likely due to sexual accidents associated with their free-drifting pollen.

In fungi, researchers have found that horizontal gene transfer may be responsible for the toxicity of wheat fungus, as well as the ever-popular alcohol-producing metabolisms of wine yeast. The pervasiveness of the process has caused geneticists and evolutionary biologists to recognize its importance as a factor in the evolution of Earth’s biosphere.
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