Flu – Virus in a Wooden Horse

Posted by on Mar 22, 2014 | 0 comments

We’ve talked about one major class of infectious agents: bacteria. Let’s look at the other major class: viruses.

What is a virus?
A virus is a piece of genetic material wrapped in a protein coat: essentially an instruction sheet inside a box. We’re not really sure if viruses are alive. They reproduce and evolve like life, but they don’t have cells, metabolism, and don’t react to being poked, as all other lifeforms do. They also can’t reproduce without the help of a living cell. Have a handful of scientists debate this idea at your next dinner party – it’ll be fun.

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UTI – Bacteria Invasion

Posted by on Sep 15, 2013 | 0 comments

I’ve somehow made it through 5 stories without talking about one of the most famous pathological agents… bacteria.  It’s time.

Bacteria1 are incredibly different from us.  We are more closely related to dinosaurs, roses, mushrooms, and even slime molds than we are to bacteria!

A greatly pruned version of the tree of life - bacteria branch off from most other forms of life very early.

A greatly pruned version of the tree of life. Bacteria branch off from most other forms of life very early.

There are plenty of good bacteria – they make yogurt or break down our trash– but the most famous are the bad ones.  They have names like E. coli, Staph, and Strep, and we don’t particularly enjoy their presence.  Generally, when bacteria invade, the invaded part gets warm, swollen, and tender (though there are many exceptions).  Let’s learn more by looking at one particular kind of invasion: a urinary tract infection (UTI).

  1. Bacteria is plural, bacterium is singular (because it’s a Latin neuter noun).  Now you can sound like a nerd. []
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Fracture – Rebuilding Bone

Posted by on Aug 18, 2013 | 1 comment

In honor of my dear mother, today we’re looking at repair of a broken bone.  Get well soon, Mama!  Hang in there, Daddy!

Disclaimer: I’m not a doctor – just a bioengineer who happens to find pathophysiology fascinating.  If you find an error, please let me know!  Also, NONE of my drawings are to scale.

Today we turn to a common ailment: broken bones.  Because, as I learned, reading about how bones get fractured freaks me out1, we’ll jump in right after Jill has broken her arm.  Sorry we weren’t there to stop it, Jill.

 

Sorry, Jill.

Sorry, Jill.

Jill's broken elbow.

Jill’s broken elbow.

 

Steps to repairing this bone:

  1. as does any trauma to the eye.  I’m too empathetic!  If you want to see a post about injured eyes on Pathology Storybook, you’ll need to write it yourself. []
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Hives – A Body on High Alert

Posted by on Feb 16, 2013 | 3 comments

Today, we’ll be following an anaphylactic reaction to an allergen.  

Disclaimer: I’m not a doctor – just a bioengineer who happens to find pathophysiology fascinating.  If you find an error, please let me know!  Als0, NONE of my drawings are to scale.

An allergy starts out very innocently.  Everything is humming along: white blood cells patrolling the blood stream, stomach merrily digesting shellfish, or medicine destroying bacteria.

Meet Jill.

Hello!

Hello!

Jill’s taking a particular antibiotic for the first time, and it’s working great: fighting bacteria just like it’s supposed to.

Unfortunately, her white blood cells are getting curious. 

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