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.