EOS 2

Remember Marcus' text message to me :

(sorry for destroying your post vanessa (= )

i thought i'd give my two singaporean cents worth (i.e approximately 5sen)

in addition to your 2sen

these are for OSPE (Microbio):

***when you are given a picture of an organism (bacteria)***

a) identify (or read - they should state it) the stain

b) (if it is gram stain) state whether it is

1) gram Positive (darkish purple) OR
2) gram Negative (reddish pinkish)

c) describe the shape of the organism:

1) Cocci (spherical) OR
2) Bacilli (rodshaped) / OR
3) spiral?

- if its two cocci kissing each other - DIPLOcocci

d) dont need to state the name of the organism unless they ask (they will most probably ask in a subsequent question - after they give more clues/features)

e) try to correlate the characteristics to the possible organism in picture - have an idea in your mind


- i'll just list down what i can remember (without pictures) - try to find the pictures to match the descriptions if you can. you can and MUST score for microbio OSPE (= because the things that can come out are very limited. i'll do my best to cover the majority of it.

1) Corynebacterium diphtheriae,
Chinese letter, Gram -ve,

Dark gray colonies on Blood tellurite agar.

Albert Stain for metachromatic granules.

gray faucial membrane

2) Mycobacterium Tuberculosis

- causes Tuberculosis (TB)

- (Mycobacterium Bovis causes TB as well)

- (Mycobacterium Leprae causes Leprosy)

- CULTURE : - Lowenstein-Jensen medium

- STAIN: - Ziehl-Neelson stain (acid-fast) -stains RED

- does not stain well with gram stain

- Rx for tuberculosis: 4 drugs

Rifampicin
Isoniazid
Pyrazinamide
Ethambutol

3) Treponema Pallidium

- causes SYPHILIS (chancres - genitals (think STD - SEXSEXSEX)

- does not stain well with Gram stain cuz its a SPIROCHETE
(other spirochetes: Borrelia, Leptospira)

- visualized using Darkground Microscopy / Immunoflorescence / Silverstain


4) Know the difference between Staphylococcus and Streptococcus.

- StAphylococcus contains cAtAlAse / Streptococcus doesnt.

- CATALASE test (to differentiate staph from strep) :

i) wire loop is rubbed across a colony of gram +ve cocci
ii) and mixed on a slide of H202 (hydrogen peroxide)
iii) if bubbles appear:- catalase is present. the organism is STAPH. vice versa.
-- (2 h202 ----> 2h20 + 02) - the bubbles due to Oxygen being liberated

a) Streptococcus Pneumoniae (aka Pneumococcus) :

- Gram +ve, DIPLOcocci ,

- Major virulence factor: Polysaccharide Capsule.

- Causes: (i) meningitis(in adults) (ii) otitis media(in kids)


b) Staphylococcus Aureus ( Aureus means GOLD )

- Golden Colonies on Blood Agar

c) Know the difference between alpha / beta haemolytic streptococcus

- alpha-haemolytic: partially lyse RBC - greenish discolouration of the culture medium

- beta-haemolytic: COMPLETELY lyse RBC - clear zone of haemolysis around the colony.



5) Know that MacConkey's agar

- is used to differentiate Lactose Fermenters from Non-Fermenters.

- Know the colour of the colonies of the fermenters and non-fermenters.



6) Know how to interpret the Antibiotic Sensitivity Test (culture)

- the greater the clear area surrounding the antibiotic, the more POTENT /EFFECTIVE the antibiotic is

- the smaller the clear area surrounding the antibiotic, the more RESISTANT the organism is towards the antibiotic.

- used to determine the choice of antibiotic for Rx



7) gram NEGATIve cocci;

Marcus --- Moraxella
Nicholas--- Neisseria -- +PUS CELLS (w00t pus) --- gram -ve DIPLOcocci
Vanessa--- Veillonella ----NOT thattt IMPORTANT rawr.


8) the GRAM POSITIVE ORGASMS

COCCI (spherical)

a) STReptococcus ( STRips of cocci)
b) Staphylococcus (clusters of cocci - think GRAPES)

BACILLI (spore formers)

a) Bacillus (aerobic)
b) Clostridium (anaerobic)
-Clostridium Tetani - TERMINAL spores (look like drumsticks)

* i recall using this way - bacillus has a shorter spelling than clostridium
aerobic has a shorter spelling than anaerobic

henceforth (brilliantly):
bacillus - aerobic spore former and consequently,
clostridium - anaerobic spore former.

BACILLI (non-spore formers)

a) Corynebacterium (refer above)
b) Listeria

KICK BUTT KICK BUTT KICK BUTT KICK BUTT KICK

BRAIN ABSCESSSSSSSSSSSSSSSSS?
:)

Jesus looked at them and said, “With man this is impossible, but not with God; all things are possible with God.”" Mark 10:27

For good recollection of your memory.
For guidance as you write your answer.
For good observation of the slides.
For clarity of everything studied.

In your 11th hour.
In your final preparations.

Godspeed & God Bless

(Sorry if my use of religion offends you)
Have faith
[because I have faith in you too]
:)

All the best M2/07 !

The atropine for your sinus bradycardia,
Vanessa x


KICK ASS.