Carrageenan, a polysaccharide derived from red seaweeds, is commonly used to induce inflammation in animal models for studying inflammatory diseases. Its pro-inflammatory effects involve several key mechanisms: Activation of the Immune System: Carrageenan stimulates local immune cells, particularly macrophages, leading to an increased release of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Disruption of Epithelial Barrier: It causes damage to the intestinal epithelial barrier, increasing intestinal permeability and facilitating the entry of pathogens and toxins, which exacerbates inflammation. Production of Inflammatory Mediators: Carrageenan enhances the production of inflammatory mediators like prostaglandins and leukotrienes, contributing to inflammation and pain. Modulation of Signaling Pathways: It affects important signaling pathways, including NF-κB and MAPK, which are crucial in regulating the inflammatory response. These mechanisms make carrageenan a valuable tool for studying inflammatory processes and evaluating the efficacy of anti-inflammatory treatments in animal models.

Natural zeolites are ‘functional minerals’ with countless technological capabilities in catalysis, cation-exchange, sieving, etc. So far the zeolite industrial exploitation has been mostly based on their microporosity (e.g., molecular traps, aroma release, desiccants). Such unique porosity type follows to a zeolite crystal lattice made of regular arrays of interconnected nanometric channels. However, zeolites have further peculiarities like a crystalline structure having hybrid ionic-covalent nature. The presence of substitutional point defects (i.e., tetravalent aluminum atoms distributed within the porous crystalline silica lattice) causes the presence of nucleophilic sites in this covalent silico-alluminate framework, electrically balanced by extra-framework cations. Such unique feature provides the zeolite crystal of electrical conductivity based on an ionic transport mechanism. However, single charge-carrier ionic conduction by hopping takes place only in the case cations are bonded to molecules (e.g., H2O, O2, N2, etc.) through ion-dipole electrostatic interactions. The nonspecific nature of this electrical response makes zeolites potentially useful in fabricating vacuum sensors for airspace applications and in general pressure sensors. Cation size and concentration (atomic Si/Al ratio) are determining factors for the performance of these devices (electrical conductivity depends on charge carrier mobility and density). Clinoptilolite is a high purity natural zeolite with chemical and mechanical characteristics very adequate for these sensing applications. Recently, overviews on clinoptilolite uses as electric sensor have appeared in literature.

All solids contain ‘dangling bonds’, whose percentage increases with size decreasing. According to surface/volume ratios, such an increase is for 0-D and 1-D nanostructures much faster than for 2-D nanostructures (proportion is 6:4:2 for 0-D, 1-D and 2-D nanostructures, respectively). Such an excessive unsaturation of atomic valences in 0-D and 1-D nanostructures does not allow their existence in nature. Differently, 2-D nanostructures for their lower dangling bond content are frequently found in nature.

(A) The initiation of cell death through various pathways is contingent upon the location of the photosensitizer (PS) and the degree of organelle damage. Photodynamic therapy (PDT)-induced damage to mitochondria results in the loss of membrane permeability and the release of pro-apoptotic factors. Conversely, damage to the endoplasmic reticulum (ER) leads to the release of stored cellular calcium deposits. Furthermore, lysosomal damage results in the release of proteolytic enzymes upon illumination and can also trigger autophagy. In instances where apoptosis is impaired, necrosis and autophagy may emerge as the primary mechanisms of cell death following PDT. It is noteworthy that multiple PSs may localize in different organelles, potentially leading to the concurrent activation of multiple cell death pathways (adapted from Mroz, P et al. [1]). (B)  Photodynamic therapy has the capacity to induce vascular damage, disrupting the tumor's blood supply and causing its demise through various mechanisms. (C)  Photodynamic therapy can also activate innate and adaptive immunity, eliciting a systemic antitumor immune response and ultimately eradicating tumor cells.

Colored polymers are quite a rarity; indeed, there are a few families of linear polymers showing coloration usually ranging from pale-yellow to dark brown (most polymers are amber colored). These polymers belong to the high performance thermoplastics class (e.g., polyarylsulfones, polyimides, polyamideimides, etc.). The visible coloration is frequently associated with a high optical transparency (i.e., absence of light-scattering phenomena), which occurs for the amorphous nature of these solids. These solids are characterized by a sharp transparency change at a special wavelength, named cut-off. Precisely, they are very transparent at wavelengths higher than the cut-off wavelength and completely opaque at wavelengths below the cut-off wavelength. Since optical absorption of inherently colored polymers extends up to the visible spectral region, these solids are capable to completely absorb ultraviolet photons (that is, UV-C sub-band, like most of plastics do, but also the UV-B and UV-A sub-bands). The absorption coefficient of these polymers is very high and, consequently, they can completely block the ultraviolet radiation unless they are processed in form of thin films or coatings. It must be pointed out that common dyed plastics are obtained by dissolving an organic colorant into a plastic material and consequently the resulting optical absorption comes from the chromophores present in this organic molecule. Intrinsic/inherent coloration has a completely different nature, it is due to a huge bell-shaped absorption band, extending over a wide spectral range, which is generated by photoexcitation of electrons contained in the valence band states to the empty conduction band states. These inherently colored polymeric optical media constitute a niche class of polymeric materials potentially useful in the optical fields for technological applications like optical limiters, UV-shielding optical windows, color filters, etc.