In vitro photobiological evaluation of Rhodac, a new rhodacyanine photosensitizer.

We have previously shown that the rhodacyanine dye, Rhodac, exhibits a potent photocytotoxic activity in HeLa cells. In this study several aspects of the photobiological activity of Rhodac were further examined. Rhodac displayed no selective cytotoxicity toward several malignant cell lines after photosensitization (3.6 J/cm2), although HeLa cells were found to be the most sensitive. Interestingly, MCF-7/Adr cells, a multidrug-resistant subline, were less sensitive to the antiproliferative effect of photoactivated Rhodac. The subcellular localization, as revealed by confocal laser microscopy, demonstrated that the dye was mainly concentrated in the cytosolic membranes of the perinuclear region. The Rhodac-induced inhibition of HeLa cell proliferation after light exposure was found to be strictly oxygen dependent. In addition, photoactivated Rhodac induced poly(adenosine 5' diphosphate-ribose)polymerase cleavage, caspase-3 activation and apoptosis in HeLa cells. In the current work it was further demonstrated that Rhodac binds specifically to high-density lipoproteins and low-density lipoproteins, while no binding was observed to very low-density and heavy proteins. To sum up, our results show that Rhodac is an interesting and potent photosensitizer. Further in vivo experiments are required to elucidate whether the lipoprotein binding leads to a selective uptake of Rhodac in tumor cells and to address its efficacy in photodynamic therapy.

The relationship between nasal and middle ear pathology.

The results are presented of a prospective clinical-epidemiological study in 2069 healthy children 2 1/2-6 years of age, to determine the epidemiology of SOM and the role of some predisposing factors. Only the study of rhinological parameters is presented in this report. It was demonstrated that there is a very strong correlation between the annual incidence of common colds and of acute otitis media (p less than 0.0001). The correlation between common colds and the tympanometrical findings was not so high but still obvious (p less than 0.05), because of the higher number of negative middle ear pressures with increasing number of common colds. Open mouth breathing (p less than 0.01) and snoring (p less than 0.05) at night showed to be predisposing to SOM and in a lesser extent to negative middle ear pressure. The study of objective rhinoscopical parameters evaluating the condition of the nasal mucosa revealed that edema of the nasal mucosa (p less than 0.01) and the presence of pathological nasal secretions (p less than 0.05) are factors predisposing to SOM and to negative middle ear pressure. Even moderate septal deviations have an unfavourable influence on the eustachian tube function as was shown by the higher incidence of negative middle ear pressures in children with a moderate septal deviation compared to children with a straight septum (p less than 0.05).

[Lymecycline in the treatment of subacute sinusitis. Clinical study]. / Lymecycline in de behandeling van subakute sinusitis. Klinische studie.

After evaluation of the clinical efficacy and the tolerance of lymecycline 2 x 300 mg/day in patients with subacute sinusitis, we may conclude that lymecycline can be considered a first choice antibioticum in the treatment of acute and subacute sinusitis (Tetralysal).