BACKGROUND AND OBJECTIVES Due to the extensive use of antibiotics, the spread of drug-resistant bacteria is one of the most worrisome threats to public health. One strategy that can be used to overcome potential shortcomings might be the inactivation of these organisms by photodynamic therapy. In this study, we have investigated whether drug-resistant wound-associated organisms (Staphylococcus ...

Rabbit corneal endothelial cells demonstrated an increase of endothelial membrane permeability to inulin following perfusion with 5 X 10~ M rose bengal and exposure to 1050 /txW/cm incandescent light for either 1 min or 5 min when compared to corneas similarly perfused with rose bengal but not exposed to light. Endothelial permeability to dextran was unaltered following the photosensitization r...

Chlorpromazine and several other related phenothiazines are known to cause both phototoxic and photoallergic reactions in the skin and eyes of patients receiving these drugs. While the detailed mechanisms of photosensitization are not known, it is obvious that the first step must be the absorption of light by the drug, its metabolites, or photoproducts, or possibly an induced endogenous chemica...

Photosensitization is a novel environmentally friendly technology with promising applications in the food industry to extend shelf life. In this study, natural dye curcumin, when combined visible light (430 nm), was shown be an effective photosensitizer against common phytopathogenic fungi Botrytis cinerea (the cause of grey mould). Production associated phytotoxic metabolites botrydial and dih...

The aim of this work is to compare the antimicrobial efficiency of aminolevulinic acid-based photosensitization (ALA-photo) and chlorophyllin-based photosensitization (CHL-photo) against Gram-positive Listeria monocytogenes and Gram-negative Salmonella enterica, to assess some quantitative inactivation parameters of their survival curves and to propose a strategy for their effective inactivatio...

The response to Photofrin II-induced photosensitization on the activities of mitochondrial monoamine oxidase (MAO) and adenylate kinase (AK) were studied in order to gain further insight into site specific effects. Utilizing intact mitochondria in vitro, both MAO, located on the cytoplasmic side of the outer mitochondrial membrane, and AK, located in the intermembrane space, were inhibited by e...

Rabbit corneal endothelial cells demonstrated an increase of endothelial membrane permeability to inulin following perfusion with 5 X 10(-6) M rose bengal and exposure to 1050 muW/cm2 incandescent light for either 1 min or 5 min when compared to corneas similarly perfused with rose bengal but not exposed to light. Endothelial permeability to dextran was unaltered following the photosensitizatio...

In the present study, we analyzed DNA damage induced by phycocyanin (PHY) in the presence of visible light (VL) using a set of repair endonucleases purified from Escherichia coli. We demonstrated that the profile of DNA damage induced by PHY is clearly different from that induced by molecules that exert deleterious effects on DNA involving solely singlet oxygen as reactive species. Most of PHY-...

Photodynamic therapy (PDT) is an experimental cancer therapy inducing tumor tissue damage via photosensitizer-mediated oxidative cytotoxicity. A previous report indicates that oxidative stress induced by hydrogen peroxide or menadione activates the heat shock transcription factor in mouse cells but does not result in either increased transcription or translation of heat shock proteins (HSPs). O...

Results of the studies carried out on localization and photodynamic action of merocyanine 540 (MC540) on carcinoma of cervix (HeLa) cells are presented. Fluorescence microscopic study showed that when HeLa cells were incubated with MC540 in dark, the dye localized in plasma membrane of cells. Photoirradiation of cells in presence of MC540 led to enhancement of dye uptake, intracellular localiza...