Pharmacology and Microbiology Flashcards

1
Q

How are step pneumonia resistant to phagocytosis?

A

Due to capsular polysaccharide layer

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2
Q

Treatment of actinomyces and nocardia?

A

SNAP
Actinomyces; Sulphonamide
Nocardia; Penicillin

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3
Q

Legionella.. Type of bacteria? Agar and stain ?
What electrolyte imbalance occurs?

A

Legionella gram negative
Silver stain
Grows on charcoal yeast extract medium with iron and cysteine
Hyponatremia

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4
Q

Pseudomonas Aeruginosa - type of bacteria? What does it produce - PEEP

A

Aerobic
Gram negative
Produces:
Phospholipase
ENdotoxin
Exotoxin A inhibits EF2
Pigments; Pyocyanin - blue /green

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5
Q

Examples of Exotoxin bacteria?

A

Botulin Toxin
Diphtheria cholera

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6
Q

Examples of endotoxin bacteria ? What does they activate.
What are more toxic - endo or exotoxin

A

Endotoxin
outter cell memberane of most gram negative bacteria
Lipid A component of LPS - sturcutural part of lps
Bacterial chromospme
Festure include fever, shock, DIC
Indices TNF, IL1 and Il6,
Poorly antigenic
No toxoids formed and no vaccinable available
Stable at 100eg for 1 hr
Menigoccous

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7
Q

All DNA are double stranded except

A

Parovirus

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8
Q

All RNA are single stranded except

A

Reovirdiae

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9
Q

Features of DNA

A

DSDNA
Linear genome
Are isocahederal - except pox
Replicate in nucleus - indenpent f RNA polymerase

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10
Q

Viral replication process?

A

Adhesion
-collision
-electrostatic attachement
-host cell replication
Penetration
Capsid removal by host cell
Nucleic acid replication

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11
Q

HSV binds to what glycoprotein to enter host ?

A

Binding to gD receptors include:
Nectin 1; membrane of igG superfamily
Nectin 2; HVEM aka herpes viral entry mediator - TNF superfamily -facilitate penetration of capsid into host cell

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12
Q

HSV1 -
HSV2

A

1 - cold sores
2 - genital sores

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13
Q

Vaccination for herpes zoster ? type of vaccine

A

Zosatrix - live attenuated vaccine. not used in IC people. One dose required
Shingarix - used in IC people
contains VZV glycoprotein
Vaccine effocency - Phase 3: 2 doses 97% in >90yo, 91% in 71yo

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14
Q

Shingrx efficacy after one dose and two dose

A

One dose 57
Two dose 70

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15
Q

Adenovirus - type of bacteria?
Subtype that leads to
epidemic keratoconjunctivitis
Pharyngoconjunctivitis fever
Acute haemorrhagic conjunctivitis
Acute follicular

A

epidemic keratoconjunctivitis 8.9.27
Pharyngoconjunctivitis fever 3,7
Acute haemorrhagic conjunctivitis 11,21
Acute follicular 1-10

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16
Q

CMV affects on the eye, describe the histology, what it binds to ?

A

Causes aids retinitis; show full thickness retinal necrosis, affects the retina prematurely at posterior pole
Features include; haemorrhage, exudates, cotton wool spots, vision lost

Owl eye includson bodies
Latent in mononuclear cells
Binds to integrin - heparin sulphate

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17
Q

Features of the epidemic keratoconjunctivitis?

A

Unilateral onset of preauricular lymphadenopathy
nilateral follicular conjunctivitis
Epithelial opactities fade in 4 week
Subepithelial opactiies –> 2 year

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18
Q

Time course of epidemic keratoconjunctivitis?

A

Foreign body sensation, periorbital ain, Diffuse superficial keratitis,
Subepithelial opactieis form under focal epithelal infilterates

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19
Q

Diagnosis of epidemic keratoconjunctivitis?

A

Immunoassay

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20
Q

Rubella ? rash? other name for it ? Infectivity
Transmission
Incubation

A

Blueberry muffin rash
3 days pre and post rash
Respiratory
12-24 days

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21
Q

Congenial features of Rubella ?

A

Pigmentary retinopathy
Catract
Glaucoma
Cloudy corena
Micro-ophthalmia

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22
Q

Measles - type of virus
Transmission
Treatment
Infectivity ?

A

ssRNA
Nasopharygneal secretions
Mother to child
4 days pre and post rash

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23
Q

Severe complication of Measles ?

A

Subacute sclerotising pancephalitis - unvaccinated children get disease 6-8 yeaer after infection

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24
Q

Symptoms of subacute scleroising pancephalitis
acute
delayed

A

Acute:
Memory impairment, behavioural delay, visual impairment

Delayed: Myoclonos, spastic, paresis, dementia, death 1-3 eyars

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25
Q

In subacute scleroising pancephalitis do nerological or ocular feature occur first ?
and by how many years ?

A

Ocular features by 2 year
feautres includ; focal retinits, RPE change, Pailloedema, OD swelling, optic atrophy,

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26
Q

Diagnosis of subacute scleroising pancephalitis do neurological

A

EEG abnormality
IgG antibody in plasma/ CSF

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27
Q

What are the 3 structural genes in HIV?

A

Env - gp120, gp41
Gag - p24 and p17
POL - TIP

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28
Q

Disease that occur when the CD 4is
<500
<200
<100
<50

A

<500 - candida, EBV, HPV,TB
<200 - pneumocystis pneumonia - ground glass
<100 - CMV, toxoplasmosis, cryptococcus neoformans
<50 - mycobacterium avium

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29
Q

Cancer associated wit hHIV most common and second most common

A

Most common - Kaposi
Second: Non Hodgkin B cell lymphoma

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29
Q

chlamydia?
2 forms

A

Obligate intercellular parasite of mucsal epithelial cells
2 form: InfectiousL Elementary - outside of host
Reproduction: reticulate; inside of eukaryote, replicate by binary fission

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30
Q

Infectious conjunctivitis more common;
children
Adult

A

Child: bacteria ;HIB and strep
Adult: Adenovirus, herpes and herpes zoster

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31
Q

Immune mechanism in Helminth

A

Mast cell and IgE

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32
Q

Bacteria and virus

A

IgG, complemetns, neutrophils

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33
Q

Pneumonia and encapsulated organism ?

A

IgM, Macrophage and complement

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34
Q

Myobacterium

A

Cytotoxic T cells, macrophages, delayed hypersensitivity

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35
Q

Sphyllis

A

Macrophages, delayed hypersensitivity

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36
Q

Most common anaerobe seen in chronic endophthalmitis ?

A

Propionibacterium

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37
Q

Bacteria most common with older people and type of bacteria?

A

Gram Negative
Demodex folliculorm
Demodex Brevis

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38
Q

Toxoplasmosis ? causes what uveitis
How is it transmitted ?
What are the 3 forms?

A

Posterior uveitis
Transmitted via feline
3 forms;
Oocyst - contains sporozoites 10-12 micrometer
Tachyzoite - infectious form 4-8 micrometer
Bradyzoite - latent in tissue 10-200 micrometer

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39
Q

Bacterial protein synthesis inhibitors at the 50s subunit

A

Cephalosporin
Clindamycin
Linezolid
Macrolides; Azithro,

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40
Q

Bacterial protein synthesis inhibitors at the 50s subunit

A

Aminoglycosides; gent
Tetracyclines; tetra, doxy, erythromycin

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40
Q

DNA Gyrase inhibitor binding to what? Examples

A

Work by binding to topi II and IV Fluroquinolone
Quinolone

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41
Q

Peptidoglycan crosslinking inhibitors ?

A

Penicillin
Cephalosporin

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42
Q

1-4 generation cepharlosporin are resistant against

A

LAME
Listeria
MRSA
Enterococci
Atypical - chlamydia and mycobacteria

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43
Q

Benefit of 3rd generations cephalosporin? and examples

A

Crosses BBB
effective against gram -ve
Example; Ceftazidine; Psuedomonads
Ceftriaxone: meningitis gonorrhoea

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44
Q

Mechanism of action of chloroquine?
What parasite is toxic to it ?
SE

A

Prevents the break down of haem. Haem builds up and is toxic to plasmodia
P. Falcifarum resistance by intracellular pump.
Retinioathy
Rash

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45
Q

MOA of amphoceterin?

A

Affect cell memberane integerity. Binds to ergosterol and form pores which allows leakage of electrolyes.
CLinical use; serous systemic myocese

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46
Q

MOA of azoles

A

Inhibit fungal ergoesterol synthesis by inhibiting cyp450 tat required to convert lanesterol to ergsterol

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47
Q

MOA of grisefluvin?

A

Interferese with microtubules function –> disrupts mitosis deposits in keratin rich tissues

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48
Q

Inhibitions of nucleic acid synthesis in viral cells

A

Inhibitions of nucleic acid synthesis in viral cells
Guanosine analogs; Acyclovir/ Famcloir, Ganclovir
Viral DNA polymerase inhibitor; Cidofvir, Foscarnet

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49
Q

Guanosine analogs; Acyclovir/ Famcloir, Ganclovir MOA

A

Monophosphorlyate by HSV and VZV thymidine kinase. Not phosphorylated in uninfected cells . Not effective against CMV as does not have any TK.

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50
Q

Guanosine analogs used for CMV and MOA

A

Gangcliovir
MOA guanosine analog 5’ monophosphate formed by CMV viral kinase

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51
Q

Are staph and strep anaerobic or aerobic

A

Gram positive cocci
Staphylococcus-occurs in clusters
Streptococcus-occurs in chains
All gram positive cocci are aerobes

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52
Q

Gram positive bacilli

A

Gram positive bacilli
Aerobes-bacillus
Anaerobes
Sporing-Clostridium
Non sporing-Actinomycetes, Propionibacterium

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53
Q

Foscarnet antiviral MOA ?

A

Viral DNA / RNA polymerase inhibitor and HIV reverse transcriptase inhibitors. Binds to pyrophosphate binding site of enzyme. Does not requires

FOScarnet=pyroFOSphate analog

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54
Q

What is the typical time period from inoculation to symptoms in Adult chlamydial conjunctivitis ?

A

1-2 weeks

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55
Q

Vancomycin
MOA
Effective against
Use

A

Vancomycin is a glycopeptide antibiotic

2) Mechanism of action: Binds to pentapeptide chains and prevents the assembly of peptidoglycans in the cell wall causing cell lysis

3) Bactericidal activity against gram-positive organism

4) Use: Intravitreal treatment of endophthalmitis

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56
Q

What are the virulence factor of acathanomeba

A

Virulence factors involve adhesion capabilities to the ocular surface
Mannose-binding lectin is associated with virulence and has a higher level of expression in pathogenic strains
Mannose induced protein (MIP) is a protease with collagenase activity that can damage the cornea epithelium.

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57
Q

What is the classification of acanthamoeba?

A

Acanthamoeba Species Classification:
Species classified by morphological characteristics and cyst size
Alternatively, classified by 18S ribosomal RNA gene sequencing
Genotype Distribution:
23 genotypes identified (T1-T23) using 18S ribosomal RNA sequencing.
T4 genotype is the most common causative agent of Acanthamoeba keratitis (AK)
Other genotypes implicated in AK include T2, T5, T6, T10, T11, T12, and T1

58
Q

Which of these is found in adult C.trachomatis conjunctivitis but not neonates ?

Greater discharge
Membrane formation
Follicular reaction
Hyperaemia

A

Follicular reaction - children dont have any lymphoid tissue

59
Q

Three forms of toxoplasmosis and size

A

4) Three forms:
Oocyst/ soil form, contains sporozoites ( between 10-12 micrometres)
Tachyzoite ( between 4 to 8 micrometres)
This is the infectious form
Tissue cyst/ latent form (between 10-200 micrometres)
Can contain up to 3000 bradyzoites

60
Q

Propionibacterium acnes anerobic or aerobic ?

A

Anaerobic

60
Q

What type of organism is toxocariasis caused by?

A

Round worms

61
Q

Where can viral replication take place ?

A

Nucleus or cytoplasm

62
Q

RNA viral replication process.. what type of replication bodies?

A

RNA virus replication occurs in cytoplasm which produces cystoplasmic inclusion, and uses reverse transcriptase to make DNA from RNA template . RNA virus are unable to use host cell enzymes and use reverse transcriptase to synthesize their own proteins.

63
Q

RNA versus DNA replication bodies?

A

DNA - inclusion bodes
RNA - cytoplasmic bodies

64
Q

Antimetabolites example? what phase of the cell cycle do they affect ?

A

S phase
As Zara says FU to meth

Azathioprine - antimetabolite precursor of 6 mercaptopurine inhibits lymphocyte proliferation by blocking nucleotide synthesis
5FU - pyrimidine analog bioactivated to 5Fdump -> thymidine synthetase inhibitor inhibits DNA synthetase
Methotrexate - Folate syntheses antimetabolite
Mitomycin inhibits DNA synthesis

65
Q

The relationship between potency and duration of action for

A

Duration of action
ACH

HCA

66
Q

Drugs and their MOA for myelosuppression

A

Mycophenolate Mofetil: reversibly inhibits IMP dehydrogenase preventing purine
synthesis if B and T cells

Azathioprine - Purine analogue
It is converted to Mercaptopurine.
Conversion of metabolically active 6 mercaptopurine into 6-thioguanine inhibits cell proliferation
Inhibit purine synthesis, blocks RNA and DNA synthesis

4) Metabolism:
6 mercaptopurine is metabolized by thiopurine methyltransferase.
TPMT levels should be measured when using Azathioprine.
A non-functional TPMT gene can lead to life-threatening myelosuppression (if 2 non-functional alleles).
In the heterozygotes, there is increased risk of myelosuppression
6MP inhibited by allopurinol –> increase toxicity of the azathioprine

5FU -> Pyrimidine analog bioactivated to 5Fdump –> thymidylate synthesize inhibitor –> Inhibit DNA synthese

Mitomycin C -> Inhibits DNA synthesase

67
Q

MOA of isoniazid ?

A

Inhibits myolic acid. Bacterial catalase-peroxidase (encoded by katG) need to convert INH to active metabolite

68
Q

Ethambutol - eat carbh

A

Inhibits carb polymerization f mycobacterium wall by blocking arabinosyltransferase

69
Q

Rifampicin ?

A

Inhibits RNA polymerase
CYP45- inducer

70
Q

Difference between clindamycin and metronidazole ?

A

Clinda-treats above diaphragm
Metro - treats below the diaphragm

71
Q

Tetracycline is effective against ?

A

Borellia Burgofdi
M. Pneumonia
Drugs ability to accumalate intracellularly; very effective against rickettsia and chlamydia

72
Q

Linezoid is effective against what bacteria ?

A

MRSA and VRE

73
Q

Macrolides are effective against what bacteria?

A

Atypicals; mycoplasma, chlamydia, legionella
STI
Gram +ve cocci
B pertussis

74
Q

Aminoglycoside are ineffective against what bacteria ?

A

Anaerobes

75
Q

Vancomycin is effective against what bacteria ?

A

MRSA
S. Epidermis,
Clostridium difficle

76
Q

1-4 generation cephalosporin are not effectvie against what bacteria ?

A

LAME
Listeria
Atypicals - mycoplsma, chlamydia
Myoplasma/MRSA
Enterocci

77
Q

Piperacillin is effective against what bacteria?

A

Pseudomonas

78
Q

Penicillin sensitive bacteria against ? Examples include?

A

Gram positive bacteria - cocci
H.influenzae, H.pylori, E.coli, Entercocci, Listeria, Proteus mirabilis, salmonella, shigella

79
Q

Species that can penetrate the cornea

A

Corynebacterium diphtheriae, Haemophilus influenzae, Neisseria gonorrhoea, Neisseria meningitidis, and Listeria species.

80
Q

Antimicrobials to avoid in pregnancy ?

A

Sulphonamide
Aminoglycoside
Fluroquinolones
Clarithromycin
Tetracycline
Ribavirin
Grisofleuci
CHloramphenicol

SAFe Children Take Really good care

81
Q

Nuclear condensation ?

A

Phyknosis

82
Q

Nuclear fragmentation caused by endonuclease mediated cleavage

A

Karyorrhexis

83
Q

Nuclear discoloration ?

A

Karyolisis

84
Q

Lipophilic metabolism of drugs; 2x phases and examples of the processes that occur at each phase?

A

Phase I - slightly polar metabolites. Reduction, Oxidation, hydrolysis
Phase II - very polar

85
Q

ideal viscosity ?
WHat happens if it is too high
Agents to increase viscosity ?

A

12 -15 centipost
too high excessive blinking
Methylcellulose, polyvinyl alcohol

86
Q

Difference between a1 and b2?

A

Alpha 1 decrease IOP
Beta 2 - increase IOP

87
Q

Anesthetic used in corneal scrape ?

A

proxymetacaine/ procaine

88
Q

Examples of biologics?

A

Etanercept - Decoy TNFalpha receptor , inhibits IgG1 and F2 - produced by recombinant DNA

89
Q

MOA of Etanercfept, produced by ?

A

Etanercept - Decoy TNFalpha receptor , inhibits IgG1 and F2 - produced by recombinant DNA

90
Q

MOA ecluizmab?

A

Comlement protein C5, increased risk of meningoccal infection

91
Q

MOA of infliximab / adalimumab?

A

Anti TNFa monoclonal antibody

92
Q

MOA of rituximab?

A

Binds t CP 20. Infusion rxn due to cytokine release following rxn with Bcells

93
Q

MOA of toxoluzimb? used to treat

A

Binds competitively to IL1 and IL6

94
Q

Tacrolimus MOA ?

A

Inhibits NF T cells, Ca2+, Il2 and Thelper

95
Q

MOA of cyclophosphamide ?

A

Nitrogen mustard alkylating agent, binds to DNA in cells with low levels of aldehyde dehydrogenase

96
Q

lipophilic versus hydrophilic steroids?

A

Lipophilic - acetate - more potent
Hydro - phosphate - less potent

97
Q

Dresden protocol for keratoconus crosslinking - % and what UV ?

A

1) Dresden Protocol-standard treatment protocol for keratoconus. Other concentrations of riboflavin are experimental.
Instillation of topical anaesthetic
Debride central 7-9mm of corneal epithelium
0.1% riboflavin 5 phosphate, 20% dextra solution every 5 minutes for 30 minutes
Exposure to UVA ( 370nm, 3mw/cm2) for 30 minutes while instilling above drops
Apply topical antibiotics and BCL at the end.

98
Q

You have a Parkinson’s patient who is complaining of severe dry eyes. You note from his ophthalmic history that he developed angle closure glaucoma a few months ago. Which of the following medications is most likely to be to associated with his symptoms?

Benztropine
Bromocriptine
Carbidopa
Levodopa
Selegiline

A

Benztotropine

99
Q

MOA of entacapone?
Amantadine and the effect it has on the eye ?
Dopamine agonist and example
Monoamine Oxidase inhibitor example?
Anticholinergic medication example

A

Treatment:
Levodopa and carbidopa
Carbidopa delays conversion of levodopa to dopamine until it reaches the brain
Entacapone
Catechol O-methyltransferase inhibitor, extend duration of levodopa
Amantadine
Antiviral but can be used in early stages of disease
Associated with cornea infiltrate and cornea oedema
Dopamine agonist such as:
Bromocriptine, pramipexole, ropinerole, rotigotine, apomorphine
Monoamine oxidase inhibitors such as:
Selegiline, rasagiline, safinamide
Anticholinergic drugs
For controlling tremor, rigidity
Examples: Trihexyphenidyl, benztropine

100
Q

Which of the following best describes adalimumab?

Fully human anti-TNF alpha monoclonal antibody
Genetically engineered chimeric murine/ human monoclonal antibody
Mouse-derived chimeric monoclonal antibody against TNF-alpha
Recombinant human antibody against TNF-alpha
Fusion protein consisting of CTLA4

A

Which of the following best describes adalimumab?

Fully human anti-TNF alpha monoclonal antibody

101
Q

MOA of adalimumab - what receptors does it bind to ?
is it used in non infectious or infectious uveitis ?
SE of adliumab?

A

Mechanism of action:
Blocks interaction of TNF alpha with p75, p55 cell surface receptors
Non infectios uvieits - GCA, JIA,

SE Most common side effect are related to injection site reaction with pain, redness, swelling, itching, bruising
Drug induced lupus
Multiple sclerosis
Skin cancer
Basal cell carcinoma, squamous cell carcinoma

102
Q

Which of the following is a mast cell stabiliser + eosinophil suppressor used to treat allergies?

A

Lodoxamide

103
Q

Cromoglycate?

A

Mast cell stabiliser
Cromoglycate

104
Q

Dosage of pilocarpine in presbyopa and adies pupil

A

Pilocarpine 1.25% has recently been approved by the US FDA as a treatment for presbyopia

Pilocarpine 0.125% is used as part of pharmacological testing for denervation hypersensivity to diagnose Adie’s pupi

105
Q

Ranibizumab binds to what ?
Half life
Profile

A

) Ranibizumab
Also known as Lucentis
Humanized Fab fragment of monoclonal antibody
High affinity to VEGF A
Binds to soluble VEGF isoforms 110,121, 165
Also binds to tissue-bound isoforms 189,206
Short intravitreal half life of 2-4 days, rapid systemic clearance, good safety profile
Tend to be used as reference standard for treatment

106
Q

SE of pilocarpine

A

) Side effects:
Conjunctival toxicity
Iris Cyst
Cataract
Systemic parasympathetic effect:
Sweating
Salivation
Bradycardi

107
Q

Dosage and form of administration of foscarent

A

intravitreal foscarnet 2.4mg/0.1ml can be used as treatment for acute retinal necrosis

108
Q

Dosage of acyclovir?

A

Acyclovir ointment is available in 3% doses

109
Q

Dosage of ganciclovir ophthalmic gel?

A

Ganciclovir ophthalmic gel is available in 0.15% dose

110
Q

Moa of acyclovir and ganclovir

A

Acyclic analogue of guanosine
Mechanism of action:
Inhibition of viral DNA polymerase following viral thymidine kinase phosphorylation, its action is catalysed by thymidine kinase.

111
Q

Muscarinic antagonist examples

A

1) Atropine and Cyclopentolate
Muscarinic antagonist:
Blocks action of acetylcholine on muscarinic receptors
Causes dilation with the paralysis of the iris sphincter.

3) Duration of action :
Cyclopentolate:
1-2 days
Homatropine:
3 days
Atropine sulfate:
7-14 days

112
Q

Duration of action of Muscarinic antagonist
CHA

A

CHAT
Duration of action :
Cyclopentolate-maximal action 30 mins, duration 12-24 hours
Homatropine-maximal mydriasis at 40 mins, duration of action 1-2 days
Atropine sulphate-maximal mydriasis at 40 mins, duration of action 7-10 days
Tropicamide-maximal action 20 mins, duration 3-4 hours

113
Q

What are the uses of muscarinic antagonist ?

A

2) Uses:
Dilated fundal exam
Prevention of iris-lens adhesion ( posterior synechiae)
Paralysis of the ciliary muscle
Inhibits accommodation for refraction in children
Malignant glaucoma/ Aqueous misdirection ( atropine)

114
Q

Factors that affect the degree of accommodation of the cycloplegic medication?

A

Degree of accommodation affected by
Iris colour
Patient age
Number of drops applied

115
Q

Effect of cycloplegic on anterior uveitits?

A

Effect on anterior uveitis:
Paralyses inflamed muscle
Reduce vascular permeability
Less inflammatory mediators
Breaks posterior synaechiae by inducing dilation

116
Q

Cell barriers at the corneal epithelium and endothelium ?

A

Epithelium: desmosomes
Endothelium: gap junctions

117
Q

2x H1 blocker + mast cell stabiliser:

A

Nedocromil
Opatanol

118
Q

Mast cell stabiliser and eosinophil inhibitor?

A

Liminoid

119
Q

VFd with vagibatrin

A

Visual field defect
Bilateral, concentric, predominantly nasal

120
Q

Rho kinase
size, type of nucleic acid, where is it found?
3 main classes?

A

Rho kinase ( ROCK):
Is a Serine/ threonine kinase
Downstream effector of Rho GTPase

2) Rho family of GTPase:
Small 21kDa signaling G proteins
Found in cytoplasm
3 main classes-Rho, Rac, Cdc42

121
Q

Arachidonic acid is converted into prostaglandins and thromboxane by >

A

Arachidonic acid is converted into prostaglandins and thromboxanes by cyclo-oxygenase.

122
Q

The function of I2 , F2 alpha, and E2

A

Prostaglandin actions:
I2:
Vasodilation, decreases platelet adhesion
F2alpha:
Contraction of bronchial smooth muscle
E2:
Vasodilation, bronchodilation, the release of pituitary hormones, the release of insulin and contraction of the uterus

123
Q

The purpose of phase I versus phase II elimination of drugs?

A

1) Drug metabolism has two different stages and occur mainly in the liver

2) Stage I ( Oxidation, Reduction, Hydrolysis):
Affected by cytochrome p450
After stage I metabolism the drug can become inactive, or its metabolites become active (original substance known as prodrug)

3) Stage II ( Conjugation):
Occurs with glucuronic acid, glycine, glutamine and sulphate acetate
The purpose is to make drug or its metabolite soluble to be excreted in urine

124
Q

Dosage of CAI topical and oral/iv

A

8) Topical form: Dorzolamide/ Brinzolamide
Usually given 2-3 times/day
Reduce IOP by 14-17%

9) Topical adverse effects: Burning sensation, punctate keratitis and bitter taste

10) Oral/ IV form : Acetazolamide ( usually 500mg BD or 250mg up to 4 times/day). It is a type of sulfonamide.

125
Q

Ciliary body needs to be inhibited by what percent before illicting an effect?

A

Carbonic anhydrase in the ciliary body needs to be 99% inhibited to reduce aqueous flow.

126
Q

Topical adverse effects of CAI inhibitors

A

Topical adverse effects: Burning sensation, punctate keratitis and bitter taste

127
Q

difference in MOA between infliximab and adaliumab

A

Infliximab interferes with binding of TNF-alpha to TNFr1 and TNFr2
Adaliumab interferes with binds by TNFa at the p75 an P55 receptors

128
Q

Difference between Pegcetacoplan and avainacted pegol?
What are they used to treat?

A

Pegcetacoplan targets C3 and C3b, while avacincaptad pegol targets C5.
Used to treat - Geographic atrophy of AMD - late sign

129
Q

Alpha 1 agonist increase or decrease IOP?

A

Decrease

130
Q

Your uveitis consultant has decided to start a patient with panuveitis on second-line immunosuppressive drugs. The patient is a 25 year old female who is trying for pregnancy, which of the following would you consider?

Azathioprine
Mycophenolate Mofetil
Methotrexate
Cyclophosphamide
Rituximab

A

Azathiopurine

131
Q

Washout period of brimonidine?

A

Brimonidine ( alpha 2 agonist)
5 weeks

132
Q

Bacteria associated with ocular rosasea

A

Some research has also shown a possible link between rosacea and the Helicobacter pylori bacteria.

133
Q

Benzalkonium chloride effect of drug absorption and how?

A

Benzalkonium chloride increase ocular absorption of drug by decreasing corneal integrity

134
Q

Drugs are pass through the cornea by?

A

diffusion

135
Q

A drug that inhibits nuclear factor of activated T cells?

A

Tacrolimus

136
Q

MOA of glucocorticoids

A

Mechanism of action:
Penetrate cell membrane
Bind to receptors in cytosol
Translocation of glucocorticoid receptor complex to nuclear binding sites
Induce or suppress mRNA.

137
Q

Pilocarpine act on what type of muscle in the ciliary body?

A

Contraction of the longitudinal ciliary muscle fibres causes tension on the scleral spur and improves outflow.

138
Q

What form does the LA come and what happens when it meets the pH of the eye?

A

Usually supplied in hydrochloride salt form/ protonated-becomes unprotonated when exposed to human tissue at pH7.4

139
Q

side effect of tetracaine ?

A

Epithelial toxicity

140
Q

The size of the conjunctival sac

A

The conjunctival sac has a capacity of 15-30ul.

141
Q

Cationic surfaces increase or decrease absorption ?

A

Decrease absorption

142
Q

Which of the following topical steroid is available as a preservative free ophthalmic preparation?

A

Dexamethasone sodium phosphate