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Pathophysiology
Pathophysiology of infectious diseases - Q/A
Question | Answer |
---|---|
Bacteria's capacity to cause disease is a function of what? | Virulence |
A change in what can lead to expression of disease? | Either microbial factors and defenses of the host |
What factors determine virulence? | Those that allow the organism to colonize, proliferate, invade, or otherwise modify hose tissues and organs |
Is the source always the same as the reservoir? | No |
The virulence of Neisseria gonorrhoeae and many enteric or urinary pathogens is highly dependent on? | Pili |
Why are pili so important in the virulence of Neisseria gonorrhoeae virulence? | They promote adherence in the face of opposing urinary or fecal flow |
What is the first barrier to invading microbes? | Integrity of the epidermis and mucosal epithelium |
What is the principal structural component of the cell wall? | Peptidoglycan |
Where is peptidoglycan located? | Just external to the cytoplasmic membrane |
What kind of cell wall do Gram (-) bacteria have? | Thin peptidoglycan layer linked by lipoproteins to a phospho-lipid-lipopolysaccharide bilayer outer membrane |
What kind of cell wall do Gram (+) bacteria have? | Relatively thick peptidoglycan layer interspersed with teichoic or lipoteichoic acids and coated with surface proteins |
What does the phospho-lipid-lipopolysaccharide bilayer outer membrane of gram (-) bacteria contain? | Surface proteins as well as integral proteins, some of which act as receptors, porins, and active transporters |
What are the gram stain results of Gram (+) bacteria? | Retain the crystal violet-iodine complex |
What are the gram stain results of Gram (-) bacteria? | Retain only the red saffranin coutnerstain |
What is the primary goal of a bacterium? | To replicate (i.e., make more bacteria) |
What type of bacteria tend to be associated with severe disease? | When they infect humans, bacteria that are better adapted to animals than they are to humans |
What are pili composed of? | One or more major structural subunits and often possess a tip protein (or proteins) that directly mediate binding to a host receptor |
What are bacterial attachment factors? | Adhesins |
What provides a means for communication between pathogen and host and between pathogens? | Adherence |
Why do many bacterial pathogens usually express multiple adhesins, sometimes with overlapping function? | Because adherence is so critical |
What are pili? | Macromolecular hairlike appendages that are one of the most prominent types of bacterial adhesins |
What are some routes of horizontal transmission? | Contact, common vehicle, airborne, vectorborne |
What are the basic strategies for controlling and preventing the further transmission of infectious diseases? | 1) Treating the source of the infection and/or eliminating the source from the environment 2) Isolation 3) Preventing subsequent transmission through behavior modification or other interventions 4) Protecting the persons at risk |
What are the six factors that contribute to the emergence of infectious diseases identified by the IOM committee? | 1) Changes in demographics and behavior 2) Advances in tech and industry 3) Economic dev and changes in land use 4) Increases in travel and commerce 5) Microbial adaptation 6) Deterioration of the PH system bc of financial and human resource constraints |
How long has gonorrhea been on the national notifiable disease list? | Since 1944 |