Life, Death, and ERVs

In a phenomenon known as Peto’s paradox, large mammals do not develop cancer more often than small mammals, despite having more cells that could go haywire. On Life Lines, Dr. Dolittle writes “Some researchers suggested that perhaps smaller animals developed more oxidative stress as a result of having higher metabolisms. Others proposed that perhaps larger animals have more genes that suppress tumors.” But a new hypothesis argues that large mammals have evolved to minimize the activity of ERVs, which are ancient viral elements integrated into our DNA. Active ERVs can cause cancer and possibly other diseases; mice exhibit about 3300 active ERVs, while humans exhibit about 350. On the blog known as ERV, Abbie Smith writes “some of the young ERVs in humans, the ones that can still code for a protein here and there, are reactivated in HIV+ patients.” Researchers are considering targeting these ERVs in order to combat HIV; as Abbie writes, “You could train the HIV+ individuals immune system to ‘see’ the ERV components in an HIV infected CD4+ T-cell, and BAM! Kill the HIV infected cell!” But she warns that other ERV components are expressed in many normal human cells, and teaching our immune system to target them might be a very bad idea.

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Last Week on ResearchBlogging.org

Scientists use a ‘gene gun’ to insert a gene from a flowering plant called rockcress into the cells of wheat seeds. The genetically modified wheat became more resistant to a fungus called take-all, which in real life can cause “a 40-60% reduction in wheat yields.”

T-cells from six HIV+ patients were removed from their bodies, treated with a zinc-finger nuclease designed to snip a gene out of the cell’s DNA, and put back in the patients.  Removal of the gene mimics a naturally occurring mutation which confers resistance to the HIV virus.  But only 25% of the treated cells showed evidence of being successfully edited.

Researchers “use time-resolved X-ray microtomography to visualize the muscles and hinges in three-dimensions” of fly wings, modelling the complex physical processes that enable flies’ flight.

Even with the cost of building new energy storage infrastructure, wind energy will continue to offer a net gain of power.  Plus: wind produces enough surplus electricity to offer 72 hours of backup power (vs. 24 hours for solar panels).  Researchers say that the industry of onshore wind turbines can “double in size each year—and still maintain an energy surplus.”

Researchers cremated the remains of young piglets to investigate why there’s little evidence of high infant mortality in the archaeological record. To no avail.

Men in ‘traditional’ marriages (whose wives are not employed) are more likely to look negatively upon women in the workplace.

Regardless of the structural integrity of a shoulder (rotator cuff) repair, patients have improved function and reduced pain after surgery.

Stem cells are influenced by the rigidity of the substrate they grew up on: “spending 10 days on a particular bed leads to irreversible future differentiation of the stem cells into stiff-environment-loving bone or soft-loving fat cells.”  That could lead to considerable demand for a new scaffolding material “based on a biocompatible silk-alginate hydrogel” which can be made to varying standards of firmness.

By appearing to tap test subjects on the hand with a small hammer while playing the recorded sounds of a hammer tapping stone, researchers made people feel their hands were more stone-like (or numb).

A gene coincidentally named FAT10 ( for F Adjacent Transcript) actually “regulates lipid metabolism and longevity,” and model mice who lacked the gene were leaner, had a faster metabolism, and lived up to 20% longer.

Encapsulating immature pancreatic cells grown from human stem cells and implanting them under the skin of mice showed the cells could produce insulin whenever needed and reduce diabetic symptoms.

The CDC revised it autism prevalence rate upward again; in 2010 about 1 in 68 eight-year-olds had an autism spectrum disorder.

At age six, children award beneficial resources to members of their ‘in-group;’ at age eight they also assign harmful or negative resources to members of an ‘out-group.’

People with OCD were less likely than controls to believe they could influence a light bulb by pressing a space bar whenever they want. The light bulb blinked randomly on and off.

A virus affecting crickets not only sterilizes them, but makes them more eager to initiate courtship. Males perhaps uninhibited by the virus would start playing a courtship song for a female much sooner than their healthy peers.  Intimacy may be the virus’s way of spreading.

Within the ultrapure water purification system of a nuclear reactor, scientists found oligotrophic bacteria, including new species, growing in biofilms “visible to the naked eye” on ceramic filter surfaces.

Endlessly Adaptable Animals

Dr. Dolittle spent a few days at the Experimental Biology meeting of the American Physiological Society, learning incredible facts about animal adaptability. In the Sunday session, researchers showed that metabolic byproducts called ketones can protect against seizures caused by hyperbaric oxygen therapy, while seal pups, who fast for up to three months once weaned, increase their insulin resistance and become effectively diabetic. Monday taught us that insects lack lungs, instead exchanging gas through tiny valves called spiracles along their abdomen, while a Burmese python, after eating a meal up to 25% of its body weight, develops an enlarged heart to facilitate metabolism. From Tuesday Dr. Dolittle reports the pitfalls of doping elephants with LSD, and that specialized mitochondria supercharge hummingbird wings and rattlesnake tails. There are even more findings about low-oxygen, or hypoxic, adaptations, including turtle shells that prevent lactic acid buildup, and one researcher who raised geese so she could train them to fly in a wind tunnel while wearing gas masks.