9 Flashcards
What are the low and high risk strains of human papillomavirus (HPV) virus?gra
6 and 11 - low risk - cause anogenital warts and CIN
16 and 18 - high risk - cause cervical cancer
Types of necrosis and an example for each
Coagulative - can see structure but lose nuclei e.g. ischaemic kidney
Caseating - granulomatous inflammatory response e.g. TB granuloma
Liquefactive - influx of inflammatory cells producing pus e.g. gangrene or cerebral infarct
Physiological functions of skin?
- Vitamin D synthesis
- Temperature regulation
- Immune defence
- Protection against UV radiation
- Sensation and nerve signalling
What are the layers of the epidermis?
- Stratum corneum
- (Stratum lucidum) - only found in thick skin llike palms
- Stratum granulosum
- Stratum spinosum
- Stratum basale
Which cells would you find in the stratum basale?
- Keratinocytes - synthesise keratin
- Melanocytes - synthesise melanin
- Merkel cells - touch sensitive cells
Which cell would you find in the stratum spinosum?
Langerhan cells
These are found in other epithelial layers but highest concentration found here
Which cell would you find in the stratum granulosum?
Keratinocytes continuing their journey
Which cell would you find in the stratum corneum?
Corneocytes
Which 2 parts make up the dermis?
Thin papillary layer and thick reticular layer
Necrosis associated with bacterial infections?
Liquefactive (aka Colliquativ )
What causes gout?
Xanthine oxidase overactivity
Where is most likely to suffer haemorrhagic necrosis?
- Testis - testicular torsion
- Spleen
- Lung
Where are you most likely to find fat necrosis?
Pancreas - pancreatitis
An example of gummatous necrosis?
Syphilis
List cytoplasmic changes in necrosis.
- Increased eosinophilia
- Swelling
What are nuclear changes in necrosis?
Pyknosis - dark clumps
- irreversible condensation of chromatin in the nucleus of a cell undergoing necrosis or apoptosis
Karyolysis - dissolution of cell nucleus
Karyorrhexis - fragmentation of nucleus whereby its chromatin is. irregularly distributed throughout the cytoplasm
What is a facultative anaerobe and give an example?
Without oxygen can switch to fermentation and will grow - E. Coli, Staphylococcus Aureus
What is an obligate anaerobe?
Die in the presence of oxygen - Klebsiella Pneumoniae
Describe the structure of a gram negative bacteria.
- Thin peptidoglycan layer
- LPS outer membrane
What can prokaryotes be divided into?
Bacteria and archaea
Describe the structure of gram positive bacteria.
Thick peptidoglycan layer
No outer membrane
Teichoic acid - PAMP
Biochemical markers of cell death.
ALT - liver enzyme
Troponin - cardiac myocytes
Creatinine kinase - muscle
Which gram bacteria can sometimes cause spores and give an example?
Gr+
Clostridium Difficile + Clostridium Botulinum
Give the features of bacterial cells.
- Cell wall
- No nucleus
- No mitochondria
- Circular chromosome
- Pili
- Flagellum
- No organelles
- Transcription and translation occur at the same time