Background And Aims: Mitral valve surgery and, more recently, mitral transcatheter edge-to-edge repair (TEER) are the two treatments of severe mitral regurgitation in eligible patients. Clinical comparison of both therapies remains limited by the number of patients analysed. The objective of this study was to analyse the outcomes of mitral TEER vs.
View Article and Find Full Text PDFBackground And Purpose: Epilepsy is associated with higher morbidity and mortality compared to people without epilepsy. We performed a retrospective cross-sectional and longitudinal cohort study to evaluate cardiovascular comorbidity and incident vascular events in people with epilepsy (PWE).
Methods: Data were extracted from the French Hospital National Database.
Background: Hypertensive encephalopathy (HE) constitutes a serious condition, usually observed in patients with long-lasting hypertension. Hypertension-associated HE is sometimes differentiated from the stroke-associated hypertensive emergency. Whether prognosis of hypertension-associated and stroke-associated HE is different is unclear.
View Article and Find Full Text PDFA study has been made of the fluorescence of poly d(G-m5C).poly d(G-m5C), a synthetic double-stranded DNA, in buffered neutral aqueous solution at room temperature, excited by synchrotron radiation at 280 nm and 250 nm and by a frequency-doubled pulse dye laser at 290 nm. Exciting at 280 nm, the B form shows a uni-modal UV spectrum with lambdaf(max) approximately 340 nm.
View Article and Find Full Text PDFThe effect of electron-accepting substituents in position 3 of the chlorine p6 macrocycle in neutral and carboxyl-containing negatively charged cycloimide derivatives of chlorin p6 (CIC) on the photochemical and biological properties of these photosensitizers was studied. A relationship between the structure and properties of CICs was analyzed on the basis of information on their photoinduced cytotoxicity, efficiency of the generation of reactive oxygen species, photostability, intracellular localization, quantitative parameters of accumulation in cells, and cellular pharmacokinetics. It was shown that these compounds can be used for the development of photosensitizers with intense light absorption at 740 nm, controlled intracellular localization, and a high photodynamic activity toward tumor cells.
View Article and Find Full Text PDFPhotosensitizers 13,15-[N-(3-hydroxypropyl)]cycloimide chlorin p6 (HPC) and 13,15-(N-methoxy)cycloimide chlorin p6 methyl ester (MMC) absorb at 711 nm and possess high photoinduced cytotoxicity in vitro. Here we report, that photodynamic therapy with HPC and MMC provide considerable antitumor effect in mice bearing subcutaneous P338 lymphoma. The highest antitumor effect was achieved at a dose of 4 micromol/kg when 1.
View Article and Find Full Text PDFLipophilic derivatives of chlorin p6, 13,15-N-(carboxymethyl)cycloimide methyl ester (CIC1) and 13,15-N-(2-carboxyethyl)cycloimide methyl ester (CIC2), were shown to absorb light in 710 nm region and to be efficient IR photosensitizers. They exhibit similar phototoxicities on the cells of A549 human lung adenocarcinoma, which are 40- and 100-fold higher than those of chlorin p6 and the clinically used Photogem, respectively, and are not toxic in the absence of light irradiation. The confocal spectral imaging technique allowed us to demonstrate that the high phototoxicity of CIC1 and CIC2 is due to their ability to readily penetrate to cells and to be bound to the cell membranes and lipid-containing structures in the monomeric photoactive form.
View Article and Find Full Text PDFMetal-free sulfonated phthalocyanine with the average number of sulfonate groups per molecule 2.4 (H(2)PcS(2.4)) was recently proved to be an efficient photosensitizer for the photodynamic therapy.
View Article and Find Full Text PDFComparative study of 13,15-[N-(2-hydroxyethyl)]cycloimide chlorin p6 (2), 13,15-(N-acetoxy)cycloimide chlorin p6 (3), 13,15-(N-hydroxy)cycloimide chlorin p6 methyl ester (4) and 13,15-(N-methoxy)cycloimide chlorin p6 methyl ester (5) together with the previously investigated 13,15-[N-(3-hydroxypropyl)]cycloimide chlorin p6 (1) was performed. The dependence of the key photodynamic properties of 1-5 on the introduced substituents was analyzed. The photoinduced cell-killing activity of 4 is 100- and 280-fold higher than that of chlorin p6 and Photogem, respectively, as estimated on A549 human lung adenocarcinoma cells.
View Article and Find Full Text PDFBackground: The weak efficiency of plasmid transfer into the cytosol remains one of the major limiting factors to achieve an efficient transfection with DNA/cationic polymer complexes. We found that divalent metal Zn2+ can improve the polyfection efficiency, especially with DNA/histidylated polylysine (His-pLK) complexes.
Methods And Results: The supplementation of the transfection medium with 250 micro M ZnCl2 increased the polyfection of human hepatocarcinoma (HepG2) cells with a plasmid encoding EGFP complexed with pLK, polyethyleneimine and His-pLK.
The 13,15-N-(3'-hydroxypropylcycloimide) chlorin p6 (CIC), which absorbs at 711 nm, possesses considerable photoinduced cell-killing activity. It is 43-, 61- and 110-fold more active than chlorin p6, 3-formyl-3-devinyl chlorin p6 and Photogem, respectively, and has no cytotoxicity without irradiation as estimated on A549 human adenocarcinoma cells. To attain the highest intracellular penetration and activity the monomeric form of CIC should be stabilized.
View Article and Find Full Text PDFIt is generally assumed that a central metal is essential for the efficiency of phthalocyanines in photodynamic therapy (PDT) of cancer. Contrary to the set opinion, the results of the present study indicate that the metal-free sulfonated phthalocyanines (H2PcSn, where n is the number of sulfonate groups per molecule) possess a considerable photoactivity. The relative phototoxicities of H2PcS1.
View Article and Find Full Text PDFThe fluorescence properties of thiazole orange, linked via a (1) hydrophobic alkyl or a (2) hydrophilic ethylene glycol chain to the central internucleotidic phosphate group of a pentadeca-2'-deoxyriboadenylate (dA15), are evaluated. Linkage at the phosphate group yields two stereoisomers, S-isomer of the phosphorus chiral center (Sp) and R-isomer of the phosphorus chiral center (Rp); these are studied separately. The character of the linkage chain and the chirality of the internucleotidic phosphate linkage site influence the fluorescent properties of these thiazole orange-oligonucleotide conjugates (TO-probes).
View Article and Find Full Text PDF"Light-up" probes, icosa-alpha-thymidylate-thiazole orange conjugates, for the in situ time-resolved detection of messenger ribonucleic acid (mRNA) in living cells are evaluated. Upon annealing with polyA in aqueous solutions, the icosa-alpha-thymidylate-thiazole orange conjugates were shown to be up to 15 times more fluorescent. Microinjection of these probes into adherent fibroblasts resulted in high yields of hybridization and fluorescent signals.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
September 2001
Fluorescein labeled carbohydrate (Glyc) probes were synthesized as analytical tools for the study of cellular lectins, i.e. SiaLe(x)-PAA-flu, Sia2-PAA-flu, GlcNAc2-PAA-flu, LacNAc-PAA-flu and a number of similar ones, with PAA a soluble polyacrylamide carrier.
View Article and Find Full Text PDFMolecular in vitro and in vivo properties of 3-devinyl-3-formylchlorin p6 (FCp6) were examined in order to characterize this derivative as a new prospective photosensitizer. The long-wavelength absorption maximum of FCp6 was 690-696 nm (depending on environment). FCp6 was found to bind readily to membranous structures and form complexes with some proteins.
View Article and Find Full Text PDFThe confocal spectral imaging (CSI) technique is described, its basic principles are considered, and a brief review of its applications to the study of biologically active compounds (BAC) within living cells and in tissue slices is presented. This technique is based on measurements and analysis of fluorescence or resonance Raman spectra in each point of the specimen under microscope with a three-dimensional resolution of about cubic micrometer. This technique is applicable to the study of stained fluorescent and nonfluorescent compounds.
View Article and Find Full Text PDFThe effect of interaction with DNA and oligonucleotides on the photophysical properties of two thiazole orange (TO) derivatives, with different side chains (-(CH2)3-N+(CH3)3 and -(CH2)6-I)) linked to the nitrogen of the quinoline ring of the thiazole orange, is presented here. The first one called TO-PRO1 is a commercially available dye, whereas the second one called TO-MET has been specially synthesized for further covalent binding to oligonucleotides with the aim of being used for specific in situ detection of biomolecular interactions. Both photophysical measurements and molecular calculations have been done to assess their possible mode of interaction with DNA.
View Article and Find Full Text PDFBinary systems combining a transition metal complex and ascorbate have been proposed recently for catalytic therapy of malignant tumors. The killing effect on tumor cells is achieved by production of free radicals in the course of accelerated oxidation of ascorbate by dioxygen in the presence of transition metal complexes. Further progress in the development of binary catalytic systems (BCSs) requires a special method for their investigation in cells and tissues, because neither component of BCSs fluoresces.
View Article and Find Full Text PDFWith the aim to perform spectroscopic studies and spectral images inside living cells, a microspectrofluorometer has been designed for two-dimensional spectral imaging in the visible and in the near-UV region. The main advantage of the device relies on its ability to scan the laser beam along one direction of the sample. This scanning is optically coupled with one direction of a bidimensional detector, allowing an instantaneous recording of a one-dimensional spectral image.
View Article and Find Full Text PDFWe have previously shown that when administered to mice without adjuvant, a chimeric peptide consisting of the fusion peptide F from measles virus protein linked at the C-terminus of a cytotoxic T-cell epitope from the M2 protein of respiratory syncytial virus efficiently primes for an major histocompatibility complex (MHC) class-I restricted cytotoxic T lymphocyte (CTL) response. In this report, we demonstrated by microspectrofluorometry that the fusion-peptide moiety bound to the plasma membrane of living cells. When the fusion peptide was linked to the C-terminus of the CTL epitope, the chimeric peptide (M2-F) adopted a marked beta-sheet conformation.
View Article and Find Full Text PDFThe incorporation of 10(-6) M ethidium bromide (EB) was studied in viable Drosophila melanogaster salivary glands with a spatial resolution reaching a few microns3, using a confocal laser microspectrofluorometer designed for spectral analysis. Spectra were recorded with the 514 nm Argon laser line during excitation times of 1 second (20 microW on the preparation) at 5 min intervals for 30 or 60 min, either at points in determined cell sites or serially throughout the cells. The fluorescence intensity time-course indicated that the EB intake was not an all-or-none process, but rather a graded, sensitive indicator of the functional state of the cell.
View Article and Find Full Text PDFPhotochem Photobiol
August 1996
The present report provides evidence that thymine dimerization can be UVA photosensitized at a tetranucleotide, 5'-TATT-3', by a 7-methyl-pyrido(3,4-c)psoralen monoadduct in DNA. The efficiency of the photoprocess depends on the tetranucleotide flanking sequences. These results demonstrate that one DNA lesion can originate the contiguous formation of a second type of lesion and emphasize the sequence-specific response to interaction of drugs with DNA.
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