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Stjepko Golubic - One of the best experts on this subject based on the ideXlab platform.
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mussel Periostracum from deep sea redox communities as a microbial habitat 3 secondary inhabitants
Marine Ecology, 1992Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Vacated microborings in Periostracum of live mussels of the Florida Escarpment redox community (depth of 3266 m) become a habitat for a prolific secondary microbiota consisting of a variety of prokaryotic and a few eukaryotic organisms. Periostracum surface is also colonized by diverse microorganisms, dominated by presumed chemolithotrophic bacteria with stacks of intracellular lamellae. Unlike sheltered microflora within borings, the surface community is heavily grazed upon by numerous archaeogastropods and ciliates.
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Mussel Periostracum from Deep‐Sea Redox Communities as a Microbial Habitat: 3. Secondary Inhabitants
Marine Ecology, 1992Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Vacated microborings in Periostracum of live mussels of the Florida Escarpment redox community (depth of 3266 m) become a habitat for a prolific secondary microbiota consisting of a variety of prokaryotic and a few eukaryotic organisms. Periostracum surface is also colonized by diverse microorganisms, dominated by presumed chemolithotrophic bacteria with stacks of intracellular lamellae. Unlike sheltered microflora within borings, the surface community is heavily grazed upon by numerous archaeogastropods and ciliates.
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Mussel Periostracum from Deep-Sea Redox Communities as a Microbial Habitat: 2. The Pit Borers
Marine Ecology, 1990Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Mussel Periostracum from the Florida Escarpment redox community (3266 m depth) is extensively bored by a variety of microorganisms. Four different types of pit borings were observed and characterized on the basis of SEM images of their resin casts, and/or light and TEM reconstructions: two large, open-pit borers, a “button” borer, and a cone borer. These boring patterns represent distinctive feeding “strategies”. The cumulative activities of Periostracum borers remove the protective organic layer from the mussel shells, exposing the mineral to cndolith attack.
Qian Mao - One of the best experts on this subject based on the ideXlab platform.
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quality consistency evaluation on four origins of cicadae Periostracum by ultra performance liquid chromatography coupled with quadrupole time of flight mass spectrometry analysis
Journal of Pharmaceutical and Biomedical Analysis, 2020Co-Authors: Xin-ci Cao, Xiao-ya Zhang, Hong Shen, Shan-shan Zhou, He Zhu, Ming Kong, Wei Zhang, Gui-rong Zhou, Qian MaoAbstract:Abstract Cicadae Periostracum, which is derived from the slough of Cicadidae insects, is a commonly used crude drug in traditional Chinese medicine (TCM). As specified in Chinese Pharmacopoeia, Cryptotympana atrata (CA) is the only official species of this crude drug. However, the slough of other three species, i.e., Auritibicen flammatus (AF), Cryptotympana mandrina (CM) and Platypleura kaempferi (PK), have been also used as the origins of Cicadae Periostracum in Chinese herbal market, although whether the quality of these four origins is consistent or not is still unknown. In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was employed to qualitatively and quantitatively compare the chemical profiles of the four origins. Totally, 34 N-acetyldopamine polymers were identified from the four origins, including 4 N-acetyldopamine dimers, 11 N-acetyldopamine trimers, 10 N-acetyldopamine tetramers, and 9 N-acetyldopamine pentamers. AF, CM and PK had similar chemical profiles with that of CA. The contents and compositional ratio of the four types of polymers in CA, AF and CM were consistent with each other, but significantly lower or different in PK. All these results suggested that AF and CM might be considered as the potential resources of Cicadae Periostracum concerning their consistent holistic quality, whereas whether PK could be used as potential origin of Cicadae Periostracum or not need further evaluation for their different compositional ratios and contents of the four types of N-acetyldopamine polymers. This is the first study on chemical profiling and comparison of N-acetyldopamine polymers in four origins of Cicadae Periostracum, which is beneficial for potential resources utilization and quality standard improvement of Cicadae Periostracum.
Xin-ci Cao - One of the best experts on this subject based on the ideXlab platform.
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quality consistency evaluation on four origins of cicadae Periostracum by ultra performance liquid chromatography coupled with quadrupole time of flight mass spectrometry analysis
Journal of Pharmaceutical and Biomedical Analysis, 2020Co-Authors: Xin-ci Cao, Xiao-ya Zhang, Hong Shen, Shan-shan Zhou, He Zhu, Ming Kong, Wei Zhang, Gui-rong Zhou, Qian MaoAbstract:Abstract Cicadae Periostracum, which is derived from the slough of Cicadidae insects, is a commonly used crude drug in traditional Chinese medicine (TCM). As specified in Chinese Pharmacopoeia, Cryptotympana atrata (CA) is the only official species of this crude drug. However, the slough of other three species, i.e., Auritibicen flammatus (AF), Cryptotympana mandrina (CM) and Platypleura kaempferi (PK), have been also used as the origins of Cicadae Periostracum in Chinese herbal market, although whether the quality of these four origins is consistent or not is still unknown. In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was employed to qualitatively and quantitatively compare the chemical profiles of the four origins. Totally, 34 N-acetyldopamine polymers were identified from the four origins, including 4 N-acetyldopamine dimers, 11 N-acetyldopamine trimers, 10 N-acetyldopamine tetramers, and 9 N-acetyldopamine pentamers. AF, CM and PK had similar chemical profiles with that of CA. The contents and compositional ratio of the four types of polymers in CA, AF and CM were consistent with each other, but significantly lower or different in PK. All these results suggested that AF and CM might be considered as the potential resources of Cicadae Periostracum concerning their consistent holistic quality, whereas whether PK could be used as potential origin of Cicadae Periostracum or not need further evaluation for their different compositional ratios and contents of the four types of N-acetyldopamine polymers. This is the first study on chemical profiling and comparison of N-acetyldopamine polymers in four origins of Cicadae Periostracum, which is beneficial for potential resources utilization and quality standard improvement of Cicadae Periostracum.
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Quality consistency evaluation on four origins of Cicadae Periostracum by ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry analysis.
Journal of Pharmaceutical and Biomedical Analysis, 2020Co-Authors: Xin-ci Cao, Xiao-ya Zhang, Hong Shen, Shan-shan Zhou, He Zhu, Ming Kong, Wei Zhang, Gui-rong ZhouAbstract:Abstract Cicadae Periostracum, which is derived from the slough of Cicadidae insects, is a commonly used crude drug in traditional Chinese medicine (TCM). As specified in Chinese Pharmacopoeia, Cryptotympana atrata (CA) is the only official species of this crude drug. However, the slough of other three species, i.e., Auritibicen flammatus (AF), Cryptotympana mandrina (CM) and Platypleura kaempferi (PK), have been also used as the origins of Cicadae Periostracum in Chinese herbal market, although whether the quality of these four origins is consistent or not is still unknown. In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was employed to qualitatively and quantitatively compare the chemical profiles of the four origins. Totally, 34 N-acetyldopamine polymers were identified from the four origins, including 4 N-acetyldopamine dimers, 11 N-acetyldopamine trimers, 10 N-acetyldopamine tetramers, and 9 N-acetyldopamine pentamers. AF, CM and PK had similar chemical profiles with that of CA. The contents and compositional ratio of the four types of polymers in CA, AF and CM were consistent with each other, but significantly lower or different in PK. All these results suggested that AF and CM might be considered as the potential resources of Cicadae Periostracum concerning their consistent holistic quality, whereas whether PK could be used as potential origin of Cicadae Periostracum or not need further evaluation for their different compositional ratios and contents of the four types of N-acetyldopamine polymers. This is the first study on chemical profiling and comparison of N-acetyldopamine polymers in four origins of Cicadae Periostracum, which is beneficial for potential resources utilization and quality standard improvement of Cicadae Periostracum.
James E. Hook - One of the best experts on this subject based on the ideXlab platform.
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mussel Periostracum from deep sea redox communities as a microbial habitat 3 secondary inhabitants
Marine Ecology, 1992Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Vacated microborings in Periostracum of live mussels of the Florida Escarpment redox community (depth of 3266 m) become a habitat for a prolific secondary microbiota consisting of a variety of prokaryotic and a few eukaryotic organisms. Periostracum surface is also colonized by diverse microorganisms, dominated by presumed chemolithotrophic bacteria with stacks of intracellular lamellae. Unlike sheltered microflora within borings, the surface community is heavily grazed upon by numerous archaeogastropods and ciliates.
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Mussel Periostracum from Deep‐Sea Redox Communities as a Microbial Habitat: 3. Secondary Inhabitants
Marine Ecology, 1992Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Vacated microborings in Periostracum of live mussels of the Florida Escarpment redox community (depth of 3266 m) become a habitat for a prolific secondary microbiota consisting of a variety of prokaryotic and a few eukaryotic organisms. Periostracum surface is also colonized by diverse microorganisms, dominated by presumed chemolithotrophic bacteria with stacks of intracellular lamellae. Unlike sheltered microflora within borings, the surface community is heavily grazed upon by numerous archaeogastropods and ciliates.
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Mussel Periostracum from Deep-Sea Redox Communities as a Microbial Habitat: 2. The Pit Borers
Marine Ecology, 1990Co-Authors: James E. Hook, Stjepko GolubicAbstract:. Mussel Periostracum from the Florida Escarpment redox community (3266 m depth) is extensively bored by a variety of microorganisms. Four different types of pit borings were observed and characterized on the basis of SEM images of their resin casts, and/or light and TEM reconstructions: two large, open-pit borers, a “button” borer, and a cone borer. These boring patterns represent distinctive feeding “strategies”. The cumulative activities of Periostracum borers remove the protective organic layer from the mussel shells, exposing the mineral to cndolith attack.
Antonio G. Checa - One of the best experts on this subject based on the ideXlab platform.
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Cuticle of Polyplacophora: structure, secretion, and homology with the Periostracum of conchiferans
Marine Biology, 2017Co-Authors: Antonio G. Checa, Michael J. Vendrasco, Carmen SalasAbstract:The plesiomorphic state of the molluscan scleritome remains ambiguous. Chitons are significant because they show a mix of characters considered diagnostic in both aplacophorans and conchiferans, with both shell plates and small calcified girdle elements on an elongate body, and there is no consensus on the homology of structures involved in chiton plate calcification with those in conchiferan shells. Using light, scanning, and transmission microscopy, the present study examined the structure and formation of the cuticle and underlying epithelium in five chiton species collected over several years in southeast Spain and in California, USA. The cuticular matrix in chitons is similar to the translucent layer of the bivalve Periostracum, although there are differences in the orientation of the densely spaced laminae with respect to the mantle surface. The cuticle arises in the accessory fold of the ventral girdle mantle. There is full continuity between the outermost layer of the cuticle and the thin outer layer of the tegmentum, suggesting that the latter is derived from the cuticular wedge permanently lying on the plate margins. A homology is proposed between the cuticle/associated girdle mantle epithelium of Polyplacophora and the Periostracum/inner side of the outer mantle fold of the Bivalvia. Nevertheless, while the bivalve Periostracum slides over the mantle epithelium during growth, the polyplacophoran cuticle remains stationary. The configuration of the cuticle, which overlaps the plate margins, allows it to efficiently close the plate biomineralization compartment, in a way comparable to that of the Periostracum of conchiferans.
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Biosorption of thorium on the external shell surface of bivalve mollusks: The role of shell surface microtopography
Chemosphere, 2012Co-Authors: Michael Zuykov, Antonio G. Checa, Émilien Pelletier, Richard Saint-louis, Serge DemersAbstract:External shell surface (ESS) of bivalve mollusks is known to adsorb various metals dissolved in ambient water in high concentration. It is hypothesized here that the surface microtopography of the thin organic coating layer, Periostracum, or calcareous shell (if Periostracum was destroyed) plays a major role in the adsorption of actinides on ESS. Thorium (natural alpha-emitter) was used in short-term biosorption experiment with shell fragments of five bivalve mollusks. After a 72 h exposure to Th (~6 kBq L(-1)), thorium concentration was measured on ESS using laser ablation inductively coupled plasma mass spectrometry; the distribution and density of alpha tracks were subsequently visualized by α-track autoradiography. A trend in reduced Th concentrations on the ESS was observed depending upon the species tested: (group 1 ~4000 μg g(-1)) Chlamys islandica (M.), Mercenaria mercenaria (L.), Dreissena polymorpha (P.)>(group 2 ~1200 μg g(-1)) Crassostrea virginica (G.)≫(group 3 ~150 μg g(-1)) Mytilus edulis L. The microtopography of ESS was characterized by scanning electron microscopy revealing the high porosity of the calcareous surface of C. islandica and M. mercenaria, lamellate surface of Periostracum in D. polymorpha, uneven but a weakly porous surface of Periostracum of C. virginica, and a nearly smooth surface of the Periostracum of M. edulis. This work has demonstrated, for the first time, the presence of a strong correlation between concentration of adsorbed Th and ESS microtopography, and the role of the Periostracum in this process is discussed.
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The Periostracum of Digitaria digitaria (Bivalvia: Astartidae): formation and structure
Journal of Molluscan Studies, 2011Co-Authors: Carmen Salas, Antonio G. Checa, Pablo Marina, José L. RuedaAbstract:The formation, structure and growth of the Periostracum of Digitaria digitaria (L., 1758), a small species of the family Astartidae from the temperate eastern Atlantic and Mediterranean, was studied. The Periostracum originates from a row of basal cells, located at the bottom of the periostracal groove. It is initially secreted in the intercellular space between the basal cell row and the first cell row of the outer and middle folds; at this point this Periostracum consists of a thin membrane, which comprises two layers (granular and dark homogeneous). The inner epithelial cells of the outer fold are responsible for the secretion and thickening of the third, translucent layer. Along and across the periostracal groove, the Periostracum adheres to the outer epithelial cells of the middle mantle fold and develops an undulating form. We observed that the dark layer of the Periostracum thickens across the periostracal groove. We could not confirm the involvement of the middle mantle fold in this thickening; a tanning process of the translucent layer appears to be a more likely alternative. During the free Periostracum stage the translucent layer is no longer secreted and it becomes transformed into dark layer through a tanning process, which implies a noticeable reduction in periostracal thickness. The outer layer of the Periostracum is pitted when newly formed and later the pits become filled by mucus and bacteria-like microorganisms. The first cell row of the outer epithelium of the middle fold serves as template for the large periostracal pits, while the small pits correspond to minor projections of the cells. The mode of formation of pits implies that, rather than being continuous, the periostracal growth proceeds in pulses. The microvilli of the inner epithelial cells of the outer fold show a linear border, while the microvilli of the outer epithelial cells from the apical part of the middle fold show an undulating form. These large undulations of the microvilli in the distal part of the middle fold loosely attach to the Periostracum and ease its extrusion from the periostracal groove. This study has also revealed the presence of sensory organs in the distal edge of the middle mantle fold.
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A new model for Periostracum and shell formation in Unionidae (Bivalvia, Mollusca).
Tissue and Cell, 2000Co-Authors: Antonio G. ChecaAbstract:The Periostracum in Unionidae consists of two layers. The outer one is secreted within the periostracal groove, while the inner layer is secreted by the epithelium of the outer mantle fold. The Periostracum reaches its maximum thickness at the shell edge, where it reflects onto the shell surface. Biomineralization begins within the inner Periostracum as fibrous spheruliths, which grow towards the shell interior, coalesce and compete mutually, originating the aragonitic outer prismatic shell layer. Prisms are fibrous polycrystalline aggregates. Internal growth lines indicate that their growth front is limited by the mantle surface. Transition to nacre is gradual. The first nacreous tablets grow by epitaxy onto the distal ends of prism fibres. Later growth proceeds onto previously deposited tablets. Our model involves two alternative stages. During active shell secretion, the mantle edge extends to fill the extrapallial space and the periostracal conveyor belt switches on, with the consequential secretion of Periostracum and shell. During periods of inactivity, only the outer Periostracum is secreted; this forms folds at the exit of the periostracal groove, leaving high-rank growth lines. Layers of inner Periostracum are added occasionally to the shell interior during prolonged periods of inactivity in which the mantle is retracted.
