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3.7 Pathological Biomineralization in Marine Vertebrates
Abstract The formation of crystalline structures in pathological mineralization
follows the same principles as normal biomineralization. The mechanism of formation of various stones in organisms of marine vertebrates remains unclear. Stones
consist of several kinds of minerals like struvite, calcium carbonate and phosphate;
either alone or in combination. Different types of calculi (dental, nasal, renal, vaginal,
cystic) as well as stones (uroliths, nephroliths, enteroliths, faecoliths) observed in
fi sh, reptilians and marine mammals are described and discussed in this chapter.
According to the classical defi nition proposed by Catherine Skinner “Biominerals
may be deposited within the organism, and within its immediate surroundings or
environment, as a result of the metabolism of the living creature, ” (Ehrlich et al.
2008 ; see for more information Skinner 2000 ). Biominerals of the vertebrates origin
are divided into two main types (Skinner 2000 ), which are:
(i) essential, a normal part of the expected physiology of animal systems, such as
the mineral matter found in bones and teeth
and
(ii) unexpected, and undesired, or pathologic mineral deposits including stones
(renal, pancreatic, kidney), calculi (pancreatic and urinary),cystoliths, bladder
stones; gallstones rhinoliths (calculus present in the nasal cavity); tonsilloliths
(oropharyngeal concretions); vaginoliths—vaginal calculi; cardiolytes, cutaneous calculi, enteroliths; sialoliths—salivary submandibular and parotid
gland stones; ptyaliths—calculus in a salivary glands; dental calculi (see for
review Ehrlich et al. 2008 ). “The formation of crystals in pathological mineralization follows the same principles as normal calcifi cations,” (Ehrlich et al.
2008 ; see for more information Magalhaes et al. 2006 ). The mechanism of
formation of the calcium carbonate stones remains unclear. In some species, it
is thought that formation occurs due to precipitation surrounding an organic
nidus, such as proteins, cellular debris, crystals, or foreign bodies (Confer and
Panciera 1995 ).
Struvite seems to be the next mineral often seen in different pathological
cases. Struvite (NH 4 MgPO 4 •6H 2 O) is a magnesium ammonium phosphate hexahydrate. Struvite crystals are the orthorhombic and appear as brownish-white, or white
to yellowish pyramidal crystals. Also platy mica-like forms of struvite have been
described. With Mohs hardness of 1.5–2 and a low specifi c gravity of 1.7, it is
related to the soft minerals. Struvite is well soluble in acids, however sparingly
soluble in neutral and alkaline conditions (see for review Ferraris et al. 1986 ).
In some cases, known for humans and animals, ammonia-producing microorganisms are responsible for formation of struvite urinary stones and crystals. Also
high magnesium/plant-based diets lead to this kind of pathological biomineralization
(Osborne et al. 1985 ).
3 Biocomposites and Mineralized Tissues
3.7 Pathological Biomineralization in Marine Vertebrates
Abstract The formation of crystalline structures in pathological mineralization
follows the same principles as normal biomineralization. The mechanism of formation of various stones in organisms of marine vertebrates remains unclear. Stones
consist of several kinds of minerals like struvite, calcium carbonate and phosphate;
either alone or in combination. Different types of calculi (dental, nasal, renal, vaginal,
cystic) as well as stones (uroliths, nephroliths, enteroliths, faecoliths) observed in
fi sh, reptilians and marine mammals are described and discussed in this chapter.
According to the classical defi nition proposed by Catherine Skinner “Biominerals
may be deposited within the organism, and within its immediate surroundings or
environment, as a result of the metabolism of the living creature, ” (Ehrlich et al.
2008 ; see for more information Skinner 2000 ). Biominerals of the vertebrates origin
are divided into two main types (Skinner 2000 ), which are:
(i) essential, a normal part of the expected physiology of animal systems, such as
the mineral matter found in bones and teeth
and
(ii) unexpected, and undesired, or pathologic mineral deposits including stones
(renal, pancreatic, kidney), calculi (pancreatic and urinary),cystoliths, bladder
stones; gallstones rhinoliths (calculus present in the nasal cavity); tonsilloliths
(oropharyngeal concretions); vaginoliths—vaginal calculi; cardiolytes, cutaneous calculi, enteroliths; sialoliths—salivary submandibular and parotid
gland stones; ptyaliths—calculus in a salivary glands; dental calculi (see for
review Ehrlich et al. 2008 ). “The formation of crystals in pathological mineralization follows the same principles as normal calcifi cations,” (Ehrlich et al.
2008 ; see for more information Magalhaes et al. 2006 ). The mechanism of
formation of the calcium carbonate stones remains unclear. In some species, it
is thought that formation occurs due to precipitation surrounding an organic
nidus, such as proteins, cellular debris, crystals, or foreign bodies (Confer and
Panciera 1995 ).
Struvite seems to be the next mineral often seen in different pathological
cases. Struvite (NH 4 MgPO 4 •6H 2 O) is a magnesium ammonium phosphate hexahydrate. Struvite crystals are the orthorhombic and appear as brownish-white, or white
to yellowish pyramidal crystals. Also platy mica-like forms of struvite have been
described. With Mohs hardness of 1.5–2 and a low specifi c gravity of 1.7, it is
related to the soft minerals. Struvite is well soluble in acids, however sparingly
soluble in neutral and alkaline conditions (see for review Ferraris et al. 1986 ).
In some cases, known for humans and animals, ammonia-producing microorganisms are responsible for formation of struvite urinary stones and crystals. Also
high magnesium/plant-based diets lead to this kind of pathological biomineralization
(Osborne et al. 1985 ).
3 Biocomposites and Mineralized Tissues