英語聽力文摘 細(xì)菌里的防護(hù)欄
Fencing in Bacteria
綠膿桿菌(p.aeruginosa)或稱銅綠色假單胞菌，是一種致病力較低但抗藥性強(qiáng)的桿菌。廣泛存在于自然界，是傷口感染較常見的一種細(xì)菌。能引起化膿性病變。感染后因膿汁和滲出液等病料呈綠色，故名。綠膿桿菌(p.aeruginosa)屬假單胞菌屬(pseudomonas)，廣泛分布于自然界及正常人皮膚、腸道和呼吸道，是臨床上較常見的條件致病菌之一。
What do you do when infected with Pseudomonas aeruginosa? You'll want to know! Find out on this Moment of Science.
You know how they say good fences make good neighbors? Well, this adage might have some applications in medicine. Imagine that you go in for major surgery, and get a post-op infection with Pseudomonas aeruginosa. What do you do?
Pseudomonas is especially virulent in that it slides right by your immune system, and is resistant to antibiotics. But the thing is that Pseudomonas bacteria live contentedly in the bowels of about three percent of all people, which adds up to almost nine million Americans.
But when your body undergoes major stress, like surgery, the Pseudomonas bacteria may respond to the changes in your body’s chemistry, and to the erosion of the mucus that coats the intestines that occurs whenever you’re hooked up to an IV and nutrients bypass the digestive system. When that happens, Pseudomonas go on the attack, boring through the intestines’ lining and into the bloodstream. It’s best to avoid agitating the bacteria in the first place.
Well,in one study, scientists were able to prevent post-op infection in mice by coating their intestines with a high-molecular-weight polymer. This worked as a bio shield to prevent the chemical signs of stress from reaching the bacteria, while also acting as a barrier, like mucus. Mice that normally would have died managed to survive with no noticeable side effects.
It’s a promising study, and scientists hope to refine it so that one day we’ll be able to fight off infections by preventing them in the first place.
