definitions Flashcards
pathogen
organism that is capable of or causes disease
commensal
organism that colonises the host but causes no disease in normal circumstances
opportunistic pathogen
microbe that only causes disease if the host defences are compromised
pathogenicity
the degree to which an organism is pathogenic
asymptomatic carriage
when a pathogen is carried harmlessly at a tissue site where it causes no disease
endotoxin
component of the outer membrane of bacteria
exotoxin
secreted proteins of bacteria
pre-patent period
the interval between infection and the appearance of eggs in stool
infectivity
the ability to become established in a host
virulence
the ability to cause disease once established
invasiveness
the capacity to penetrate mucosal surfaces to reach normally sterile sites
antigenic drift
spontaneous mutations occur gradually, giving minor changed in haemagglutinin and neuraminidase
antigenic shift
sudden emergence of new subtype different to that of preceding virus
antibiotic
agents produced by micro organisms that kill or inhibit growth of other microorganisms
usually means antibacterial
bacteriostatic
prevents growth of bacteria
bactericidal
kills bacteria
minimum inhibitory concentration
conc. required to stop bacteria from multiplying
minimum bactericidal concentration
lowest conc. of antibacterial agent required to kill a particular form of bacterium
pharmacokinetics
movement of a drug from its administration site to place of its pharmacologic activity and then its elimination from the body
acquired resistance
bacterium that was previously susceptible to an antibiotic now obtains the ability to resist that antibiotics activity
conjugation
sharing of extra-chromosomal DNA plasmids
transduction
insertion of bacterial DNA by bacteriophages
transformation
picked up naked DNA
cell tropism
cells of a host support growth of a particular virus or bacterium
confidentiality
right of an individual to have persona, identifiable medical information kept private
such info should only be available to the physician on record and other health care personnel as necessary
acute HIV
condition that can develop as early as two to four weeks after someone contracts HIV
seroconversion
the period of time during which HIV antibodies develop and become detectable
clinical latency
state or period of HIV living or developing in a host without producing clinical symptoms
AIDS
CD4 is <200 or an AIDS defining illness is present
AIDS defining illness
illnesses directly associated with advanced HIV
embolism
mass of material in the vascular system able to become lodged within the vessel and block it
ischaemia
reduction in blood flow to a tissue without any other implications- inadequate blood supply
infarction
reduction in blood flow resulting in subsequent local cell death
atheroma
pathology of arteries in which there is deposition of lipids in the arterial wall with surrounding fibrosis and chronic inflammation
apoptosis
programmed cell death of a single cell
necrosis
unprogrammed cell death of a large number of cells due to an adverse event
genetic disease
disease that occurs primarily from a genetic abnormality
inherited disease
caused by an inherited genetic abnormality
single gene disorder
abnormality of a single gene that causes the disease
dominant
disease is present where there is only one copy of the abnormal gene- e.g. Huntington’s
recessive
only expressed if both copies of the gene are abnormal
co-dominant
both alleles are expressed- e.g. AB blood group
autosomal
occurring on the non-sex chromosomes
sex-linked
occur on the sex chromosomes
polygenic disorder
diseases that are a result of the interaction of several different genes, usually on different chromosomes
congenital
diseases present at birth
acquired
diseases or medical condition developed or originating after birth
hypertrophy
increase in size of tissue caused by an increase in the size of the cells without an increase in the number of cells
hyperplasia
increased growth of a tissue caused by an increase in the number of cells
atrophy
decrease in size of a tissue caused by a decrease in number of constituent cells and/or a decrease in their size
metaplasia
the reversible transformation of one mature cell type into another fully differentiated cell type
dysplasia
premalignant condition characterised by increased growth, cellular atypia and decreased differentiation
ageing
progressive losses of various functions and accumulation of diseases
carcinogenesis
the transformation of normal cells to neoplastic cells through permanent genetic alterations or mutations
carcinogenic
cancer causing
oncogenic
tumour causing
cancer
genetic term for malignant tumour
neoplasm
a lesion resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after the initiating stimulus has been removed
benign neoplasm
generally slow growing lesions which closely resemble the parent tissue and remain localised
malignant neoplasm
have the capacity to invade the surrounding tissue, grow rapidly and show a variable resemblance to the parent tissue
histogenesis
the specific cell of origin of a tumour
papilloma
benign tumour of non-glandular, non-secretory epithelium
adenomas
benign tumour of glandular, secretory epithelium
adenocarcinomas
carcinomas of glandular epithelium
sarcoma
malignant connective tusse neoplasms
anaplastic
cell type of origin is unknown
metastasis
process by which a malignant tumour spreads from its primary site to produce secondary tumours
thrombosis
the formation of a solid mass from blood constituents in an intact vessel in a living person
carcinoma
malignant tumour of epithelial cells
partial agonists
drugs that bind to and activate a receptor but only have partial efficacy
affinity
how well a ligand binds to a receptor
efficacy
how well a ligand activates the receptor- maximum response achievable from the drug
potency
measure of drug activity expressed in terms of the amount required to produce an effect of a given intensity
allosteric modulation
substance that indirectly influences the effects of a primary ligand that directly activates or deactivates the function of a target protein
inverse agonism
agent that binds to same receptor as an agonist but induces a pharmacological response opposite of the agonist
tolerance
reduction in the drugs effect over time due to prolonged use
enzyme inhibitor
molecule that binds to an enzyme and decreases its activity
xenobiotics
compounds foreign to an organisms normal biochemistry such as any drug or poison
absorption
process of transfer from the site of administration into the general or systemic circulation
half life
time taken for a conc. to reduce by a half
bioavailability
fraction of the administered drug that reaches the systemic circulation unaltered
distribution
rate and extent of movement of a drug into and out of tissues.
clearance
volume of blood or plasma cleared of drug per unit time
adverse drug reaction
unwanted or harmful reaction following administration of a drug or combination of rugs under normal condition of use and is suspected to be relation to the drug
side effect
an unintended effect of a drug related to its pharmacological properties and can induce unexpected benefits of treatment
physiochemical
reaction of drugs with each other
pharmacodynamics
the effect a drug has on the body
pharmacokinetics
what the body does to the drug
drug
a medicine or other substance that has a physiological effect when administered
pharmacology
branch of medicine concerned with uses, effects and modes of actions of drugs
drugability
the ability of a protein target to bind small molecules with high affinity
receptor
a component of a cell that interacts with a specific ligand and initiates a change of biochemical events- leading to the ligands observed effects
agonist
compound that binds to a receptor and activates it
antagonist
a compound that reduces the effect of the agonist
ligand
a molecule that binds to another molecule
full agonists
drugs that have full efficacy at the receptor
