Abstract: The present invention is drawn to methods of killing bacteria, including antibiotic resistant bacteria, by contacting said bacteria with a membrane permeabilizing compound or combination of compounds and a membrane impermeant toxic agent or combination of agents, resulting in the death of the bacteria without substantial injury to the infected host or patient. The present invention is also drawn to compositions and kits for effecting the method of the present invention. The present invention is further drawn to methods of rendering toxic agents such as toxic organic molecules, membrane impermeant for use in the methods and compositions of the present invention.

Abstract: Method and apparatus for removing, from a flowing liquid stream containing a suspension of living cells, a subpopulation of unwanted cells having one or more characteristics distinguishing them from the rest of the living cells. The method includes detecting the presence of the unwanted cells, generating signals in response to the presence of the unwanted cells, and providing pulses of laser light, in response to the generated signals, to impinge on and kill the unwanted cells.

Abstract: Disclosed is a method ofbioassay based on the detection of changes in the membrane potential of individual cells. A cell suspension is incubated with a solution of a substance capable of affecting the physiology of at least a subpopulation of cells in the suspension. During or after the incubation, a measurement representative of the membrane potential of individual cells is made. Comparison of these measurements with reference measurements provides information concerning: (1) the viability of the cells or a subgroup thereof after exposure to toxic substances; (2) the presence and concentration of factors or ligands in the solution which bind specifically to cell membrane receptors; (3) the presence of cells in the suspension sensitive to factors known to be present in the solution; (4) the cumulative effect of plural factors in the solution on the cells or a subpopulation thereof; and (5) comparisons among the effects on the cells of plural, chemically distinct factors.

Abstract: A method and system for the non-invasive detection of zinc protoporphyrin (ZPP) in erythrocytes. Light at least partially within the fluorescence excitation spectrum of ZPP is directed onto the skin of a patient. The resultant incident light reflection and ZPP fluorescence from the region underlying the irradiated skin are detected. Signals representative of the detected light are generated and combined to provide a signal representative of the ZPP concentration in the erythrocytes within the sample region.