When the enemy invades our bodies, rapidly overwhelming our defences, bringing pain and misery... when there is no defence... no hope... only death;  only one thing can make a difference - 'antibiotics'... Nature's little helpers: 
  Another extraordinary Micscape Magazine article by Maurice Smith and Andrew Syred (c) Micscape Magazine 1997


Two weeks ago, a slight occasional 'itching' pain in my upper jaw progressed rapidly to a nightmare state of screaming agony. The culprit: a tooth abscess!

I'll quickly say that the pain has gone. A nerve extraction along with treatment to clear the abscess has done the job. But the experience made me think about the method used to get rid of the abscess itself. Just what am I absorbing into my system when I hastily gulp down those antibiotic capsules, so readily given (and accepted) when infection strikes quicker than our internal immune systems can fight back?

Yes, I know we should take every last capsule in the prescribed bottle. To do less, paves a way for the infecting bacteria to develop immunity to the antibiotic itself. Since I had received additional injections of antibiotics as part of my emergency treatment, I thought I would hold back one capsule to take a closer look.

The bottle it came in says the antibiotic is: Amoxycillian 500 Mg. (Milligram)

You just can't own a microscope and not take a closer look, so I gently prised apart the two halves of the outer casing to see what was inside.There was not a lot to see - just a great quantity of whitish powder that spilled out as though it was already fed up with being constrained in too smaller a space.

As the white 'innocent-looking' material fell like dust to the floor of my room, no matter how steadily I held the tiny container it was packed into, I started to get the feeling that this stuff was eager to escape its tiny prison! It just  wanted to get out and get going!

Funny thing: a few days ago I was shunting these things down my throat like they were the last cure on earth, and now here I was starting to get worried about breathing the stuff in; no doubt, a healthy attitude when dealing with the unknown - I reassured myself. None of my books really explained anything in detail about this antibiotic stuff. Sure - it helps to knock out bacteria, we all know that... and yes... I realize it must be pretty potent stuff to save so many lives since it has been used - but what the heck does it really look like?

I emptied out a small quantity of the white dust onto a slide, put a cover slip on top, and slipped it under the microscope. This piccie shows a very small amount of the  Amoxycillian sprinkled onto the surface of a specimen slide.
I have to confess, at this point, I may have well just have been shaking out the talc bottle from the bathroom, because looking at the white stuff on the slide without a microscope, wasn't telling me much!

You don't get to see much more when looking at it under the microscope. At 400x magnification, this is all you see. Keep in mind that the streaks have been caused by the movement of a cover slip, laying on top of the fine powder. The small specks represent individual elements of the antibiotic. The patchy marble-looking colour across the image is actually nothing at all, just the effect of sticking a video camera (with a coated lens) on top of the microscope lens system. I suspected I was looking at something here that was 'frozen' into an inert state. What was required to bring some 'life' and movement into this specimen slide, is the addition of water. I removed the cover slip, added a few drops of deionised water, and put it back under the scope.

In less than a minute,  the slide was alive with activity. I could see what appeared to be tiny green rods, surrounded by jelly like material, twitching and moving through the water. Here is a low quality streaming video of the activity. You can't see the 'rods' in this due to the poor quality of the video, but keep an eye on the tiny black dots and get a 'feel' for the overall movement and activity here.

It's one thing seeing these little 'helpers' but quite another understanding how they actually help to fight infection. A visit to various web pages, books, and other resources reveals all. I thought a very easy-to-follow, non-technical, explanation would do far more good here than a detailed one full of scientific names and terms; so here we go then:-

Antibiotics either kill bacteria directly or inhibit their ability to increase their numbers. The term 'antibiotic' is used in a general sense, embracing a wide range of natural organic compounds as well as synthetic and semi-synthetic ones. Naturally occurring compounds like penicillin originate from molds or other bacteria. Antibiotics are toxic to bacteria but harmless to human cells - although a small minority of people can be harmed by specific antibiotics due to being allergic to them!

Although the original antibiotic, Penicillin, was discovered in 1928, it wasn't until the 1950's that antibiotic use became widespread. It's quite difficult to appreciate how they work. The simplest way is to see that some molds and bacteria give off chemicals into their immediate environment deliberately in order to preserve it for their own growth and reproduction. This action prevents competition from other living organisms - other bacteria - from thriving in the local vicinity. The compounds used in this 'warfare' either break down the cell walls of 'enemy' bacteria - causing their internal processes to leak out - or they interfere with the formation of the cell walls in the rival bacteria. The first mechanism explicitly kills bacteria, whereas the second one inhibits growth and reproduction of the infecting cells, enabling our body's natural defences to build up and overwhelm the invader.
 

The interesting point about the antibiotic we have looked at here (Amoxycillian) is that to a rank amateur like me, it is easy to misinterpret the movement seen under the microscope. For example, I thought the 'twitching' green rods were themselves living organisms, somehow freeze-dried and  re-engineered by microbiologists to emit the 'killer' compound into our systems. I soon found out how wrong I was!
 

It's easy to make such a mistake when observing very tiny particles in water or another fluid. Here, let me show you a graphic example of what one of the rods looked like to me: obviously - enlarged and simplified for the sake of clarity here. See it 'twitching?'

My good friend Andrew Syred soon put me right: "What you are seeing Mol", he said, "is Brownian Motion. The rod things are not living organisms, just simply very tiny particles of the organic compound slowly dissolving  in the water. The motion is caused by the random movement of water molecules bumping into the solid particles, jiggling them around. If you watch closely, you will see none of the rods have a common or definitive direction of travel."

So, watch I did - and he was right! I had heard of Brownian motion but not really thought about it much; after all, most of the things I have studied to-date have been living organisms like pond life.

So if you want to see Brownian motion first hand, empty out your last antibiotic capsule into some water, and take a look under the scope. But be quick because...

...the use of antibiotics as a way of combating infectious diseases may be very short lived: bacteria have developed responses to the antibiotics, enabling many species to become immune to their action. In the main, this is our own fault. It is vital to complete the entire course of prescribed antibiotics to ensure surviving bacteria do not pass on 'resistant' characteristics.
 
 

Editor's note: a special Microscopy Around the Home article to complement Maurice's article describes common materials you can use to study Brownian motion.

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ALL MATERIAL (C) MICSCAPE MAGAZINE 1997  

Explanation of Brownian motion
Brownian motion (alternatively known as pedesis) is described as the erratic random motion of microscopical particles in suspension, can be in air or liquid. Caused by the continuous irregular bombardment of the particles by molecules of the surrounding medium. Named after Robert Brown (1773-1858) who described the phenomenon in an 1827 paper although he was not the first to describe the phenomenon.
     This article is dedicated to:-
The unknown dentist at Denmark Hill Dental Hospital Emergency Centre, London, who kindly, and very gently, took away my misery when all else had failed...  ...and to all people who's lives are spent combating the ills and troubles which intrude into our lives. Often, their endeavours receive little reward except for the knowledge that they have eased our suffering.

 


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