‘A New Antibiotic That Resists Resistance’

Some time ago I noted the dangers of bacteria becoming increasingly resistant to antibiotics, to the point where some are now “pan-resistant”. In other words, untreatable with existing antibiotics. Those dangers assuredly still exist but a few days ago a bit of good news arrived for a change.

More [classes of antibiotics], hopefully, are coming. A team of scientists led by Kim Lewis from Northeastern University have identified a new antibiotic called teixobactin, which kills some kinds of bacteria by preventing them from building their outer coats. They used it to successfully treat antibiotic-resistant infections in mice. And more importantly, when they tried to deliberately evolve strains of bacteria that resist the drug, they failed. Teixobactin appears resistant to resistance.

Bacteria will eventually develop ways of beating teixobactin—remember Orgel—but the team are optimistic that it will take decades rather than years for this to happen. That buys us time.

via A New Antibiotic That Resists Resistance – Phenomena: Not Exactly Rocket Science

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Doctors Tell All—and It’s Bad | The Atlantic

Fascinating piece about how badly the practice of medicine in the US has lost its way.

In the course of our lives, most of us will urgently need care, sometimes when we least expect it. Currently, we must seek it in a system that excels at stripping our medical shepherds of their humanity, leaving them shells of the doctors and people they want to be, and us alone in the sterile rooms they manage. What makes our predicament so puzzling, and what may offer hope, is that nearly all of us want a different outcome. I used to think that change was necessary for the patient’s sake. Now I see that it’s necessary for the doctor’s sake, too.

The US spends almost twice as much of GDP on health care as most comparable nations and yet “the US ranks last among 11 major industrialised nations in efficiency, equity and “healthy lives”, meaning health outcomes attributable to medical care”. It’s an astonishing record, one that suggests preternaturally perverse systemic incentives.

Still, none of that’s news. What was is just how disastrous the system has also been for the well-being of most of its practitioners.

Today’s physicians, he tells us, see themselves not as the “pillars of any community” but as “technicians on an assembly line,” or “pawn[s] in a money-making game for hospital administrators.” According to a 2012 survey, nearly eight out of 10 physicians are “somewhat pessimistic or very pessimistic about the future of the medical profession.” In 1973, 85 percent of physicians said they had no doubts about their career choice. In 2008, only 6 percent “described their morale as positive,” Jauhar reports. Doctors today are more likely to kill themselves than are members of any other professional group.

The Fat Drug | NYTimes.com

American kids are prescribed on average about one course of antibiotics every year, often for ear and chest infections. Could these intermittent high doses affect our metabolism?

To find out, Dr. Blaser and his colleagues have spent years studying the effects of antibiotics on the growth of baby mice. In one experiment, his lab raised mice on both high-calorie food and antibiotics. “As we all know, our children’s diets have gotten a lot richer in recent decades,” he writes in a book, “Missing Microbes,” due out in April. At the same time, American children often are prescribed antibiotics. What happens when chocolate doughnuts mix with penicillin?

The results of the study were dramatic, particularly in female mice: They gained about twice as much body fat as the control-group mice who ate the same food. “For the female mice, the antibiotic exposure was the switch that converted more of those extra calories in the diet to fat, while the males grew more in terms of both muscle and fat,” Dr. Blaser writes. “The observations are consistent with the idea that the modern high-calorie diet alone is insufficient to explain the obesity epidemic and that antibiotics could be contributing.”

via The Fat Drug – NYTimes.com.

A Post-Antibiotics Future? | Maryn McKenna

Most of us know that bacteria can develop resistance to antibiotics: hardly surprising given their generational cycles can be as short as 20 minutes.

What’s not so well known is that this process is now leading us (seemingly inexorably) towards a crisis. Already, many bacterial infections are resistant to all but one or two types of antibiotics, some are even “pan-resistant”. In other words, untreatable with current drugs:

In 2009, three New York physicians cared for a sixty-seven-year-old man who had major surgery and then picked up a hospital infection that was “pan-resistant” — that is, responsive to no antibiotics at all. He died fourteen days later. When his doctors related his case in a medical journal months afterward, they still sounded stunned. “It is a rarity for a physician in the developed world to have a patient die of an overwhelming infection for which there are no therapeutic options,” they said, calling the man’s death “the first instance in our clinical experience in which we had no effective treatment to offer.”

Because the reliable life cycle of new antibiotics is often so short, pharmaceutical companies have mostly backed away from developing new variants. It’s too expensive and takes too long. The medical armoury is therefore emptying out and new weapons against infection are (at best) likely to be a long way off.

It doesn’t help that antibiotics have been used so indiscriminately over the years. Resistant bacteria were always inevitable (something that Sir Alexander Fleming emphasised right from the start back in the 1940s) but our carelessness has turbocharged the process. Continue reading

Gut bacteria and obesity | Nature

The team took gut bacteria from four sets of human twins in which one of each pair was lean and one was obese, and introduced the microbes into mice bred to be germ-free. Mice given bacteria from a lean twin stayed slim, whereas those given bacteria from an obese twin quickly gained weight, even though all the mice ate about the same amount of food.

The team wondered whether the gut microbiota of either group of mice would be influenced by mice with one type living in close quarters with animals harbouring the other type.

So the scientists took mice with the ‘lean’ microbiota and placed them in a cage Continue reading

‘The mind . . . in itself can make a heaven of hell, a hell of heaven’

Remarkable article about how our social experience and the way we come to frame our lives influences gene-expression.

I would’ve bet my eyeteeth that we’d get a lot of noisy results that are inconsistent from one realm to another. And at the level of individual genes that’s kind of true—there is some noise there.” But the kinds of genes that get dialed up or down in response to social experience, he said, and the gene networks and gene-expression cascades that they set off, “are surprisingly consistent—from monkeys to people, from five-year-old kids to adults, from Vancouver teenagers to 60-year-olds living in Chicago.”

The principal pathway through which this works appears to be the immune system.

Normally, a healthy immune system works by deploying what amounts to a leashed attack dog. It detects a pathogen, then sends inflammatory and other responses to destroy the invader while also activating an anti-inflammatory response—the leash—to keep the inflammation in check. The lonely Chicagoans’ immune systems, however, suggested an attack dog off leash—even though they weren’t sick. Some 78 genes that normally work together to drive inflammation were busier than usual, as if these healthy people were fighting infection. Meanwhile, 131 genes that usually cooperate to control inflammation were underactive. Continue reading

Enlisting immune systems to fight cancer

The struggle with cancer may be entering a radically new stage.

Last December, at a medical conference in Atlanta, the team presented its results to a rapt audience. The data boiled down to this: Nine out of the 12 patients, including both of the children, had responded to the therapy. Nine out of 12 had grown the engineered T cells in their bodies. Nine out of 12 had experienced some degree of tumor lysis syndrome and had seen their tumors vanish, either partially or completely.

Even more encouraging were the follow-up data on the two early cases of compete remission—patients No. 1, Bill Ludwig, and No. 3, Douglas Olson.

One big question all along has been the durability of the T cells. How long will they stay alive in the blood? Months? Years? Will cancer return in these patients? Doctors don’t know. “I don’t think we’ve proven that we’ve cured anyone,” Porter says. Still, when Ludwig and Olson returned to Philly for their two-year checkups in the fall of 2012, they told doctors they felt great. The team checked their blood. The T cells were still alive, two years after infusion. Cancer undetectable.

“I think of these guys as the first astronauts, right?” says Levine. “They didn’t know what they were getting into. They signed up for something, and it’s wonderful to see how it’s turned out.”“

I mean, I thought it might work,” June says, “but I didn’t think it would work as well as it did.”

via Has Carl June Found a Key to Fighting Cancer? | Philadelphia magazine.