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Terrestrial isopods (Crustacea) are excellent model organisms to study epithelial calcium-transport and the regulation of biomineralization processes. They molt frequently and resorb cuticular CaCO 3 before the molt to prevent excessive loss of Ca 2+ ions when the old cuticle is shed. The resorbed mineral is stored in CaCO 3 deposits within the ecdysial gap of the first four...
Since the early 19th century, the skeletons of calcareous sponges (Porifera: Calcarea) with their mineralized spicules have been investigated for their morphologies, structures, and mineralogical and organic compositions. These biomineral spicules, up to about 10mm in size, with one to four rays called actines, have various specific shapes and consist mainly of magnesium-calcite: in only one case...
The thin sheets of calcite in oyster shell in Crassostrea gigas are termed folia and comprise much of the oyster shell. The folia are covered by a layer of discrete globules that has been proposed to consist of aggregations of an organic matrix and minerals. A continuous organic framework divides each tablet into nanograins. Their shape is globular with a mean extension from 30 to 40nm. Chemical and...
This is the second paper on principles of demineralization. The initial paper is dedicated to the common definitions and the history of demineralization. In present work we review the principles and mechanisms of decalcification, i.e., removing the mineral Ca-containing compounds (phosphates and carbonates) from the organic matrix in its two main aspects: natural and artificial. Natural chemical erosion...
Anatomical descriptions are provided on silicified woods from a Tertiary basin Pohang, Korea by scanning electron microscopy and X-ray microanalysis. The silicified woods appeared to retain the original exterior morphology of the once grown trees, and exhibited various colors on the surface. As a component of the axial system in the secondary xylem, pores were oval to globose and measured approximately...
Ferromanganese [Fe/Mn] crusts formed on basaltic seamounts, gain considerable economic importance due to their high content of Co, Ni, Cu, Zn and Pt. The deposits are predominantly found in the Pacific Ocean in depths of over 1000m. They are formed in the mixing layer between the upper oxygen-minimum zone and the lower oxygen-rich bottom zone. At present an almost exclusive abiogenic origin of crust...
Inspired by the phenomenological differences of layers in oyster shell and the morphological mimicry of SiO 2 thin film, a folded-structure SiO 2 was created by simple spray deposition system. The folded-structure SiO 2 was analyzed by scanning electron microscopy, energy dispersive spectrometer and microindentation. At the molecular level, the chalky and the folia were assembled...
This study focuses on the separation and storage of the global warming greenhouse gas CO 2 , and the use of natural biocatalysts in the development of technologies to improve CO 2 storage rates and provide new methods for CO 2 capture. Carbonic anhydrase (CA) has recently been used as a biocatalyst to sequester CO 2 through the conversion of CO 2 to HCO ...
A 48kDa acidic and putative calcium-binding glycoprotein was isolated from pearls of the freshwater mussel Hyriopsis cumingii. This protein was compared with a related 46kDa polypeptide, obtained from the nacreous shell of the same species. Separation by two-dimensional gel electrophoresis revealed that the difference in molecular weight is due to the higher extent of glycosylation of the 48kDa protein...
The complex crossed structures with a polymorph of calcite, termed a chalky layer, which make up much of the shell of an oyster, are composed of flames and leaflets. Two layers, folia and the chalky layer in the giant Pacific oyster (Crassostrea gigas) were examined using SEM (scanning electron microscope), micro-area-XRD (X-ray diffraction) and FT-IR (Fourier transform infrared spectrometer) to determine...
Atomic force microscopy (AFM) was used in concert with transmission electron microscopy (TEM) to image magnetotactic bacteria (Magnetospirillum gryphiswaldense MSR-1 and Magnetospirillum magneticum AMB-1), magnetosomes, and purified Mms6 proteins. Mms6 is a protein that is associated with magnetosomes in M. magneticum AMB-1 and is believed to control the synthesis of magnetite (Fe 3 O ...
Amorphous mineral granules are formed by concentric mineral layers containing polyphosphate, pyrophosphate and/or orthophosphate and several metallic cations such as Mg 2+ , Ca 2+ , K + , Mn 2+ , Fe 3+ , Cu 2+ , and Zn 2+ . In this work, we analyzed amorphous mineral granules isolated from the ant species Camponotus abdominalis, Camponotus sp...
A microstructural and mineralogical study shows the transition of aragonitic nacreous tablets to aragonitic prisms inside previously secreted nacre, i.e. without contact with the mantle or extrapallial fluid, in a field-collected mytilid bivalve Crenomytilus grayanus (D.). The intermediate zone between nacre and new prisms is represented by nacre tablets “stuck together” or by disordered calcium carbonate...
Mesocestoides corti (syn. vogae), similar to many other cestode platyhelminthes, contains abundant calcium carbonate structures called calcareous corpuscles. These concretions that may constitute as much as 40% of the dry weight of the body, and were proposed to form intracellularly in certain parenchymal cells. As an approach to elucidate the biological role of calcareous corpuscles in cestodes,...
Strontium ranelate has been used to prevent bone loss and stimulate bone regeneration. Although strontium may integrate into the bone crystal lattice, the chemical and structural modifications of the bone when strontium interacts with the mineral phase are not completely understood. The objective of this study was to evaluate apatite from the mandibles of rats treated with strontium ranelate in the...
Calcium carbonate crystals are known to form in the yolk sacs of fertile pigeon eggs at late stages of incubation. The composition and structure of these crystals were investigated, the crystallization environment was inspected, and the physical chemistry constants of the yolk fluid were determined through the incubation period. Polarized light microscopy was used to observe the generation and distribution...
The interest in effects of strontium (Sr) on bone has greatly increased in the last decade due to the development of the promising drug strontium ranelate. This drug is used for treating osteoporosis, a major bone disease affecting hundreds of millions of people worldwide, especially postmenopausal women. The novelty of strontium ranelate compared to other treatments for osteoporosis is its unique...
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