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Aim: Develop conditions for inactivation of staphylococcus by using photosensibilizator merocyanine 540 (MC540) for the production of antigenic preparation (AP). Study some of immune reactions to AP and the possibility of regulation of DTH reaction to AP under the effect of MC540., Materials and Methods: Merocyanine 540 (MC540, Sigma-Aldrich, Switzerland) is used in the study. MC540 and Staphylococcus aureus, strain 78 (Sa78) were irradiated by light of a mercury-quartz lamp DRSH-250 (Zelenograd). C56BL/6 line mice were immunized once by subcutaneous administration of AP. DTH reaction was tested 7 days after the immunization. Functional activity of peritoneal exudate macrophages was determined 1 and 9 days after the immunization. Immune modulating effect of MC540 in DTH was determined after its per os administration to mice 1 hour after AP sensibilization., Results: In order to obtain AP, S. aureus suspension at the concentration of 2.5 x 10(7) CFU/ml in 25 microM MC540 solution and 0.25 M NaCl solution were exposed to irradiation for 5 minutes. During DTH reaction induction its intensity dependence on AP dose was revealed. A persistent increase of a lysosomatic enzyme cathepsin D in macrophages of peritoneal exudate after a single administration of AP was noted. During MC540 irradiation an accumulation of photoproducts that have a pronounced immune suppression effect in DTH reaction had a dose-dependent character., Conclusion: Use of saline allows to increase bactericidal potential of a photosensibilizator (PS). However during therapy of localized forms of infection a possible immune modulating effect of PS on macro organism should be considered. By varying PS dose and irradiation time not only maximum bactericidal effect can be achieved but also regulation of inflammatory reactions in the area of PS effect can be ensured.

We used the phenomenon of previously described photoinduced fluorescence quenching and fluorescence polarization to evaluate the transfer of meta-tetra(hydroxyphenyl)chlorin (m-THPC) from commercial high-drug load liposomes to plasma proteins and model membranes. Fluorescence quenching of m-THPC in liposomes by iodide indicates that part of m-THPC in PEGylated liposomes is localized in the PEG shell, while the rest is bound to the lipid bilayer. It was shown that the two molecule pools in the commercial PEGylated liposomal formulation Fospeg® condition the characteristics of the m-THPC release kinetics. A substantial percentage of m-THPC from Fospeg® is released much faster than from the conventional liposomal formulation Foslip®. Using the technique of resonance light scattering, it was shown that partial m-THPC aggregation is present in liposomes with very high drug loads, higher in PEGylated liposomes compared to conventional ones.

Resonance light scattering, a phenomenon of an abrupt enhancement of Rayleigh light scattering in close proximity to an absorption band, is easily detectable in solutions of strongly absorbing chromophores, which form large aggregates with strong pi-pi-electronic coupling among the chromophores. Resonance light scattering spectra need to be corrected for the sensitivity of spectrofluorimeter as well as for the effects of internal light filter. A method for correcting the measured resonance light scattering is described. It was shown by the method that the addition of KCl induces the formation of extended supramolecular aggregates (probably of H-type) of the anionic dye merocyanine 540 in water. The spectra of the resonance light scattering of the photosensitizer meta-tetra(hydroxyphenyl)chlorin (mTHPC, foscan ) indicate the formation of J-aggregates of this dye in aqueous medium.

The sarcoplasmic reticulum (SR) is present as an extensive network in uterine cells. In this chapter we examine its functional importance, relating in particular, to the control of contractility in pregnancy. The uterine SR has both ryanodine receptors (RyR) and inositol-1 ,4,5-trisphosphate InsP3 receptors (InsP3R). The RyR and subsequent Ca24-induced Ca2+ release play little role in either human or rat contractions or Ca2+ transients. There may be subtle, spatiotemporal effects at the single cell level. Caffeine, an agonist for RyR fails to release Ca2+ and indeed produces relaxation not contraction. InsP3 dearly causes release of Ca2+ from the uterine SR and an increase in force, although these changes are only small and transient compared to those occurring due to external Ca2+ entry. Inhibition of the SR Ca-ATPase by cyclopiazonic acid, empties Ca2+ from the SR. This is associated with an augmentation of force and Ca2+ transient. Thus the SR normally functions in the uterus to limit, not increase contractions. The mechanism may involve vectoral release of Ca2+ from the SR and activation of surface membrane K+ channels. This activation would tend to decrease L-type Ca2+ entry and hence reduce contraction. Thus the SR is playing a role in controlling membrane excitability and hence contractility. The SR also plays a role in the relaxation of force. This is not primarily due to a direct sequestering of large amounts of Ca2+, but rather that the SR directs Ca2+ to the surface membrane extrusion mechanisms, i.e. Ca-ATPase and Na+/Ca2+ exchanger. This enables them to act more efficiently, and therefore aids relaxation. Recent direct measurements of SR luminal content show decreases with agonist application but not during spontaneous activity; confirming the results described above. This technique will be used to better characterize the uterine SR, its control and relevance to normal and abnormal labours.