Basic sciences Flashcards
what is the mode of function of mycophenolate mofetil?
inhibits of inosine-5’-monophosphate dehydrogenase which is needed for purine synthesis
Mycophenolate mofetil (MMF) reduces lymphocyte production
what is the protein mutation in marfan’s syndrome?
fibrillin -1
FBN1 gene on chromosome 15
what is the mechanism of action of denosumab?
human monoclonal antibody that inhibits RANK ligand, which in turn inhibits the maturation of osteoclasts
how does strontium ranelate function?
dual action bone agent’ - increases deposition of new bone by osteoblasts (promotes differentiation of pre-osteoblast to osteoblast) and reduces the resorption of bone by inhibiting osteoclasts
what are the main side effects of strontium renelate?
increased risk of cardiovascular events
increased risk of thromboembolic events
what are the different HLAs assocaiated with diseases?
HLA-DR1: bronchiectasis
HLA-DR2: systemic lupus erythematous (SLE)
HLA-DR3: autoimmune hepatitis, primary Sjogren syndrome, type 1 diabetes Mellitus, SLE
HLA-DR4: rheumatoid arthritis, type 1 diabetes Mellitus
HLA-B27: ankylosing spondylitis, postgonococcal arthritis, acute anterior uveitis
Which cell surface protein does HIV use to enter cells?
CD4
what is the function of atrial natriuretic peptide?
- promotes excretion of sodium
- lowers BP
- antagonises actions of angiotensin II, aldosterone
what are the conditions associated with HLA DR2?
narcolepsy
Goodpasture’s
what are the conditions associated with HLA DR3?
- dermatitis herpetiformis
- Sjogren’s syndrome
- primary biliary cirrhosis
what are the conditions associated with HLA DR4?
T1 diabetes mellitus
Rheumatoid arthritis
what are the conditions associated with HLA A3?
haemochromatosis
what are the conditions associated with HLA B51?
behchet’s disease
how does ciclosporin work?
Ciclosporin is an immunosuppressant which decreases clonal proliferation of T cells by reducing IL-2 release. It acts by binding to cyclophilin forming a complex which inhibits calcineurin, a phosphatase that activates various transcription factors in T cells
what are the species that can cause cutaenous leishmaniasis?
Leishmania tropica or Leishmania mexicana
it is typically diagnosed by doing a punch biopsy from the edge of the lesion allowing for both histology and culture
cutaneous leishmaniasis acquired in South or Central America merits treatment due to the risk of mucocutaneous leishmaniasis whereas disease acquired in Africa or India can be managed more conservatively
what is the cause of muco-cutaenous leishmaniasis?
- caused by Leishmania braziliensis
- skin lesions may spread to involve mucosae of nose, pharynx etc
what are the features of visceral lieshmaniasis?
Leishmania donovani
fever, sweats, rigors
massive splenomegaly. hepatomegaly
poor appetite*, weight loss
occasionally patients may report increased appetite with paradoxical weight loss
grey skin - ‘kala-azar’ means black sickness
pancytopaenia secondary to hypersplenism
how does PDE5 inhibitor work?
PDE5 inhibitors cause vasodilation through an increase in cGMP leading to smooth muscle relaxation in blood vessels supplying the corpus cavernosum.
what are the JVp waves?
a- atria contract
c- tricuspid closes
x- atria rela’x’es causing drop in pressures
v- atrial filling
y- tricuspid opens
what is a type II sentivity reaction?
IGg or IGm bind to the antigen on cell surface
- autoimmune haemolytic anaemia
- ITP
- goodpasture’s syndrome
- pernicious anaemia
which foramina do the different divisions of the trigeminal nerve pass through?
SRO
OPHTHALMIC NERVE (V1) — Superior orbital fissure
MAXILLARY NERVE (V2) — Rotundum
MANDIBULAR NERVE(V3) — Ovale
what are the retroperitoneal organs?
Retroperitoneal Organs: SADPUCKER
S: supearenal (adrenal) gland
A: aorta
D: duodenum
P: pancreas
U: ureter
C: colon
K: kidneys
E: Esophagus
R: rectum
what is the percentage covered within the SD distributions?
68.3% of values lie within 1 SD of the mean
95.4% of values lie within 2 SD of the mean
99.7% of values lie within 3 SD of the mean
what is seen on urinary casts for acute tubular necorsis?
granular casts
epithelial casts
what are the conditions associated with red blood cell casts?
glomerulonephritis
renal ischaemia and infarction
what is the formula for relative risk reduction?
Relative risk reduction = (EER - CER) / CER
EER - Experimental event rate
CER - Control event rate,
how do you calculate NNT in relation to absolute risk reduction?
1/ absolute risk reduction
what molecular biology blotting techniques can be used to separate molecules?>
SNOW (South - NOrth - West)
DROP (DNA - RNA - Protein)
what are the features of tay-sachs disease?
accumulation of GM2 ganglioside within lysosomes
Hexosaminidase A defect
- developmental delay
- cherry red spot on the macula
- liver and spleen normal
what does vitamin b2 (riboflavin) deficiency cause?
- angular chelitis
what compliment deficiencies can cause symptooms
c5-9
prone to neissiria meNINEGITIS
C3
C and 3 have recurrent sounds
- recurrent infections
C1 inhibitor (C1-INH) protein deficiency
causes hereditary angioedema
what are the features of fabry disease?
X-linked recessive
deficiency of alpha-galactosidase A
FABRYS:
Fever
Angiokeratomas / Alpha-galactosidase A
Burning pain
Renal
YX (x linked recessive)
Stroke / Cardiovascular
what are the features of gaucher’s disease?
Most common lipid storage disorder resulting in accumulation of glucocerebrosidase in the brain, liver and spleen.
Key features include hepatosplenomegaly, aseptic necrosis of the femur
what is the mode of inheritance of friedriech’s ataxia?
autosomal recessive
what cells are involved in the hyperacute organ rejection?
B cells
how do proteasomes identify compounds to break down?
degradation of protein molecules that have been tagged with ubiquitin
what is li fraumeni syndrome?
Li-Fraumeni is an autosomal dominant disorder characterised by multiple cancers such as leukaemias, sarcomas, brain, breast and adrenal malignancies.
what ae the different types of immune reactions?
1 - allergic, anaphylaxis
2. antibody
3. complex
4. - delayed
4- graves and gravis
ABCDG
what does C5 deficiency cause?
leiner disease
- erythroderma desquamativum, is a severe form of seborrheic dermatitis that typically begins in infancy
- recurrent infections and diarrhoea
what is the position of the eye in marfans and homocystinuria?
moon is up and home is down
marfans eye is up and
homocystinuria - eye is down
which chromosome are the HLA antigens encoded on?
chromosome 6
what mode of inheritance is G6PD?
x-linked recessive
what are the different blotting techniques and what do they detect?
SNOW (South - NOrth - West)
DROP (DNA - RNA - Protein)
what are the histological findings of diabetic nephropathy?
Kimmelstiel-Wilson lesions, nodular glomerulosclerosis, hyaline arterioscleoris
what cell surface protein can be detected in hodgkin’s lymphoma?
CD15 - reed sternberg cells
which HLA is behcet’s disease linked to?
HLA-B51
