Leeuwenhoek had stolen and peeped into the fantastic sub-visible world of little things, creatures that had lived, had bred, had battled, had died, completely hidden from and unknown to all men from the beginning of time. Beasts these were of a kind that ravaged and annihilated whole races of men ten million times larger than they were themselves. Beings these were, more terrible than fire-spitting dragons or hydra-headed monsters. They were silent assassins that murdered babies in warm cradles and kings in sheltered places. It was this invisible, insignificant, but implacable-and sometimes friendly- world Leeuwenhoek had looked into for the first time of all men of all countries. ~Microbe Hunters

Monday, 29 April 2013

(Xylene and) Yersinia

I forgot to do an X for Saturday! X is for xylene which is a chemical used in histology for removing wax from embedded and cut tissue samples in the processing stage and before and after staining. 

The absolute only thing that starts with a Y in the lab that I could think of is Yersina. Yersinia pestis is the bacterial infection that is responsible for the plague. As opposed to the Middle Ages, in present day, we do not see many infections of Yersinia because of our fairly conscious health, hygiene and anti-rodent controlled conditions and our world-wide recognition systems to prevent such outbreaks. In the past, the rodent-bourne infection caused many devastating outbreaks, like the Bubonic Plague aka the black plague, and has since been manufactured into an antibiotic resistant potential bioweapon.

Diagnosis and treatment of Yersinia pestis, and other members of the Enterobacteriaceae family, are easily done by automatic testing machines, or manually by a series of inoculated tubes, with the resulting pattern of results of the tubes indicating the identity of an organism. The tubes contain ingredients such as carbohydrates, to find out what the organism metabolizes for energy and growth, and their corresponding indicators, or tubes for visualizing motility of the organism. After the known species of the organism is known, then antibiotic susceptibility testing can be done to determine the best course of action to treat the infection. Yersinia are not naturally a very resistant genus of bacteria, so treatment can be carried out easily.

If you try and save a cat choking on a rat and get bit by an accident, you may get Yersinia. I suggest you don your old scratchy linen tunic and walk to your closest medicine man for some herbal leaves. Because really, this illness that medieval (or you are in a part of the world where that is the only way of life). 

Darn good and sure of it,



  1. Oh wow!! How interesting this was! Lucky my cat is indoors! Thank you for sharing such interesting information!!

  2. I'm glad there are people who are interested in this stuff (otherwise how would these things be cured and prevented?). You did a wonderful job of making it easy to understand. :-)