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This study introduces a novel plasmonic nanocomposite platform, where gold nanoparticles (AuNPs) are synthesized in situ within a polydimethylsiloxane (PDMS) film. The innovative fabrication process leverages ethyl acetate swelling to achieve a uniform distribution of AuNPs, eliminating the need for additional reagents. The resulting nanocomposite film exhibits exceptional photothermal conversion capabilities, efficiently converting absorbed light into heat and rapidly reaching high temperatures. Furthermore, the platform is biofunctionalized with the phosphotriesterase enzyme, not only enabling the degradation of organophosphate pesticides but also showcasing the potential for multifunctional applications. The platform's ability to be regenerated after use underscores its sustainability for repeated applications.

Somatostatin is a peptide that plays a variety of roles such as neurotransmitter and endocrine regulator; its actions as a cell regulator in various tissues of the human body are represented mainly by inhibitory effects, and it shows potent activity despite its physiological low concentrations. Somatostatin binds to specific receptors, called somatostatin receptors (SSTRs), which have different tissue distributions and associated signaling pathways. The expression of SSTRs can be altered in various conditions, including tumors; therefore, they can be used as biomarkers for cancer cell susceptibility to certain pharmacological agents and can provide prognostic information regarding disease evolution. Moreover, based on the affinity of somatostatin analogs for the different types of SSTRs, the therapeutic range includes conditions such as tumors, acromegaly, post-prandial hypotension, hyperinsulinism, and many more. On the other hand, a number of somatostatin antagonists may prove useful in certain medical settings, based on their differential affinity for SSTRs. The aim of this review is to present in detail the principal characteristics of all five SSTRs and to provide an overview of the associated therapeutic potential in neoplasias.

The interaction between chiral drugs and biomimetic membranes is of interest in biophysical research and biotechnological applications. There is a belief that the membrane composition, particularly the presence of cholesterol, could play a pivotal role in determining enantiospecific effects of pharmaceuticals. Our study explores this topic focusing on the interaction of ibuprofen enantiomers (S- and R-IBP) with cholesterol-containing model membranes. The effects of S- and R-IBP at 20 mol% on bilayer mixtures of dipalmitoylphosphatidylcholine (DPPC) with 0, 10, 20 and 50 mol% cholesterol were investigated using circular dichroism and spin-label electron spin resonance. Morphological changes due to IBP enantiomers were studied with atomic force microscopy on supported cholesterol-containing DPPC monolayers. The results reveal that IBP isoforms significantly and equally interact with pure DPPC lipid assemblies. Cholesterol content, besides modifying the structure and the morphology of the membranes, triggers the drug enantioselectivity at 10 and 20 mol%, with the enantiomers differently adsorbing on membranes and perturbing them. The spectroscopic and the microscopic data indicate that IBP stereospecificity is markedly reduced at equimolar content of Chol mixed with DPPC. This study provides new insights into the role of cholesterol in modulating enantiospecific effects of IBP in lipid membranes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Curcumin, a plant polyphenol extracted from the Chinese herb turmeric, has gained widespread attention in recent years because of its multifunctional properties as antioxidant, antinflammatory, antimicrobial, and anticancer agent. Effects of the molecule on mitochondrial membranes properties have also been evidenced. In this work, the interaction of curcumin with models of mitochondrial membranes composed of dimyristoylphosphatidylcholine (DMPC) or mixtures of DMPC and 4 mol% tetramyristoylcardiolipin (TMCL) has been investigated by using biophysical techniques. Spectrophotometry and fluorescence allowed to determine the association constant and the binding energy of curcumin with pure DMPC and mixed DMPC/TMCL aqueous bilayers. The molecular organization of pure DMPC and cardiolipin-containing Langmuir monolayers at the air-water interface were investigated and the morphology of the monolayers transferred into mica substrates were characterized through atomic force microscopy (AFM). It is found that curcumin associates at the polar/apolar interface of the lipid bilayers and the binding is favored in the presence of cardiolipin. At 2 mol%, curcumin is well miscible with lipid monolayers, particularly with mixed DMPC/TMCL ones, where compact terraces formation characterized by a reduction of the surface roughness is observed in the AFM topographic images. At 10 mol%, curcumin perturbs the stability of DMPC monolayers and morphologically are evident terraces surrounded by cur aggregates. In the presence of TMCL, very few curcumin aggregates and larger compact terraces are observed. The overall results indicate that cardiolipin augments the incorporation of curcumin in model membranes highlighting the mutual interplay cardiolipin-curcumin in mitochondrial membranes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The behavior of lyotropic chromonic liquid crystals (LCLCs) in confined environments is an interesting research field that still awaits exploration, with multiple key variables to be uncovered and understood. Microfluidics is a highly versatile technique that allows us to confine LCLCs in micrometric spheres. As microscale networks offer distinct interplays between the surface effects, geometric confinement, and viscosity parameters, rich and unique interactions emerging at the LCLC-microfluidic channel interfaces are expected. Here, we report on the behavior of pure and chiral doped nematic Sunset Yellow (SSY) chromonic microdroplets produced through a microfluidic flow-focusing device. The continuous production of SSY microdroplets with controllable size gives the possibility to systematically study their topological textures as the function of their diameters. Indeed, doped SSY microdroplets produced via microfluidics, show topologies that are typical of common chiral thermotropic liquid crystals. Furthermore, few droplets exhibit a peculiar texture never observed for chiral chromonic liquid crystals. Finally, the achieved precise control of the produced LCLC microdroplets is a crucial step for technological applications in biosensing and anticounterfeiting.

Induced or spontaneous chirality in natural systems is an intriguing issue. In recent years, a lot of attention has been focused on chirality of chromonic liquid crystals, a class of materials that is able to self-assemble in columnar structures. However, the mechanism involved in the arising of chirality in these materials, that starts at the molecular level and controls the supramolecular structure, is poorly understood; however, it is certainly affected by ionic strength. In this work we present the results obtained doping Cromolyn, a chromonic material, with a strong helical-twisting-power peptide, and confining it in a spherical geometry. We demonstrate, by means of optical polarized microscopy and structural analysis, that both the geometrical constraint and the presence of the chiral dopant enhance the chiral effect; we also demonstrate that they favor the rise of a highly ordered helical superstructure, that may be optimized upon adding an ionic dye to the system. Finally, we report a procedure for the preparation of free-standing polymeric films, embedding and preserving the microspheres, and paving the way for the creation of biocompatible and eco-friendly optical devices to be used in the sensor and anticounterfeiting fields.

Mechano-bactericidal nanomaterials rely on their mechanical or physical interactions with bacteria and are promising antimicrobial strategies that overcome bacterial resistance. However, the real effect of mechanical versus chemical action on their activity is under debate. In this paper, we quantify the forces necessary to produce critical damage to the bacterial cell wall by performing simultaneous nanoindentation and fluorescence imaging of single bacterial cells. Our experimental setup allows puncturing the cell wall of an immobilized bacterium with the tip of an atomic force microscope (AFM) and following in real time the increase in the fluorescence signal from a cell membrane integrity marker. We correlate the forces exerted by the AFM tip with the fluorescence dynamics for tens of cells, and we find that forces above 20 nN are necessary to exert critical damage. Moreover, a similar experiment is performed in which bacterial viability is assessed through physiological activity, in order to gain a more complete view of the effect of mechanical forces on bacteria. Our results contribute to the quantitative understanding of the interaction between bacteria and nanomaterials.

A combination of time-resolved optical spectroscopy and nanoscale imaging has been used to study the complex binding to amyloids of a photocatalyst that selectively photo-oxygenates pathogenic aggregates, as well as the consequences of its irradiation. Correlative atomic force microscopy (AFM) and fluorescence microscopy reveals topography-dependent binding of the dye to model β-lactoglobulin fibers, which may also explain the observed difference in their response to photodegradation. We provide direct evidence of the photosensitization of singlet oxygen by the photocatalyst bound to amyloid fibers by direct detection of its NIR phosphorescence. The effect of singlet oxygen at the molecular level brings about nanoscale morphological changes that can be observed with AFM at the single-fiber level. We also find differential response of two α-synuclein mutants to photodamage, which can be rationalized by the presence of amino acids susceptible to photo-oxygenation. Overall, our results help to unravel some of the complexity associated with highly heterogeneous amyloid populations and contribute to the development of improved phototherapeutic strategies for amyloid-related disorders.

In this paper we report how the confining surfaces and the ionic effects of different concentration of guanosine solution can be used to vary the alignment of liquid crystal phases of guanosine nucleotides. Liquid crystal phases of guanosine 5'-monophosphate ammonium salt and guanosine 5'-monophosphate free acid in pure water, with and without silver sulphate, were studied by polarized optical microscope. A periodic modulation of the texture was observed. This modulation depends on both on the concentration and on the presence of silver ions in the liquid crystal phase. We demonstrate that, according to the surface energy of the alignment layers, it is possible to homeotropically align the guanosine chromonic phase without applying any external magnetic field. Finally, we report the formation of spherical, vesicle-like guanosine 5'-monophosphate aggregates, when the solution was confined between two hydrophobic surfaces containing exposed Si groups., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A two-fold active control of the plasmonic resonance of randomly distributed gold nanoparticles (GNPs) has been achieved. GNPs have been immobilized on an Indium Tin Oxide (ITO) coated glass substrate and then covered with a liquid crystalline compound. The system has been investigated by means of atomic force and scanning electron microscopy, revealing the presence of isolated and well distributed GNPs. The application of an external electric field to the sample has a two-fold consequence: the re-orientation of the hybrid-aligned liquid crystal layer and the formation of a carrier accumulation layer in the proximity of the ITO substrate. The refractive indices of both liquid crystal and accumulation layers are influenced by the applied field in a competitive way and produce a "dancing behavior" of the GNP's plasmonic resonance spectral position.

Geriatric and cancer-afflicted patients often experience decreased quality of life with cachexia, anemia, anorexia, and decreased activity level. We have studied the possibility that a myogenic plasmid that expresses growth hormone releasing hormone (GHRH) can prevent and/or treat these conditions. We administered plasmid to 17 geriatric and five cancer-afflicted companion dogs with an average age of 10.5+/-1.0 and 11.3+/-0.6 years at enrollment, respectively. Effects of the treatment were documented for at least 180 days post-treatment, with 10 animals followed for more than 1 year post-treatment, on average 444+/-40 days. Treated dogs showed increased IGF-I levels, and increases in scores for weight, activity level, exercise tolerance, and appetite. No adverse effects associated with the GHRH plasmid treatment were found. Most importantly, the overall assessment of the quality of life of the treated animals increased. Hematological parameters such as red blood cell count, hematocrit, and hemoglobin concentrations were improved and maintained within their normal ranges. We conclude that intramuscular injection of a GHRH-expressing plasmid is both safe and capable of improving the quality of life in animals for an extended period of time in the context of aging and disease. The observed anabolic and hematological responses to a single dose of this plasmid treatment may also be beneficial in geriatric patients or patients with cancer-associated anemia and/or cachexia.