Shiga toxin is nasty stuff. If you are infected with a Shiga-producing bacterium, like Shigella dysenteriae or some E. coli strains, there is no clear treatment: if you are given antibiotics, your infected cells will explode, spraying the toxin all over neighboring cells and exacerbating your symptoms. Each year, 150 million people are infected with Shiga-producing bacteria, which cause dysentery and food poisoning, and a million of those die. The lack of effective treatment for such Shiga toxicosis infections is one of the main reasons this year’s outbreak of E. coli poisoning in Europe was so deadly, with more than 3,700 people infected and 45 dead. But now scientists studying how the toxin makes its way around the cell have discovered that treating mice with the metal element manganese makes them resistant to Shiga poisoning. Since manganese’s chemistry is already well understood and it’s readily available, the possibility of using it as a treatment is exciting.
Here’s how manganese blocks Shiga’s spread, according to the group’s experiments in cultured human cells:
A recent column by Dr. Pauline Chen at the New York Times explores a surprising oversight in modern healthcare: Doctors don’t really have a clue how to predict how long a patient will live. In the absence of a widely accepted, systematic method of prognosis, they’re kind of making it up—an informed guess, with the benefit of education and experience, but a guess nonetheless.
Prognosis was once a diligently studied, widely practiced part of a physician’s job, Chen writes. But as treatments improved, and keeping patients alive longer became ever more possible, the unpleasant but necessary skill of predicting when patients might die fell by the wayside. A recent study, she reports, revealed just how much:
Over the past few years, several studies have illuminated some of what happened during the brief period when modern humans and Neanderthals overlapped in Europe, with genetic analyses showing that the two groups interbred tens of thousands of years ago (though not frequently) and ancient remains suggesting that modern humans fought and—more controversially—ate their prominent-browed contemporaries.
It seems that humans and Neanderthals made occasional love and intermittent war, but what were those interludes of interaction actually like? What was going on inside those distinctive crania? It’s a tricky question to answer—behavior doesn’t fossilize—but anthropologist Thomas Wynn and psychologist Frederick L. Coolidge combine genetic and anthropological evidence with a healthy dose of well-informed speculation to offer an intriguing picture of how Neanderthals may have lived, thought, felt, and acted.
Artist’s rendering of a mitochondrian, the energy-producing
cellular structure affected by ARSACS
Scientists have pinpointed the cause of a rare, fatal neurodegenerative disorder called ARSACS, or autosomal recessive spastic ataxia of Charlevoix-Saguenay. The disease is due to defects in neuron’s mitochondria, the bit of biological machinery that generates energy for the cell—a structure known to be affected in Parkinson’s, Alzheimer’s, and other neurological diseases, as well.
ARSACS was first observed in the descendants of a small group of 17th century French settlers who made their homes near the Charlevoix and Saguenay rivers in what is now Quebec, and has since been seen worldwide. But its incidence remains unusually high in that particular French Canadian community, with 1 in 1,500 to 2,000 people developing ARSACS and 1 in 23 people unaffected genetic carriers of the disease.
When tuberculosis kills lung tissue, it can produce gaping
holes like in the lung on the right.
For a long time, tuberculosis was a gruesome and incurable disease. Antibiotics changed that, but over the last century, as the drugs have been incorrectly used, the tuberculosis bacterium has been developing resistance to them. Multi-drug resistant tuberculosis, which requires a cocktail of many drugs to treat it, has become common. Now Indian doctors have reported in a medical journal that a strain that is resistant to all known drugs for tuberculosis has appeared in Mumbai. Twelve patients so far have been diagnosed with the strain, and it’s likely that they are just the tip of the iceberg in terms of those infected.
There are at least as many planets in the galaxy as there are stars. And even that is probably a vast underestimate.
That’s the latest bombshell from astronomers looking for planets beyond our solar system. Phil Plait at Bad Astronomy will have a post on this soon, but for now, here’s a little quote salad for you:
“Planets are like bunnies; you don’t just get one, you get a bunch,” said Seth Shostak, a senior astronomer at the SETI Institute who was not involved in this research. “So really, the number of planets in the Milky Way is probably like five or 10 times the number of stars. That’s something like a trillion planets.” (via PopSci)
Across the US, this winter has been unusually balmy, with precious little snow, or even rain, and with trees taking the warmth as a cue to send out new leaves in January. Temperature data support those impressions: in the first week of the year, temperatures were 40 degrees F higher than average in some parts of the Midwest, Discovery News reports, and snow cover is at 19 percent across the country, compared to an average of 50 percent at this time of year. In notoriously chilly Fargo, North Dakota, the January 4 high temperature of 55 broke the record for the warmest January day on record, and the country has seen close to no rain or snow in this first week of 2012, writes Wunderground meteorologist Jeff Masters. “It has been remarkable to look at the radar display day after day and see virtually no echoes,” he writes, referring to the radar echoes reflected back by storms. “It is very likely that this has been the driest first week of January in U.S. recorded history.”
Why this freaky weather? The answer is, basically, an extremely unusual jet stream over the last few months, Masters explains. The jet stream that defines weather in North America is controlled by the North Atlantic Oscillation and the Arctic Oscillation, climate patterns that reflect differences in sea-level pressure across certain stretches of the globe. And the pressure differences this year have been tremendous—for the North Atlantic Oscillation (NAO), this year saw the most extreme difference ever recorded in December, and the second most extreme for the Arctic Oscillation (AO).
Archaeologists, historians, and governments take great care to preserve human history across the globe, protecting monuments of our civilizations and traces of our origins. Even what may seem, at first, like the detritus of existence—footprints left millions of years ago, the contents of well-preserved wastebins—can serve as tangible, informative links to the past.
Now, scientists and officials are working preserve some of humanity’s best-known footprints, left by a giant leap for mankind, by extending those same sorts of historical protections to the Apollo missions’ lunar landing sites. The tricky part is, many such protections require that a site be on the territory of a state or nation—and the US government can’t claim sovereignty over any part of the moon, and doesn’t want to appear as though it’s trying to. But NASA and the New Mexico and California state governments have gotten onboard with the effort to safeguard the sites, spearheaded by New Mexico State University anthropologist Beth O’Leary. A NASA panel recently issued recommendations for protecting the sites that suggest future explorers give a wide berth to the astronautical artifacts left behind, Kenneth Chang reports at the New York Times:
How a living material of cheese fungi sandwiched between plastic sheets works.
The crusty rind of cheeses like Camembert provide more than texture: they are miniature fortress walls, made of fungus, that protect the cheese’s creamy insides from bacterial invasions. Now, taking inspiration from this delicious snack, chemical engineers at ETH Zurich in Switzerland have shown that such a fungus can be enclosed in porous plastic and will digest spills, with implications for creating antibacterial surfaces from living material.
The team sandwiched a layer of Penicillium roqueforti—from, you guessed it, Roquefort cheese—between a plastic base and a top sheet of plastic with nanoscale pores that allowed gas and liquids to move through, but did not allow the fungus to spread. Then, they mimicked a kitchen spill by pouring sugary broth on the surface and watched as, over the course of two weeks, the captive fungus gradually consumed the entire spill, leaving the surface clean. As shown in the figure above, the fungi can go dormant when there is no food around, so if one had a countertop of such a material, you wouldn’t need to keep spilling sugar on it to keep the fungi happy. Read More
If you could watch a movie of the planet over the last several million years, you’d see the ice caps advance and retreat: The planet’s climate moves in cycles, with ice ages and interglacial periods alternating. But looking at previous interglacials similar to our own, geophysicists now think that the current mostly ice-less period may be longer than it would have been had a certain species not invented the combustion engine. Specifically, it looks like with amount of greenhouse gases we’ve already spewed into the atmosphere, the next ice age will be delayed. And before you decide that’s a good thing, at the rate we’re currently going, we’re not just pushing off the glaciers for a few geologically insignificant years: the team says that the atmospheric concentration of CO2 would to be at most 240 parts per million (ppm) before glaciation would kick in. Right now, it’s 390 ppm, with no signs of dropping and many signs of continuing to rise. When (and how) the planet’s self-regulation system will kick in isn’t clear, but the long, increasingly hot trip probably isn’t going to be pretty.
Read more at the BBC.
Image courtesy of NASA / Wikipedia