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Bone regeneration after injury or after surgical bone removal due to disease is a serious medical challenge. A variety of materials are being tested to replace a missing bone or tooth. Regeneration requires cells capable of proliferation and differentiation in bone tissue. Although there are many possible human cell types available for use as a model for each phase of this process, no cell type is ideal for each phase. Osteosarcoma cells are preferred for initial adhesion assays due to their easy cultivation and fast proliferation, but they are not suitable for subsequent differentiation testing due to their cancer origin and genetic differences from normal bone tissue. Mesenchymal stem cells are more suitable for biocompatibility testing, because they mimic natural conditions in healthy bone, but they proliferate more slowly, soon undergo senescence, and some subpopulations may exhibit weak osteodifferentiation. Primary human osteoblasts provide relevant results in evaluating the effect of biomaterials on cellular activity; however, their resources are limited for the same reasons, like for mesenchymal stem cells. This review article provides an overview of cell models for biocompatibility testing of materials used in bone tissue research. [ABSTRACT FROM AUTHOR] more...

Diseases are important drivers of population and ecosystem dynamics. This review synthesizes the effects of infectious diseases on the population dynamics of nine species of marine organisms in the Chesapeake Bay. Diseases generally caused increases in mortality and decreases in growth and reproduction. Effects of diseases on eastern oyster (Crassostrea virginica) appear to be low in the 2000s compared to effects in the 1980s–1990s. However, the effects of disease were not well monitored for most of the diseases in marine organisms of the Chesapeake Bay, and few studies considered effects on growth and reproduction. Climate change and other anthropogenic effects are expected to alter host-pathogen dynamics, with diseases of some species expected to worsen under predicted future conditions (e.g., increased temperature). Additional study of disease prevalence, drivers of disease, and effects on population dynamics could improve fisheries management and forecasting of climate change effects on marine organisms in the Chesapeake Bay. [ABSTRACT FROM AUTHOR] more...

As the problem of bacterial contamination continues to grow in its significance, researchers have reported many antibacterial materials that are based on inorganic compounds. Of these, materials that are based on silica and its derivatives have been widely used in engineering, medicine, and food. This paper reviews the advantages, safety issues, and applications of silica and its derivatives, as reported in recent years. The information provided highlights the preparation, application, and antimicrobial efficiency of materials that are based on silica and have different structure/size. We outline the possible antimicrobial mechanisms of silica‐based materials and the potential challenges that researchers may face. With a focus on increasing concerns regarding bacterial contamination in the food and medical industries, we have also proposed corresponding antibacterial material preparation strategies. [ABSTRACT FROM AUTHOR] more...

Tamm-Horsfall glycoprotein (THGP), produced exclusively by renal cells from the thick ascending limb of Henle's loop, is attached by a glycosyl-phosphatidylinositol (GPI)-anchor to the luminal face of the cells. Urinary excretion of THGP (50–100 mg/day) occurs upon proteolytic cleavage of the large ectodomain of the GPI-anchored form. N-Glycans, consisting of a large repertoire of sialylated polyantennary chains and high-mannose structures, account for approximately 30% of the weight of human urinary THGP. We describe: (i) the involvement of urinary THGP high-mannose glycans in defense against infections of the urinary tract, caused by type-1 fimbriated Escherichia coli, which recognize high-mannose structures, (ii) the role of GalNAcβ1-4(NeuAcα2-3)Galβ1-4GlcNAcβ1-3Gal (Sda determinant) carried by human THGP in protecting the distal nephron from colonization of type-S fimbriated E. coli which recognise NeuAcα2-3Gal, (iii) the inhibitory effect of sialylated THGP on crystal aggregation of calcium oxalate and calcium phosphate, thus preventing nephrolithiasis. Finally, we outline the importance of N-glycans in promoting the polymerization of THGP, a process resulting in the formation of homopolymers with an M r of several million in urine. Since THGP defense against diseases of the urinary tract mainly consists in binding damaging agents, its ability to behave as a multivalent ligand significantly enhances this protective role. [ABSTRACT FROM AUTHOR] more...