The Experts below are selected from a list of 504 Experts worldwide ranked by ideXlab platform
James P Simmer - One of the best experts on this subject based on the ideXlab platform.
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a dentin sialophosphoprotein mutation that partially disrupts a splice acceptor site causes type ii dentin dysplasia
Journal of Endodontics, 2008Co-Authors: Jan C C Hu, James P SimmerAbstract:The dentin sialophosphoprotein (DSPP) gene on chromosome 4q21.3 encodes the major noncollagenous protein in tooth dentin. DSPP mutations are the principal cause of dentin dysplasia type II, dentinogenesis imperfecta type II, and dentinogenesis imperfecta type III. We have identified a DSPP splice junction mutation (IVS2-6T>G) in a family with dentin dysplasia type II. The primary dentition is discolored brown with severe attrition. The mildly discolored permanent dentition has thistle-shaped Pulp chambers, Pulp Stones, and eventual Pulp obliteration. The mutation is in the sixth nucleotide from the end of intron 2, perfectly segregates with the disease phenotype, and is absent in 200 normal control chromosomes. An in vitro splicing assay shows that pre-mRNA splicing of the mutant allele generates wild-type mRNA and mRNA lacking exon 3 in approximately equal amounts. Skipping exon 3 might interfere with signal peptide cleavage, causing endoplasmic reticulum stress, and also reduce DSPP secretion, leading to haploinsufficiency.
Gong Q - One of the best experts on this subject based on the ideXlab platform.
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Association between dental Pulp Stones and calcifying nanoparticles
International journal of nanomedicine, 2011Co-Authors: Jinsheng Zeng, Fengdie Yang, Wei Zhang, Gong QAbstract:The etiology of dental Pulp Stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental Pulp tissue, and therefore investigated the link between CNPs and dental Pulp Stones. Sixty-five freshly collected dental Pulp Stones, each from a different patient, were analyzed. Thirteen of the Pulp Stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 Pulp Stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental Pulp Stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200–400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental Pulp Stones, suggesting that CNPs might play an important role in the calcification of dental Pulp.
Rode, Sigmar De Mello - One of the best experts on this subject based on the ideXlab platform.
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Estudo morfológico da polpa de molares de ratos Wistar frente a uma oclusão traumática experimental
Universidade de São Paulo. Faculdade de Odontologia, 2000Co-Authors: Penna, Luiz Alberto Plácido, Rode, Sigmar De MelloAbstract:Pulpal morphological alterations in mandibular molars of rats, resulting from an experimental external stimulus (occlusal interference), were studied using light microscopy. We placed amalgam restorations in supraocclusion in the right superior first molars of 10 Wistar rats divided into three groups, which were sacrificed by transcardiac perfusion with 10% formalin, after 10, 20 and 30 days. The evaluation of the right (experimental side) and left (control side) inferior molars was made after decalcification of the bony specimens with EDTA solution associated with microwaves, followed by routine histologic technique and staining with HE and Mallory’s Trichrome. On the control side, an intense reaction characterized by an atypical positioning of the odontoblasts was observed, followed by the appearance of Pulp Stones and, subsequently, by an apparent and uniform accommodation of the tissue in the whole Pulp, with moderate incidence of collagenous fibers. On the experimental side, the alterations were similar, but they apparently increased with time, specially after 30 days, when the histologic image was similar to that of the control side after 10 days. We can conclude that the occlusal interference induces alterations in the Pulpal connective tissue both on the experimental side and on the control side, and they are proportional to the direction of the mandibular movements.As alterações morfológicas Pulpares, decorrentes de um estímulo externo experimental (interferência oclusal), foram estudadas, em nível de microscopia de luz. Utilizaram-se restaurações de amálgama, em sobreoclusão nos primeiros molares superiores direitos de dez ratos Wistar, divididos em 3 grupos e sacrificados por perfusão transcardíaca com formol a 10%, aos 10, 20 e 30 dias. A avaliação foi feita nos molares inferiores direitos (lado experimental) e esquerdos (lado controle). As peças ósseas após descalcificação em solução de EDTA associada às microondas, seguiram técnica histológica de rotina e coloração por hematoxilina-eosina e tricrômico de Mallory. Verificou-se no lado controle uma reação intensa caracterizada por um posicionamento atípico dos odontoblastos, seguida pelo aparecimento de cálculos Pulpares e posteriormente por uma aparente e uniforme acomodação tecidual em toda a polpa, com moderada incidência de fibras colágenas. No lado experimental, as alterações foram similares parecendo, porém, aumentar com o tempo, principalmente aos 30 dias, onde a imagem histológica era semelhante à do lado controle aos 10 dias. Os resultados obtidos permitiram concluir que a interferência oclusal provocou alterações no tecido conjuntivo Pulpar tanto no lado experimental como no controle e que as mesmas foram proporcionais à direção dos movimentos mandibulares
Sigmar De Mello Rode - One of the best experts on this subject based on the ideXlab platform.
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Estudo morfológico da polpa de molares de ratos Wistar frente a uma oclusão traumática experimental Morphological study of the Pulp of Wistar rats molars under experimental occlusal interference
Universidade de São Paulo, 2000Co-Authors: Luiz Alberto Plácido Penna, Sigmar De Mello RodeAbstract:As alterações morfológicas Pulpares, decorrentes de um estímulo externo experimental (interferência oclusal), foram estudadas, em nível de microscopia de luz. Utilizaram-se restaurações de amálgama, em sobreoclusão nos primeiros molares superiores direitos de dez ratos Wistar, divididos em 3 grupos e sacrificados por perfusão transcardíaca com formol a 10%, aos 10, 20 e 30 dias. A avaliação foi feita nos molares inferiores direitos (lado experimental) e esquerdos (lado controle). As peças ósseas após descalcificação em solução de EDTA associada às microondas, seguiram técnica histológica de rotina e coloração por hematoxilina-eosina e tricrômico de Mallory. Verificou-se no lado controle uma reação intensa caracterizada por um posicionamento atípico dos odontoblastos, seguida pelo aparecimento de cálculos Pulpares e posteriormente por uma aparente e uniforme acomodação tecidual em toda a polpa, com moderada incidência de fibras colágenas. No lado experimental, as alterações foram similares parecendo, porém, aumentar com o tempo, principalmente aos 30 dias, onde a imagem histológica era semelhante à do lado controle aos 10 dias. Os resultados obtidos permitiram concluir que a interferência oclusal provocou alterações no tecido conjuntivo Pulpar tanto no lado experimental como no controle e que as mesmas foram proporcionais à direção dos movimentos mandibulares.Pulpal morphological alterations in mandibular molars of rats, resulting from an experimental external stimulus (occlusal interference), were studied using light microscopy. We placed amalgam restorations in supraocclusion in the right superior first molars of 10 Wistar rats divided into three groups, which were sacrificed by transcardiac perfusion with 10% formalin, after 10, 20 and 30 days. The evaluation of the right (experimental side) and left (control side) inferior molars was made after decalcification of the bony specimens with EDTA solution associated with microwaves, followed by routine histologic technique and staining with HE and Mallory’s Trichrome. On the control side, an intense reaction characterized by an atypical positioning of the odontoblasts was observed, followed by the appearance of Pulp Stones and, subsequently, by an apparent and uniform accommodation of the tissue in the whole Pulp, with moderate incidence of collagenous fibers. On the experimental side, the alterations were similar, but they apparently increased with time, specially after 30 days, when the histologic image was similar to that of the control side after 10 days. We can conclude that the occlusal interference induces alterations in the Pulpal connective tissue both on the experimental side and on the control side, and they are proportional to the direction of the mandibular movements
Wei Zhang - One of the best experts on this subject based on the ideXlab platform.
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Association between dental Pulp Stones and calcifying nanoparticles
International journal of nanomedicine, 2011Co-Authors: Jinsheng Zeng, Fengdie Yang, Wei Zhang, Gong QAbstract:The etiology of dental Pulp Stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental Pulp tissue, and therefore investigated the link between CNPs and dental Pulp Stones. Sixty-five freshly collected dental Pulp Stones, each from a different patient, were analyzed. Thirteen of the Pulp Stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 Pulp Stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental Pulp Stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200–400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental Pulp Stones, suggesting that CNPs might play an important role in the calcification of dental Pulp.
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Association between dental Pulp Stones and calcifying nanoparticles
Dove Medical Press, 2011Co-Authors: Jinfeng Zeng, Fang Yang, Wei ZhangAbstract:Jinfeng Zeng1*, Fang Yang1*, Wei Zhang2, Qimei Gong1, Yu Du1, Junqi Ling11Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology and Institute of Stomatological Research, Sun Yat-sen University, Guangzhou, China; 2National Neuroscience Institute, Singapore *These authors contributed equally to this workAbstract: The etiology of dental Pulp Stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental Pulp tissue, and therefore investigated the link between CNPs and dental Pulp Stones. Sixty-five freshly collected dental Pulp Stones, each from a different patient, were analyzed. Thirteen of the Pulp Stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 Pulp Stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental Pulp Stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200–400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental Pulp Stones, suggesting that CNPs might play an important role in the calcification of dental Pulp.Keywords: calcifying nanoparticles, nanobacteria, Pulp stone
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Evaluation of the interaction between calcifying nanoparticles and human dental Pulp cells: a preliminary investigation
Dove Medical Press, 2010Co-Authors: Fang Yang, Jinfeng Zeng, Wei ZhangAbstract:Fang Yang1,4, Jinfeng Zeng1,4, Wei Zhang2, Xi Sun3, Junqi Ling11Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology and Institute of Stomatological Research, Sun Yat-sen University, Guangzhou, China; 2National Neuroscience Institute, Singapore; 3School of Biological Engineering, Tianjin University of Science and Technology, Tianjin, China; 4These authors contributed equally to this workAbstract: Calcifying nanoparticles (CNPs, previously called nanobacteria) are self-propagating, cultivable macromolecular complexes. Their extraordinary characteristic is that they can aggregate carbonate apatite on their envelope from soluble calcium and phosphorus at physiologic concentrations and display cytotoxic effects on murine and human fibroblast cell lines. The question arises whether CNPs contribute to the degeneration of Pulp tissue and thus result in clinically significant human dental Pulp Stones as nidies. This study evaluates CNPs' effects upon human dental Pulp cells (HDPCs, the host cells in Pulp tissue). We observed the ultrastructural variation of HDPCs attacked by CNPs. The spatial relationship of HDPCs and CNPs after coculture was also identified by immunofluroscence staining. Furthermore, it was verified by MTT viability assay that CNPs isolated from dental Pulp Stones exerted cytotoxic effect on HDPCs. Therefore, it could be concluded that the existence of CNPs might interfere with the normal physiologic function of the cells, and that might lead to dental Pulp calcification. Elucidation of the cytotoxic characteristics of CNPs may offer a new perspective for understanding the etiology of human dental Pulp Stones.Keywords: calcifying nanoparticles, nanobacteria, human dental Pulp cell
