Intersystems Flashcards
what family is HIV? what typeof nucleic acid?what receptor does it bind to on entry? where is replication? where is assembly?
retrovirdae, ss RNA. binds to CD4 receptor on entry, replicates in nucleus, assembles in cytoplasm.
2 HIV proteins he didnt shut up about? what are they involved in
TAT and REV. TAT involved in transcription. REV - Regulates Expression of Virion proteins
name 3 ways HIV avoids immune response
high mutation rate, latency, altered antigen presentation
4 targets for anti HIV drugs
fusion/entry inhibitors, reverse transcriptase inhibitors, integrase inhibitors, protease inhibitors
where do most lesions arise from in breast path?
epithelium of the terminal duct lobular unit
dif b/w fibrocystic change and fibroadenoma in breast path?
cyst = benign. multifocal and bilateral. fibrosis with cyst formation. Adenoma = benign - usually in younger women. solitary well circumscribed mass. presents as lump
define a carcinoma in situ. name the 2 types.
what are the 2 invasive carcinomas? which is more common
Malignant population of cells confined to ducts and/or acini, w/o invasion through basement membrane.
Ductal Carcinoma in Situ.
Lobular Carcinoma in Situ.
same as non-invasive. Ductal and lobular. Ductal much more common (D for Death).
where are most of the accessory cells within the epidermis?
stratum basale
skin circulation?
2 main plexuses.
Papillary plexus - Beneath papillary dermis.
Cutaneous plexus- At junction of dermis and hypodermis.
where is the thickest skin
on back
what type of cell is a merkel cell? role
neuroendocrine, somatosensory
pain fibres of the peripheral nerve and their difs?
A delta = fast. C = slow
3 organisms that transmit via airborne
TB, measles, Varicella
type of virus is ebola? countries affected? how long til symptoms appear after infection? when and how can transmission occur?
Filovirus, Guniea, Sierra Leone and Liberia. 2-21 days. transmission only during clinical illness via body fluids
definition of fever? when is temperature higher? optimum temp for immune response?
oral above 37.8 or morning above 37.2. Higher in afternoon. Optimum temp for immune is 39.5
4 differentials for PUO
infection, connective tissue disorder, malignancies, other (drugs)
in which disease can Pseudomonas Aurigenosa be potentially more virulent
Cystic Fibrosis
which common superficial places can Pseudomonas Aurigenosa infect (2)?
skin: wound infection or ottitus externaeye: keratitis(cornea)
how do biofilms aid bacterial survival?
resist mechanical removal and are less visible to the innate immune system
most common cause of fungal meningitis?
cryptococcosis
what do dermatophytes cause?
tinea
where is candida albicans carried in the body (2)
gut and vagina
which virus is associated with lymphomas
EBV
name 3 risk factors for lymphomas
immunosuppresion, some autoimmune diseases (hashimotos) and EBV
4 eye problems affecting indigenous people
trachoma. cataracts, diabetes, refractive error
explain what does trachoma cause? how can it be prevented
repeated infections causes blindness. can be treated with good facial hygiene.
3 ways venom causes death. explain each
- haemotoxicity - can contain a v powerful pro coagulant → localized clotting → strips the body of clotting factors (fibrin) → vulnerable to catastrophic bleed.
Can also can also be a very powerful anti-coagulant → vulnerable to catastrophic bleed. - neurotoxicity - paralysis
- Myotoxicity - Rhabdomyolosis causing renal failure. (muscle breakdown > increase myoglobin > damage kidney)
3 types of haemoglobinopathies - give an example
- decreased/no synthesis of globin chains (a or b thalassemia).
- Structural variation to Hb (sickle cell anaemia).
- persistent fetal haemoglobin HbF (not clinical).
genetic mutation for each of alpha, beta and sickle cell?
alpha = large deletion.
other 2 are point mutations
symptoms of beta thalasseima? (4)
failure to thrive, anaemic, thinning of long bones & cranial bones(to make more blood cells) ,facial maxillary overgrowth
Hepatosplenomegaly
name 3 mechanisms for gene mutation
chromosomal translocation, point mutation and viral/bacterial
Philadelphia chromosome is involved in which leukaemia? 2 chromosomes and genes involved
CML. 22;9 Bcr-Abl
Gleevec (imatinib) is a treatment for which leukaemia? what is its MOA
CML. A specific Bcr-Abl tyrosine-kinase inhibitor
BH-3 only mimetic ABT-199 is a drug in clinical trial for which disease?
CLL
Main gene involved in CLL? what happens
Bcl-2 - over-expression prevents apoptosis
miRNA(15,16), ZAP -70 and p53 involved with which cancer?
CLL
Describe, using examples, how SNPs can change Pharmacokinetic and Pharmacodynamic behavior of drugs.
Kinetics - with statins - a SNP in one of the liver transport genes will decrease statin uptake and increase toxicity.
Dynamics - SNP in the 5-lipoxygenase gene is predicitve of poor response to anti-luekotriene therapy in asthma
describe why an opioid receptor agonist and antagonist may be combined
one for pain relief and one to prevent constipation
what happens in folliculitis and what is most common cause?
blockage of hair follicle caused by Staph A
S. aureus produces a vast array of virulence factors to enable it to overcome immunity. name 5
- Binds to damaged tissues via adhesins
- inhibits chemotaxis
- Inhibits phagocytosis
- If ingested by PMNs, can resist killing
- forms biofilms
key feature that differentiates CA-MRSA from HA-MRSA
CA-MRSA has the gene for PV-leukocidin
M protein is a virulence determinant associated with which organism
GAS
what is a NET? which bacteria can overcome this and how
Neutrophil Extracellular Trap - the neutrophil essentially forms a net of DNA arround the organism.
GAS can overcome this with a DNAse
what kind of trauma is pseudomonas infection likely to result (2)
diabetic foot ulcer and burn
how much blood is made? how often
red cell 3-5 x 10^12 p/L. 120 days
White 2-6 x 10^9 p/L. 3-5 days
Platelets 150-400 X 10^9 p/L. 10 days
sites of Haemopoiesis throughout life
Yolk Sac - first few weeks.
Liver and spleen - 6weeks-7 months.
Bone marrow - 7 months- throughout life
name 3 haemantics
iron, B12, folate
non anaemic sign of iron defficiency
pica
components of a RBC (3)
membrane, haemoglobin, enzymes
single most important physiological equation related to blood?
Measurements
Tissue oxygen delivery = CO x Hb x %sat x 1.34.
l/min x g/l x % x mls/g = mls/min
anaemia is defined…
Hb levels below that which is normal for age and gender
2 main reasons for microcytic anaemia, one for child and one for adult
iron defficiency (diet) and blood loss (colon cancer)
lack of B12 or folate can cause macrocytic anaemia, why?
they needed for DNA replication. cells grow big coz cannot produce DNA quickly enough to divide at the right time
