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The mono- and the digalactosyldiacylglycerol (MGDG and DGDG) galactolipids with a high content of polyunsaturated fatty acids, mainly omega-3, have been purified from the thermophilic blue-green alga ETS-05 that colonises the therapeutic thermal mud of Abano and Montegrotto, Italy. The therapeutic thermal mud is applied mostly to osteoarthritic cartilage patients. In the present study, a possible anti-inflammatory function of MGDG in cartilage has been studied in the avian articular cartilage model. We report that, in response to an inflammatory stimulus, adult avian articular cartilage cells express inflammation-related proteins, such as the lipocalin extracellular fatty acid binding protein, Avidin and Serum Amyloid A. The treatment of avian articular chondrocytes with the galactolipid MGDG suppressed the expression of the inflammation-induced proteins, suggesting a strong anti-inflammatory property of MGDG. MGDG has, in addition, a cell anti-proliferative activity, but it does not interfere with cell differentiation, suggesting a protective role for articular cartilage.

Single-wall carbon nanohorns (SWNHs) are a new class of material that is closely related to single-wall carbon nanotubes. Here, we describe the synthesis and characterization of a series of SWNHs functionalized with ethylene glycol chains and porphyrins. Functionalization of carbon nanohorns has been achieved using two different synthetic protocols: (1) direct attack of a free amino group on the nanohorn sidewalls (nucleophilic addition) and (2) amidation reaction of the carboxylic functions in oxidized nanohorns. The nanohorn derivatives have been characterized by a combination of several techniques, and the electronic properties of the porphyrin/nanohorn assemblies (SWNH/H2P) have been investigated by electrochemistry, spectroelectrochemistry, and a series of steady-state and time-resolved spectroscopy. The cyclic voltammetry curve of nanohorn/porphyrin conjugate 6 showed a continuum of faradic and pseudocapacitive behavior, which is associated with multiple-electron transfers to and from the SWNHs. Superimposed on such a pseudocapacitive current, the curve also displays three discrete reduction peaks at -2.26, -2.57, and -2.84 V and an oxidation peak at 1.12 V (all attributed to the porphyrin moiety). Steady-state and time-resolved fluorescence demonstrated a quenching of the fluorescence of the porphyrin in SWNH/H2P conjugates 5 and 6 compared to the reference free base porphyrin. Transient absorption spectra permitted the electron-transfer process between the porphyrins and the carbon nanostructures to be highlighted.