The crystallization of calcium carbonate on porcine and human cardiac valves and the antimineralization effect of sodium alginate

Bacterially mediated mineralization of vaterite

“…Considering that bacteria have been related to human pathological calcification (Mc Lean et al, 1989), vaterite being found in human gallstones (Sutor and Wooley, 1968) and aortic valves (Kanakis et al, 2001), our results may help determine whether such vaterite pathological concretions are of bacterial origin, which is critical to the design of adequate medical treatments. However, a purely morphological (size and shape) analysis of such vaterite structures can not be used as an unambiguous biosignature since similar (spherulitic) morphologies are obtained by biotic and abiotic routes.…”

“…This is the case for abnormally calcified tissues, including regenerated damaged gastropod shells (Mayer and Weineck, 1932) and human pathological concretions such as gallstones (Sutor and Wooley, 1968;Bassi et al, 1994;Bogren et al, 1995;Palchik and Moroz, 2005), pancreatic stones and cloggings in human heart valves (Kanakis et al, 2001). Vaterite is sometimes found in hard tissues of some marine organisms (Lowenstam and Abbott, 1975), egg-shells of gastropods (Hall and Taylor, 1971) and birds (Dennis et al, 1996), vertebrate otoconia (Wright et al, 1982), crustacean statoliths (Ariani et al, 1993), and fish otoliths (David et al, 1994;Oliveira et al, 1996;Falini et al, 2005).…”

Inhibition of calcite growth by alginate

“…In particular, the inhibitory effect of sea water species such as magnesium and orthophosphate (Baker et al, 1980;Wilbur and Bernhardt, 1984;Morse et al, 2007) could explain the extremely slow recrystallization rates of chalk. Moreover, there is evidence that biopolymers produced by bacteria and algae, particularly the polysaccharides, significantly inhibit crystallization of calcium carbonate (Gunthorpe and Sikes, 1986;Welch et al, 1999;Kanakis et al, 2001;Manoli and Dalas, 2002;Butler et al, 2006).…”

Effects of initial supersaturation on spontaneous precipitation of calcium carbonate in the presence of charged poly-l-amino acids

“…It is supposed to be an important precursor in several calcium carbonate forming processes. Its natural occurrence is often associated with biogenic activities [1], as in pancreatic stones or clogging in human heart valves [28], hard tissues of fish otoliths [29], crustacean statoliths [30], ascidian skeleton [31], and fresh water pearls [32]. Although less common than the other polymorphs, vaterite and the studies of its initial nucleation, growth, and stabilization offer an opportunity to understand the mechanism of biomineralization and also the processes of crystal nucleation and growth in general [33].…”