Test
MD25 Controlling release in vivo
Este test tiene tipos de pregunta que se abren en el reproductor de siempre.
Preguntas del test (13)
1Temporal control could be important for drugs which:
• Have a time-dependent [blank_start]mechanism of action[blank_end] eg some cytotoxic drugs, [blank_start]antibiotics[blank_end]
• Are [blank_start]unstable[blank_end] (short half life)
• Need continuous [blank_start]exposure[blank_end]
• Need [blank_start]multiple[blank_end] short periods of exposure- Amechanism of action
- Bantibiotics
- Cunstable
- Dexposure
- Emultiple
2Spatial control could be important for drugs which are:
• Highly [blank_start]toxic[blank_end], and have a [blank_start]narrow[blank_end] therapeutic window
• Readily [blank_start]metabolized or excreted[blank_end]
• Have a [blank_start]concentration-dependent[blank_end] mechanism of action- Atoxic
- Bnarrow
- Cmetabolized or excreted
- Dconcentration-dependent
3A time-dependent mechanism of action means that the amount of [blank_start]time spent[blank_end] above the [blank_start]therapeutic level[blank_end] is more important than the peak drug concentration. Examples are some classes of antibiotics, and [blank_start]cycle specific cytotoxic[blank_end] cancer drugs.
A concentration-dependent mechanism of action means [blank_start]peak concentration[blank_end] reached is more important than time spent above therapeutic level. Examples are [blank_start]non-cycle specific[blank_end] cytotoxic drugs (chemotherapy) & [blank_start]concentration-dependent killing[blank_end] antibiotics. Also known as ‘[blank_start]log kill[blank_end]’ agents.- Atime spent
- Btherapeutic level
- Ccycle specific cytotoxic
- Dpeak concentration
- Enon-cycle specific
- Fconcentration-dependent killing
- Glog kill
4As dose is increased, non-cycle specific cytotoxic drugs become more effective.
- AVerdadero
- BFalso
5As duration of drug exposure is increased, cycle specific cytotoxic drugs become more effective.
- AVerdadero
- BFalso
6We can achieve controlled release in vivo by using prodrugs, IDDS, nanomedicines and nanoformulations. We can use nano-scale materials for therapeutic benefit, to modify [blank_start]kinetics[blank_end] of release (temporal control) – [blank_start]sustained or pulsatile[blank_end], [blank_start]location[blank_end] of release (spatial control) – crossing [blank_start]barriers[blank_end] (eg BBB, cell membrane, nuclear membrane), or at tissue [blank_start]site[blank_end] (eg tumor). We can therefore increase [blank_start]therapy efficacy[blank_end] and decrease [blank_start]side effects[blank_end] (drug toxicity and antibiotic resistance).
- Akinetics
- Bsustained or pulsatile
- Clocation
- Dbarriers
- Esite
- Ftherapy efficacy
- Gside effects
7Why use Nanoparticles?
• Increase [blank_start]solubility[blank_end]
• [blank_start]Protect[blank_end] active(s)
• [blank_start]Co-delivery[blank_end] of multiple drugs
• To control [blank_start]time[blank_end] of release (temporal)
• To control [blank_start]location[blank_end] of release (spatial)- Asolubility
- BProtect
- CCo-delivery
- Dtime
- Elocation
8The [blank_start]immune[blank_end] system has evolved to recognise and take up nm – µm complexes. This is bad for [blank_start]drugs[blank_end], though good for [blank_start]vaccines[blank_end]. Commonly we use ‘[blank_start]stealth[blank_end]’ technologies, eg coating NPs with [blank_start]polyethylene glycol[blank_end]; known as PEGylation.
- Aimmune
- Bdrugs
- Cvaccines
- Dstealth
- Epolyethylene glycol
9Tumour blood vessels are [blank_start]leaky[blank_end] so we can give [blank_start]passive[blank_end] tumor specific delivery by making NPs too [blank_start]large[blank_end] to leak through healthy vessels, but which will [blank_start]diffuse[blank_end] into tumors. This does depend on [blank_start]pressure[blank_end] inside the tumor - it may get leakage back out of the tumor into the blood vessel.
- Aleaky
- Bpassive
- Clarge
- Ddiffuse
- Epressure
10The half life of Peg-Dox is 55 hours, compared to 10 min for Dox, so it does
not need to be given by continuous infusion (CI).- AVerdadero
- BFalso
11We can achieve passive spatial control by modifying the [blank_start]intrinsic[blank_end] properties of the nanoformulation, such as nanoparticle [blank_start]size, shape, charge, and hydrophobicity[blank_end].
We can achieve active spatial control by placing [blank_start]external markers[blank_end] on our liposomes/nanoparticles like [blank_start]antibodies, aptamers, and ligands[blank_end].- Aintrinsic
- Bsize, shape, charge, and hydrophobicity
- Cexternal markers
- Dantibodies, aptamers, and ligands
12Temporal control passive release:
Delivering drug in a nanoformulation can increase [blank_start]circulation time[blank_end] and give [blank_start]sustained[blank_end] release, if we can [blank_start]avoid[blank_end] uptake by the immune system. Release will depend on particle [blank_start]composition & stability[blank_end], and can be via [blank_start]diffusion, erosion, or osmotic pumping[blank_end].
Temporal Control active release:
[blank_start]Stimuli responsive[blank_end] nanoformulations which release drug upon [blank_start]exposure[blank_end] to an endogenous or exogenous stimuli.- Acirculation time
- Bsustained
- Cavoid
- Dcomposition & stability
- Ediffusion, erosion, or osmotic pumping
- FStimuli responsive
- Gexposure
13Temporal control: Passive release is [blank_start]triphasic:[blank_end]
1. Burst of drug at/near [blank_start]surface[blank_end]
2. Slow release by [blank_start]diffusion[blank_end]
3. Burst due to [blank_start]erosion, breakdown, degradation[blank_end]- Atriphasic
- Bsurface
- Cdiffusion
- Derosion, breakdown, degradation
Información
- Descripción
- (Medicines) PHCY211 Test sobre MD25 Controlling release in vivo, creado por Mer Scott el 27/05/2018.
- Autor
- Mer Scott
- Idioma
- English
- Visitas
- 12
- Etiquetas
- Valoración
- Aún sin valoraciones Valora este test