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Microbes May Slim Us Down After Gastric Bypass - ScienceNOW - 0 views

  • In many people with type 2 diabetes, the disease vanishes almost immediately after surgery, too quickly to be explained by the gradual weight loss that happens later
  • Patients also describe not being as hungry, or craving foods like salad that they hadn't liked much before
  • Because it bypasses part of the stomach and small intestine, the surgery alters the intestinal environment, changing elements such as pH and bile concentrations
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  • Another important question
  • is whether the transplants will have the same effect in animals who weren't raised in a sterile environment and who already have their own gut microbiome
  • These animals would more closely mimic people undergoing gastric bypass surgery
Mars Base

Gut microbes may be behind weight loss after gastric bypass | Genes & Cells | Science News - 0 views

  • Roux-en-Y, the most common technique for gastric bypass, diverts food around most of the stomach and upper small intestine
  • Previous studies of people and rats have found that the natural mix of microbes in the intestines changes after gastric bypass, with some groups growing more prominent and others diminishing in number
  • No one knew whether the altered microbial composition was merely a side effect of the surgery, or whether shifting bacterial populations could help people lose weight.
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  • To find out
  • fattened up mice then performed either bypass or a sham surgery on the animals
  • Mice in the bypass group lost about 29 percent of their body weight within three weeks of the procedure
  • even before the mice dropped weight, those in the bypass group already had an altered mix of intestinal bacteria
  • Compared with the sham operation group, the bypass mice had more of certain types of microbes
  • Some species of
  • are pathogens, but others help prevent inflammation and maintain intestinal health
  • Bypass mice also had more
  • bacteria, which can feed on mucus lining the intestines, particularly when the host is cutting calories
  • researchers speculate that the microbes somehow trigger fat-burning changes in the host’s metabolism
  • Then the researchers transplanted bacteria from the intestines of bypass mice into mice that had been raised without any bacteria
  • The formerly germ-free mice slimmed down, trimming about 5 percent of their body weight, even though they started out lean
  • Germ-free mice that received bacteria from the guts of sham surgery mice actually packed on a bit of fat
Mars Base

A new way to lose weight? Study shows that changes to gut microbiota may play role in w... - 0 views

  • by colonizing mice with the altered microbial community, the mice were able to maintain a lower body fat, and lose weight – about 20% as much as they would if they underwent surgery
  • New research
  • has found that the gut microbes of mice undergo drastic changes following gastric bypass surgery
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  • In some ways we were biasing the results against weight loss
  • the mice used in the study hadn't been given a high-fat, high-sugar diet to increase their weight beforehand
  • The question is whether we might have seen a stronger effect if they were on a different diet
  • finding ways to manipulate microbial populations to mimic those effects could become a valuable new tool to address obesity
  • study suggests that the specific effects of gastric bypass on the microbiota contribute to its ability to cause weight loss
  • need to learn a good deal more about the mechanisms by which a microbial population changed by gastric bypass exert its effects,
  • then we need to learn if we can produce these effects – either the microbial changes or the associated metabolic changes – without surgery
  • it may be years before they could be replicated in humans, and that such microbial changes shouldn't be viewed as a way to lose
  • pounds without going to the gym
  • the technique may one day offer hope to dangerously obese people who want to lose weight without going through the trauma of surgery.
  • may not be that we will have a magic pill that will work for everyone who's slightly overweight
  • But if we can, at a minimum, provide some alternative to gastric bypass surgery that produces similar effects, it would be a major advance
  • While there had been hints that the microbes in the gut might change after bypass surgery, the speed and extent of the change came as a surprise to the research team
  • In earlier experiments, researchers had shown that the guts of both lean and obese mice are populated by varying amounts of two types of bacteria
  • When mice undergo gastric bypass surgery, however, it "resets the whole picture
  • those changes occurred within a week of the surgery, and weren't short-lived – the altered gut microbial community remained stable for months afterward
  • the results may hold out the hope for weight loss without surgery
  • future studies are needed to understand exactly what is behind the weight loss seen in mice
  • A major gap in our knowledge is the underlying mechanism linking microbes to weight loss
  • certain microbes
  • found at higher abundance after surgery,
  • think those are good targets for beginning to understand what's taking place
  • the answer may not be the specific types of microbes, but a by-product they excrete.
  • In addition to changes in the microbes found in the gut, researchers found changes in the concentration of certain short-chain fatty acids
  • Other studies
  • have suggested that those molecules may be critical in signaling to the host to speed up metabolism, or not to store excess calories as fat.
  • hope to continue to explore those questions
  • such studies will allow us to understand how host/microbial interactions in general can influence the outcome of a given diet
Mars Base

Speed Of Light In Vacuum Is Not Actually Constant, Study Finds | Popular Science - 0 views

  •  
    Speed Of Light In Vacuum
Mars Base

Soyuz Makes Record-Breaking 'Fast Track' to Space Station - 0 views

  • The new abbreviated four-orbit rendezvous with the ISS uses a modified launch and docking profile for the Russian ships
  • It has been tried successfully with three Progress resupply vehicles, but this is the first time it has been used on a human flight.
  • In the past, Soyuz manned capsules and Progress supply ships were launched on trajectories that required about two days, or 34 orbits, to reach the ISS.
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  • The new fast-track trajectory has the rocket launching shortly after the ISS passes overhead
  • Then, additional firings of the vehicle’s thrusters early in its mission expedites the time required for a Russian vehicle to reach the Station
Mars Base

Space Station Crew Captures Soyuz Launch, As Seen from Orbit - 0 views

  • The Soyuz TMA-08M spacecraft launched at 2:43 a.m. Friday local time from the Baikonur Cosmodrome in Kazakhstan (4:43 p.m. EDT, 20:43 UTC on March 28),
  • crew of Pavel Vinogradov, Aleksandr Misurkin and Chris Cassidy
  • The fast-track launch had the crew arriving in just 5 hours and 45 minutes after launch
Mars Base

New US-Russian Crew Docks at Space Station After Super-Fast Flight | Space.com - 0 views

  • Before now, manned trips to the space station have taken at least two days, but with the docking of this ship just six hours after liftoff
Mars Base

True colors of some fossil feathers now in doubt (w/ Video) - 0 views

  • evidence for the colors of feathers—especially melanin-based colors—can be altered during fossilization
  • past reconstructions of the original colors of feathers in some fossil birds and dinosaurs may be flawed
  • In modern birds, black, brown, and some reddish-brown colors are produced by tiny granules of the pigment melanin
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  • These features—called melanosomes—are preserved in many fossil feathers, and their precise size and shape have been used to reconstruct the original colors of fossil feathers.
  • had no idea whether melanosomes could survive the fossilisation process intact
  • experiments show that this is not the case. Our results cast a cautionary light on studies of fossil feather color and suggest that some previous reconstructions of the original plumage colors of fossils may not be accurate
  • experimental technique pioneered in the group's recent study on the colors of fossil insects
  • simulated high pressures and temperatures that are found deep under the Earth's surface
  • team used feathers of different colors and from different species, but the geometry of the melanosomes in all feathers changed during the experiments
  • This study will lead to better interpretations of the original plumage colors of diverse feathered dinosaurs and fossil birds
Mars Base

Heart repair breakthroughs replace surgeon's knife - 0 views

  • Many problems that once required sawing through the breastbone and opening up the chest for open heart surgery now can be treated
  • through a tube
  • These minimal procedures used to be done just to unclog arteries and correct less common heart rhythm problems
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  • Now some patients are getting such repairs for valves, irregular heartbeats, holes in the heart and other defects—without major surgery
  • Doctors even are testing ways to treat high blood pressure with some of these new approaches
  • Instead of opening the chest, we're able to put catheters in through the leg, sometimes through the arm
  • Many patients after having this kind of procedure in a day or two can go home
  • It may lead to cheaper treatment, although the initial cost of the novel devices often offsets the savings from shorter hospital stays
  • Not everyone can have catheter treatment, and some promising devices have hit snags in testing
  • Others on the market now are so new that it will take several years to see if their results last as long as the benefits from surgery do.
  • these procedures have allowed many people too old or frail for an operation to get help for problems that otherwise would likely kill them
  • You can do these on 90-year-old patients
  • also offer an option for people who cannot tolerate long-term use of blood thinners or other drugs to manage their conditions
  • Heart valves
  • Millions of people have leaky heart valves. Each year, more than 100,000 people in the United States alone have surgery for them
  • Without a valve replacement operation, half of these patients die within two years, yet many are too weak to have one.
  • just over a year ago,
  • Edwards Lifesciences Corp. won approval to sell an artificial aortic valve flexible and small enough to fit into a catheter and be wedged inside the bad one
  • At first it was just for inoperable patients. Last fall, use was expanded to include people able to have surgery but at high risk of complications.
  • Catheter-based treatments for other valves also are in testing. One for the mitral valve
  • mixed review by federal Food and Drug Administration advisers this week; whether it will win FDA approval is unclear. It is already sold in Europe
  • Heart rhythm problems
  • Catheters can contain tools to vaporize or "ablate" bits of heart tissue that cause abnormal signals that control the heartbeat
  • Now catheter ablation is being used for the most common rhythm problem—atrial fibrillation, which plagues about 3 million Americans and 15 million people worldwide.
  • Ablation addresses the underlying rhythm problem. To address the stroke risk from pooled blood, several novel devices aim to plug or seal off the pouch
  • The upper chambers of the heart quiver or beat too fast or too slow. That lets blood pool in a small pouch off one of these chambers
  • Clots can form in the pouch and travel to the brain, causing a stroke
  • a tiny lasso to cinch the pouch shut. It uses two catheters that act like chopsticks. One goes through a blood vessel and into the pouch to help guide placement of the device, which is contained in a second catheter poked under the ribs to the outside of the heart. A loop is released to circle the top of the pouch where it meets the heart, sealing off the pouch.
  • A different kind of device
  • sold in Europe and parts of Asia, but is pending before the FDA in the U.S
  • like a tiny umbrella pushed through a vein and then opened inside the heart to plug the troublesome pouch.
  • Early results from a pivotal study released by the company suggested it would miss a key goal, making its future in the U.S. uncertain.
  • Heart defects
  • St. Jude Medical Inc.'s Amplatzer is a fabric-mesh patch threaded through catheters to plug the hole
  • In two new studies, the device did not meet the main goal of lowering the risk of repeat strokes in people who had already suffered one, but some doctors were encouraged by other results
  • Сlogged arteries
  • The original catheter-based treatment—balloon angioplasty—is still used hundreds of thousands of times each year in the U.S. alone
  • A Japanese company, Terumo Corp., is one of the leaders of a new way to do it that is easier on patients—through a catheter in the arm rather than the groin
  • Newer stents that prop arteries open and then dissolve over time, aimed at reducing the risk of blood clots, also are in late-stage testing
  • High blood pressure
  • About
  • 1 billion people worldwide have high blood pressure, a major risk factor for heart attacks
  • Researchers are testing a possible long-term fix for dangerously high pressure that can't be controlled with multiple medications.
  • uses a catheter and radio waves to zap nerves, located near the kidneys, which fuel high blood pressure
  • At least one device is approved in Europe and several companies are testing devices in the United States
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