The chronic sensation of a dry mouth is a disease condition called xerostomia and affects a large part of the population. Xerostomia is associated with decreased secretion, or more often, qualitative changes in saliva proteins and immunoglobulin concentrations that develop as a result of salivary gland dysfunction. Several reasons causing dry mouth were described, and usually, they include taking medications, diseases or radiotherapy. In some situations, when it is difficult to use salivary stimulants or salivary gland damage is irreversible, the only option might seem to be saliva substitutes. The paper presents the most important aspects considering saliva preparations. The rheological and lubricating properties and the reconstruction of the complex saliva structure has been the main purpose of research. The biological properties of saliva preparations were also widely discussed. As part of the work, the antimicrobial effect of three commercial saliva preparations was tested. Finally, inadequate antimicrobial properties against the strains isolated from the oral cavity were demonstrated. The development of salivary substitutes, in particular, the improvement of antimicrobial properties, can be achieved using nanotechnology, including drug delivery systems containing nanocarriers.

Metallic biomaterials in the oral cavity are exposed to many factors such as saliva, bacterial microflora, food, temperature fluctuations, and mechanical forces. Extreme conditions present in the oral cavity affect biomaterial exploitation and significantly reduce its biofunctionality, limiting the time of exploitation stability. We mainly refer to friction, corrosion, and biocorrosion processes. Saliva plays an important role and is responsible for lubrication and biofilm formation as a transporter of nutrients for microorganisms. The presence of metallic elements in the oral cavity may lead to the formation of electro-galvanic cells and, as a result, may induce corrosion. Transitional microorganisms such as sulfate-reducing bacteria may also be present among the metabolic microflora in the oral cavity, which can induce biological corrosion. Microorganisms that form a biofilm locally change the conditions on the surface of biomaterials and contribute to the intensification of the biocorrosion processes. These processes may enhance allergy to metals, inflammation, or cancer development. On the other hand, the presence of saliva and biofilm may significantly reduce friction and wear on enamel as well as on biomaterials. This work summarizes data on the influence of saliva and oral biofilms on the destruction of metallic biomaterials.

Background Magnetic nanoparticles (MNPs) are characterized by unique physicochemical and biological properties that allow their employment as highly biocompatible drug carriers. Gelsolin (GSN) is a multifunctional actin-binding protein involved in cytoskeleton remodeling and free circulating actin sequestering. It was reported that a gelsolin derived phosphoinositide binding domain GSN 160–169, (PBP10 peptide) coupled with rhodamine B, exerts strong bactericidal activity. Results In this study, we synthesized a new antibacterial and antifungal nanosystem composed of MNPs and a PBP10 peptide attached to the surface. The physicochemical properties of these nanosystems were analyzed by spectroscopy, calorimetry, electron microscopy, and X-ray studies. Using luminescence based techniques and a standard killing assay against representative strains of Gram-positive ( Staphylococcus aureus MRSA Xen 30) and Gram-negative ( Pseudomonas aeruginosa Xen 5) bacteria and against fungal cells ( Candida spp.) we demonstrated that magnetic nanoparticles significantly enhance the effect of PBP10 peptides through a membrane-based mode of action, involving attachment and interaction with cell wall components, disruption of microbial membrane and increased uptake of peptide. Our results also indicate that treatment of both planktonic and biofilm forms of pathogens by PBP10-based nanosystems is more effective than therapy with either of these agents alone. Conclusions The results show that magnetic nanoparticles enhance the antimicrobial activity of the phosphoinositide-binding domain of gelsolin, modulate its mode of action and strengthen the idea of its employment for developing the new treatment methods of infections.

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Purpose: Efficient intracellular delivery of a therapeutic compound is an important feature of smart drug delivery systems (SDDS). Modification of a carrier structure with a cellpenetrating ligand, ie, cholesterol moiety, is a strategy to improve cellular uptake. Cholesterol end-capped poly(N-isopropylacrylamide)s offer a promising foundation for the design of efficient thermoresponsive drug delivery systems. Methods: A series of cholesterol end-capped poly(N-isopropylacrylamide)s (PNIPAAm) with number-average molar masses ranging from 3200 to 11000 g•mol-1 were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization from original xanthate-functionalized cholesterol and self-assembled into micelles. The physicochemical characteristics and cytotoxicity of cholesterol end-capped poly(N-isopropylacrylamide)s have been thoroughly investigated. Results: Phase transition temperature dependence on the molecular weight and hydrophilic/ hydrophobic ratio in the polymers were observed in water. Biological test results showed that the obtained materials, both in disordered and micellar form, are non-hemolytic, highly compatible with fibroblasts, and toxic to glioblastoma cells. It was found that the polymer termini dictates the mode of action of the system. Conclusion: The cholesteryl moiety acts as a cell-penetrating agent, which enables disruption of the plasma membrane and in effect leads to the restriction of the tumor growth. Cholesterol end-capped PNIPAAm showing in vitro anticancer efficacy can be developed not only as drug carriers but also as components of combined/synergistic therapy.

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Nanotherapy is a part of nanomedicine that involves nanoparticles as carriers to deliver drugs to target locations. This novel targeting approach has been found to resolve various problems, especially those associated with cancer treatment. In nanotherapy, the carrier plays a crucial role in handling many of the existing challenges, including drug protection before early-stage degradations of active substances, allowing them to reach targeted cells and overcome cell resistance mechanisms. The present review comprises the following sections: the first part presents the introduction of pharmacoeconomics as a branch of healthcare economics, the second part covers various beneficial aspects of the use of nanocarriers for in vitro, in vivo, and pre- and clinical studies, as well as discussion on drug resistance problem and present solutions to overcome it. In the third part, progress in drug manufacturing and optimization of the process of nanoparticle synthesis were discussed. Finally, pharmacokinetic and toxicological properties of nanoformulations due to up-to-date studies were summarized. In this review, the most recent developments in the field of nanotechnology’s economic impact, particularly beneficial applications in medicine were presented. Primarily focus on cancer treatment, but also discussion on other fields of application, which are strongly associated with cancer epidemiology and treatment, was made. In addition, the current limitations of nanomedicine and its huge potential to improve and develop the health care system were presented.

Plasma gelsolin (pGSN) is a highly conserved abundant circulating protein, characterized by diverse immunomodulatory activities including macrophage activation and the ability to neutralize pro-inflammatory molecules produced by the host and pathogen. Using a murine model of Gram-negative sepsis initiated by the peritoneal instillation of Pseudomonas aeruginosa Xen 5, we observed a decrease in the tissue uptake of IRDye®800CW 2-deoxyglucose, an indicator of inflammation, and a decrease in bacterial growth from ascitic fluid in mice treated with intravenous recombinant human plasma gelsolin (pGSN) compared to the control vehicle. Pretreatment of the murine macrophage line RAW264.7 with pGSN, followed by addition of Pseudomonas aeruginosa Xen 5, resulted in a dose-dependent increase in the proportion of macrophages with internalized bacteria. This increased uptake was less pronounced when cells were pretreated with pGSN and then centrifuged to remove unbound pGSN before addition of bacteria to macrophages. These observations suggest that recombinant plasma gelsolin can modulate the inflammatory response while at the same time augmenting host antibacterial activity.