NSG 530 Quiz 2 Study Guide. Wilkes University

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NSG 530 Quiz 2 Study Guide. Wilkes University.Endotoxins are released when the bacteria die/ the are produced by gram-negative bacteria. Endotoxins released by blood-borne bacteria cause the release ... of vasoactive enzymes that increase the permeability of blood vessels. Bacteria injure cells by producing exotoxins or endotoxins. Exotoxins are enzymes that can damage the plasma membranes of host cells or can inactivate enzymes critical to protein synthesis, and endotoxins activate the inflammatory response and produce fever. Gram-negative microbes produce an endotoxin (lipopolysaccharide [LPS]) that is a structural portion of the cell wall and is released during growth, lysis, or destruction of the bacteria or during treatment with antibiotics. Therefore, antibiotics cannot prevent the toxic effects of endotoxin. Bacteria that produce endotoxins are called pyrogenic bacteria because they activate the inflammatory process and produce fever. Septicemia is the proliferation of bacteria in the blood. Endotoxins released by bloodborne bacteria cause the release of vasoactive enzymes that increase the permeability of blood vessels. Leakage from vessels causes hypotension that can result in septic shock. Bacteremia occurs when bacteria are present in the blood. Gram-negative sepsis (sepsis or septicemia) occurs when bacteria are growing in the blood and release large amounts of endotoxin, when can cause endotoxic shock with up to 50% mortality. Released endotoxin, as well as other bacterial products, reacts with pattern recognition receptors (PRRs) and induces the overproduction of proinflammatory cytokines, particularly tumor necrosis factor-alpha (TNF-a), interleukin-1 (IL-1) and interleukin -6 (IL-6) which may secondarily be immunosuppressive. Endotoxin also is a potent activator of the complement and clotting system, leading to a degree of capillary permeability sufficient to permit escape of large volumes of plasma into surrounding tissue, contributing to hypotension and in severe cases, cardiovascular shock. Activation of the coagulation cascade leads to the syndrome of dissemination (or diffuse0 intravascular coagulation. Virulence: Capacity of a pathogen to cause severe disease (e.g., measles virus is a low virulence; rabies and Ebola viruses are highly virulent). https://www.youtube.com/watch?v=9G1OELPrivU Attenuated vaccines: alive, but less infectious. Live attenuated vaccines are created by weakening infectious organisms that can still replicate and induce protective immune responses without causing disease in the host. Vaccination with the live but attenuated organism generates an immune response that protects the vaccinated person against severe disease or even infection. Available since the 1950s, live attenuated vaccines (LAV) Live attenuated vaccines use live organisms that have been weakened so that they are avirulent, meaning they are unable to cause disease. Attenuation can be achieved in several ways:  Naturally occurring related organisms that are avirulent in humans, including host range restricted organisms or naturally occurring avirulent strains  Multiple rounds of growth of virulent organisms under conditions that weaken the organism such as in tissue culture or harsh physical conditions  Genetic manipulation of the organism to reduce virulence Understand different types of Immunity and associated labs- IgE, cell-mediated, autoimmunity vs alloimmunity Alloimmunity is the immune system’s reaction against antigens on the tissues of other members of the same species. Alloimmunity – Immune system of one individual produces an immunologic reaction against tissues of another individual. Alloimmune disorders include transient neonatal disease, in which the maternal immune system becomes sensitized against antigens expressed by the fetus; and transplant rejection and transfusion reactions, in which the immune system of the recipient of an organ transplant or blood transfusion reacts against foreign antigens on the donor’s cells. Alloimmunity can be observed during immunologic reactions against transfusions, transplants tissue, or the fetus during pregnancy. (Foreign Tissue body attacks) Whereas: Autoimmunity is a disturbance in the immunologic tolerance of self-antigens Autoimmune disease is loss of tolerance to self-antigens. There can be a genetic predisposition and the diseases can be a type II or type III hypersensitivity reaction. (Body attacks self) The inflammatory and immune responses are normally beneficial. They not only protect the body against microorganism invasion and cancer development, but they also stimulate tissue growth and repair after injury. However, when inflammation or immune responses are prolonged, excessive, or occur at an inappropriate time, normal tissues can be damaged instead of protected. These responses are considered "overreactions" to invaders and foreign antigens and are known as hypersensitivity or allergic responses. In addition, inflammatory and immune responses can fail to recognize self-cells and literally attack normal body tissues. This type of reaction is known as an autoimmune response. Both hypersensitivity and autoimmune responses can damage cells, tissues, or organs and have serious consequences. Hypersensitivity is an immune response misdirected against the host’s own tissues (autoimmunity) or directed against beneficial foreign tissues, such as transfusions or transplants (alloimmunity); or it can be exaggerated responses against environmental antigens (allergy). NEED TO figure this out and break it down mo [Show More]

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