Antifouling Activity of Halogenated Compounds Derived from the Red Alga Sphaerococcus coronopifolius: Potential for the Development of Environmentally Friendly Solutions

Nowadays, biofouling is responsible for enormous economic losses in the maritime sector, and its treatment with conventional antifouling paints is causing significant problems to the environment. Biomimetism and green chemistry approaches are very promising research strategies for the discovery of new antifouling compounds. This study focused on the red alga Sphaerococcus coronopifolius, which is known as a producer of bioactive secondary metabolites. Fifteen compounds, including bromosphaerol (1), were tested against key marine biofoulers (five marine bacteria and three microalgae) and two enzymes associated with the adhesion process in macroalgae and invertebrates. Each metabolite presented antifouling activity against at least one organism/enzyme. This investigation also revealed that two compounds, sphaerococcinol A (4) and 14R-hydroxy-13,14-dihydro-sphaerococcinol A (5), were the most potent compounds without toxicity towards oyster larvae used as non-target organisms. These compounds are of high potential as they are active towards key biofoulers and could be produced by a cultivable alga, a fact that is important from the green chemistry point of view.

Prospects for prevention of adhesion process during cardiac surgical interventions

The article is devoted to the problem of prevention of adhesions in cardiac surgery. It was determined that the problem is urgent due to the increase in the number of heart surgeries. The formation of adhesions is a reaction of the body after surgery, which is a stage of healing and partly performs a protective function. Nevertheless, the presence of adhesions violates the mechanical properties of the heart, negatively affects central hemodynamics, complicates the surgeon’s task during repeated surgical interventions and increases the risk of repeated operations.It has been shown that at present, for the prevention of adhesions, researchers tend to use biodegradable barrier materials with biocompatibility and the ability to dissolve after performing the barrier function. The main anti-adhesion agents used in cardiac surgery are membranes and gels. The requirements for an “ideal” agent for the prevention of adhesion were determined: biocompatibility, no irritating effect, no effect on wound healing, suppression of the growth of connective tissue in the pericardium.Conclusions. Until now, none of the funds has all the necessary qualities to prevent adhesion in the pericardium. Therefore, the search for effective methods for the prevention of postoperative adhesions remains relevant for cardiac surgery.

Fibronectin-Enriched Biomaterials, Biofunctionalization, and Proactivity: A Review

Modern innovation in reconstructive medicine implies the proposition of material-based strategies suitable for tissue repair and regeneration. The development of such systems necessitates the design of advanced materials and the control of their interactions with their surrounding cellular and molecular microenvironments. Biomaterials must actively engage cellular matter to direct and modulate biological responses at implant sites and beyond. Indeed, it is essential that a true dialogue exists between the implanted device and the cells. Biomaterial engineering implies the knowledge and control of cell fate considering the globality of the adhesion process, from initial cell attachment to differentiation. The extracellular matrix (ECM) represents a complex microenvironment able to meet these essential needs to establish a relationship between the material and the contacting cells. The ECM exhibits specific physical, chemical, and biochemical characteristics. Considering the complexity, heterogeneity, and versatility of ECM actors, fibronectin (Fn) has emerged among the ECM protagonists as the most pertinent representative key actor. The following review focuses on and synthesizes the research supporting the potential to use Fn in biomaterial functionalization to mimic the ECM and enhance cell–material interactions.

BIOMATERIALS BASED ON CHITOSAN AND ITS DERIVATIVES TO PREVENT ADHESION FORMATION

An increase in the number and volume of surgical interventions leads to an increase in the frequency of postoperative adhesions. The development of the adhesion process in the abdominal cavity causes pain, a decrease in the quality of life of patients, a violation of the reproductive function of women as well as acute adhesion intestinal obstruction. Recently, polymer biomaterials, including those based on chitosan, have been widely used for the prevention of adhesions. Due to their biocompatibility and biodegradation ability, they do not require repeated operations to extract the material. It is believed that these materials act as barriers, physically separating the damaged surfaces. The molecular mechanism of their action is still poorly understood. In this review, the main mechanisms of adhesion formation, as well as ways to prevent them with the help of materials based on chitosan and its derivatives, are discussed.

Immunocompetent cells in the tissue of adhesives of patients with adhesion process in the small pelvis

Objective: To study the morphological features and subpopulation composition of immunocompetent cells of adhesion tissue in women with adhesions of the pelvic organs.Materials and Methods: Th e study was carried out using surgical material obtained from 70 women aged 23 to 40 years. Of these, 50 tissue samples of peritoneal adhesions from patients with adhesions of organs in the small pelvis of I – II degree who underwent adhesiolysis and 20 samples of parietal peritoneum from healthy women who underwent endoscopic sterilization for contraception or completion of generative function. Th e authors used histological, immunohistochemical, and morphometric research methods.Results: Immunological changes in adhesion tissue were characterized by the activation of the T-cell link of immunity. It was confi rmed by a signifi cant increase in the content of CD4+ (p <0.001), CD8+ (p <0.001), a shift in the balance of immunoregulatory subpopulations towards CD8+, a lower indicator of the immunoregulatory index (p = 0.015), and insuffi ciency of the humoral link of immunity, namely, the absence of CD20+ content against the background of a slight increase in the CD138+ pool.Conclusion: To prevent the postoperative adhesion process in the small pelvis in patients of reproductive age, it is necessary to apply immunomodulatory therapy in the early postoperative period, which will improve the results of surgical treatment and is pathogenetically justifi ed.

Biomimetic scaffolds based on chitosan in bone regeneration. A review.

The article focuses on a polysaccharide of natural origin – chitosan and its application in tissue engineering. The preparation process and physicochemical properties of the saccharide are described. The degradation of chitosan and the properties influencing the process both outside and in living organism were examined. Four applications in bone tissue engineering can be distinguished: preparation of cell scaffolds exclusively from chitosan, from a chitosan composite or from a chitosan polyelectrolyte complex. The fourth way is to modify the surface of scaffolds made of other materials by covering them with a layer of chitosan. At the end of the article, the processes taking place after placing the implant inside the body are described, how the structure of chitosan affects the behaviour of bone cells in the adhesion process and life processes.

A Novel Leptospira interrogans Protein LIC13086 Inhibits Fibrin Clot Formation and Interacts With Host Components

Leptospirosis is a neglected zoonosis, caused by pathogenic spirochetes bacteria of the genus Leptospira. The molecular mechanisms of leptospirosis infection are complex, and it is becoming clear that leptospires express several functionally redundant proteins to invade, disseminate, and escape the host’s immune response. Here, we describe a novel leptospiral protein encoded by the gene LIC13086 as an outer membrane protein. The recombinant protein LIC13086 can interact with the extracellular matrix component laminin and bind plasminogen, thus possibly participating during the adhesion process and dissemination. Also, by interacting with fibrinogen and plasma fibronectin, the protein LIC13086 probably has an inhibitory effect in the fibrin clot formation during the infection process. The newly characterized protein can also bind molecules of the complement system and the regulator C4BP and, thus, might have a role in the evasion mechanism of Leptospira. Taken together, our results suggest that the protein LIC13086 may have a multifunctional role in leptospiral pathogenesis, participating in host invasion, dissemination, and immune evasion processes.