Base de dados : MEDLINE
Pesquisa : D01.146.275.500 [Categoria DeCS]
Referências encontradas : 149 [refinar]
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[PMID]:28652139
[Au] Autor:Zhang H; Zhao M; Yi X; Ou Z; Li Y; Shi Y; He M
[Ad] Endereço:CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangdong, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China.
[Ti] Título:Characterization of the distal-less homologue gene, PfDlx, involved in regulating the expression of Pif in the pearl oyster, Pinctada fucata.
[So] Source:Comp Biochem Physiol B Biochem Mol Biol;212:51-58, 2017 Oct.
[Is] ISSN:1879-1107
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Distal-less (Dlx) homeobox transcription factors play an important role in regulating various aspects of vertebrate biology. In vertebrates and invertebrates, distal-less is a highly conserved and well-studied transcription factor. In pearl oyster, we have identified a homologue of this gene, Dlx, and cloned the full-length cDNA. Genomic structure analysis revealed that PfDlx genomic DNA contained three exons and two introns. Their deduced amino acid sequences all showed the highest identity with homologues in Crassostrea gigas. Analyses of PfDlx mRNA in tissues and developmental stages showed high expressions in gonad, polar body stage, 2-4 cells and 32 cells. After shell notching, the changes in expression of Dlx shows that it reached a maximum at 24h. In co-transfection experiments, PfDlx significantly activates reporter constructs containing a Pif promoter. Through using RNAi techniques, we demonstrated that down-regulation of Dlx in P. fucata did not significantly disrupt the development of the nacreous layer in scanning electron microscopy, but it significantly down-regulated the expression of Pif gene. Thus, our work suggests that PfDlx might participate in regulating the expression of the Pif gene in the pearl oyster.
[Mh] Termos MeSH primário: Proteínas de Homeodomínio/genética
Pinctada/genética
Fatores de Transcrição/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Linhagem Celular
Clonagem Molecular
DNA Complementar/genética
Regulação da Expressão Gênica no Desenvolvimento
Proteínas de Homeodomínio/química
Proteínas de Homeodomínio/metabolismo
Modelos Moleculares
Nácar/metabolismo
Filogenia
Pinctada/crescimento & desenvolvimento
Pinctada/metabolismo
Regiões Promotoras Genéticas
Conformação Proteica
Interferência de RNA
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Homologia de Sequência de Aminoácidos
Distribuição Tecidual
Fatores de Transcrição/química
Fatores de Transcrição/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Distal-less homeobox proteins); 0 (Homeodomain Proteins); 0 (Nacre); 0 (RNA, Messenger); 0 (Transcription Factors)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE


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[PMID]:28649833
[Au] Autor:Jain G; Pendola M; Huang YC; Juan Colas J; Gebauer D; Johnson S; Evans JS
[Ad] Endereço:Laboratory for Chemical Physics, Center for Skeletal and Craniofacial Biology, New York University , 345 East 24th Street, New York, New York 10010, United States.
[Ti] Título:Functional Prioritization and Hydrogel Regulation Phenomena Created by a Combinatorial Pearl-Associated Two-Protein Biomineralization Model System.
[So] Source:Biochemistry;56(28):3607-3618, 2017 Jul 18.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the nacre or aragonitic layer of an oyster pearl, there exists a 12-member proteome that regulates both the early stages of nucleation and nanoscale-to-mesoscale assembly of nacre tablets and calcitic crystals from mineral nanoparticle precursors. Several approaches to understanding protein-associated mechanisms of pearl nacre formation have been developed, yet we still lack insight into how protein ensembles or proteomes manage nucleation and crystal growth. To provide additional insights, we have created a proportionally defined combinatorial model consisting of two pearl nacre-associated proteins, PFMG1 and PFMG2 (shell oyster pearl nacre, Pinctada fucata) whose individual in vitro mineralization functionalities are distinct from one another. Using scanning electron microscopy, atomic force microscopy, Ca(II) potentiometric titrations, and quartz crystal microbalance with dissipation monitoring quantitative analyses, we find that at 1:1 molar ratios, rPFMG2 and rPFMG1 co-aggregate in specific molecular ratios to form hybrid hydrogels that affect both the early and later stages of in vitro calcium carbonate nucleation. Within these hybrid hydrogels, rPFMG2 plays a role in defining protein co-aggregation and hydrogel dimension, whereas rPFMG1 defines participation in nonclassical nucleation processes; both proteins exhibit synergy with regard to surface and subsurface modifications to existing crystals. The interactions between both proteins are enhanced by Ca(II) ions and may involve Ca(II)-induced conformational events within the EF-hand rPFMG1 protein, as well as putative interactions between the EF-hand domain of rPFMG1 and the calponin-like domain of rPFMG2. Thus, the pearl-associated PFMG1 and PFMG2 proteins interact and exhibit mineralization functionalities in specific ways, which may be relevant for pearl formation.
[Mh] Termos MeSH primário: Hidrogel de Polietilenoglicol-Dimetacrilato/metabolismo
Nácar/metabolismo
Pinctada/metabolismo
Proteínas/metabolismo
[Mh] Termos MeSH secundário: Animais
Proteínas de Ligação ao Cálcio/química
Cristalização
Motivos EF Hand
Proteínas dos Microfilamentos/química
Microscopia de Força Atômica
Microscopia Eletrônica de Varredura
Modelos Moleculares
Pinctada/ultraestrutura
Agregados Proteicos
Domínios Proteicos
Proteínas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Calcium-Binding Proteins); 0 (Microfilament Proteins); 0 (Nacre); 0 (Protein Aggregates); 0 (Proteins); 0 (calponin); 25852-47-5 (Hydrogel, Polyethylene Glycol Dimethacrylate)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170627
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00313


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[PMID]:28123096
[Au] Autor:Marie B; Arivalagan J; Mathéron L; Bolbach G; Berland S; Marie A; Marin F
[Ad] Endereço:UMR 7245 CNRS/MNHN Molécules de Communications et Adaptations des Micro-organismes, Muséum National d'Histoire Naturelle, Sorbonne Universités, Paris, France bmarie@mnhn.fr.
[Ti] Título:Deep conservation of bivalve nacre proteins highlighted by shell matrix proteomics of the Unionoida Elliptio complanata and Villosa lienosa.
[So] Source:J R Soc Interface;14(126), 2017 Jan.
[Is] ISSN:1742-5662
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The formation of the molluscan shell nacre is regulated to a large extent by a matrix of extracellular macromolecules that are secreted by the shell-forming tissue, the mantle. This so-called 'calcifying matrix' is a complex mixture of proteins, glycoproteins and polysaccharides that is assembled and occluded within the mineral phase during the calcification process. Better molecular-level characterization of the substances that regulate nacre formation is still required. Notable advances in expressed tag sequencing of freshwater mussels, such as Elliptio complanata and Villosa lienosa, provide a pre-requisite to further characterize bivalve nacre proteins by a proteomic approach. In this study, we have identified a total of 48 different proteins from the insoluble matrices of the nacre, 31 of which are common to both E. complanata and V. lienosa A few of these proteins, such as PIF, MSI60, CA, shematrin-like, Kunitz-like, LamG, chitin-binding-containing proteins, together with A-, D-, G-, M- and Q-rich proteins, appear to be analogues, if not true homologues, of proteins previously described from the pearl oyster or the edible mussel nacre matrices, thus forming a remarkable list of deeply conserved nacre proteins. This work constitutes a comprehensive nacre proteomic study of non-pteriomorphid bivalves that has enabled us to describe the molecular basis of a deeply conserved biomineralization toolkit among nacreous shell-bearing bivalves, with regard to proteins associated with other shell microstructures, with those of other mollusc classes (gastropods, cephalopods) and, finally, with other lophotrochozoans (brachiopods).
[Mh] Termos MeSH primário: Calcificação Fisiológica/fisiologia
Evolução Molecular
Proteínas da Matriz Extracelular
Nácar
Unionidae
[Mh] Termos MeSH secundário: Exoesqueleto/química
Exoesqueleto/metabolismo
Animais
Proteínas da Matriz Extracelular/química
Proteínas da Matriz Extracelular/classificação
Proteínas da Matriz Extracelular/genética
Proteínas da Matriz Extracelular/metabolismo
Nácar/química
Nácar/genética
Nácar/metabolismo
Proteômica
Unionidae/química
Unionidae/classificação
Unionidae/genética
Unionidae/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Extracellular Matrix Proteins); 0 (Nacre)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170127
[St] Status:MEDLINE


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[PMID]:27987723
[Au] Autor:Lee Y; Kim BY; Shin DG; Kim SR; Kwon WT; Kim Y
[Ad] Endereço:Energy & Environment Division, Korea Institute of Ceramic Engineering and Technology, 101 Soho-ro, Jinju 52851, Republic of Korea.
[Ti] Título:Effects of asperities and organic-inorganic interactions on the strength of nacre-mimetic composites.
[So] Source:Mater Sci Eng C Mater Biol Appl;71:395-400, 2017 Feb 01.
[Is] ISSN:1873-0191
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Nacre is a natural organic-inorganic hybrid composite, whose hierarchical structure has a complex influence on its high strength. Many structural features have been discovered, which influence the mechanical properties of nacre, and the authors have a particular interest in the role of the asperities and organic-inorganic interactions. In this study, a composite was prepared which mimics the asperity structure using clay minerals. Organic-inorganic bonding was induced with silane treatment. Both factors increased the yield strength of the composites; however, different deformation behavior was exhibited. It was found that asperities improved the strength of the composite, and that composition influences the stiffness of the composite. The organic-inorganic interaction between the resin and the other components of the composite reduced the deformation of the composite and consequently improved strength.
[Mh] Termos MeSH primário: Bis-Fenol A-Glicidil Metacrilato/química
Nácar/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nacre); 454I75YXY0 (Bisphenol A-Glycidyl Methacrylate); 79586-00-8 (Silar (3M))
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161219
[St] Status:MEDLINE


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[PMID]:27838409
[Au] Autor:Chen X; Liu X; Bai Z; Zhao L; Li J
[Ad] Endereço:Key Laboratory of Freshwater Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Agriculture, Shanghai 201306, China.
[Ti] Título:HcTyr and HcTyp-1 of Hyriopsis cumingii, novel tyrosinase and tyrosinase-related protein genes involved in nacre color formation.
[So] Source:Comp Biochem Physiol B Biochem Mol Biol;204:1-8, 2017 Feb.
[Is] ISSN:1879-1107
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Tyrosinase is an important enzyme that is involved in biological processes such as pigmentation, wound healing, sclerotization of the cuticles, oxygen transport and innate immunity. As nacre color has an effect on pearl color, we studied the effect of tyrosinase on nacre color in Hyriopsis cumingii (an important freshwater pearl-producing mussel) by cloning novel tyrosinase protein and tyrosinase-related protein genes (HcTyr and HcTyp-1 respectively) from the mantle. The predicted amino acid sequences of HcTyr and HcTyp-1 contain conserved domains, and HcTyp-1 contains an additional chitin-binding domain. Two different types of mussels, purple shelled and white shelled, were used to investigate the role of tyrosinase in shell color. HcTyr and HcTyp-1 mRNAs were mainly expressed in the mantle, but the expression of HcTyr was higher in the purple mussel than in the white mussel while the expression of HcTyp-1 was higher in the white mussel. Strong and specific mRNA signals for HcTyp-1 were detected in the dorsal epithelial cells of the mantle pallial and some signals were detected in the epithelial cells of the periostracal groove, so HcTyp-1 may be involved in periostracum and nacreous layer formation. Strong and specific mRNA signals were also detected in the dorsal epithelial cells of the mantle pallial, so HcTyr may be involved in nacre formation. Further, the tyrosinase activity of the mantle in the purple mussel was higher than that in the white mussel. These findings indicate that HcTyr and HcTyp-1 may be involved in the formation of nacre color in H. cumingii.
[Mh] Termos MeSH primário: Monofenol Mono-Oxigenase/genética
Nácar/metabolismo
Pigmentação/genética
Unionidae/genética
Unionidae/metabolismo
[Mh] Termos MeSH secundário: Animais
Clonagem Molecular
DNA Complementar/genética
Regulação Enzimológica da Expressão Gênica
Filogenia
Alinhamento de Sequência
Análise de Sequência de DNA
Unionidae/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Nacre); EC 1.14.18.1 (Monophenol Monooxygenase)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170201
[Lr] Data última revisão:
170201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161114
[St] Status:MEDLINE


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[PMID]:27750380
[Au] Autor:Zhang G; Brion A; Willemin AS; Piet MH; Moby V; Bianchi A; Mainard D; Galois L; Gillet P; Rousseau M
[Ad] Endereço:Faculté de médicine, IMoPA, UMR 7365 CNRS Université de Lorraine, Vandoeuvre-lès-Nancy, France.
[Ti] Título:Nacre, a natural, multi-use, and timely biomaterial for bone graft substitution.
[So] Source:J Biomed Mater Res A;105(2):662-671, 2017 Feb.
[Is] ISSN:1552-4965
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:During the past two decades, with a huge and rapidly increasing clinical need for bone regeneration and repair, bone substitutes are more and more seen as a potential solution. Major innovation efforts are being made to develop such substitutes, some having advanced even to clinical practice. It is now time to turn to natural biomaterials. Nacre, or mother-of-pearl, is an organic matrix-calcium carbonate coupled shell structure produced by molluscs. In vivo and in vitro studies have revealed that nacre is osteoinductive, osteoconductive, biocompatible, and biodegradable. With many other outstanding qualities, nacre represents a natural and multi-use biomaterial as a bone graft substitute. This review aims at summarising the current needs in orthopaedic clinics and the challenges for the development of bone substitutes; most of all, we systematically review the physiological characteristics and biological evidence of nacre's effects centred on osteogenesis, and finally we put forward the potential use of nacre as a bone graft substitute. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 662-671, 2017.
[Mh] Termos MeSH primário: Regeneração Óssea/efeitos dos fármacos
Substitutos Ósseos/uso terapêutico
Nácar/uso terapêutico
Osteogênese/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Substitutos Ósseos/química
Seres Humanos
Nácar/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Bone Substitutes); 0 (Nacre)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161018
[St] Status:MEDLINE
[do] DOI:10.1002/jbm.a.35939


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[PMID]:27909912
[Au] Autor:Liang J; Xie J; Gao J; Xu CQ; Yan Y; Jia GC; Xiang L; Xie LP; Zhang RQ
[Ad] Endereço:Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
[Ti] Título:Identification and Characterization of the Lysine-Rich Matrix Protein Family in Pinctada fucata: Indicative of Roles in Shell Formation.
[So] Source:Mar Biotechnol (NY);18(6):645-658, 2016 Dec.
[Is] ISSN:1436-2236
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mantle can secret matrix proteins playing key roles in regulating the process of shell formation. The genes encoding lysine-rich matrix proteins (KRMPs) are one of the most highly expressed matrix genes in pearl oysters. However, the expression pattern of KRMPs is limited and the functions of them still remain unknown. In this study, we isolated and identified six new members of lysine-rich matrix proteins, rich in lysine, glycine and tyrosine, and all of them are basic matrix proteins. Combined with four members of the KRMPs previously reported, all these proteins can be divided into three subclasses according to the results of phylogenetic analyses: KRMP1-3 belong to subclass KPI, KRMP4-5 belong to KPII, and KRMP6-10 belong to KPIII. Three subcategories of lysine-rich matrix proteins are highly expressed in the D-phase, the larvae and adult mantle. Lysine-rich matrix proteins are involved in the shell repairing process and associated with the formation of the shell and pearl. What's more, they can cause abnormal shell growth after RNA interference. In detail, KPI subgroup was critical for the beginning formation of the prismatic layer; both KPII and KPIII subgroups participated in the formation of prismatic layer and nacreous layer. Compared with different temperatures and salinity stimulation treatments, the influence of changes in pH on KRMPs gene expression was the greatest. Recombinant KRMP7 significantly inhibited CaCO precipitation, changed the morphology of calcite, and inhibited the growth of aragonite in vitro. Our results are beneficial to understand the functions of the KRMP genes during shell formation.
[Mh] Termos MeSH primário: Exoesqueleto/metabolismo
Proteínas da Matriz Extracelular/genética
Larva/genética
Família Multigênica
Nácar/genética
Pinctada/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Exoesqueleto/crescimento & desenvolvimento
Animais
Carbonato de Cálcio/química
Clonagem Molecular
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas da Matriz Extracelular/química
Proteínas da Matriz Extracelular/classificação
Proteínas da Matriz Extracelular/metabolismo
Regulação da Expressão Gênica no Desenvolvimento
Concentração de Íons de Hidrogênio
Larva/crescimento & desenvolvimento
Larva/metabolismo
Nácar/metabolismo
Filogenia
Pinctada/classificação
Pinctada/crescimento & desenvolvimento
Pinctada/metabolismo
Proteínas Recombinantes/química
Proteínas Recombinantes/classificação
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Salinidade
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Extracellular Matrix Proteins); 0 (Nacre); 0 (Recombinant Proteins); H0G9379FGK (Calcium Carbonate)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161203
[St] Status:MEDLINE
[do] DOI:10.1007/s10126-016-9724-6


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[PMID]:27846481
[Au] Autor:Barthelat F
[Ad] Endereço:Department of Mechanical Engineering, McGill University, 817 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada. francois.barthelat@mcgill.ca.
[Ti] Título:Growing a synthetic mollusk shell.
[So] Source:Science;354(6308):32-33, 2016 Oct 07.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Exoesqueleto/química
Materiais Biomiméticos/química
Biomimética/métodos
Moluscos/química
Nácar/química
[Mh] Termos MeSH secundário: Exoesqueleto/ultraestrutura
Animais
Calcificação Fisiológica
Moluscos/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nacre)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170322
[Lr] Data última revisão:
170322
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161116
[St] Status:MEDLINE


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[PMID]:27554519
[Au] Autor:Libouban H; Pascaretti-Grizon F; Camprasse G; Camprasse S; Chappard D
[Ad] Endereço:GEROM - LHEA, Groupe études remodelage osseux et biomatériaux, IRIS-IBS institut de biologie en santé, université d'Angers, CHU d'Angers, 49933 Angers cedex, France.
[Ti] Título:In vivo erosion of orthopedic screws prepared from nacre (mother of pearl).
[So] Source:Orthop Traumatol Surg Res;102(7):913-918, 2016 Nov.
[Is] ISSN:1877-0568
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Biodegradable biomaterials have been proposed to prepare orthopedic devices. Nacre is a natural aragonitic material made of calcium carbonate and is bioerodible. WORKING HYPOTHESIS: We postulated that nacre is biodegradable without provoking bone erosion and favors bone apposition. MATERIAL AND METHODS: We prepared orthopedic screws from nacre of the giant oyster Pinctada maxima. Threaded screws (3.5mm diameter) were implanted in 6 ewes in the upper tibial metaphysis (3 to 4 screws per animal). Their trajectory was transcortical and intramedullary to the opposite cortex. Animals were kept for 3months (n=2) and 6 months (n=4). They did not develop local inflammation. Before euthanasia, they received a double calcein labeling. Bone samples were analyzed by X-ray nanotomography and histology after embedding in poly(methyl methacrylate). The fractal dimension of the screw profiles (measured by the box-counting method) was used to quantify surface erosion. RESULTS: 3D nanotomography showed a gradual erosion of the threads, which was confirmed by a decreased fractal dimension. Histologically, multinucleated cells (non-osteoclastic appearance) were visible at the surface of the screws. No ruffled border was seen in these cells but they had extensions creeping in the organic matter between the aragonite tablets. Bone apposition was noted in the transcortical path of the screws with limited osteoconduction at the endosteum. Mineralization rate was increased in these zones composed of woven bone in contact with the nacre. DISCUSSION AND CONCLUSION: Screws prepared from nacre have the advantage of an in vivo resorbability by macrophage-derived cells and an osteoconductive apposition in contact with the material without triggering a local inflammatory reaction.
[Mh] Termos MeSH primário: Parafusos Ósseos
Nácar
Osseointegração
Tíbia/cirurgia
[Mh] Termos MeSH secundário: Animais
Pinctada
Ovinos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nacre)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160825
[St] Status:MEDLINE


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[PMID]:27540008
[Au] Autor:Mao LB; Gao HL; Yao HB; Liu L; Cölfen H; Liu G; Chen SM; Li SK; Yan YX; Liu YY; Yu SH
[Ad] Endereço:Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China.
[Ti] Título:Synthetic nacre by predesigned matrix-directed mineralization.
[So] Source:Science;354(6308):107-110, 2016 10 07.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Although biomimetic designs are expected to play a key role in exploring future structural materials, facile fabrication of bulk biomimetic materials under ambient conditions remains a major challenge. Here, we describe a mesoscale "assembly-and-mineralization" approach inspired by the natural process in mollusks to fabricate bulk synthetic nacre that highly resembles both the chemical composition and the hierarchical structure of natural nacre. The millimeter-thick synthetic nacre consists of alternating organic layers and aragonite platelet layers (91 weight percent) and exhibits good ultimate strength and fracture toughness. This predesigned matrix-directed mineralization method represents a rational strategy for the preparation of robust composite materials with hierarchically ordered structures, where various constituents are adaptable, including brittle and heat-labile materials.
[Mh] Termos MeSH primário: Materiais Biomiméticos/química
Biomimética/métodos
Moluscos
Nácar/química
[Mh] Termos MeSH secundário: Animais
Materiais Biomiméticos/síntese química
Calcificação Fisiológica
Carbonato de Cálcio/química
Temperatura Alta
Nácar/síntese química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Nacre); H0G9379FGK (Calcium Carbonate)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170323
[Lr] Data última revisão:
170323
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160820
[St] Status:MEDLINE



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