pandemic
definitionA pandemic is…
The spread of an infectious disease across borders and continents.
papillomaviruses
definitionPapillomaviruses are…
Viruses, which infect the skin and mucous membranes and which can lead to development of tumours. While these may just be a benign wart, papillomaviruses are also known for causing cervical cancer.
parasite
definitionA parasite is…
Organism which lives at the expense of another, larger host organism. In most cases, the parasite harms but, as a rule, doesn’t kill the host. Examples of parasites include many species of worms and tics, but also the pathogens causing toxoplasmosis or malaria.
passive immunization
definitionPassive immunization means…
Emergency measure used in case of risk of a serious infection. Antibodies against the pathogen are injected into the body but the immune system does not make its own antibodies or memory cells. Vaccines can be administered intramuscularly (i.e. injected into a muscle) or subcutaneously (i.e. injected into the hypodermis) or they may be given orally.
pathogenic
Pathogenic means…
Causing disease.
Pathogenicity
definitionPathogenicity means…
Ability of a pathogenic species to cause disease by infection.
PCR
abbreviation ofpolymerase chain reaction
Method used to amplify DNA sequences in vitro. PCR exploits the properties of the enzyme DNA polymerase to synthesize a complementary strand of DNA from a template strand. Scientists can specify which segments the polymerase enzyme is to copy. The method is particularly useful when only small amounts of DNA are available. Popular tool used in diagnostics, molecular biology, forensics, and archaeology.
peptide
definitionA peptide is…
Short chain of amino acid building blocks.
plague
definitionPlague is…
Infectious disease caused by the bacterium Yersinia pestis, which, during the Middle Ages in Europe, claimed millions of lives. Today, the disease continues to pose a threat in some countries. The plague is an example of a zoonosis – the disease is transmitted from rat flea to human.
phagocytes
definitionPhagocytes are…
Scavenger cells of the defense system, which protect the body by ingesting bacteria, foreign particles, and dead cells and enzymatically breaking them down.
plasma membrane
definitionThe plasma membrane is…
Biological membrane which surrounds the living cell. It is made of a lipid bilayer and shields the cell from its environment.
plasma cells
definitionPlasma cells are…
Differentiated B cells that produce antibodies and release them to their environment.
plasmid
definitionA plasmid is…
Small circular piece of DNA which replicates independent of the genome. Plasmids are used in molecular biology as “gene ferries” that transport DNA.
polio
definitionPolio is…
Short for poliomyelitis, this disease of the nervous system caused by the polio virus may lead to paralysis. Children under the age of five are especially at risk. There is no treatment available, but a prophylactic oral vaccine does exist. Today, thanks to concerted global efforts, polio only still exists in three countries.
polyclonal antibodies
definitionPolyclonal antibodies are…
In contrast to monoclonal antibodies, polyclonal antibodies are made by many different B cells. They target the same antigen but recognize different regions of the antigen, in other words, different epitopes. They are obtained from the blood of animals that were vaccinated and are used in research as well as in passive immunizations.
polymerase chain reaction (PCR)
definitionPolymerase chain reaction (PCR) is…
Method used to amplify DNA sequences in vitro. PCR exploits the properties of the enzyme DNA polymerase to synthesize a complementary strand of DNA from a template strand. Scientists can specify which segments the polymerase enzyme is to copy. The method is particularly useful when only small amounts of DNA are available. Popular tool used in diagnostics, molecular biology, forensics, and archaeology.
prevalence
definitionPrevalence is…
A measure of the frequency of a disease at a given point in time. Prevalence is calculated by dividing the number with the disease by the number of people in the population.
primary infection
definitionA primary infection is…
First contact between a pathogen and the immune system.
prion
definitionA prion is…
Infectious abnormal variant of a protein which proliferates inside a host by forcing normal proteins of the same type to assume the abnormal form. Prion diseases include bovine spongiform encelphalopathy (BSE) in cows, scrapie in sheep, and Creutzfeldt-Jakob-disease in humans.
prokaryotes
definitionProkaryotes are…
Microorganisms whose genetic material is not enclosed by a nuclear membrane as it is in eukaryotes. Bacteria and archaea are examples of prokaryotes.
prophylaxis
definitionProphylaxis means…
Preventive measure against a disease, e.g. a vaccine.
protein
definitionA protein is…
Most important basic building block of a cell. Proteins are a class of macromolecules that give the cell its structure, interconvert chemical substances, receive signals, are messenger substances, or act as antibodies as part of the immune defense. Proteins are made up of amino acids that are arranged like pearls on a string. This string coils and folds upon itself until it gives rise to the shape the protein needs to be able to fulfil its function in the body. The information about the amino acid sequence in a protein is encoded by the corresponding gene.
proteome
definitionThe proteome is…
The totality of all proteins in a cell or organism at a given point in time. Because new proteins are constantly being made and old ones degraded, the proteome’s composition is constantly changing. Scientists conduct proteome research e.g. to better understand what happens in the body during an infection.
Pseudomonas
definitionPseudomonas is…
A genus of rod-shaped, Gram-negative bacteria with flagella. Found in nearly every type of environment. Pseudomonas include the species Pseudomonas aeruginosa, which causes disease in people with a weakened immune system.
Pseudomonas aeruginosa
definitionPseudomonas aeruginosa is…
See pseudomonas.