Bacterial killing

Bacterial kill is independent of the intensity of the light but depends on the total dose. 

IgG Main antibody in the secondary response. Opsonizes bacteria, making them easier to phagocytose. Fixes complement, which enhances bacterial killing. Neutralizes bacterial toxins and viruses. Crosses the placenta. 

Decreased rate of bacterial killing in lungs in vivo... 

Aminoglycosides are most useful for bacteraemias (especially Gram-negative septicaemia) since their volume of distribution is relatively low. With the exception of patients with renal failure or endocarditis they should be administered once-daily. This is because they exhibit a dose-dependent pharmacodynamic effect. This means that bactericidal activity is determined more by the peak plasma concentration than by the time that the plasma concentration is above the minimum required to achieve bacterial killing. The converse is true of p-lactams, which exhibit t/me-cfepenofent bacterial killing. 

Whole cell, killed bacterial vaccines previously given to humans were generally of limited immunogenicity. While many of the adverse reactions with these preparations were described as acceptable, the frequency of systemic reactions (25%) in healthy individuals might give one pause before using them in larger patient populations. Several studies have administered whole bacterial, killed... 

The relative importance of the contribution of superoxide/hydrogen peroxide and hypochlorous acid in the bacterial killing mechanism is seen in patients with chronic granulomatous disease (CGD, with a defective NADPH-oxidase system), and those that are myeloperoxidase-deficient. CGD patients show persistent multiple infections especially in the skin, lungs, liver and bones by those bacterial strains whose killing by neutrophils requires oxygen. Individuals who are deficient in myeloperoxidase show no symptoms. 

Hampton, M.B., Kettle, A.J. and Winterboum C.C., Inside the neutrophil phagosome oxidants, myeloperoxidase and bacterial killing. Blood, 92, 3007, 1998. 

Wentworth P Jr, McDunn JE, Wentworth AD, Takeuchi C, Nieva J, Jones T, Bautista C, Ruedi JM, Gutierrez A, Janda KD, Babior BM, Eschenmoser A, Lerner RA. Evidence for antibody-catalyzed ozone formation in bacterial killing and inflammation. Science 2002 298(5601) 2195-2199. 

Mode of action is that of the p-lactams, i.e. cephalosporins impair bacterial cell wall s)mthesis and hence are bactericidal. They exhibit time-dependent bacterial killing (see p. 203). 

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