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Sample records for human dental tissues

  1. High resolution ultrastructure imaging of fractures in human dental tissues

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    Tan Sui

    2014-01-01

    Full Text Available Human dental hard tissues are dentine, cementum, and enamel. These are hydrated mineralised composite tissues with a hierarchical structure and versatile thermo-mechanical properties. The hierarchical structure of dentine and enamel was imaged by transmission electron microscopy (TEM of samples prepared by focused ion beam (FIB milling. High resolution TEM was carried out in the vicinity of a crack tip in dentine. An intricate “random weave” pattern of hydroxyapatile crystallites was observed and this provided a possible explanation for toughening of the mineralized dentine tissue at the nano-scale. The results reported here provide the basis for improved understanding of the relationship between the multi-scale nature and the mechanical properties of hierarchically structured biomaterials, and will also be useful for the development of better prosthetic and dental restorative materials.

  2. Characterization of Human Dental Pulp Tissue Under Oscillatory Shear and Compression.

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    Ozcan, Burak; Bayrak, Ece; Erisken, Cevat

    2016-06-01

    Availability of material as well as biological properties of native tissues is critical for biomaterial design and synthesis for regenerative engineering. Until recently, selection of biomaterials and biomolecule carriers for dental pulp regeneration has been done randomly or based on experience mainly due to the absence of benchmark data for dental pulp tissue. This study, for the first time, characterizes the linear viscoelastic material functions and compressive properties of human dental pulp tissue harvested from wisdom teeth, under oscillatory shear and compression. The results revealed a gel-like behavior of the pulp tissue over the frequency range of 0.1-100 rps. Uniaxial compression tests generated peak normal stress and compressive modulus values of 39.1 ± 20.4 kPa and 5.5 ± 2.8 kPa, respectively. Taken collectively, the linear viscoelastic and uniaxial compressive properties of the human dental pulp tissue reported here should enable the better tailoring of biomaterials or biomolecule carriers to be employed in dental pulp regeneration.

  3. Action of nitric oxide on healthy and inflamed human dental pulp tissue.

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    da Silva, Leopoldo Penteado Nucci; Issa, João Paulo Mardegan; Del Bel, Elaine Aparecida

    2008-10-01

    Irreversible pulpitis has been associated with pain and an increase in the number of pulp inflammatory cells. Based on the action of nitric oxide (NO) elsewhere, NO may possibly participate in the sensory and autonomic innervation of the dental pulp, and may influence local inflammatory responses. The purpose of this study was to analyze normal and inflamed human dental pulp for the presence of NADPH-diaphorase (NADPH-d), as an index of NO system activity. Six non-carious second premolar pulp tissue samples were obtained from young patients who required extractions for orthodontic reasons and six inflamed samples were obtained from symptomatic carious second premolars clinically diagnosed with irreversible pulpitis. Pulp tissue was carefully removed, fixed by immersion in a cold 4% PFA buffered solution for 120 min, rinsed in cold phosphate buffer, and quickly-frozen for cryostat sectioning. Pulp tissue was sectioned perpendicularly to the vertical axis of the tooth at 20 microm and processed for histochemistry. Sections of each specimen were stained with hematoxylin-eosin and other sections were subjected to histochemical NADPH-d detection. Results indicated the presence of NADPH reactivity within the pulps of both normal and carious teeth. In the normal teeth NADPH-d activity was detected in a small number of vascular endothelial cells and fibroblasts. The inflammatory response of the pulp from carious premolars was detected in connective tissue by the presence of an increased number of fibroblasts, angioblasts and collagen fibers. It was possible to determine the extent of odontoblast reactivity since the odontoblast layer was usually absent in these split-peel preparations. There were no obvious signs of stained pulpal nerve fibers. Overall NADPH-d staining was significantly more intense within inflamed pulp tissues compared to normal healthy samples (Mann-Whitney test, pfunctions of NO in human dental pulp in pathophysiological situations.

  4. X-ray scattering evaluation of ultrastructural changes in human dental tissues with thermal treatment.

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    Sandholzer, Michael A; Sui, Tan; Korsunsky, Alexander M; Walmsley, Anthony Damien; Lumley, Philip J; Landini, Gabriel

    2014-05-01

    Micro- and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat-induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400-900°C (30-min exposure, increments of 100°C). Subsequent combined small- and wide-angle X-ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8-fold) and enamel (1.4-fold), however at a smaller rate than reported earlier for bone tissue (5-10.7-fold). The results provide a structural reference for traditional X-ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature. © 2014 American Academy of Forensic Sciences.

  5. The irradiation action on human dental tissue by X-rays and electrons. A nanoindenter study

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    Fraenzel, Wolfgang [Halle-Wittenberg Univ., Halle (Germany). Dept. of Physics; Gerlach, Reinhard [Halle-Wittenberg Univ., Halle (Germany). Clinic of Radiation Therapy

    2009-07-01

    It is known that ionizing radiation is used in medicine for Roentgen diagnostics and for radiation therapy. The radiation interacts with matter, in particular with biological one, essentially by scattering, photoelectric effect, Compton effect and pair production. To what extent the biological material is changed thereby, depends on the type and the amount of radiation energy, on the dose and on the tissue constitution. In modern radiation therapy two different kinds of radiation are used: high energy X-rays and electron radiation. In the case of head-neck tumors the general practice is an irradiation with high energy X-rays with absorbed dose to water up to 70 Gy. Teeth destruction has been identified as a side effect during irradiation. In addition, damage to the salivary glands is often observed which leads to a decrease or even the complete loss of the salivary secretion (xerostomia). This study shows how the different energy and radiation types damage the tooth tissue. The effects of both, high X-ray energy and high energy electrons, on the mechanical properties hardness and elasticity of the human dental tissue are measured by the nanoindentation technique. We compare these results with the effect of the irradiation of low X-ray energy on the dental tissue. (orig.)

  6. The irradiation action on human dental tissue by X-rays and electrons. A nanoindenter study

    International Nuclear Information System (INIS)

    Fraenzel, Wolfgang; Gerlach, Reinhard

    2009-01-01

    It is known that ionizing radiation is used in medicine for Roentgen diagnostics and for radiation therapy. The radiation interacts with matter, in particular with biological one, essentially by scattering, photoelectric effect, Compton effect and pair production. To what extent the biological material is changed thereby, depends on the type and the amount of radiation energy, on the dose and on the tissue constitution. In modern radiation therapy two different kinds of radiation are used: high energy X-rays and electron radiation. In the case of head-neck tumors the general practice is an irradiation with high energy X-rays with absorbed dose to water up to 70 Gy. Teeth destruction has been identified as a side effect during irradiation. In addition, damage to the salivary glands is often observed which leads to a decrease or even the complete loss of the salivary secretion (xerostomia). This study shows how the different energy and radiation types damage the tooth tissue. The effects of both, high X-ray energy and high energy electrons, on the mechanical properties hardness and elasticity of the human dental tissue are measured by the nanoindentation technique. We compare these results with the effect of the irradiation of low X-ray energy on the dental tissue. (orig.)

  7. Isolation and Characterization of Human Dental Pulp Stem Cells from Cryopreserved Pulp Tissues Obtained from Teeth with Irreversible Pulpitis.

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    Malekfar, Azin; Valli, Kusum S; Kanafi, Mohammad Mahboob; Bhonde, Ramesh R

    2016-01-01

    Human dental pulp stem cells (DPSCs) are becoming an attractive target for therapeutic purposes because of their neural crest origin and propensity. Although DPSCs can be successfully cryopreserved, there are hardly any reports on cryopreservation of dental pulp tissues obtained from teeth diagnosed with symptomatic irreversible pulpitis during endodontic treatment and isolation and characterization of DPSCs from such cryopreserved pulp. The aim of this study was to cryopreserve the said pulp tissues to propagate and characterize isolated DPSCs. A medium consisting of 90% fetal bovine serum and 10% dimethyl sulfoxide was used for cryopreservation of pulp tissues. DPSCs were isolated from fresh and cryopreserved pulp tissues using an enzymatic method. Cell viability and proliferation were determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. DPSC migration and interaction were analyzed with the wound healing assay. Mesenchymal characteristics of DPSCs were verified by flow cytometric analysis of cell surface CD markers. The osteogenic and adipogenic potential of DPSCs was shown by von Kossa and oil red O staining methods, respectively, and the polymerase chain reaction method. We found no significant difference in CD marker expression and osteogenic and adipogenic differentiation potential of DPSCs obtained from fresh and cryopreserved dental pulp tissue. Our study shows that dental pulp can be successfully cryopreserved without losing normal characteristics and differentiation potential of their DPSCs, thus making them suitable for dental banking and future therapeutic purposes. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Influence of mechanical environment on the engineering of mineralized tissues using human dental pulp stem cells and silk fibroin scaffolds

    NARCIS (Netherlands)

    Woloszyk, A.; Holsten Dircksen, S.; Bostanci, N.; Müller, R.; Hofmann, S.; Mitsiadis, T.A.

    2015-01-01

    Teeth constitute a promising source of stem cells that can be used for tissue engineering and regenerative medicine purposes. Bone loss in the craniofacial complex due to pathological conditions and severe injuries could be treated with new materials combined with human dental pulp stem cells

  9. Microtomography evaluation of dental tissue wear surface induced by in vitro simulated chewing cycles on human and composite teeth

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    Rossella Bedini

    2012-01-01

    Full Text Available In this study a 3D microtomography display of tooth surfaces after in vitro dental wear tests has been obtained. Natural teeth have been compared with prosthetic teeth, manufactured by three different polyceramic composite materials. The prosthetic dental element samples, similar to molars, have been placed in opposition to human teeth extracted by paradontology diseases. After microtomography analysis, samples have been subjected to in vitro fatigue test cycles by servo-hydraulic mechanical testing machine. After the fatigue test, each sample has been subjected again to microtomography analysis to obtain volumetric value changes and dental wear surface images. Wear surface images were obtained by 3D reconstruction software and volumetric value changes were measured by CT analyser software. The aim of this work has been to show the potential of microtomography technique to display very clear and reliable wear surface images. Microtomography analysis methods to evaluate volumetric value changes have been used to quantify dental tissue and composite material wear.

  10. Human dental pulp stem cells derived from cryopreserved dental pulp tissues of vital extracted teeth with disease demonstrate hepatic-like differentiation.

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    Chen, Y K; Huang, Anderson H C; Chan, Anthony W S; Lin, L M

    2016-06-01

    Reviewing the literature, hepatic differentiation of human dental pulp stem cells (hDPSCs) from cryopreserved dental pulp tissues of vital extracted teeth with disease has not been studied. This study is aimed to evaluate the hypothesis that hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease could possess potential hepatic differentiation. Forty vital extracted teeth with disease recruited for hDPSCs isolation, stem cell characterization and hepatic differentiation were randomly and equally divided into group A (liquid nitrogen-stored dental pulp tissues) and group B (freshly derived dental pulp tissues). Samples of hDPSCs isolated from groups A and B but without hepatic growth factors formed negative controls. A well-differentiated hepatocellular carcinoma cell line was employed as a positive control. All the isolated hDPSCs from groups A and B showed hepatic-like differentiation with morphological change from a spindle-shaped to a polygonal shape and normal karyotype. Differentiated hDPSCs and the positive control expressed hepatic metabolic function genes and liver-specific genes. Glycogen storage of differentiated hDPSCs was noted from day 7 of differentiation-medium culture. Positive immunofluorescence staining of low-density lipoprotein and albumin was observed from day 14 of differentiation-medium culture; urea production in the medium was noted from week 6. No hepatic differentiation was observed for any of the samples of the negative controls. We not only demonstrated the feasibility of hepatic-like differentiation of hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease but also indicated that the differentiated cells possessed normal karyotype and were functionally close to normal hepatic-like cells. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro.

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    Han, Young-Jin; Kang, Young-Hoon; Shivakumar, Sarath Belame; Bharti, Dinesh; Son, Young-Bum; Choi, Yong-Ho; Park, Won-Uk; Byun, June-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-01-01

    We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro . Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro , the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro . Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.

  12. Isolation and characterization of mesenchymal stem cells derived from dental pulp and follicle tissue of human third molar tooth

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    Yadegary Z

    2011-04-01

    Full Text Available "nBackground and Aims: In the last decade, several studies have reported the isolation of stem cell population from different dental sources, while their mesenchymal nature is still controversial. The aim of this study was to isolate stem cells from mature human dental pulp and follicle and to determine their mesenchymal nature before differentiation based on the ISCT (International Society for Cellular Therapy criteria."nMaterials and Methods: In this experimental study, intact human third molars extracted due to prophylactic or orthodontic reasons were collected from patients aged 18-25. After tooth extraction, dental pulp and follicle were stored at 4°C in RPMI 1640 medium containing antibiotics. Dental pulp and follicle were prepared in a sterile condition and digested using an enzyme solution containing 4mg/ml collagenase I and dispase (ratio: 1:1. The cells were then cultivated in α-MEM medium. Passage-3 cells were analyzed by flow cytometry for the expression of CD34, CD45, CD 73, CD90 and CD105 surface markers."nResults: Dental pulp and follicle were observed to grow in colony forming units, mainly composed of a fibroblast-like cell population. Flow cytometry results showed that dental pulp and follicle are highly positive for CD73, CD90 and CD105 (mesenchymal stem cell markers and are negative for hematopoietic markers such as CD34 and CD 45."nConclusion: In this study we were able to successfully confirm that dental pulp and follicle stem cells isolated from permanent third molars have a mesenchymal nature before differentiation. Therefore, these two sources can be considered as an easy accessible source of mesenchymal stem cells for stem cell research and tissue engineering.

  13. Tissue non-specific alkaline phosphatase production by human dental pulp stromal cells is enhanced by high density cell culture.

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    Tomlinson, Matthew J; Dennis, Caitriona; Yang, Xuebin B; Kirkham, Jennifer

    2015-08-01

    The cell surface hydrolase tissue non-specific alkaline phosphatase (TNAP) (also known as MSCA-1) is used to identify a sub-population of bone marrow stromal cells (BMSCs) with high mineralising potential and is found on subsets of cells within the dental pulp. We aim to determine whether TNAP is co-expressed by human dental pulp stromal cells (hDPSCs) alongside a range of BMSC markers, whether this is an active form of the enzyme and the effects of culture duration and cell density on its expression. Cells from primary dental pulp and culture expanded hDPSCs expressed TNAP. Subsequent analyses revealed persistent TNAP expression and co-expression with BMSC markers such as CD73 and CD90. Flow cytometry and biochemical assays showed that increased culture durations and cell densities enhanced TNAP expression by hDPSCs. Arresting the hDPSC cell cycle also increased TNAP expression. These data confirm that TNAP is co-expressed by hDPSCs together with other BMSC markers and show that cell density affects TNAP expression levels. We conclude that TNAP is a potentially useful marker for hDPSC selection especially for uses in mineralised tissue regenerative therapies.

  14. The use of a DNA stabilizer in human dental tissues stored under different temperature conditions and time intervals

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    TERADA, Andrea Sayuri Silveira Dias; da SILVA, Luiz Antonio Ferreira; GALO, Rodrigo; de AZEVEDO, Aline; GERLACH, Raquel Fernanda; da SILVA, Ricardo Henrique Alves

    2014-01-01

    Objective The present study evaluated the use of a reagent to stabilize the DNA extracted from human dental tissues stored under different temperature conditions and time intervals. Material and Methods A total of 161 teeth were divided into two distinct groups: intact teeth and isolated dental pulp tissue. The samples were stored with or without the product at different time intervals and temperature. After storage, DNA extraction and genomic DNA quantification were performed using real-time PCR; the fragments of the 32 samples that represented each possible condition were analyzed to find the four pre-selected markers in STR analysis. Results The results of the quantification showed values ranging from 0.01 to 10,246.88 ng/μL of DNA. The statistical difference in the quantity of DNA was observed when the factors related to the time and temperature of storage were analyzed. In relation to the use of the specific reagent, its use was relevant in the group of intact teeth when they were at room temperature for 30 and 180 days. The analysis of the fragments in the 32 selected samples was possible irrespective of the amount of DNA, confirming that the STR analysis using an automated method yields good results. Conclusions The use of a specific reagent showed a significant difference in stabilizing DNA in samples of intact human teeth stored at room temperature for 30 and 180 days, while the results showed no justification for using the product under the other conditions tested. PMID:25141206

  15. Tooth Tissue Engineering: The Importance of Blood Products as a Supplement in Tissue Culture Medium for Human Pulp Dental Stem Cells.

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    Pisciolaro, Ricardo Luiz; Duailibi, Monica Talarico; Novo, Neil Ferreira; Juliano, Yara; Pallos, Debora; Yelick, Pamela Crotty; Vacanti, Joseph Phillip; Ferreira, Lydia Masako; Duailibi, Silvio Eduardo

    2015-11-01

    One of the goals in using cells for tissue engineering (TE) and cell therapy consists of optimizing the medium for cell culture. The present study compares three different blood product supplements for improved cell proliferation and protection against DNA damage in cultured human dental pulp stem cells for tooth TE applications. Human cells from dental pulp were first characterized as adult stem cells (ectomesenchymal mixed origin) by flow cytometry. Next, four different cell culture conditions were tested: I, supplement-free; II, supplemented with fetal bovine serum; III, allogeneic human serum; and IV, autologous human serum. Cultured cells were then characterized for cell proliferation, mineralized nodule formation, and colony-forming units (CFU) capability. After 28 days in culture, the comet assay was performed to assess possible damage in cellular DNA. Our results revealed that Protocol IV achieved higher cell proliferation than Protocol I (p = 0.0112). Protocols II and III resulted in higher cell proliferation than Protocol I, but no statistical differences were found relative to Protocol IV. The comet assay revealed less cell damage in cells cultured using Protocol IV as compared to Protocols II and III. The damage percentage observed on Protocol II was significantly higher than all other protocols. CFUs capability was highest using Protocol IV (p = 0.0018) and III, respectively, and the highest degree of mineralization was observed using Protocol IV as compared to Protocols II and III. Protocol IV resulted in significantly improved cell proliferation, and no cell damage was observed. These results demonstrate that human blood product supplements can be used as feasible supplements for culturing adult human dental stem cells.

  16. Regenerative medicine in dental and oral tissues: Dental pulp mesenchymal stem cell

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    Janti Sudiono

    2017-08-01

    Full Text Available Background. Regenerative medicine is a new therapeutic modality using cell, stem cell and tissue engineering technologies. Purpose. To describe the regenerative capacity of dental pulp mesenchymal stem cell. Review. In dentistry, stem cell and tissue engineering technologies develop incredibly and attract great interest, due to the capacity to facilitate innovation in dental material and regeneration of dental and oral tissues. Mesenchymal stem cells derived from dental pulp, periodontal ligament and dental follicle, can be isolated, cultured and differentiated into various cells, so that can be useful for regeneration of dental, nerves, periodontal and bone tissues. Tissue engineering is a technology in reconstructive biology, which utilizes mechanical, cellular, or biological mediators to facilitate regeneration or reconstruction of a particular tissue. The multipotency, high proliferation rates and accessibility, make dental pulp as an attractive source of mesenchymal stem cells for tissue regeneration. Revitalized dental pulp and continued root development is the focus of regenerative endodontic while biological techniques that can restore lost alveolar bone, periodontal ligament, and root cementum is the focus of regenerative periodontic. Conclucion. Dentin-derived morphogens such as BMP are known to be involved in the regulation of odontogenesis. The multipotency and angiogenic capacity of DPSCs as the regenerative capacity of human dentin / pulp complex indicated that dental pulp may contain progenitors that are responsible for dentin repair. The human periodontal ligament is a viable alternative source for possible primitive precursors to be used in stem cell therapy.

  17. Osteogenic Differentiation of Mesenchymal Stromal Cells: A Comparative Analysis Between Human Subcutaneous Adipose Tissue and Dental Pulp.

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    D'Alimonte, Iolanda; Mastrangelo, Filiberto; Giuliani, Patricia; Pierdomenico, Laura; Marchisio, Marco; Zuccarini, Mariachiara; Di Iorio, Patrizia; Quaresima, Raimondo; Caciagli, Francesco; Ciccarelli, Renata

    2017-06-01

    White adipose tissue is a source of mesenchymal stromal/stem cells (MSCs) that are actively studied for their possible therapeutic use in bone tissue repair/remodeling. To better appreciate the osteogenic potential of these cells, we compared some properties of MSCs from human subcutaneous adipose tissue [subcutaneous-adipose stromal cells (S-ASCs)] and dental pulp stem cell (DPSCs) of third-impacted molars, the latter representing a well-established MSC source. Both undifferentiated cell types showed similar fibroblast-like morphology and mesenchymal marker expression. However, undifferentiated S-ASCs displayed a faster doubling time coupled to greater proliferation and colony-forming ability than DPSCs. Also, the osteogenic differentiation of S-ASCs was greater than that of DPSCs, as evaluated by the higher levels of expression of early osteogenic markers Runt-related transcription factor-2 (RUNX2) and alkaline phosphatase at days 3-14 and of extracellular matrix mineralization at days 14-21. Moreover, S-ASCs showed a better colonization of the titanium scaffold. In addition, we investigated whether S-ASC osteogenic commitment was enhanced by adenosine A1 receptor (A1R) stimulation, as previously shown for DPSCs. Although A1R expression was constant during DPSC differentiation, it increased in S-ASC at day 21 from osteogenesis induction. Accordingly, A1R stimulation by the agonist 2-chloro-N 6 -cyclopentyl-adenosine, added to the cultures at each medium change, stimulated proliferation only in differentiating DPSC and enhanced the osteogenic differentiation earlier in DPSCs than in S-ASCs. These effects were counteracted by cell pretreatment with a selective A1R antagonist. Thus, our findings suggest that S-ASCs could be advantageously used in regenerative orthopedics/dentistry, and locally released or exogenously added purines may play a role in bone repair/remodeling, even though this aspect should be more thoroughly evaluated.

  18. Human Dental Pulp-Derived Cells Produce Bone-Like Tissue and Exhibit Bone Cell-Like Responsiveness to Mechanical Loading

    DEFF Research Database (Denmark)

    Kraft, David Christian Evar; Melsen, Birte; Bindslev, Dorthe Arenholt

    2010-01-01

    and characterize cell lines from human 3rd molar dental pulp tissue to determine whether human dental pulp-derived cells (DPCs) are osteogenic and responsive to mechanical loading by pulsating fluid flow (PFF) in vitro. Methods: Human DPCs used for this study were characterized by measuring proliferation....... We also assessed bone formation by DPCs on hydroxyapatite-tricalcium phosphate granules after subcutaneous implantation in mice. Results: We found that DPCs are intrinsically mechanosensitive and, like osteogenic cells, respond to PFF-induced fluid shear stress. Implantation of DPCs resulted...... remodeling in vivo, and therefore provide a promising new tool for regenerative dentistry, for example mineralized tissue engineering to restore bone defects in relation to periodontitis, periimplantatis and orofacial surgery. Experiments in progress have proven that DPCSs are also useful for assessing...

  19. Tissue Engineering in Regenerative Dental Therapy

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    Hiral Jhaveri-Desai

    2011-01-01

    Full Text Available Tissue engineering is amongst the latest exciting technologies having impacted the field of dentistry. Initially considered as a futuristic approach, tissue engineering is now being successfully applied in regenerative surgery. This article reviews the important determinants of tissue engineering and how they contribute to the improvement of wound healing and surgical outcomes in the oral region. Furthermore, we shall address the clinical applications of engineering involving oral and maxillofacial surgical and periodontal procedures along with other concepts that are still in experimental phase of development. This knowledge will aid the surgical and engineering researchers to comprehend the collaboration between these fields leading to extounding dental applications and to ever-continuing man-made miracles in the field of human science.

  20. Investigation of the structure of human dental tissue at multiple length scales using high energy synchrotron X-ray SAXS/WAXS

    Science.gov (United States)

    Sui, Tan; Landini, Gabriel; Korsunsky, Alexander M.

    2011-10-01

    High energy (>50keV) synchrotron X-ray scattering experiments were carried out on beamline I12 JEEP at the Diamond Light Source (DLS, Oxford, UK). Although a complete human tooth could be studied, in the present study attention was focused on coupons from the region of the Dentin-Enamel Junction (DEJ). Simultaneous high energy SAXS/WAXS measurements were carried out. Quantitative analysis of the results allows multiple length scale characterization of the nano-crystalline structure of dental tissues. SAXS patterns analysis provide insight into the mean thickness and orientation of hydroxyapatite particles, while WAXS (XRD) patterns allow the determination of the crystallographic unit cell parameters of the hydroxyapatite phase. It was found that the average particle thickness determined from SAXS interpretation varies as a function of position in the vicinity of the DEJ. Most mineral particles are randomly orientated within dentin, although preferred orientation emerges and becomes stronger on approach to the enamel. Within the enamel, texture is stronger than anywhere in the dentin, and the determination of lattice parameters can be accomplished by Pawley refinement of the multiple peak diffraction pattern. The results demonstrate the feasibility of using high energy synchrotron X-ray beams for the characterization of human dental tissues. This opens up the opportunity of studying thick samples (e.g., complete teeth) in complex sample environments (e.g., under saline solution). This opens new avenues for the application of high energy synchrotron X-ray scattering to dental research.

  1. Wnt and BMP signaling crosstalk in regulating dental stem cells: Implications in dental tissue engineering

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    Fugui Zhang

    2016-12-01

    Full Text Available Tooth is a complex hard tissue organ and consists of multiple cell types that are regulated by important signaling pathways such as Wnt and BMP signaling. Serious injuries and/or loss of tooth or periodontal tissues may significantly impact aesthetic appearance, essential oral functions and the quality of life. Regenerative dentistry holds great promise in treating oral/dental disorders. The past decade has witnessed a rapid expansion of our understanding of the biological features of dental stem cells, along with the signaling mechanisms governing stem cell self-renewal and differentiation. In this review, we first summarize the biological characteristics of seven types of dental stem cells, including dental pulp stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, periodontal ligament stem cells, alveolar bone-derived mesenchymal stem cells (MSCs, and MSCs from gingiva. We then focus on how these stem cells are regulated by bone morphogenetic protein (BMP and/or Wnt signaling by examining the interplays between these pathways. Lastly, we analyze the current status of dental tissue engineering strategies that utilize oral/dental stem cells by harnessing the interplays between BMP and Wnt pathways. We also highlight the challenges that must be addressed before the dental stem cells may reach any clinical applications. Thus, we can expect to witness significant progresses to be made in regenerative dentistry in the coming decade.

  2. Dental tissue as a thermoluminescence dosimetry dosimeter

    International Nuclear Information System (INIS)

    Solaimani, F.; Zahmatkesh, M.H.; Akhlaghpoor, Sh.

    2003-01-01

    Background: Thermoluminescence dosimetry is one of the dosimetry procedures used widely as routine and personal dosimeters. In order to extend this kind of dosimeters, dental tissue has been examined and was found promising as a Thermoluminescence Dosimetry dosimeter. Materials and Methods: In this study, 70 health teeth were collected. The only criterion, wich was considered for selection of the teeth, was the healthiness of them regardless of age and gender of the donors. All collected samples were washed and cleaned and milled uniformly. The final powder had a uniform grain size between 100-300 micrometer. The sample was divided into four groups. Group A and B were used for measurement of density and investigation of variation of thermoluminescent characteristics with temperature respectively. Groups C and D were used for investigation of variation of thermoluminescent intensity with dose and fading of this intensity with time. In all cases the results obtained with dental tissue were compared to a standard LiF, thermoluminescence dosimetry dosimeter. Results: It was found that, average density of the dental tissue was 1.570 g/cm 3 , which is comparable to density of LiF, which is 1.612g/cm 3 . It was also concluded that the range of 0-300 d ig C , dental tissue has a simple curve with two specific peaks at 140 and 25 d ig C respectively. The experiment also showed that, the variation of relative intensity versus dose is linear in the range of 0.04-0.1 Gy. The fading rate of dental tissue is higher than LiF but still in the acceptable range (14% per month in compare to 5.2% per month). Conclusion: Dental tissue as a natural dosimeter is comparable with Thermoluminescence Dosimetry and can be used in accidental events with a good approximation

  3. Nanomaterials for Craniofacial and Dental Tissue Engineering.

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    Li, G; Zhou, T; Lin, S; Shi, S; Lin, Y

    2017-07-01

    Tissue engineering shows great potential as a future treatment for the craniofacial and dental defects caused by trauma, tumor, and other diseases. Due to the biomimetic features and excellent physiochemical properties, nanomaterials are of vital importance in promoting cell growth and stimulating tissue regeneration in tissue engineering. For craniofacial and dental tissue engineering, the frequently used nanomaterials include nanoparticles, nanofibers, nanotubes, and nanosheets. Nanofibers are attractive for cell invasion and proliferation because of their resemblance to extracellular matrix and the presence of large pores, and they have been used as scaffolds in bone, cartilage, and tooth regeneration. Nanotubes and nanoparticles improve the mechanical and chemical properties of scaffold, increase cell attachment and migration, and facilitate tissue regeneration. In addition, nanofibers and nanoparticles are also used as a delivery system to carry the bioactive agent in bone and tooth regeneration, have better control of the release speed of agent upon degradation of the matrix, and promote tissue regeneration. Although applications of nanomaterials in tissue engineering remain in their infancy with numerous challenges to face, the current results indicate that nanomaterials have massive potential in craniofacial and dental tissue engineering.

  4. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

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    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B.; Wolfs, Esther; Lambrichts, Ivo

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair. PMID:27688777

  5. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Jessica Ratajczak

    2016-01-01

    Full Text Available Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair.

  6. Inhibition of odontogenic differentiation of human dental pulp cells by dental resin monomers

    OpenAIRE

    Kwon, Ji Hyun; Park, Hee Chul; Zhu, Tingting; Yang, Hyeong-Cheol

    2015-01-01

    Background Dental resin monomers that are leached from the resin matrix due to incomplete polymerization can affect the viability and various functions of oral tissues and cells. In this study, the effects of triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) on odontogenic differentiation of human dental pulp cells (HDPCs) were examined. To mimic clinical situations, dental pulp cells were treated with resin monomers for 24?h prior to the analysis of alkaline p...

  7. Influence of the mechanical environment on the engineering of mineralised tissues using human dental pulp stem cells and silk fibroin scaffolds.

    Directory of Open Access Journals (Sweden)

    Anna Woloszyk

    Full Text Available Teeth constitute a promising source of stem cells that can be used for tissue engineering and regenerative medicine purposes. Bone loss in the craniofacial complex due to pathological conditions and severe injuries could be treated with new materials combined with human dental pulp stem cells (hDPSCs that have the same embryonic origin as craniofacial bones. Optimising combinations of scaffolds, cells, growth factors and culture conditions still remains a great challenge. In the present study, we evaluate the mineralisation potential of hDPSCs seeded on porous silk fibroin scaffolds in a mechanically dynamic environment provided by spinner flask bioreactors. Cell-seeded scaffolds were cultured in either standard or osteogenic media in both static and dynamic conditions for 47 days. Histological analysis and micro-computed tomography of the samples showed low levels of mineralisation when samples were cultured in static conditions (0.16±0.1 BV/TV%, while their culture in a dynamic environment with osteogenic medium and weekly µCT scans (4.9±1.6 BV/TV% significantly increased the formation of homogeneously mineralised structures, which was also confirmed by the elevated calcium levels (4.5±1.0 vs. 8.8±1.7 mg/mL. Molecular analysis of the samples showed that the expression of tooth correlated genes such as Dentin Sialophosphoprotein and Nestin were downregulated by a factor of 6.7 and 7.4, respectively, in hDPSCs when cultured in presence of osteogenic medium. This finding indicates that hDPSCs are able to adopt a non-dental identity by changing the culture conditions only. Also an increased expression of Osteocalcin (1.4x and Collagen type I (1.7x was found after culture under mechanically dynamic conditions in control medium. In conclusion, the combination of hDPSCs and silk scaffolds cultured under mechanical loading in spinner flask bioreactors could offer a novel and promising approach for bone tissue engineering where appropriate and

  8. Influence of the mechanical environment on the engineering of mineralised tissues using human dental pulp stem cells and silk fibroin scaffolds.

    Science.gov (United States)

    Woloszyk, Anna; Holsten Dircksen, Sabrina; Bostanci, Nagihan; Müller, Ralph; Hofmann, Sandra; Mitsiadis, Thimios A

    2014-01-01

    Teeth constitute a promising source of stem cells that can be used for tissue engineering and regenerative medicine purposes. Bone loss in the craniofacial complex due to pathological conditions and severe injuries could be treated with new materials combined with human dental pulp stem cells (hDPSCs) that have the same embryonic origin as craniofacial bones. Optimising combinations of scaffolds, cells, growth factors and culture conditions still remains a great challenge. In the present study, we evaluate the mineralisation potential of hDPSCs seeded on porous silk fibroin scaffolds in a mechanically dynamic environment provided by spinner flask bioreactors. Cell-seeded scaffolds were cultured in either standard or osteogenic media in both static and dynamic conditions for 47 days. Histological analysis and micro-computed tomography of the samples showed low levels of mineralisation when samples were cultured in static conditions (0.16±0.1 BV/TV%), while their culture in a dynamic environment with osteogenic medium and weekly µCT scans (4.9±1.6 BV/TV%) significantly increased the formation of homogeneously mineralised structures, which was also confirmed by the elevated calcium levels (4.5±1.0 vs. 8.8±1.7 mg/mL). Molecular analysis of the samples showed that the expression of tooth correlated genes such as Dentin Sialophosphoprotein and Nestin were downregulated by a factor of 6.7 and 7.4, respectively, in hDPSCs when cultured in presence of osteogenic medium. This finding indicates that hDPSCs are able to adopt a non-dental identity by changing the culture conditions only. Also an increased expression of Osteocalcin (1.4x) and Collagen type I (1.7x) was found after culture under mechanically dynamic conditions in control medium. In conclusion, the combination of hDPSCs and silk scaffolds cultured under mechanical loading in spinner flask bioreactors could offer a novel and promising approach for bone tissue engineering where appropriate and rapid bone

  9. Denitrification in human dental plaque

    Directory of Open Access Journals (Sweden)

    Verstraete Willy

    2010-03-01

    Full Text Available Abstract Background Microbial denitrification is not considered important in human-associated microbial communities. Accordingly, metabolic investigations of the microbial biofilm communities of human dental plaque have focused on aerobic respiration and acid fermentation of carbohydrates, even though it is known that the oral habitat is constantly exposed to nitrate (NO3- concentrations in the millimolar range and that dental plaque houses bacteria that can reduce this NO3- to nitrite (NO2-. Results We show that dental plaque mediates denitrification of NO3- to nitric oxide (NO, nitrous oxide (N2O, and dinitrogen (N2 using microsensor measurements, 15N isotopic labelling and molecular detection of denitrification genes. In vivo N2O accumulation rates in the mouth depended on the presence of dental plaque and on salivary NO3- concentrations. NO and N2O production by denitrification occurred under aerobic conditions and was regulated by plaque pH. Conclusions Increases of NO concentrations were in the range of effective concentrations for NO signalling to human host cells and, thus, may locally affect blood flow, signalling between nerves and inflammatory processes in the gum. This is specifically significant for the understanding of periodontal diseases, where NO has been shown to play a key role, but where gingival cells are believed to be the only source of NO. More generally, this study establishes denitrification by human-associated microbial communities as a significant metabolic pathway which, due to concurrent NO formation, provides a basis for symbiotic interactions.

  10. Heat generation caused by ablation of dental hard tissues with an ultrashort pulse laser (USPL) system.

    Science.gov (United States)

    Braun, Andreas; Krillke, Raphael Franz; Frentzen, Matthias; Bourauel, Christoph; Stark, Helmut; Schelle, Florian

    2015-02-01

    Heat generation during the removal of dental hard tissues may lead to a temperature increase and cause painful sensations or damage dental tissues. The aim of this study was to assess heat generation in dental hard tissues following laser ablation using an ultrashort pulse laser (USPL) system. A total of 85 specimens of dental hard tissues were used, comprising 45 specimens of human dentine evaluating a thickness of 1, 2, and 3 mm (15 samples each) and 40 specimens of human enamel with a thickness of 1 and 2 mm (20 samples each). Ablation was performed with an Nd:YVO4 laser at 1,064 nm, a pulse duration of 9 ps, and a repetition rate of 500 kHz with an average output power of 6 W. Specimens were irradiated for 0.8 s. Employing a scanner system, rectangular cavities of 1-mm edge length were generated. A temperature sensor was placed at the back of the specimens, recording the temperature during the ablation process. All measurements were made employing a heat-conductive paste without any additional cooling or spray. Heat generation during laser ablation depended on the dental hard tissue (enamel or dentine) and the thickness of the respective tissue (p dental hard tissues, heat generation has to be considered. Especially during laser ablation next to pulpal tissues, painful sensations and potential thermal injury of pulp tissue might occur.

  11. The CuHBr laser in hard dental tissues

    International Nuclear Information System (INIS)

    Miyakawa, Walter

    2004-01-01

    In this work, it was verified the viability of characterization of laser-irradiated dental tissues in two extreme conditions: high and low absorption by the dental tissue. Comparison with light microscopy and scanning electronic microscopy revealed that these techniques are complementary each other: quantitative topographic information is directly extracted from the atomic force microscopy, while morphological aspects can be imaged by light microscopy or scanning electronic microscopy. A cavity generated by Cu-HyBrID laser in human dental enamel was also evaluated by atomic force microscopy. Structural and morphological differences between the fused and resolidified enamel from the cavity walls and the enamel from the natural tis sue were analyzed. A model, based on the Monte Carlo method described the propagation of CuHBr laser radiation and the absorbed energy distribution in dental tissues. Experimental measures with a CCD camera were used to semiquantitatively characterize the scattered light distribution in the tooth and they corroborated the model. It was observed that Rayleigh scattering and diffuse scattered radiation is predominant. The absorbed energy distribution map and the temperature variation along the beam propagation axis presented strong dependence with the absorption coefficient of the dental enamel and they cannot be deduced from the light distribution profile. The exposure time threshold for dental enamel melting and evaporation, irradiated by a specific condition of the green line of the Cu-HyBrID laser, was determined and a phenomenological model was discussed for the laser-matter interaction, based on pulse accumulation effect. Theoretical temperature calculations associated with experimental evidences strongly suggest that optical and thermal parameters should vary with temperature. The obtained exposure time threshold should correspond to the time necessary to the sample reach the critical temperature, at which the increase of absorption

  12. Dental Calculus and the Evolution of the Human Oral Microbiome.

    Science.gov (United States)

    Warinner, Christina

    2016-07-01

    Characterizing the evolution of the oral microbiome is a challenging, but increasingly feasible, task. Recently, dental calculus has been shown to preserve ancient biomolecules from the oral microbiota, host tissues and diet for tens of thousands of years. As such, it provides a unique window into the ancestral oral microbiome. This article reviews recent advancements in ancient dental calculus research and emerging insights into the evolution and ecology of the human oral microbiome.

  13. Human dental pulp stem cells: Applications in future regenerative medicine

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-01-01

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine. PMID:26131314

  14. Hard and soft tissue surgical complications in dental implantology.

    Science.gov (United States)

    Aziz, Shahid R

    2015-05-01

    This article discusses surgical complications associated with the placement of dental implants, specifically focusing on how they occur (etiology), as well as their management and prevention. Dental implant surgical complications can be classified into those of hard and soft tissues. In general, complications can be avoided with thorough preoperative treatment planning and proper surgical technique. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Effect of miR-146a/bFGF/PEG-PEI Nanoparticles on Inflammation Response and Tissue Regeneration of Human Dental Pulp Cells

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2016-01-01

    Full Text Available Introduction. Inflammation in dental pulp cells (DPCs initiated by Lipopolysaccharide (LPS results in dental pulp necrosis. So far, whether there is a common system regulating inflammation response and tissue regeneration remains unknown. miR-146a is closely related to inflammation. Basic fibroblast growth factor (bFGF is an important regulator for differentiation. Methods. To explore the effect of miR-146a/bFGF on inflammation and tissue regeneration, polyethylene glycol-polyethyleneimine (PEG-PEI was synthesized, and physical characteristics were analyzed by dynamic light scattering and gel retardation analysis. Cell absorption, transfection efficiency, and cytotoxicity were assessed. Alginate gel was combined with miR-146a/PEG-PEI nanoparticles and bFGF. Drug release ratio was measured by ultraviolet spectrophotography. Proliferation and odontogenic differentiation of DPCs with 1 μg/mL LPS treatment were determined. Results. PEG-PEI prepared at N/P 2 showed complete gel retardation and smallest particle size and zeta potential. Transfection efficiency of PEG-PEI was higher than lipo2000. Cell viability decreased as N/P ratio increased. Drug release rate amounted to 70% at the first 12 h and then maintained slow release afterwards. Proliferation and differentiation decreased in DPCs with LPS treatment, whereas they increased in miR-146a/bFGF gel group. Conclusions. PEG-PEI is a promising vector for gene therapy. miR-146a and bFGF play critical roles in inflammation response and tissue regeneration of DPCs.

  16. Extracellular matrix of dental pulp stem cells: Applications in pulp tissue engineering using somatic MSCs

    Directory of Open Access Journals (Sweden)

    Sriram eRavindran

    2014-01-01

    Full Text Available Dental Caries affects approximately 90% of the world’s population. At present, the clinical treatment for dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality. Tissue engineering can potentially solve this problem by enabling regeneration of a functional pulp tissue. Dental pulp stem cells (DPSCs have been shown to be an excellent source for pulp regeneration. However, limited availability of these cells hinders its potential for clinical translation. We have investigated the possibility of using somatic mesenchymal stem cells from other sources for dental pulp tissue regeneration using a biomimetic dental pulp extracellular matrix (ECM incorporated scaffold. Human periodontal ligament stem cells (PDLSCs and human bone marrow stromal cells (HMSCs were investigated for their ability to differentiate towards an odontogenic lineage. In vitro real-time PCR results coupled with histological and immunohistochemical examination of the explanted tissues confirmed the ability of PDLSCs and HMSCs to form a vascularized pulp-like tissue. These findings indicate that the dental pulp stem derived ECM scaffold stimulated odontogenic differentiation of PDLSCs and HMSCs without the need for exogenous addition of growth and differentiation factors. This study represents a translational perspective toward possible therapeutic application of using a combination of somatic stem cells and extracellular matrix for pulp regeneration.

  17. Dental Tissue — New Source for Stem Cells

    Directory of Open Access Journals (Sweden)

    Vladimir Petrovic

    2009-01-01

    Full Text Available Stem cells have been isolated from many tissues and organs, including dental tissue. Five types of dental stem cells have been established: dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, periodontal ligament stem cells, and dental follicle progenitor cells. The main characteristics of dental stem cells are their potential for multilineage differentiation and self-renewal capacity. Dental stem cells can differentiate into odontoblasts, adipocytes, neuronal-like cells, glial cells, osteoblasts, chondrocytes, melanocytes, myotubes, and endothelial cells. Possible application of these cells in various fields of medicine makes them good candidates for future research as a new, powerful tool for therapy. Although the possible use of these cells in therapeutic purposes and tooth tissue engineering is still in the beginning stages, the results are promising. The efforts made in the research of dental stem cells have clarified many mechanisms underlying the biological processes in which these cells are involved. This review will focus on the new findings in the field of dental stem cell research and on their potential use in the therapy of various disorders.

  18. DENTAL PULP STEM CELLS AND HUMAN PERIAPICAL CYST MESENCHYMAL STEM CELLS IN BONE TISSUE REGENERATION: COMPARISON OF BASAL AND OSTEOGENIC DIFFERENTIATED GENE EXPRESSION OF A NEWLY DISCOVERED MESENCHYMAL STEM CELL LINEAGE.

    Science.gov (United States)

    Tatullo, M; Falisi, G; Amantea, M; Rastelli, C; Paduano, F; Marrelli, M

    2015-01-01

    Bone regeneration is an interesting field of biomedicine. The most recent studies are aimed to achieve a bone regeneration using mesenchymal stem cells (MSCs) taken from more accessible sites: oral and dental tissues have been widely investigated as a rich accessible source of MSCs. Dental Pulp Stem Cells (DPSCs) and human Periapical Cysts Mesenchymal Stem Cells (hPCy-MSCs) represent the new generation MSCs. The aim of this study is to compare the gene expression of these two innovative cell types to highlight the advantages of their use in bone regeneration. The harvesting, culturing and differentiating of cells isolated from dental pulp as well as from periapical cystic tissue were carried out as described in previously published reports. qRT-PCR analyses were performed on osteogenic genes in undifferentiated and osteogenic differentiated cells of DPSC and hPCy-MSC lineage. Real-time RT-PCR data suggested that both DPSCs and hPCy-MSCs cultured in osteogenic media are able to differentiate into osteoblast/odontoblast-like cells: however, some differences indicated that DPSCs seem to be directed more towards dentinogenesis, while hPCy-MSCs seem to be directed more towards osteogenesis.

  19. Nigerian dental technology students and human immunodeficiency ...

    African Journals Online (AJOL)

    Background: The rehabilitative dental care is important for maintaining adequate nutrition, guarding against wasting syndrome and malnutrition among human immunodeficiency virus (HIV)‑infected individuals. Aim: The aim of this study is to determine the Nigerian dental technology students' knowledge and ...

  20. Biomechanical study of the bone tissue with dental implants interaction

    Directory of Open Access Journals (Sweden)

    Navrátil P.

    2011-12-01

    Full Text Available The article deals with the stress-strain analysis of human mandible in the physiological state and after the dental implant application. The evaluation is focused on assessing of the cancellous bone tissue modeling-level. Three cancellous bone model-types are assessed: Non-trabecular model with homogenous isotropic material, nontrabecular model with inhomogeneous material obtained from computer tomography data using CT Data Analysis software, and trabecular model built from mandible section image. Computational modeling was chosen as the most suitable solution method and the solution on two-dimensional level was carried out. The results show that strain is more preferable value than stress in case of evaluation of mechanical response in cancellous bone. The non-trabecular model with CT-obtained material model is not acceptable for stress-strain analysis of the cancellous bone for singularities occurring on interfaces of regions with different values of modulus of elasticity.

  1. Bioengineering of Dental Tissues: Bibliometric Analysis 2000-2011.

    Directory of Open Access Journals (Sweden)

    Sebastián Zamorano

    2014-03-01

    Full Text Available Introduction: There has been a noticeable increase in experimental use and therapies based on stem cells over recent years. Nevertheless, there is a lack of information about this progress in the dental field, which makes it difficult to trace development and design policies. The purpose of this study, as a first approach to the subject, is to determine a bibliometric profile for the investigation related to bioengineering of dental tissue at a worldwide scale, based on the MEDLINE database, for the period 2000-2011. Methodology: A bibliometric study was carried out. Every article indexed in the MEDLINE database and associated with the terms “stem cells” and “tooth regeneration” for the period 2000-2011 was included. The analyzed variables were publishing date, country of origin, language and publication type (original or review, journal, author, associated university and tissue source (human or animal. Results: For the entire period included in the study, 257 articles were found. Of these, 149 corresponded to original Works published in English; 5 in other languages; 92 comprised literature reviews in English, 9 in other languages and 2 publications were included in the “others” category. The countries with the highest research productivity were the United States (24.51%, Japan (20.62% and China (17.90%, while Brazil (3.9% was the only Latin-American country found in the list. Animal tissues were used in 59.09% of them. The most productive authors were Ueda M (17 and Jin Y (11, whereas Fourth Military University (13, University of Tokyo (12 and Capital Medical University (10 had the largest number of publications. Conclusion: The United States, Japan and China concentrate about two thirds of the production. Latin-America was represented only by Brazil.

  2. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    Directory of Open Access Journals (Sweden)

    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  3. A hyaluronan-based scaffold for the in vitro construction of dental pulp-like tissue.

    Science.gov (United States)

    Ferroni, Letizia; Gardin, Chiara; Sivolella, Stefano; Brunello, Giulia; Berengo, Mario; Piattelli, Adriano; Bressan, Eriberto; Zavan, Barbara

    2015-03-02

    Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D) hyaluronan scaffold and human dental pulp stem cells (DPSCs) to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF) staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  4. Dental hard tissue characterization using laser-based ultrasonics

    Science.gov (United States)

    Blodgett, David W.; Massey, Ward L.

    2003-07-01

    Dental health care and research workers require a means of imaging the structures within teeth in vivo. One critical need is the detection of tooth decay in its early stages. If decay can be detected early enough, the process can be monitored and interventional procedures, such as fluoride washes and controlled diet, can be initiated to help re-mineralize the tooth. Currently employed x-ray imaging is limited in its ability to visualize interfaces and incapable of detecting decay at a stage early enough to avoid invasive cavity preparation followed by a restoration. To this end, non-destructive and non-contact in vitro measurements on extracted human molars using laser-based ultrasonics are presented. Broadband ultrasonic waves are excited in the extracted sections by using a pulsed carbon-dioxide (CO2) laser operating in a region of high optical absorption in the dental hard tissues. Optical interferometric detection of the ultrasonic wave surface displacements in accomplished with a path-stabilized Michelson-type interferometer. Results for bulk and surface in-vitro characterization of caries are presented on extracted molars with pre-existing caries.

  5. Dental hard tissue drilling by longitudinally excited CO2 laser

    Science.gov (United States)

    Uno, Kazuyuki; Yamamoto, Takuya; Akitsu, Tetsuya; Jitsuno, Takahisa

    2017-07-01

    We developed a longitudinally excited CO2 laser with a long optical cavity and investigated the drilling characteristics of dental hard tissue. The CO2 laser was very simple and consisted of a 45-cm-long alumina ceramic pipe with an inner diameter of 13 mm, a pulse power supply, a step-up transformer, a storage capacitance, a spark gap, and a long optical cavity with a cavity length of 175 cm. The CO2 laser produced a short pulse that had a spike pulse with the width of 337 ns and the energy of 1.9 mJ, a pulse tail with the length of 180 μs and the energy of 37.6 mJ, and a doughnut-like beam. In the investigation, a sample was a natural drying human tooth (enamel and dentine). In a processing system, a ZnSe focusing lens with the focal length of 50 mm was used and the location of the focal plane was that of the sample surface. In 1 pulse irradiation, the drilling characteristics depended on the fluence was investigated. In the enamel and dentin drilling, the drilling depth increased with the fluence. The 1 pulse irradiation with the fluence of 21.5 J/cm2 produced the depth of 79.3 μm in the enamel drilling, and the depth of 152.7 μm in the dentin drilling. The short-pulse CO2 laser produced a deeper drilling depth at a lower fluence than long-pulse CO2 lasers in dental hard tissue processing.

  6. Lack of cytotoxicity by Trustwater Ecasol™ used to maintain good quality dental unit waterline output water in keratinocyte monolayer and reconstituted human oral epithelial tissue models.

    LENUS (Irish Health Repository)

    Boyle, M A

    2010-11-01

    We previously showed that residual treatment of dental chair unit (DCU) supply water using the electrochemically-activated solution Trustwater Ecasol™ (2.5 ppm) provided an effective long-term solution to the problem of dental unit waterline (DUWL) biofilm resulting in DUWL output water quality consistently superior to potable water.

  7. [Human brown adipose tissue].

    Science.gov (United States)

    Virtanen, Kirsi A; Nuutila, Pirjo

    2015-01-01

    Adult humans have heat-producing and energy-consuming brown adipose tissue in the clavicular region of the neck. There are two types of brown adipose cells, the so-called classic and beige adipose cells. Brown adipose cells produce heat by means of uncoupler protein 1 (UCP1) from fatty acids and sugar. By applying positron emission tomography (PET) measuring the utilization of sugar, the metabolism of brown fat has been shown to multiply in the cold, presumably influencing energy consumption. Active brown fat is most likely present in young adults, persons of normal weight and women, least likely in obese persons.

  8. Pulp and periodontal tissue repair - regeneration or tissue metaplasia after dental trauma. A review

    DEFF Research Database (Denmark)

    Andreasen, Jens O

    2012-01-01

    Healing subsequent to dental trauma is known to be very complex, a result explained by the variability of the types of dental trauma (six luxations, nine fracture types, and their combinations). On top of that, at least 16 different cellular systems get involved in more severe trauma types each o...... of tissue replaces the injured). In this study, a review is given of the impact of trauma to various dental tissues such as alveolar bone, periodontal ligament, cementum, Hertvigs epithelial root sheath, and the pulp....... of them with a different potential for healing with repair, i.e. (re-establishment of tissue continuity without functional restitution) and regeneration (where the injured or lost tissue is replaced with new tissue with identical tissue anatomy and function) and finally metaplasia (where a new type...

  9. Secretoneurin and PE-11 immunoreactivity in the human dental pulp.

    Science.gov (United States)

    Steiner, René; Fischer-Colbrie, Reiner; Bletsa, Athanasia; Laimer, Johannes; Troger, Josef

    2018-02-01

    To explore whether there are differences in the concentration of the secretogranin II-derived peptide secretoneurin and the chromogranin B-derived peptide PE-11 between the healthy and inflamed human dental pulps. Furthermore, colocalization studies with calcitonin gene-related peptide were performed to confirm the sensory origin of the peptidergic nerves in the dental pulp. The concentrations of secretoneurin and PE-11 were determined by highly sensitive radioimmunoassays in extracts of dental pulps, the molecular form of secretoneurin immunoreactivities by RP-HPLC with subsequent radioimmunoassay and colocalization studies with calcitonin gene-related peptide were performed by double immunofluorescence. Only secretoneurin but not PE-11 was detectable by radioimmunoassays whereas nerve fibers could be made visible for both secretoneurin and PE-11. Furthermore, there was a full colocalization of secretoneurin and PE-11 with calcitonin gene-related peptide in immunohistochemical experiments. There were no differences in the concentration of secretoneurin between the healthy and inflamed human dental pulp and moreover, the characterization of the secretoneurin immunoreactivities revealed that only authentic secretoneurin was detected with the secretoneurin antibody. There is unequivocal evidence that secretoneurin and PE-11 are constituents of the sensory innervation of the human dental pulp and although not exclusively but are yet present in unmyelinated C-fibers which transmit predominantly nociceptive impulses. Secretoneurin might be involved in local effector functions as well, particularly in neurogenic inflammation, given that this is the case despite of unaltered levels in inflamed tissue. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Soft tissue wound healing around teeth and dental implants.

    Science.gov (United States)

    Sculean, Anton; Gruber, Reinhard; Bosshardt, Dieter D

    2014-04-01

    To provide an overview on the biology and soft tissue wound healing around teeth and dental implants. This narrative review focuses on cell biology and histology of soft tissue wounds around natural teeth and dental implants. The available data indicate that: (a) Oral wounds follow a similar pattern. (b) The tissue specificities of the gingival, alveolar and palatal mucosa appear to be innately and not necessarily functionally determined. (c) The granulation tissue originating from the periodontal ligament or from connective tissue originally covered by keratinized epithelium has the potential to induce keratinization. However, it also appears that deep palatal connective tissue may not have the same potential to induce keratinization as the palatal connective tissue originating from an immediately subepithelial area. (d) Epithelial healing following non-surgical and surgical periodontal therapy appears to be completed after a period of 7–14 days. Structural integrity of a maturing wound between a denuded root surface and a soft tissue flap is achieved at approximately 14-days post-surgery. (e) The formation of the biological width and maturation of the barrier function around transmucosal implants requires 6–8 weeks of healing. (f) The established peri-implant soft connective tissue resembles a scar tissue in composition, fibre orientation, and vasculature. (g) The peri-implant junctional epithelium may reach a greater final length under certain conditions such as implants placed into fresh extraction sockets versus conventional implant procedures in healed sites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Purified Human Dental Pulp Stem Cells Promote Osteogenic Regeneration.

    Science.gov (United States)

    Yasui, T; Mabuchi, Y; Toriumi, H; Ebine, T; Niibe, K; Houlihan, D D; Morikawa, S; Onizawa, K; Kawana, H; Akazawa, C; Suzuki, N; Nakagawa, T; Okano, H; Matsuzaki, Y

    2016-02-01

    Human dental pulp stem/progenitor cells (hDPSCs) are attractive candidates for regenerative therapy because they can be easily expanded to generate colony-forming unit-fibroblasts (CFU-Fs) on plastic and the large cell numbers required for transplantation. However, isolation based on adherence to plastic inevitably changes the surface marker expression and biological properties of the cells. Consequently, little is currently known about the original phenotypes of tissue precursor cells that give rise to plastic-adherent CFU-Fs. To better understand the in vivo functions and translational therapeutic potential of hDPSCs and other stem cells, selective cell markers must be identified in the progenitor cells. Here, we identified a dental pulp tissue-specific cell population based on the expression profiles of 2 cell-surface markers LNGFR (CD271) and THY-1 (CD90). Prospectively isolated, dental pulp-derived LNGFR(Low+)THY-1(High+) cells represent a highly enriched population of clonogenic cells--notably, the isolated cells exhibited long-term proliferation and multilineage differentiation potential in vitro. The cells also expressed known mesenchymal cell markers and promoted new bone formation to heal critical-size calvarial defects in vivo. These findings suggest that LNGFR(Low+)THY-1(High+) dental pulp-derived cells provide an excellent source of material for bone regenerative strategies. © International & American Associations for Dental Research 2015.

  12. Automated classification and visualization of healthy and pathological dental tissues based on near-infrared hyper-spectral imaging

    Science.gov (United States)

    Usenik, Peter; Bürmen, Miran; Vrtovec, Tomaž; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2011-03-01

    Despite major improvements in dental healthcare and technology, dental caries remains one of the most prevalent chronic diseases of modern society. The initial stages of dental caries are characterized by demineralization of enamel crystals, commonly known as white spots which are difficult to diagnose. If detected early enough, such demineralization can be arrested and reversed by non-surgical means through well established dental treatments (fluoride therapy, anti-bacterial therapy, low intensity laser irradiation). Near-infrared (NIR) hyper-spectral imaging is a new promising technique for early detection of demineralization based on distinct spectral features of healthy and pathological dental tissues. In this study, we apply NIR hyper-spectral imaging to classify and visualize healthy and pathological dental tissues including enamel, dentin, calculus, dentin caries, enamel caries and demineralized areas. For this purpose, a standardized teeth database was constructed consisting of 12 extracted human teeth with different degrees of natural dental lesions imaged by NIR hyper-spectral system, X-ray and digital color camera. The color and X-ray images of teeth were presented to a clinical expert for localization and classification of the dental tissues, thereby obtaining the gold standard. Principal component analysis was used for multivariate local modeling of healthy and pathological dental tissues. Finally, the dental tissues were classified by employing multiple discriminant analysis. High agreement was observed between the resulting classification and the gold standard with the classification sensitivity and specificity exceeding 85 % and 97 %, respectively. This study demonstrates that NIR hyper-spectral imaging has considerable diagnostic potential for imaging hard dental tissues.

  13. Study on Dental Treatment with YAG Laser (1st Report): Temperature of Dental Tissue Irradiated with Laser Beam

    OpenAIRE

    上田, 隆司; 山田, 啓司; 古本, 達明

    2000-01-01

    The flash temperature of a dental hard tissue irradiated with pulsed Nd:YAG laser is measured using a two-color pyrometer with an optical fiber. This pyrometer consists of a chalcogenide optical fiber and a laminated infrared detector. The influence of the laser power on the temperature of the dental tissue is investigated, and the relationship between the laser power and the removal volume of the dental tissue is obtained. In order to examine the thermal damage on the dental tissue, hardness...

  14. Imunohistological aspects of the tissue around dental implants

    Science.gov (United States)

    Nimigean, Victor; Nimigean, Vanda R.; Sǎlǎvǎstru, Dan I.; Moraru, Simona; BuÅ£incu, Lavinia; Ivaşcu, Roxana V.; Poll, Alexandru

    2016-03-01

    Objectives: study of soft and hard tissues around implants. Material and methods: For the immunohistochemical and histological study of the implant/soft tissue interface, we examined pieces of peri-implant mucosa harvested from 35 patients. The implant/bone interface was assessed using histologic and histomorphometric examination of hard tissues around unloaded, early loaded or delayed loaded dental implants with pre-established design, with a sandblasted and acid-etched surface, placed both in extraction sockets, or after bone healing following tooth removal. This study was performed on 9 common race dogs. Results: The histological study of the implant/soft tissue interface showed regenerative modifications and moderate chronic subepithelial inflammatory reactions. Immunohistochemical evaluation of the soft tissue biopsies revealed the presence of specific immunocompetent cells and proteins of the matrix metalloproteinase (MMP) expression. Bone-implants contacts were more obvious in the apical half of the implants and at the edges of the threads, than between them. A mature, lamelliform bone containing lacunae with osteocytes and lack of connective tissue were noticed around implants that were late placed and loaded. The new-formed bone was also abundant in the crestal zone, not only in the apical part of the implants. Conclusions: A thorough understanding of the microstructure of dental implant/soft and hard tissue interface will improve the longevity of osseointegrated implants.

  15. Suitability of Different Natural and Synthetic Biomaterials for Dental Pulp Tissue Engineering.

    Science.gov (United States)

    Galler, Kerstin M; Brandl, Ferdinand P; Kirchhof, Susanne; Widbiller, Matthias; Eidt, Andreas; Buchalla, Wolfgang; Göpferich, Achim; Schmalz, Gottfried

    2018-02-01

    Dental pulp tissue engineering is possible after insertion of pulpal stem cells combined with a scaffold into empty root canals. Commonly used biomaterials are collagen or poly(lactic) acid, which are either difficult to modify or to insert into such a narrow space. New hydrogel scaffolds with bioactive, specifically tailored functions could optimize the conditions for this approach. Different synthetic and natural hydrogels were tested for their suitability to engineer dental pulp. Two functionalized modifications of polyethylene glycol were developed in this study and compared to a self-assembling peptide, as well as to collagen and fibrin. Cell viability of dental pulp stem cells in test materials was assessed over two weeks. Cells in selected test materials laden with dentin-derived growth factors were inserted into human tooth roots and implanted subcutaneously into immunocompromised mice. In vitro cell culture exhibited distinct differences between scaffold types, where viability was significantly higher in natural compared to synthetic materials. In vivo experiments showed considerable differences regarding scaffold degradation, soft tissue formation, vascularization, and odontoblast-like cell differentiation. Fibrin appeared most suitable to enable generation of a pulp-like tissue and differentiation of cells into odontoblasts at the cell-dentin interface. In conclusion, natural materials, especially fibrin, proved to be superior compared to synthetic scaffolds regarding cell viability and dental pulp-like tissue formation.

  16. RAMAN-SPECTRA OF HUMAN DENTAL CALCULUS

    NARCIS (Netherlands)

    TSUDA, H; ARENDS, J

    1993-01-01

    Raman spectra of human dental calculus have been observed for the first time by use of micro-Raman spectroscopy. The spectral features of calculus were influenced easily by heating caused by laser irradiation. Therefore, the measurements were carried out at relatively low power (5 mW, 1-mu m spot

  17. Microangiographic study of the canine dental tissues: a preliminary report

    International Nuclear Information System (INIS)

    Miyabayashi, T.; Morgan, J.P.

    1987-01-01

    A microangiographic study of the dental tissues was performed on one adult mongrel dog to examine the usefulness of the technique. This preliminary study used 30% wt/vol Micropaque suspension which was perfused into the common carotid arteries. After the complete perfusion, the specimen was fixed into a mixture of 10% buffered neutral formalin solution and 95% ethyl alcohol. The mandibular bone with teeth in situ was decalcified. The specimen was embedded in methyl methacrylate. One mm slab sections were made, and then the microangiographs were made. Adequate filling of arterioles was evident on the microangiographs. This technique is shown to be useful in characterizing the nature of the blood supply to the bone and teeth that might be involved in the pathogenesis of radiation-induced injury in the canine dental and periodontal tissues

  18. Improvement of In Vitro Osteogenic Potential through Differentiation of Induced Pluripotent Stem Cells from Human Exfoliated Dental Tissue towards Mesenchymal-Like Stem Cells

    Directory of Open Access Journals (Sweden)

    Felipe Augusto Andre Ishiy

    2015-01-01

    Full Text Available Constraints for the application of MSCs for bone reconstruction include restricted self-renewal and limited cell amounts. iPSC technology presents advantages over MSCs, providing homogeneous cellular populations with prolonged self-renewal and higher plasticity. However, it is unknown if the osteogenic potential of iPSCs differs from that of MSCs and if it depends on the iPSCs originating cellular source. Here, we compared the in vitro osteogenesis between stem cells from human deciduous teeth (SHED and MSC-like cells from iPSCs from SHED (iPS-SHED and from human dermal fibroblasts (iPS-FIB. MSC-like cells from iPS-SHED and iPS-FIB displayed fibroblast-like morphology, downregulation of pluripotency markers and upregulation of mesenchymal markers. Comparative in vitro osteogenesis analysis showed higher osteogenic potential in MSC-like cells from iPS-SHED followed by MSC-like cells from iPS-FIB and SHED. CD105 expression, reported to be inversely correlated with osteogenic potential in MSCs, did not display this pattern, considering that SHED presented lower CD105 expression. Higher osteogenic potential of MSC-like cells from iPS-SHED may be due to cellular homogeneity and/or to donor tissue epigenetic memory. Our findings strengthen the rationale for the use of iPSCs in bone bioengineering. Unveiling the molecular basis behind these differences is important for a thorough use of iPSCs in clinical scenarios.

  19. The fluorescence in the diagnosis of dental tissue

    International Nuclear Information System (INIS)

    Puron, E.; Homs, R.; Paya, R. M.

    2012-01-01

    An experimental method for obtaining fluorescence of the dental tissue is described. A comparative analysis for the behaviour of the tissue fluorescence, both, healthy or intact enamel and carious samples is presented; the comparison of the obtained results with the ones described in the literature is done. Optical methods for the detection of carious lesions have the advantage of being minimally invasive. For this reason, induced fluorescence with a blue light to detect the presence of the Streptococcus in the oral cavity is proposed as an identifier method for find initial caries in dentistry in our country. (Author)

  20. Human trafficking and the dental professional.

    Science.gov (United States)

    O'Callaghan, Michael G

    2012-05-01

    "Human trafficking" is a term for a modern form of slavery. It is a criminal human rights violation and a significant health issue. Dental professionals can assist in recognizing victims of trafficking. The author conducted a PubMed search of the English-language literature through May 2011, which yielded no articles meeting the search criteria "dentistry" and "human trafficking prostitution." Given these results, the author reviewed articles published in medical journals, reports from both governmental and nongovernmental agencies and lay literature. The author examines the present state of human trafficking and provides information--including specific questions to ask--to help dentists identify victims. In addition, the author suggests means of notifying authorities and assisting trafficking victims. He also examines the health care needs of these patients. Human trafficking is a global problem, with thousands of victims in the United States, including many women and children. Dentists have a responsibility to act for the benefit of others, which includes detecting signs of abuse and neglect. Dental professionals are on the front lines with respect to encountering and identifying potential victims who seek dental treatment. Dentists can combat human trafficking by becoming informed and by maintaining vigilance in their practices.

  1. Microarray expression profiling of human dental pulp from single subject.

    Science.gov (United States)

    Tete, Stefano; Mastrangelo, Filiberto; Scioletti, Anna Paola; Tranasi, Michelangelo; Raicu, Florina; Paolantonio, Michele; Stuppia, Liborio; Vinci, Raffaele; Gherlone, Enrico; Ciampoli, Cristian; Sberna, Maria Teresa; Conti, Pio

    2008-01-01

    Microarray is a recently developed simultaneous analysis of expression patterns of thousand of genes. The aim of this research was to evaluate the expression profile of human healthy dental pulp in order to find the presence of genes activated and encoding for proteins involved in the physiological process of human dental pulp. We report data obtained by analyzing expression profiles of human tooth pulp from single subjects, using an approach based on the amplification of the total RNA. Experiments were performed on a high-density array able to analyse about 21,000 oligonucleotide sequences of about 70 bases in duplicate, using an approach based on the amplification of the total RNA from the pulp of a single tooth. Obtained data were analyzed using the S.A.M. system (Significance Analysis of Microarray) and genes were merged according to their molecular functions and biological process by the Onto-Express software. The microarray analysis revealed 362 genes with specific pulp expression. Genes showing significant high expression were classified in genes involved in tooth development, protoncogenes, genes of collagen, DNAse, Metallopeptidases and Growth factors. We report a microarray analysis, carried out by extraction of total RNA from specimens of healthy human dental pulp tissue. This approach represents a powerful tool in the study of human normal and pathological pulp, allowing minimization of the genetic variability due to the pooling of samples from different individuals.

  2. Hard tissue formation in a porous HA/TCP ceramic scaffold loaded with stromal cells derived from dental pulp and bone marrow.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Osch, G.J.V.M. van; Dolder, J. van den; Jansen, J.A.

    2008-01-01

    The aim of this study was to compare the ability of hard tissue regeneration of four types of stem cells or precursors under both in vitro and in vivo situations. Primary cultures of rat bone marrow, rat dental pulp, human bone marrow, and human dental pulp cells were seeded onto a porous ceramic

  3. Improved classification and visualization of healthy and pathological hard dental tissues by modeling specular reflections in NIR hyperspectral images

    Science.gov (United States)

    Usenik, Peter; Bürmen, Miran; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2012-03-01

    Despite major improvements in dental healthcare and technology, dental caries remains one of the most prevalent chronic diseases of modern society. The initial stages of dental caries are characterized by demineralization of enamel crystals, commonly known as white spots, which are difficult to diagnose. Near-infrared (NIR) hyperspectral imaging is a new promising technique for early detection of demineralization which can classify healthy and pathological dental tissues. However, due to non-ideal illumination of the tooth surface the hyperspectral images can exhibit specular reflections, in particular around the edges and the ridges of the teeth. These reflections significantly affect the performance of automated classification and visualization methods. Cross polarized imaging setup can effectively remove the specular reflections, however is due to the complexity and other imaging setup limitations not always possible. In this paper, we propose an alternative approach based on modeling the specular reflections of hard dental tissues, which significantly improves the classification accuracy in the presence of specular reflections. The method was evaluated on five extracted human teeth with corresponding gold standard for 6 different healthy and pathological hard dental tissues including enamel, dentin, calculus, dentin caries, enamel caries and demineralized regions. Principal component analysis (PCA) was used for multivariate local modeling of healthy and pathological dental tissues. The classification was performed by employing multiple discriminant analysis. Based on the obtained results we believe the proposed method can be considered as an effective alternative to the complex cross polarized imaging setups.

  4. Successful isolation, in vitro expansion and characterization of stem cells from Human Dental Pulp

    OpenAIRE

    Preethy SP; Srinivasan T; Tholcopiyan L; Thamaraikannan P; Srinivasan V; Murugan P; Manjunath S; Kannan TA; Shalini R; Sunil PM; Manikandhan R; Muthu MS; Abraham S

    2010-01-01

    BACKGROUND: Recent studies have shown that mesenchymal stem cells isolated from post natal human dental pulp, (Dental pulp stem cells-DPSCs) which is from permanent teeth and SHED (stem cells from human exfoliated deciduous teeth),the Periodontal ligament stem cells (PDLSC) and Stem cells from root Apical papilla(SCAP)have the potential to differentiate into cells of a variety of tissues including heart, muscle, cartilage, bone, nerve, salivary glands, teeth etc(1,2,3,4).This multipotential a...

  5. Random lasing in human tissues

    International Nuclear Information System (INIS)

    Polson, Randal C.; Vardeny, Z. Valy

    2004-01-01

    A random collection of scatterers in a gain medium can produce coherent laser emission lines dubbed 'random lasing'. We show that biological tissues, including human tissues, can support coherent random lasing when infiltrated with a concentrated laser dye solution. To extract a typical random resonator size within the tissue we average the power Fourier transform of random laser spectra collected from many excitation locations in the tissue; we verified this procedure by a computer simulation. Surprisingly, we found that malignant tissues show many more laser lines compared to healthy tissues taken from the same organ. Consequently, the obtained typical random resonator was found to be different for healthy and cancerous tissues, and this may lead to a technique for separating malignant from healthy tissues for diagnostic imaging

  6. Advances of mesenchymal stem cells derived from bone marrow and dental tissue in craniofacial tissue engineering.

    Science.gov (United States)

    Yang, Maobin; Zhang, Hongming; Gangolli, Riddhi

    2014-05-01

    Bone and dental tissues in craniofacial region work as an important aesthetic and functional unit. Reconstruction of craniofacial tissue defects is highly expected to ensure patients to maintain good quality of life. Tissue engineering and regenerative medicine have been developed in the last two decades, and been advanced with the stem cell technology. Bone marrow derived mesenchymal stem cells are one of the most extensively studied post-natal stem cell population, and are widely utilized in cell-based therapy. Dental tissue derived mesenchymal stem cells are a relatively new stem cell population that isolated from various dental tissues. These cells can undergo multilineage differentiation including osteogenic and odontogenic differentiation, thus provide an alternative source of mesenchymal stem cells for tissue engineering. In this review, we discuss the important issues in mesenchymal stem cell biology including the origin and functions of mesenchymal stem cells, compare the properties of these two types of mesenchymal cells, update recent basic research and clinic applications in this field, and address important future challenges.

  7. Osteogenic differentiation of human dental papilla mesenchymal cells

    International Nuclear Information System (INIS)

    Ikeda, Etsuko; Hirose, Motohiro; Kotobuki, Noriko; Shimaoka, Hideki; Tadokoro, Mika; Maeda, Masahiko; Hayashi, Yoshiko; Kirita, Tadaaki; Ohgushi, Hajime

    2006-01-01

    We isolated dental papilla from impacted human molar and proliferated adherent fibroblastic cells after collagenase treatment of the papilla. The cells were negative for hematopoietic markers but positive for CD29, CD44, CD90, CD105, and CD166. When the cells were further cultured in the presence of β-glycerophosphate, ascorbic acid, and dexamethasone for 14 days, mineralized areas together with osteogenic differentiation evidenced by high alkaline phosphatase activity and osteocalcin contents were observed. The differentiation was confirmed at both protein and gene expression levels. The cells can also be cryopreserved and, after thawing, could show in vivo bone-forming capability. These results indicate that mesenchymal type cells localize in dental papilla and that the cells can be culture expanded/utilized for bone tissue engineering

  8. Microarray evaluation of age-related changes in human dental pulp.

    Science.gov (United States)

    Tranasi, Michelangelo; Sberna, Maria Teresa; Zizzari, Vincenzo; D'Apolito, Giuseppe; Mastrangelo, Filiberto; Salini, Luisa; Stuppia, Liborio; Tetè, Stefano

    2009-09-01

    The dental pulp undergoes age-related changes that could be ascribed to physiological, defensive, or pathological irritant-induced changes. These changes are regulated by pulp cell activity and by a variety of extracellular matrix (ECM) macromolecules, playing important roles in growth regulation, tissue differentiation and organization, formation of calcified tissue, and defense mechanisms and reactions to inflammatory stimuli. The aim of this research was to better understand the genetic changes that underlie the histological modification of the dental pulp in aging. The gene expression profile of the human dental pulp in young and older subjects was compared by RNA microarray analysis that allowed to simultaneously analyze the expression levels of thousands of genes. Data were statistically analyzed by Significance Analysis of Microarrays (SAM) Ingenuity Pathway Analysis (IPA) software. Semiquantitative and real-time reverse-transcriptase polymerase chain reaction analyses were performed to confirm the results. Microarray analysis revealed several differentially expressed genes that were categorized in growth factors, transcription regulators, apoptosis regulators, and genes of the ECM. The comparison analysis showed a high expression level of the biological functions of cell and tissue differentiation, development, and proliferation and of the immune, lymphatic, and hematologic system in young dental pulp, whereas the pathway of apoptosis was highly expressed in older dental pulp. Expression profile analyses of human dental pulp represent a sensible and useful tool for the study of mechanisms involved in differentiation, growth and aging of human dental pulp in physiological and pathological conditions.

  9. Investigation of ultrashort-pulsed laser on dental hard tissue

    Science.gov (United States)

    Uchizono, Takeyuki; Awazu, Kunio; Igarashi, Akihiro; Kato, Junji; Hirai, Yoshito

    2007-02-01

    Ultrashort-pulsed laser (USPL) can ablate various materials with precious less thermal effect. In laser dentistry, to solve the problem that were the generation of crack and carbonized layer by irradiating with conventional laser such as Er:YAG and CO II laser, USPL has been studied to ablate dental hard tissues by several researchers. We investigated the effectiveness of ablation on dental hard tissues by USPL. In this study, Ti:sapphire laser as USPL was used. The laser parameter had the pulse duration of 130 fsec, 800nm wavelength, 1KHz of repetition rate and the average power density of 90~360W/cm2. Bovine root dentin plates and crown enamel plates were irradiated with USPL at 1mm/sec using moving stage. The irradiated samples were analyzed by SEM, EDX, FTIR and roughness meter. In all irradiated samples, the cavity margin and wall were sharp and steep, extremely. In irradiated dentin samples, the surface showed the opened dentin tubules and no smear layer. The Ca/P ratio by EDX measurement and the optical spectrum by FTIR measurement had no change on comparison irradiated samples and non-irradiated samples. These results confirmed that USPL could ablate dental hard tissue, precisely and non-thermally. In addition, the ablation depths of samples were 10μm, 20μm, and 60μm at 90 W/cm2, 180 W/cm2, and 360 W/cm2, approximately. Therefore, ablation depth by USPL depends on the average power density. USPL has the possibility that can control the precision and non-thermal ablation with depth direction by adjusting the irradiated average power density.

  10. General evaluation of hard dental tissue and risk factors of dental caries in young people

    Directory of Open Access Journals (Sweden)

    Антоніна Михайлівна Політун

    2016-04-01

    Full Text Available The prognostication of caries in youth is important for determination and prescription of individual prophylactic arrangements and its further influence on mineralization of the hard dental tissues.Aim of the work: the study of the prevalence and intensity of caries among the young people and determination of possible connection with the risk factor of caries development for further choice of the reasonable prophylactic arrangement.Materials and methods of research: epidemiological, clinical, statistic ones.Results of research: The article describes results of the comprehensive dental examination of 135 persons18-25 years old. There was determined the high prevalence of caries (96,3±0,74 % with considerable intensity (8,87±0,39. The main etiological factors among youth are: poor nutrition with prevalence of carbohydrate (74,81±0,56 %, lack of oral hygiene (59,27±0,73 %, quantitative and qualitative composition of oral fluid, presence of somatic diseases (40±0,30 %, bad habits (31,85±0,24 %, neglect of the sport (48,88±0,36 %, chronic emotional stress (38,51±0,29 %, due to the increased workload and related stress factors.Conclusions: the high prevalence (96,3±0,74 % and intensity of carious process (8,87±0,39 is caused by the unsatisfactory state of oral cavity, (1,91±0,06, under the influence of general factors (somatic diseases, stress, poor nutrition the reactivity of protective mechanisms is lowered and the risk of dental morbidity of youth increases. So, it proves the necessity of elaboration and introduction of the active arrangements of primary prophylaxis directed on the raise of caries resistance of the hard dental tissues in young people

  11. A tissue-dependent hypothesis of dental caries.

    Science.gov (United States)

    Simón-Soro, A; Belda-Ferre, P; Cabrera-Rubio, R; Alcaraz, L D; Mira, A

    2013-01-01

    Current understanding of dental caries considers this disease a demineralization of the tooth tissues due to the acid produced by sugar-fermenting microorganisms. Thus, caries is considered a diet- and pH-dependent process. We present here the first metagenomic analysis of the bacterial communities present at different stages of caries development, with the aim of determining whether the bacterial composition and biochemical profile are specific to the tissue affected. The data show that microbial composition at the initial, enamel-affecting stage of caries is significantly different from that found at subsequent stages, as well as from dental plaque of sound tooth surfaces. Although the relative proportion of Streptococcus mutans increased from 0.12% in dental plaque to 0.72% in enamel caries, Streptococcus mitis and Streptococcus sanguinis were the dominant streptococci in these lesions. The functional profile of caries-associated bacterial communities indicates that genes involved in acid stress tolerance and dietary sugar fermentation are overrepresented only at the initial stage (enamel caries), whereas other genes coding for osmotic stress tolerance as well as collagenases and other proteases enabling dentin degradation are significantly overrepresented in dentin cavities. The results support a scenario in which pH and diet are determinants of the disease during the degradation of enamel, but in dentin caries lesions not only acidogenic but also proteolytic bacteria are involved. We propose that caries disease is a process of varying etiology, in which acid-producing bacteria are the vehicle to penetrate enamel and allow dentin degrading microorganisms to expand the cavity. © 2013 S. Karger AG, Basel.

  12. Inhibition of odontogenic differentiation of human dental pulp cells by dental resin monomers.

    Science.gov (United States)

    Kwon, Ji Hyun; Park, Hee Chul; Zhu, Tingting; Yang, Hyeong-Cheol

    2015-01-01

    Dental resin monomers that are leached from the resin matrix due to incomplete polymerization can affect the viability and various functions of oral tissues and cells. In this study, the effects of triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) on odontogenic differentiation of human dental pulp cells (HDPCs) were examined. To mimic clinical situations, dental pulp cells were treated with resin monomers for 24 h prior to the analysis of alkaline phosphatase (ALP) activity and mRNA expression of genes related to pulp cell differentiation. To elucidate the underlying signaling pathways, regulation of mitogen-activated protein (MAP) kinases by resin monomers was also investigated. The ALP activity of HDPCs was reduced by TEGDMA and HEMA at noncytotoxic concentrations. The mRNA expression of dentin sialophosphoprotein (DSPP), osteocalcin (OCN), and osteopontin (OPN) was also downregulated by resin monomers. However, DSPP expression was not affected by hydrogen peroxide (H2O2). Among the MAP kinases examined, ERK activation (ERK phosphorylation) was not affected by either resin monomers or H2O2, whereas JNK was phosphorylated by TEGDMA and HEMA. Phospho-p38 was upregulated by HEMA, while TEGDMA and H2O2 suppressed p38 phosphorylation. Exposure to TEGDMA and HEMA for a limited period suppresses differentiation of HDPCs via different signaling pathways.

  13. Dimensional soft tissue changes following soft tissue grafting in conjunction with implant placement or around present dental implants: a systematic review.

    Science.gov (United States)

    Poskevicius, Lukas; Sidlauskas, Antanas; Galindo-Moreno, Pablo; Juodzbalys, Gintaras

    2017-01-01

    To systematically review changes in mucosal soft tissue thickness and keratinised mucosa width after soft tissue grafting around dental implants. An electronic literature search was conducted of the MEDLINE database published between 2009 and 2014. Sequential screenings at the title, abstract, and full-text levels were performed. Clinical human studies in the English language that had reported changes in soft tissue thickness or keratinised mucosa width after soft tissue grafting at implant placement or around a present implant at 6-month follow-up or longer were included. The search resulted in fourteen articles meeting the inclusion criteria: Six of them reported connective tissue grafting around present dental implants, compared to eight at the time of implant placement. Better long-term soft tissue thickness outcomes were reported for soft tissue augmentation around dental implants (0.8-1.4 mm), compared with augmentation at implant placement (-0.25-1.43 mm). Both techniques were effective in increasing keratinised tissue width: at implant placement (2.5 mm) or around present dental implants (2.33-2.57 mm). The present systematic review discovered that connective tissue grafts enhanced keratinised mucosa width and soft tissue thickness for an observation period of up to 48 months. However, some shrinkage may occur, resulting in decreases in soft tissue, mostly for the first three months. Further investigations using accurate evaluation methods need to be done to evaluate the appropriate time for grafting. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. REE compositions in fossil vertebrate dental tissues indicate biomineral preservation

    Science.gov (United States)

    Žigaite, Ž.; Kear, B.; Pérez-Huerta, A.; Jeffries, T.; Blom, H.

    2012-04-01

    Rare earth element (REE) abundances have been measured in a number of Palaeozoic and Mesozoic dental tissues using Laser Ablation Inductively Coupled Plasma Mass-spectrometry (LA-ICP-MS). Fossil vertebrates analysed comprise scales and tesserae of Silurian and Devonian acanthodians, chondrichthyans, galeaspids, mongolepids, thelodonts, as well as teeth of Cretaceous lungfish and marine reptiles. The evaluation of fossil preservation level has been made by semi-quantitative spot geochemistry analyses on fine polished teeth and scale thin sections, using Energy Dispersive X-ray Spectroscopy (EDS). Fossil teeth and scales with significant structure and colour alteration have shown elevated heavy element concentrations, and the silicification of bioapatite has been common in their tissues. Stable oxygen isotope measurements (δ18O) of bulk biomineral have been conducted in parallel, and showed comparatively lower heavy oxygen values in the same fossil tissues with stronger visible alteration. Significant difference in REE concentrations has been observed between the dentine and enamel of Cretaceous plesiosaurs, suggesting the enamel to be more geochemically resistant to diagenetic overprint.

  15. Direct spectrometry: a new alternative for measuring the fluorescence of composite resins and dental tissues.

    Science.gov (United States)

    da Silva, Tm; de Oliveira, Hpm; Severino, D; Balducci, I; Huhtala, Mfrl; Gonçalves, Sep

    2014-01-01

    The aim of this study was to evaluate the fluorescence intensity of different composite resins and compare those values with the fluorescence intensity of dental tissues. Different composite resins were used to make 10 discs (2 mm in depth and 4 mm in diameter) of each brand, divided into groups: 1) Z (Filtek Z350, 3M ESPE), 2) ES (Esthet-X, Dentsply), 3) A (Amelogen Plus, Ultradent), 4) DVS (Durafill-VS, Heraeus Kulzer) with 2 mm composite resin for enamel (A2), 5) OES ([Esthet-X] opaque-OA [1 mm] + enamel-A2 [1 mm]); 6) ODVSI ([Charisma-Opal/Durafill-VSI], opaque-OM (1 mm) + translucent [1mm]), and 7) DVSI ([Durafill- VSI] translucent [2 mm]). Dental tissue specimens were obtained from human anterior teeth cut in a mesiodistal direction to obtain enamel, dentin, and enamel/dentin samples (2 mm). The fluorescence intensity of specimens was directly measured using an optic fiber associated with a spectrometer (Ocean Optics USB 4000) and recorded in graphic form (Origin 8.0 program). Data were submitted to statistical analysis using Dunnet, Tukey, and Kruskall-Wallis tests. Light absorption of the composite resins was obtained in a spectral range from 250 to 450 nm, and that of dental tissues was between 250 and 300 nm. All composite resins were excited at 398 nm and exhibited maximum emissions of around 485 nm. Fluorescence intensity values for all of the resins showed statistically significant differences (measured in arbitrary units [AUs]), with the exception of groups Z and DVS. Group DVSI had the highest fluorescence intensity values (13539 AU), followed by ODVS (10440 AU), DVS (10146 AU), ES (3946 AU), OES (3841 AU), A (3540 AU), and Z (1146 AU). The fluorescence intensity values for the composite resins differed statistically from those of dental tissues (E=1380 AU; D=6262 AU; E/D=3251 AU). The opacity interfered with fluorescence intensity, and group Z demonstrated fluorescence intensity values closest to that of tooth enamel. It is concluded that the

  16. Multilineage potential and proteomic profiling of human dental stem cells derived from a single donor

    International Nuclear Information System (INIS)

    Patil, Rajreddy; Kumar, B. Mohana; Lee, Won-Jae; Jeon, Ryoung-Hoon; Jang, Si-Jung; Lee, Yeon-Mi; Park, Bong-Wook; Byun, June-Ho; Ahn, Chun-Seob; Kim, Jae-Won; Rho, Gyu-Jin

    2014-01-01

    Dental tissues provide an alternative autologous source of mesenchymal stem cells (MSCs) for regenerative medicine. In this study, we isolated human dental MSCs of follicle, pulp and papilla tissue from a single donor tooth after impacted third molar extraction by excluding the individual differences. We then compared the morphology, proliferation rate, expression of MSC-specific and pluripotency markers, and in vitro differentiation ability into osteoblasts, adipocytes, chondrocytes and functional hepatocyte-like cells (HLCs). Finally, we analyzed the protein expression profiles of undifferentiated dental MSCs using 2DE coupled with MALDI-TOF-MS. Three types of dental MSCs largely shared similar morphology, proliferation potential, expression of surface markers and pluripotent transcription factors, and differentiation ability into osteoblasts, adipocytes, and chondrocytes. Upon hepatogenic induction, all MSCs were transdifferentiated into functional HLCs, and acquired hepatocyte functions by showing their ability for glycogen storage and urea production. Based on the proteome profiling results, we identified nineteen proteins either found commonly or differentially expressed among the three types of dental MSCs. In conclusion, three kinds of dental MSCs from a single donor tooth possessed largely similar cellular properties and multilineage potential. Further, these dental MSCs had similar proteomic profiles, suggesting their interchangeable applications for basic research and call therapy. - Highlights: • Isolated and characterized three types of human dental MSCs from a single donor. • MSCs of dental follicle, pulp and papilla had largely similar biological properties. • All MSCs were capable of transdifferentiating into functional hepatocyte-like cells. • 2DE proteomics with MALDI-TOF/MS identified 19 proteins in three types of MSCs. • Similar proteomic profiles suggest interchangeable applications of dental MSCs

  17. Multilineage potential and proteomic profiling of human dental stem cells derived from a single donor

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Rajreddy; Kumar, B. Mohana; Lee, Won-Jae; Jeon, Ryoung-Hoon; Jang, Si-Jung; Lee, Yeon-Mi [Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Park, Bong-Wook; Byun, June-Ho [Department of Oral and Maxillofacial Surgery, School of Medicine and Institute of Health Science, Gyeongsang National University, Jinju 660-702 (Korea, Republic of); Ahn, Chun-Seob; Kim, Jae-Won [Department of Microbiology, Division of Life Sciences, Research Institute of Life Science, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Rho, Gyu-Jin, E-mail: jinrho@gnu.ac.kr [Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701 (Korea, Republic of); Research Institute of Life Sciences, Gyeongsang National University, Jinju 660-701 (Korea, Republic of)

    2014-01-01

    Dental tissues provide an alternative autologous source of mesenchymal stem cells (MSCs) for regenerative medicine. In this study, we isolated human dental MSCs of follicle, pulp and papilla tissue from a single donor tooth after impacted third molar extraction by excluding the individual differences. We then compared the morphology, proliferation rate, expression of MSC-specific and pluripotency markers, and in vitro differentiation ability into osteoblasts, adipocytes, chondrocytes and functional hepatocyte-like cells (HLCs). Finally, we analyzed the protein expression profiles of undifferentiated dental MSCs using 2DE coupled with MALDI-TOF-MS. Three types of dental MSCs largely shared similar morphology, proliferation potential, expression of surface markers and pluripotent transcription factors, and differentiation ability into osteoblasts, adipocytes, and chondrocytes. Upon hepatogenic induction, all MSCs were transdifferentiated into functional HLCs, and acquired hepatocyte functions by showing their ability for glycogen storage and urea production. Based on the proteome profiling results, we identified nineteen proteins either found commonly or differentially expressed among the three types of dental MSCs. In conclusion, three kinds of dental MSCs from a single donor tooth possessed largely similar cellular properties and multilineage potential. Further, these dental MSCs had similar proteomic profiles, suggesting their interchangeable applications for basic research and call therapy. - Highlights: • Isolated and characterized three types of human dental MSCs from a single donor. • MSCs of dental follicle, pulp and papilla had largely similar biological properties. • All MSCs were capable of transdifferentiating into functional hepatocyte-like cells. • 2DE proteomics with MALDI-TOF/MS identified 19 proteins in three types of MSCs. • Similar proteomic profiles suggest interchangeable applications of dental MSCs.

  18. Decellularized Human Dental Pulp as a Scaffold for Regenerative Endodontics.

    Science.gov (United States)

    Song, J S; Takimoto, K; Jeon, M; Vadakekalam, J; Ruparel, N B; Diogenes, A

    2017-06-01

    Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis.

  19. Nigerian Dental Technology Students and Human ...

    African Journals Online (AJOL)

    study of dental technology students of Federal School of Dental Therapy and Technology. Enugu, Nigeria ... HIV-infected individuals is also known to be achieved through the provision of ... to care for HIV-infected patients among this group of dental professionals ..... Table 7: Willingness to care versus training needs on care.

  20. Fluorescence properties of human teeth and dental calculus for clinical applications

    Science.gov (United States)

    Lee, Yong-Keun

    2015-04-01

    Fluorescent emission of human teeth and dental calculus is important for the esthetic rehabilitation of teeth, diagnosis of dental caries, and detection of dental calculus. The purposes of this review were to summarize the fluorescence and phosphorescence of human teeth by ambient ultraviolet (UV) light, to investigate the clinically relevant fluorescence measurement methods in dentistry, and to review the fluorescence of teeth and dental calculus by specific wavelength light. Dentine was three times more phosphorescent than enamel. When exposed to light sources containing UV components, the fluorescence of human teeth gives them the quality of vitality, and fluorescent emission with a peak of 440 nm is observed. Esthetic restorative materials should have fluorescence properties similar to those of natural teeth. Based on the fluorescence of teeth and restorative materials as determined with a spectrophotometer, a fluorescence parameter was defined. As to the fluorescence spectra by a specific wavelength, varied wavelengths were investigated for clinical applications, and several methods for the diagnosis of dental caries and the detection of dental calculus were developed. Since fluorescent properties of dental hard tissues have been used and would be expanded in diverse fields of clinical practice, these properties should be investigated further, embracing newly developed optical techniques.

  1. Successful enrichment and recovery of whole mitochondrial genomes from ancient human dental calculus.

    Science.gov (United States)

    Ozga, Andrew T; Nieves-Colón, Maria A; Honap, Tanvi P; Sankaranarayanan, Krithivasan; Hofman, Courtney A; Milner, George R; Lewis, Cecil M; Stone, Anne C; Warinner, Christina

    2016-06-01

    Archaeological dental calculus is a rich source of host-associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis. Extracted DNA from six individuals at the 700-year-old Norris Farms #36 cemetery in Illinois was enriched for mtDNA using in-solution capture techniques, followed by Illumina high-throughput sequencing. Full mitogenomes (7-34×) were successfully reconstructed from dental calculus for all six individuals, including three individuals who had previously tested negative for DNA preservation in bone using conventional PCR techniques. Mitochondrial haplogroup assignments were consistent with previously published findings, and additional comparative analysis of paired dental calculus and dentine from two individuals yielded equivalent haplotype results. All dental calculus samples exhibited damage patterns consistent with ancient DNA, and mitochondrial sequences were estimated to be 92-100% endogenous. DNA polymerase choice was found to impact error rates in downstream sequence analysis, but these effects can be mitigated by greater sequencing depth. Dental calculus is a viable alternative source of human DNA that can be used to reconstruct full mitogenomes from archaeological remains. Am J Phys Anthropol 160:220-228, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Mesenchymal Stem Cells of Dental Origin for Inducing Tissue Regeneration in Periodontitis: A Mini-Review

    Directory of Open Access Journals (Sweden)

    Beatriz Hernández-Monjaraz

    2018-03-01

    Full Text Available Periodontitis is a chronic disease that begins with a period of inflammation of the supporting tissues of the teeth table and then progresses, destroying the tissues until loss of the teeth occurs. The restoration of the damaged dental support apparatus is an extremely complex process due to the regeneration of the cementum, the periodontal ligament, and the alveolar bone. Conventional treatment relies on synthetic materials that fill defects and replace lost dental tissue, but these approaches are not substitutes for a real regeneration of tissue. To address this, there are several approaches to tissue engineering for regenerative dentistry, among them, the use of stem cells. Mesenchymal stem cells (MSC can be obtained from various sources of adult tissues, such as bone marrow, adipose tissue, skin, and tissues of the orofacial area. MSC of dental origin, such as those found in the bone marrow, have immunosuppressive and immunotolerant properties, multipotency, high proliferation rates, and the capacity for tissue repair. However, they are poorly used as sources of tissue for therapeutic purposes. Their accessibility makes them an attractive source of mesenchymal stem cells, so this review describes the field of dental stem cell research and proposes a potential mechanism involved in periodontal tissue regeneration induced by dental MSC.

  3. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Directory of Open Access Journals (Sweden)

    Ji-Hee Kim

    Full Text Available Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR. Other teeth were used for immunohistochemical analysis (IHC. Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1 was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1, leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5, and gamma-aminobutyric acid A receptor beta 1 (GABRB1 were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  4. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Science.gov (United States)

    Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K; Kim, Seong-Oh

    2014-01-01

    Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  5. Beeswax as dental filling on a neolithic human tooth.

    Science.gov (United States)

    Bernardini, Federico; Tuniz, Claudio; Coppa, Alfredo; Mancini, Lucia; Dreossi, Diego; Eichert, Diane; Turco, Gianluca; Biasotto, Matteo; Terrasi, Filippo; De Cesare, Nicola; Hua, Quan; Levchenko, Vladimir

    2012-01-01

    Evidence of prehistoric dentistry has been limited to a few cases, the most ancient dating back to the Neolithic. Here we report a 6500-year-old human mandible from Slovenia whose left canine crown bears the traces of a filling with beeswax. The use of different analytical techniques, including synchrotron radiation computed micro-tomography (micro-CT), Accelerator Mass Spectrometry (AMS) radiocarbon dating, Infrared (IR) Spectroscopy and Scanning Electron Microscopy (SEM), has shown that the exposed area of dentine resulting from occlusal wear and the upper part of a vertical crack affecting enamel and dentin tissues were filled with beeswax shortly before or after the individual's death. If the filling was done when the person was still alive, the intervention was likely aimed to relieve tooth sensitivity derived from either exposed dentine and/or the pain resulting from chewing on a cracked tooth: this would provide the earliest known direct evidence of therapeutic-palliative dental filling.

  6. Beeswax as dental filling on a neolithic human tooth.

    Directory of Open Access Journals (Sweden)

    Federico Bernardini

    Full Text Available Evidence of prehistoric dentistry has been limited to a few cases, the most ancient dating back to the Neolithic. Here we report a 6500-year-old human mandible from Slovenia whose left canine crown bears the traces of a filling with beeswax. The use of different analytical techniques, including synchrotron radiation computed micro-tomography (micro-CT, Accelerator Mass Spectrometry (AMS radiocarbon dating, Infrared (IR Spectroscopy and Scanning Electron Microscopy (SEM, has shown that the exposed area of dentine resulting from occlusal wear and the upper part of a vertical crack affecting enamel and dentin tissues were filled with beeswax shortly before or after the individual's death. If the filling was done when the person was still alive, the intervention was likely aimed to relieve tooth sensitivity derived from either exposed dentine and/or the pain resulting from chewing on a cracked tooth: this would provide the earliest known direct evidence of therapeutic-palliative dental filling.

  7. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    Science.gov (United States)

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

  8. X-Ray pictures of the developmental anomalis of the hard dental tissue

    International Nuclear Information System (INIS)

    Cecetkova, A.; Ondrasovicova, J.

    2008-01-01

    Dental anomalies are rare lessions of the hard dental tissue. They are as symptoms varies of the syndromes. They are as follow: hyperdoncia, hypodoncia, oligodoncia, anodoncia, mesiodens, macrodoncia and microdoncia. All of the above anomalis are detected by X-ray diagnostics ( intraoral and extra-oral radiography ). (authors)

  9. Forensic considerations when dealing with incinerated human dental remains.

    Science.gov (United States)

    Reesu, Gowri Vijay; Augustine, Jeyaseelan; Urs, Aadithya B

    2015-01-01

    Establishing the human dental identification process relies upon sufficient post-mortem data being recovered to allow for a meaningful comparison with ante-mortem records of the deceased person. Teeth are the most indestructible components of the human body and are structurally unique in their composition. They possess the highest resistance to most environmental effects like fire, desiccation, decomposition and prolonged immersion. In most natural as well as man-made disasters, teeth may provide the only means of positive identification of an otherwise unrecognizable body. It is imperative that dental evidence should not be destroyed through erroneous handling until appropriate radiographs, photographs, or impressions can be fabricated. Proper methods of physical stabilization of incinerated human dental remains should be followed. The maintenance of integrity of extremely fragile structures is crucial to the successful confirmation of identity. In such situations, the forensic dentist must stabilise these teeth before the fragile remains are transported to the mortuary to ensure preservation of possibly vital identification evidence. Thus, while dealing with any incinerated dental remains, a systematic approach must be followed through each stage of evaluation of incinerated dental remains to prevent the loss of potential dental evidence. This paper presents a composite review of various studies on incinerated human dental remains and discusses their impact on the process of human identification and suggests a step by step approach. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  10. [Correlation between PMI and DNA degradation of costicartilage and dental pulp cells in human being].

    Science.gov (United States)

    Long, Ren; Wang, Wei-ping; Xiong, Ping

    2005-08-01

    To probe the correlation between the postmortem interval (PMI) and the DNA degradation of costicartilage and dental pulp cells in human being after death, and to seek a new method for estimating PMI. The image cytometry was used to measure the DNA degradation under different ambient temperatures (30-35 degrees C, 15-20 degrees C) in 0-15 days after death. The average DNA content of two kinds of tissue was degradated with the prolongation of PMI. But there was a plateau period of 0-4 days for dental pulp cells of human being in 15-20 degrees C. There was a high negative correlativity PPMI. PMI could be estimated accurately according to the DNA degradation of costicartilage and dental pulp cells in human being after death.

  11. Implications of human tissue studies

    International Nuclear Information System (INIS)

    Kathren, R.L.

    1986-10-01

    Through radiochemical analysis of voluntary tissue donations, the United States Transuranium and Uranium Registries are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole body contributions to the Transuranium Registry revealed an inverse proportionality between actinide concentration and bone ash fraction. The analysis of a whole body with a documented 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies of the Registries are designed to evaluate in vivo estimates of actinide deposition with those derived from postmortem tissue analysis, compare results of animal experiments with human data, and reviw histopathologic slides for tissue toxicity that might be attributable to exposure to uranium and the transuranic elements. The implications of these recent findings and other work of the Registries are discussed from the standpoint of their potential impact on biokinetic modeling, internal dose assessment, safety standards, and operational health physics practices

  12. Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair

    Directory of Open Access Journals (Sweden)

    Zhi Chen

    2010-09-01

    Full Text Available Introduction: Dentin sialoprotein (DSP is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models.The hypothesis: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete dentin extracellular matrix forming new tertiary dentin as well as to regenerate a functional dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth.Evaluation of the hypothesis: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate dentin-pulp complex and restore its functions by DSP induction in vivo.

  13. Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair.

    Science.gov (United States)

    Yuan, Guo-Hua; Yang, Guo-Bin; Wu, Li-An; Chen, Zhi; Chen, Shuo

    2010-01-01

    INTRODUCTION: Dentin sialoprotein (DSP) is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models. THE HYPOTHESIS: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete dentin extracellular matrix forming new tertiary dentin as well as to regenerate a functional dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth. EVALUATION OF THE HYPOTHESIS: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate dentin-pulp complex and restore its functions by DSP induction in vivo.

  14. Human tissue in systems medicine.

    Science.gov (United States)

    Caie, Peter D; Schuur, Klaas; Oniscu, Anca; Mullen, Peter; Reynolds, Paul A; Harrison, David J

    2013-12-01

    Histopathology, the examination of an architecturally artefactual, two-dimensional and static image remains a potent tool allowing diagnosis and empirical expectation of prognosis. Considerable optimism exists that the advent of molecular genetic testing and other biomarker strategies will improve or even replace this ancient technology. A number of biomarkers already add considerable value for prediction of whether a treatment will work. In this short review we argue that a systems medicine approach to pathology will not seek to replace traditional pathology, but rather augment it. Systems approaches need to incorporate quantitative morphological, protein, mRNA and DNA data. A significant challenge for clinical implementation of systems pathology is how to optimize information available from tissue, which is frequently sub-optimal in quality and amount, and yet generate useful predictive models that work. The transition of histopathology to systems pathophysiology and the use of multiscale data sets usher in a new era in diagnosis, prognosis and prediction based on the analysis of human tissue. © 2013 The Authors. FEBS Journal published by John Wiley & Sons Ltd on behalf of FEBS.

  15. TAILS N-terminomic and proteomic datasets of healthy human dental pulp

    Directory of Open Access Journals (Sweden)

    Ulrich Eckhard

    2015-12-01

    Full Text Available The Data described here provide the in depth proteomic assessment of the human dental pulp proteome and N-terminome (Eckhard et al., 2015 [1]. A total of 9 human dental pulps were processed and analyzed by the positional proteomics technique TAILS (Terminal Amine Isotopic Labeling of Substrates N-terminomics. 38 liquid chromatography tandem mass spectrometry (LC-MS/MS datasets were collected and analyzed using four database search engines in combination with statistical downstream evaluation, to yield the by far largest proteomic and N-terminomic dataset of any dental tissue to date. The raw mass spectrometry data and the corresponding metadata have been deposited in ProteomeXchange with the PXD identifier ; Supplementary Tables described in this article are available via Mendeley Data (10.17632/555j3kk4sw.1.

  16. Dental pulp stem cells. Biology and use for periodontal tissue engineering.

    Science.gov (United States)

    Ashri, Nahid Y; Ajlan, Sumaiah A; Aldahmash, Abdullah M

    2015-12-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from their relative accessibility and pleasant handling properties. The purpose of this article is to review the biological principles of periodontal tissue engineering, along with the challenges facing the development of a consistent and clinically relevant tissue regeneration platform. This article includes an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors.

  17. Potential of human dental stem cells in repairing the complete transection of rat spinal cord

    Science.gov (United States)

    Yang, Chao; Li, Xinghan; Sun, Liang; Guo, Weihua; Tian, Weidong

    2017-04-01

    Objective. The adult spinal cord of mammals contains a certain amount of neural precursor cells, but these endogenous cells have a limited capacity for replacement of lost cells after spinal cord injury. The exogenous stem cells transplantation has become a therapeutic strategy for spinal cord repairing because of their immunomodulatory and differentiation capacity. In addition, dental stem cells originating from the cranial neural crest might be candidate cell sources for neural engineering. Approach. Human dental follicle stem cells (DFSCs), stem cells from apical papilla (SCAPs) and dental pulp stem cells (DPSCs) were isolated and identified in vitro, then green GFP-labeled stem cells with pellets were transplanted into completely transected spinal cord. The functional recovery of rats and multiple neuro-regenerative mechanisms were explored. Main results. The dental stem cells, especially DFSCs, demonstrated the potential in repairing the completely transected spinal cord and promote functional recovery after injury. The major involved mechanisms were speculated below: First, dental stem cells inhibited the expression of interleukin-1β to reduce the inflammatory response; second, they inhibited the expression of ras homolog gene family member A (RhoA) to promote neurite regeneration; third, they inhibited the sulfonylurea receptor1 (SUR-1) expression to reduce progressive hemorrhagic necrosis; lastly, parts of the transplanted cells survived and differentiated into mature neurons and oligodendrocytes but not astrocyte, which is beneficial for promoting axons growth. Significance. Dental stem cells presented remarkable tissue regenerative capability after spinal cord injury through immunomodulatory, differentiation and protection capacity.

  18. Interaction of ArF laser with dental hard tissue (AEM Study

    Directory of Open Access Journals (Sweden)

    Abbas Majdabadi

    2016-07-01

    Full Text Available Background and Aims: Nowadays lasers are used as alternatives to the tooth preparation because of reducing pain and bloodshed. The aim of this study was to observe the effect of ArF laser on the dental hard tissues. Materials and Methods: For this research human molar teeth with no caries or dental restoration and enamel cracks were used. Irradiation laser energies were taken 95, 70 and 50 mJ for enamel and 80, 70 and 50 mJ for dentine. Then, for each of energy values pulse numbers (repetition rate were adjusted at 200, 400, 600, 800, 1000 and 1500. Ablation was carried out without water spray on both enamel and dentine. Finally, the dimensions of ablated areas were measured by using a camera connected to the computer and results were applied in graphs. Results: For each energy value, the ablation dimension increased by increasing pulse numbers. Ablation depth in dentine was more than that of for enamel. Trends of graphs for dentine and enamel were the same. SEM images of ablations by 95 mJ energy on enamel and 80 mJ energy on dentine showed sharp edges. Conclusion: Ablation depths increased by increasing pulse numbers, for each energy level. However, this increase was not that as expected, because the lack of water spray while irradiating.

  19. Dental pulp stem cells immobilized in alginate microspheres for applications in bone tissue engineering.

    Science.gov (United States)

    Kanafi, M M; Ramesh, A; Gupta, P K; Bhonde, R R

    2014-07-01

    To immobilize dental pulp stem cells (DPSC) in alginate microspheres and to determine cell viability, proliferation, stem cell characteristics and osteogenic potential of the immobilized DPSCs. Human DPSCs isolated from the dental pulp were immobilized in 1% w/v alginate microspheres. Viability and proliferation of immobilized DPSCs were determined by trypan blue and MTT assay, respectively. Stem cell characteristics of DPSCs post immobilization were verified by labelling the cells with CD73 and CD90. Osteogenic potential of immobilized DPSCs was assessed by the presence of osteocalcin. Alizarin red staining and O-cresolphthalein complexone method confirmed and quantified calcium deposition. A final reverse transcriptase PCR evaluated the expression of osteogenic markers - ALP, Runx-2 and OCN. More than 80% of immobilized DPSCs were viable throughout the 3-week study. Proliferation appeared controlled and consistent unlike DPSCs in the control group. Presence of CD73 and CD90 markers confirmed the stem cell nature of immobilized DPSCs. The presence of osteocalcin, an osteoblastic marker, was confirmed in the microspheres on day 21. Mineralization assays showed high calcium deposition indicating elevated osteogenic potential of immobilized DPSCs. Osteogenic genes- ALP, Runx-2 and OCN were also upregulated in immobilized DPSCs. Surprisingly, immobilized DPSCs in the control group cultured in conventional stem cell media showed upregulation of osteogenic genes and expressed osteocalcin. Dental pulp stem cells immobilized in alginate hydrogels exhibit enhanced osteogenic potential while maintaining high cell viability both of which are fundamental for bone tissue regeneration. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. Effect of irradiation on the dental pulp tissues in streptozotocin-induced diabetic rats

    International Nuclear Information System (INIS)

    Kang, Ho Duk; Hwang, Eui Hwan; Lee, Sang Rae

    2005-01-01

    To observe the histological changes in the pulp tissues of mandibular molars in streptozotocin-induced diabetic rats after irradiation. The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups : control, diabetes, irradiation, and diabetes-irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes-irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. In the diabetes group, capillary dilatation was observed. However, there was no obvious morphologic alteration of the odontoblasts. In the irradiation group, generalized necrosis of the dental pulp tissues was observed. Vacuolation of the odontoblasts and dilatation of the capillaries were noted in the early experimental phases. In the diabetes-irradiation group, generalized degeneration of the dental pulp tissues was observed. Vacuolation of the dental pulp cells and the odontoblasts was noted in the late experimental phases. This experiment suggest that dilatation of the capillaries in the dental pulp tissue is induced by diabetic state, and generalized degeneration of the dental pulp tissues is induced by irradiation of the diabetic group.

  1. Dental Practice, Human Immunodeficiency Virus Transmission and ...

    African Journals Online (AJOL)

    by blood and blood products essentially occur through the use ... occupational risks and questions on the attitudes of the ... No response. 6 ... Figure 3: Dental professionals have a lower risk of being infected with .... Greeff M, Phetlhu R. The meaning and effect of HIV/AIDS .... For the purpose of printing, always retain a good.

  2. Dental Practice, Human Immunodeficiency Virus Transmission and ...

    African Journals Online (AJOL)

    A self-administered questionnaire was used for data collection. A total of 113 OHCWs comprising students, house officers, resident doctors, dental nurses and consultants participated. Analysis was by Statistical Package for the Social Sciences version 17 (SPSS Inc., Chicago, IL, USA). Data analysis included descriptive ...

  3. Characterization of inflammatory cell infiltrate in human dental pulpitis.

    Science.gov (United States)

    Bruno, K F; Silva, J A; Silva, T A; Batista, A C; Alencar, A H G; Estrela, C

    2010-11-01

    To evaluate the microscopic characteristics and densities (per mm(2) ) of tryptase(+) mast cells, CD4(+) T helper lymphocytes, CD45RO(+) memory T lymphocytes, foxp3(+) T regulatory lymphocytes, CD20(+) B lymphocytes, CD68(+) macrophages, and CD31(+) blood vessels in human dental pulpitis (n=38) and healthy pulpal tissue (n=6). The pulps of 38 human teeth with a clinical diagnosis of irreversible pulpitis were removed by pulpectomy. The pulp tissue was immersed in 10% buffered formalin for evaluation using light microscopy. Tryptase, CD4, CD45RO, foxp3, CD20, CD68, and CD31 expressions were analysed using immunohistochemistry; other microscopic features, such as intensity of inflammatory infiltrate and collagen deposition, were evaluated using haematoxylin and eosin stain. Wilcoxon and Mann-Whitney tests were used for statistical analysis. The significance level was set at α=5%. Two microscopic patterns of pulpitis were found: group 1 (G1) (n=15) had an intense inflammatory infiltrate and mild collagen deposition; conversely, group 2 (G2) (n=23) had a scarce inflammatory infiltrate and intense collagen deposition. The numbers of CD68(+) macrophages (P=0.004) and CD20(+) B (P=0.068) lymphocytes and the density of blood vessels (P=0.002) were higher in G1 than in G2. However, a similar number of CD4(+) and CD45RO(+) T lymphocytes was found in both groups (P>0.05). When present, tryptase(+) mast cells were equally distributed in G1 and G2, whereas foxp3(+) T regulatory lymphocytes were detected in 59% and 14% of the samples of G1 and G2. Controls exhibited lower numbers of foxp3, tryptase, CD4, CD45RO, CD68 and CD20 positive cells than G1 and G2. Irreversible pulpitis had distinct microscopic features with important quantitative and qualitative differences in inflammatory cell infiltration. © 2010 International Endodontic Journal.

  4. SEM evaluation of the morphological changes in hard dental tissues prepared by Er: YAG laser and rotary instruments

    Directory of Open Access Journals (Sweden)

    Tomov Georgi

    2010-09-01

    Full Text Available Effective ablation of dental hard tissues by means of the erbium:yttrium-aluminum garnet (Er: YAG laser has been reported recently, and its application to caries removal and cavity preparation has been expected. However, few studies have investigated the morphological changes in hard dental tissues after Er: YAG laser caries treatment. In the present study the morphological changes in hard dental tissues after Er: YAG laser caries ablation in vitro was compared with that of conventional mechanical treatment. Thirty extracted human teeth with caries were used. Ten tooth was treated with the Er: YAG laser, and the other was treated with a conventional steel and diamond burs. Laser treatment was performed by means of a non-contact irradiation modes with cooling water spray, with a new Er: YAG laser (LiteTouch. Conventional bur treatment was conducted by means of a low-speed micromotor and air turbine with water cooling. Scanning electron microscope (SEM observations were performed for each treatment. The Er: YAG laser ablated carious dentin effectively with minimal thermal damage to the surrounding intact dentin, and removed infected and softened carious dentin to the same degree as the burtreatment. In addition, a lower degree of vibration was noted with the Er: YAG laser treatment. The SEM examination revealed characteristic micro-irregularities of the lased dentin and enamel surfaces with potential benefits for adhesive restorations. Our results show that the Er: YAG laser is promising as a new technical modality for caries treatment

  5. Different expressions of connexin 43 and 32 in the fibroblasts of human dental pulp.

    Science.gov (United States)

    Ibuki, N; Yamaoka, Y; Sawa, Y; Kawasaki, T; Yoshida, S

    2002-06-01

    The expression and localization of gap junctional proteins connexin (Cx) 26, 32, and 43 was examined in human dental pulp. Dental pulp tissues were obtained from human third molars immediately after extraction. Some pulp tissues were used for cell culture, and the rest for histological observations. Immunostaining for cultured dental pulp fibroblasts (DPFs) showed that Cx32 and 43 were expressed in human DPFs, and proteins corresponding to 27 (Cx32) and 43kDa (Cx43) were identified by Western blot analysis. Immunostaining for tissue sections showed that the expression of Cx32 and 43 was observed in the entire region of the pulp and further strong expression of Cx32 was established beneath the cell-rich zone. Considering the close relationship between Cx types and cell functions, the results indicate that DPFs beneath the cell-rich zone may have specific, Cx32-related functions. The cell rich zone is thought to contain progenitor odontoblasts that can be induced to differentiate into mature odontoblasts in response to wounding. Therefore, it may be hypothesized that DPFs just beneath the cell-rich zone produce proteins and induce odontoblast differentiation from the cells in the cell-rich zone.

  6. Direct evidence of milk consumption from ancient human dental calculus

    DEFF Research Database (Denmark)

    Warinner, C.; Hendy, J.; Speller, C.

    2014-01-01

    directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG...... is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up...

  7. Cryopreserved Dental Pulp Tissues of Exfoliated Deciduous Teeth Is a Feasible Stem Cell Resource for Regenerative Medicine

    Science.gov (United States)

    Yamaza, Haruyoshi; Akiyama, Kentaro; Hoshino, Yoshihiro; Song, Guangtai; Kukita, Toshio; Nonaka, Kazuaki; Shi, Songtao; Yamaza, Takayoshi

    2012-01-01

    Human exfoliated deciduous teeth have been considered to be a promising source for regenerative therapy because they contain unique postnatal stem cells from human exfoliated deciduous teeth (SHED) with self-renewal capacity, multipotency and immunomodulatory function. However preservation technique of deciduous teeth has not been developed. This study aimed to evaluate that cryopreserved dental pulp tissues of human exfoliated deciduous teeth is a retrievable and practical SHED source for cell-based therapy. SHED isolated from the cryopreserved deciduous pulp tissues for over 2 years (25–30 months) (SHED-Cryo) owned similar stem cell properties including clonogenicity, self-renew, stem cell marker expression, multipotency, in vivo tissue regenerative capacity and in vitro immunomodulatory function to SHED isolated from the fresh tissues (SHED-Fresh). To examine the therapeutic efficacy of SHED-Cryo on immune diseases, SHED-Cryo were intravenously transplanted into systemic lupus erythematosus (SLE) model MRL/lpr mice. Systemic SHED-Cryo-transplantation improved SLE-like disorders including short lifespan, elevated autoantibody levels and nephritis-like renal dysfunction. SHED-Cryo amended increased interleukin 17-secreting helper T cells in MRL/lpr mice systemically and locally. SHED-Cryo-transplantation was also able to recover osteoporosis bone reduction in long bones of MRL/lpr mice. Furthermore, SHED-Cryo-mediated tissue engineering induced bone regeneration in critical calvarial bone-defect sites of immunocompromised mice. The therapeutic efficacy of SHED-Cryo transplantation on immune and skeletal disorders was similar to that of SHED-Fresh. These data suggest that cryopreservation of dental pulp tissues of deciduous teeth provide a suitable and desirable approach for stem cell-based immune therapy and tissue engineering in regenerative medicine. PMID:23251621

  8. Human dental pulp stem cells with highly angiogenic and neurogenic potential for possible use in pulp regeneration.

    Science.gov (United States)

    Nakashima, Misako; Iohara, Koichiro; Sugiyama, Masahiko

    2009-01-01

    Dental caries is a common public health problem, causing early loss of dental pulp and resultant tooth loss. Dental pulp has important functions to sustain teeth providing nutrient and oxygen supply, innervation, reactionary/reparative dentin formation and immune response. Regeneration of pulp is an unmet need in endodontic therapy, and angiogenesis/vasculogenesis and neurogenesis are critical for pulp regeneration. Permanent and deciduous pulp tissue is easily available from teeth after extraction without ethical issues and has potential for clinical use. In this review, we introduce some stem cell subfractions, CD31(-)/CD146(-) SP cells and CD105(+) cells with high angiogenic and neurogenic potential, derived from human adult dental pulp tissue. Potential utility of these cells is addressed as a source of cells for treatment of cerebral and limb ischemia and pulp inflammation complete with angiogenesis and vasculogenesis.

  9. Uranium content and U-Th dating of fossil bones and dental tissues from Lazaret cave

    International Nuclear Information System (INIS)

    Michel, V.; Falgueres, Ch.; Yokoyama, Y.

    1997-01-01

    Fossil bone and dental tissues from Lazaret cave and modern ones are here the subject of a comparative microscopical study. Porous tissues such as dentine and bone have retained their Haversian and Tomes canals respectively. However, cracked areas with calcite were detected, indicating a water percolation within porous tissues and an alteration of tissue in places. In addition, compact fossil enamel is particularly well preserved. These results are essential for U-Tb and ESR dating application. Uranium contents, U-Tb ages of two fossil mandibular tissues, two tibias and of six burnt fossil bones are presented and discussed. (authors)

  10. Variation in alternative splicing across human tissues

    OpenAIRE

    Yeo, Gene; Holste, Dirk; Kreiman, Gabriel; Burge, Christopher B

    2004-01-01

    Background: Alternative pre-mRNA splicing (AS) is widely used by higher eukaryotes to generate different protein isoforms in specific cell or tissue types. To compare AS events across human tissues, we analyzed the splicing patterns of genomically aligned expressed sequence tags (ESTs) derived from libraries of cDNAs from different tissues. Results: Controlling for differences in EST coverage among tissues, we found that the brain and testis had the highest levels of exon skipping. The most p...

  11. The importance of the biomimetic composites components for recreating the optical properties and molecular composition of intact dental tissues.

    Science.gov (United States)

    Seredin, P. V.; Goloshchapov, D. L.; Gushchin, M. S.; Ippolitov, Y. A.; Prutskij, T.

    2017-11-01

    The objective of this paper was to investigate whether it is possible to obtain biomimetic materials recreating the luminescent properties and molecular composition of intact dental tissues. Biomimetic materials were produced and their properties compared with native dental tissues. In addition, the overall contribution of the organic and non-organic components in the photoluminescence band was investigated. The results showed that it is possible to develop biomimetic materials with similar molecular composition and optical properties to native dental tissues for the early identification of dental caries.

  12. Baring the teeth. [Dental caries and the analysis of trace elements in dental tissues

    Energy Technology Data Exchange (ETDEWEB)

    Cleaton-Jones, P [University of the Witwatersrand, Johannesburg (South Africa). Dental Research Unit; Retief, H [Alabama Univ., Birmingham (USA); Turkstra, J [Fort Hare Univ. (South Africa). Dept. of Chemistry

    1979-07-01

    To determine whether trace elements other than fluorine play a role in the varying prevalences of dental caries in different South African population groups, neutron activation techniques have been devised to establish the concentrations of trace elements in tooth enamel and dentine.

  13. Theory analysis of the Dental Hygiene Human Needs Conceptual Model.

    Science.gov (United States)

    MacDonald, L; Bowen, D M

    2017-11-01

    Theories provide a structural knowing about concept relationships, practice intricacies, and intuitions and thus shape the distinct body of the profession. Capturing ways of knowing and being is essential to any professions' practice, education and research. This process defines the phenomenon of the profession - its existence or experience. Theory evaluation is a systematic criterion-based assessment of a specific theory. This study presents a theory analysis of the Dental Hygiene Human Needs Conceptual Model (DH HNCM). Using the Walker and Avant Theory Analysis, a seven-step process, the DH HNCM, was analysed and evaluated for its meaningfulness and contribution to dental hygiene. The steps include the following: (i) investigate the origins; (ii) examine relationships of the theory's concepts; (iii) assess the logic of the theory's structure; (iv) consider the usefulness to practice; (v) judge the generalizability; (vi) evaluate the parsimony; and (vii) appraise the testability of the theory. Human needs theory in nursing and Maslow's Hierarchy of Need Theory prompted this theory's development. The DH HNCM depicts four concepts based on the paradigm concepts of the profession: client, health/oral health, environment and dental hygiene actions, and includes validated eleven human needs that evolved overtime to eight. It is logical, simplistic, allows scientific predictions and testing, and provides a unique lens for the dental hygiene practitioner. With this model, dental hygienists have entered practice, knowing they enable clients to meet their human needs. For the DH HNCM, theory analysis affirmed that the model is reasonable and insightful and adds to the dental hygiene professions' epistemology and ontology. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Detection for demineralization of dental hard tissues using index-sequenced radiographs

    International Nuclear Information System (INIS)

    Park, Dong Hyun; Park, Young Ho; Kim, Kyung Sook; Park, Jeong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Hun Kuk; Choi, Yong Suk; Hwang, Eui Hwan

    2009-01-01

    The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

  15. Detection for demineralization of dental hard tissues using index-sequenced radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Hyun; Park, Young Ho; Kim, Kyung Sook; Park, Jeong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, KyungHee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, KyungHee University, Seoul (Korea, Republic of)

    2009-06-15

    The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

  16. Cryobanking of human ovarian tissue

    DEFF Research Database (Denmark)

    Ernst, Erik; Andersen, Anders Nyboe; Andersen, Claus Yding

    2014-01-01

    Cryopreservation of ovarian tissue is one way of preserving fertility in young women with a malignant disease or other disorders that require gonadotoxic treatment. The purpose of the study was to explore how many women remained interested in continued cryostorage of their ovarian tissue beyond...... an initial 5-year period. Between 1999 and 2006, a total of 201 girls and young women had one ovary cryopreserved for fertility preservation in Denmark. One hundred of these met our inclusion criteria, which included a follow-up period of at least 5 years, and were mailed a questionnaire. The response rate...... women with ovarian tissue cryobanked requested continued cryostorage after an initial period of at least 5 years. The main reason for requesting disposal was successful completion of a family....

  17. The influence of parotid gland sparing on radiation damages of dental hard tissues.

    Science.gov (United States)

    Hey, Jeremias; Seidel, Johannes; Schweyen, Ramona; Paelecke-Habermann, Yvonne; Vordermark, Dirk; Gernhardt, Christian; Kuhnt, Thomas

    2013-07-01

    The aim of the present study was to evaluate whether radiation damage on dental hard tissue depends on the mean irradiation dose the spared parotid gland is subjected to or on stimulated whole salivary flow rate. Between June 2002 and October 2008, 70 patients with neck and cancer curatively irradiated were included in this study. All patients underwent dental treatment referring to the guidelines and recommendations of the German Society of Dental, Oral and Craniomandibular Sciences prior, during, and after radiotherapy (RT). During the follow-up period of 24 months, damages on dental hard tissues were classified according to the RTOG/EORTC guidelines. The mean doses (D(mean)) during spared parotid gland RT were determined. Stimulated whole saliva secretion flow rates (SFR) were measured before RT and 1, 6, 12, 24 months after RT. Thirty patients showed no carious lesions (group A), 18 patients developed sporadic carious lesions (group B), and 22 patients developed general carious lesions (group C). Group A patients received a D mean of 21.2 ± 11.04 Gy. Group B patients received a D(mean) of 26.5 ± 11.59 Gy and group C patients received a D(mean) of 33.9 ± 9.93 Gy, respectively. The D(mean) of group A was significantly lower than the D(mean) of group C (p dental hard tissue correlates with increased mean irradiation doses as well as decreased salivary flow rates. Parotid gland sparing resulting in a dose below 20 Gy reduces radiation damage on dental hard tissues, and therefore, the dose may act as a predictor for the damage to be expected.

  18. Hard tissue formation of STRO-1-selected rat dental pulp stem cells in vivo.

    NARCIS (Netherlands)

    Yang, X.; Walboomers, X.F.; Beucken, J.J.J.P van den; Bian, Z.; Fan, M.; Jansen, J.A.

    2009-01-01

    The objective of this study was to examine hard tissue formation of STRO-1-selected rat dental pulp-derived stem cells, seeded into a calcium phosphate ceramic scaffold, and implanted subcutaneously in mice. Previously, STRO-1 selection was used to obtain a mesenchymal stem cell progenitor

  19. A study of tooth brushing pattern and its effects on dental tissues in ...

    African Journals Online (AJOL)

    The prevalence of non carious cervical lesion was 3% and these lesions were found in males only. Conclusion: The pattern of tooth brushing was correct in 51.7% of the respondents as reported. However the effect on dental tissues though present is not exaggerated when compared to other studies done in other parts of ...

  20. Viscoelastic Properties of Dental Pulp Tissue and Ramifications on Biomaterial Development for Pulp Regeneration.

    Science.gov (United States)

    Erisken, Cevat; Kalyon, Dilhan M; Zhou, Jian; Kim, Sahng G; Mao, Jeremy J

    2015-10-01

    A critical step in biomaterial selection effort is the determination of material as well as the biological properties of the target tissue. Previously, the selection of biomaterials and carriers for dental pulp regeneration has been solely based on empirical experience. In this study, first, the linear viscoelastic material functions and compressive properties of miniature pig dental pulp were characterized using small-amplitude oscillatory shear and uniaxial compression at a constant rate. They were then compared with the properties of hydrogels (ie, agarose, alginate, and collagen) that are widely used in tissue regeneration. The comparisons of the linear viscoelastic material functions of the native pulp tissue with those of the 3 hydrogels revealed the gel-like behavior of the pulp tissue over a relatively large range of time scales (ie, over the frequency range of 0.1-100 rps). At the constant gelation agent concentration of 2%, the dynamic properties (ie, storage and loss moduli and the tanδ) of the collagen-based gel approached those of the native tissue. Under uniaxial compression, the peak normal stresses and compressive moduli of the agarose gel were similar to those of the native tissue, whereas alginate and collagen exhibited significantly lower compressive properties. The linear viscoelastic and uniaxial compressive properties of the dental pulp tissue reported here should enable the more appropriate selection of biogels for dental pulp regeneration via the better tailoring of gelation agents and their concentrations to better mimic the dynamic and compressive properties of native pulp tissue. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Antifungal Effect of a Dental Tissue Conditioner Containing Nystatin-Loaded Alginate Microparticles.

    Science.gov (United States)

    Kim, Hyun-Jin; Son, Jun Sik; Kwon, Tae-Yub

    2018-02-01

    In this in vitro study, nystatin-alginate microparticles were successfully fabricated to control the release of nystatin from a commercial dental tissue conditioner. These nystatin-alginate microparticles were spherical and had a slightly rough surface. The microparticles incorporated into the tissue conditioner were distributed homogeneously throughout the tissue conditioner matrix. The incorporation of the microparticles did not deteriorate the mechanical properties of the original material. The agar diffusion test results showed that the tissue conditioner containing the microparticles had a good antifungal effect against Candida albicans. The nystatin-alginate microparticles efficiently controlled the release of nystatin from the tissue conditioner matrix over the experimental period of 14 days. Moreover, the nystatin-alginate microparticles incorporated in the tissue conditioner showed effective antifungal function even at lower concentrations of nystatin. The current study suggests that the tissue conditioner containing the nystatin-alginate microparticle carrier system has potential as an effective antifungal material.

  2. NCI’s Cooperative Human Tissue Network

    Science.gov (United States)

    Quality biospecimens are a foundational resource for cancer research. One of NCI’s longest running biospecimen programs is the Cooperative Human Tissue Network, a resource mainly for basic discovery and early translational research.

  3. Construction of retroviral recombinant containing human tissue ...

    African Journals Online (AJOL)

    USER

    2010-03-29

    Mar 29, 2010 ... Recombinant retroviral vector containing human tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) gene was ..... heavy metal ions, the protein could be express in an .... involves adhesion, degradation and movement. To.

  4. Influence of different types of light on the response of the pulp tissue in dental bleaching: a systematic review.

    Science.gov (United States)

    Benetti, Francine; Lemos, Cleidiel Aparecido Araújo; de Oliveira Gallinari, Marjorie; Terayama, Amanda Miyuki; Briso, André Luiz Fraga; de Castilho Jacinto, Rogério; Sivieri-Araújo, Gustavo; Cintra, Luciano Tavares Angelo

    2018-05-01

    This systematic review (PROSPERO register: CRD42016053140) investigated the influence of different types of light on the pulp tissue during dental bleaching. Two independent authors conducted a systematic search and risk of bias evaluations. An electronic search was undertaken (PubMed/Medline, Embase, The Cochrane Library, and other databases) until May 2017. The population, intervention, comparison, outcomes (PICO) question was: "Does the light in dental bleaching change the response of the pulp to the bleaching procedure?" The intervention involved pulp tissue/cells after bleaching with light, while the comparison involved pulp tissue/cells after bleaching without light. The primary outcome was the inflammation/cytotoxicity observed in pulp after bleaching. Out of 2210 articles found, 12 articles were included in the review; four were in vivo studies (one study in dogs/others in human), and eight were in vitro studies (cell culture/with artificial pulp chamber or not). The light source used was halogen, light-emitting diode (LED), and laser. Only one in vivo study that used heat to simulate light effects showed significant pulp inflammation. Only two in vitro studies demonstrated that light influenced cell metabolism; one using halogen light indicated negative effects, and the other using laser therapy indicated positive effects. Given that animal and in vitro studies have been identified, there remain some limitations for extrapolation to the human situation. Furthermore, different light parameters were used. The effects of dental bleaching on the pulp are not influenced by different types of light, but different light parameters can influence these properties. There is insufficient evidence about the influence of different types of light on inflammation/cytotoxicity of the pulp.

  5. Anisotropic local physical properties of human dental enamel in comparison to properties of some common dental filling materials.

    Science.gov (United States)

    Raue, Lars; Hartmann, Christiane D; Rödiger, Matthias; Bürgers, Ralf; Gersdorff, Nikolaus

    2014-11-01

    A major aspect in evaluating the quality of dental materials is their physical properties. Their properties should be a best fit of the ones of dental hard tissues. Manufacturers give data sheets for each material. The properties listed are characterized by a specific value. This assumes (but does not prove) that there is no direction dependence of the properties. However, dental enamel has direction-dependent properties which additionally vary with location in the tooth. The aim of this paper is to show the local direction dependence of physical properties like the elastic modulus or the thermal expansion in dental hard tissues. With this knowledge the 'perfect filling/dental material' could be characterized. Enamel sections of ∼400-500 μm thickness have been cut with a diamond saw from labial/buccal to palatal/lingual (canine, premolar and molar) and parallel to labial (incisor). Crystallite arrangements have been measured in over 400 data points on all types of teeth with x-ray scattering techniques, known from materials science. X-ray scattering measurements show impressively that dental enamel has a strong direction dependence of its physical properties which also varies with location within the tooth. Dental materials possess only little or no property direction dependence. Therefore, a mismatch was found between enamel and dental materials properties. Since dental materials should possess equal (direction depending) properties, worthwhile properties could be characterized by transferring the directional properties of enamel into a property 'wish list' which future dental materials should fulfil. Hereby the 'perfect dental material' can be characterized.

  6. Dental histology of Coelophysis bauri and the evolution of tooth attachment tissues in early dinosaurs.

    Science.gov (United States)

    Fong, Raymond K M; LeBlanc, Aaron R H; Berman, David S; Reisz, Robert R

    2016-07-01

    Studies of dinosaur teeth have focused primarily on external crown morphology and thus, use shed or in situ tooth crowns, and are limited to the enamel and dentine dental tissues. As a result, the full suites of periodontal tissues that attach teeth to the jaws remain poorly documented, particularly in early dinosaurs. These tissues are an integral part of the tooth and thus essential to a more complete understanding of dental anatomy, development, and evolution in dinosaurs. To identify the tooth attachment tissues in early dinosaurs, histological thin sections were prepared from the maxilla and dentary of a partial skull of the early theropod Coelophysis bauri from the Upper Triassic (Rhaetian- 209-201 Ma) Whitaker Quarry, New Mexico, USA. As one of the phylogenetically and geologically oldest dinosaurs, it is an ideal candidate for examining dental tissues near the base of the dinosaurian clade. The teeth of C. bauri exhibited a fibrous tooth attachment in which the teeth possessed five tissues: enamel, dentine, cementum, periodontal ligament (PDL), and alveolar bone. Our findings, coupled with those of more recent studies of ornithischian teeth, indicate that a tripartite periodontium, similar to that of crocodilians and mammals, is the plesiomorphic condition for dinosaurs. The occurrence of a tripartite periodontium in dinosaurs adds to the growing consensus that the presence of these tissues is the plesiomorphic condition for the major amniote clades. Furthermore, this study establishes the relative timing of tissue development and growth directions of periodontal tissues and provides the first comparative framework for future studies of dinosaur periodontal development, tooth replacement, and histology. J. Morphol. 277:916-924, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Clonality evaluation in human tissues

    Directory of Open Access Journals (Sweden)

    Villamizar-Rivera, Nicolás

    2015-07-01

    Full Text Available Malignant proliferations are usually clonal. While most times the biological potential can be established through routine pathologic and clinical examinations, some cases are difficult to classify. Moreover, in some situations there are dominant clones whose analysis is important, such as in autoimmune diseases and immunodeficiency. This paper presents in an understandable way the main techniques for the study of clonality, namely: evaluation of gene rearrangements of antigen receptor, and evaluation of human antigen receptor gene.

  8. Ultrastructural study of tissues surrounding replanted teeth and dental implants.

    Science.gov (United States)

    Shioya, Kazuhiro; Sawada, Takashi; Miake, Yasuo; Inoue, Sadayuki; Yanagisawa, Takaaki

    2009-03-01

    The aim of this study was to describe the ultrastructure of the dentogingival border at replanted teeth and implants. Wistar rats (8 weeks old) were divided into groups for replantation and implantation experiments. In the former, the upper right first molars were extracted and then immediately replanted. In the latter, pure titanium implants were used. All tissues were fixed, demineralized and embedded in epoxy resin for ultrastructural observations. One week after replantation, the junctional epithelium was lost, and the oral sulcular epithelium covered the enamel surface. The amount of the epithelium increased in 2 weeks, and resembled the junctional epithelium, and the internal basal lamina and hemidesmosomes were formed in 4 weeks. One week after implantation, peri-implant epithelium was formed, and in 2 and 4 weeks, this epithelium with aggregated connective tissue cells were observed. In 8 weeks, the peri-implant epithelium receded, and aligned special cells with surrounding elongated fibroblasts and bundles of collagen fibers appeared to seal the implant interface. In replantation of the tooth, the internal basal lamina remained at the surface of the enamel of the replanted tooth, which is likely to be related to regeneration of the junctional epithelium and the attachment apparatus at the epithelium-tooth interface. Following implantation, a layer of cells with characteristics of connective tissue cells, but no junctional epithelium and attachment apparatus, was formed to seal the site of the implant.

  9. Experimental investigation on the caries characteristic of dental tissues by photothermal radiometry scanning imaging

    Science.gov (United States)

    Wang, Fei; Liu, Jun-yan; Wang, Xiao-chun; Wang, Yang

    2018-03-01

    In this paper, a one-dimensional (1D) thermal-wave model coupled diffuse-photon-density-wave for three-layer dental tissues using modulated laser stimulation was employed to illustrate the relationship between dental caries characteristic (i.e. caries layer thickness, optical absorption coefficient and optical scattering coefficient) and photothermal radiometry (PTR) signal. Experimental investigation of artificial caries was carried out using PTR scanning imaging. The PTR amplitude and phase delay were increased with dental demineralized treatment. The local caries characteristic parameters were obtained by the best-fitting method based on the 1D thermal-wave model. The PTR scanning imaging measurements illustrated that the optical absorption coefficient and scattering coefficient of caries region were much higher than those of the healthy enamel area. The demineralization thickness of caries region was measured by PTR scanning imaging and its average value shows in good agreement with the digital microscope. Experimental results show that PTR scanning imaging has the merits of high contrast for local inhomogeneity of dental caries; furthermore, this method is an allowance to provide a flexibility for non-contact quantitative evaluation of dental caries.

  10. Putative Stem Cells in Human Dental Pulp with Irreversible Pulpitis-An Exploratory Study

    Science.gov (United States)

    Wang, Z.; Pan, J.; Wright, JT; Bencharit, S.; Zhang, S.; Everett, ET; Teixeira, FB; Preisser, JS

    2010-01-01

    Introduction Although human dental pulp stem cells isolated from healthy teeth have been extensively characterized, it is unknown whether stem cells also exist in clinically compromised teeth with irreversible pulpitis. Here we explored whether cells retrieved from clinically compromised dental pulp have stem cell-like properties. Methods Pulp cells were isolated from healthy teeth (control group) and from teeth with clinically diagnosed irreversible pulpitis (diseased group). Cell proliferation, stem cell marker STRO-1 expression and cell odonto-osteo-genic differentiation competence were compared. Results Cells from the diseased group demonstrated decreased colony formation capacity and a slightly decreased cell proliferation rate but had similar STRO-1 expression, and exhibited a similar percentage of positive ex vivo osteogenic induction and dentin sialophosphoprotein expression from STRO-1-enriched pulp cells. Conclusion Our study provides preliminary evidence that clinically compromised dental pulp may contain putative cells with certain stem cell properties. Further characterization of these cells will provide insight regarding whether they could serve as a source of endogenous multipotent cells in tissue regeneration based dental pulp therapy. PMID:20416426

  11. The effect of gastric juice on the development of erosive changes in hard dental tissue

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    Stojšin Ivana

    2014-01-01

    Full Text Available Introduction. Gastroesophageal reflux disease (GERD is an esophageal disorder where the refluxed gastric contents enters first into the esophagus followed by the pharynx, oral cavity, larynx, airway and middle ear, causing a range of disorders and symptoms. Hydrochloric acid from the gastric contents is responsible for the demineralization of dental hard tissues and release of matrix metalloproteinase from the dentin. Objective. The aim of this study was to verify the SEM (scanning electron microscopy analysis of the surface enamel, the enamel-dentin border and dentine after the exposure of intact teeth to filtrate of gastric contents obtained during routine endoscopy. Methods. Material used in the research was 10 extracted human impacted third molars. The coronal part of the tooth was divided into two parts, and then the two halves of teeth were exposed to the filtrate of gastric juice obtained during routine gastroscopy, which had been frozen until the moment of the experiment initiation. All samples of teeth were immersed in the filtrate of the content at a temperature of 20°C for 60 minutes. The prepared samples were observed by the SEM in the area of the enamel, the enamel-dentin border and in the area of dentin at different magnification. Results. The SEM analysis showed that both enamel and dentin had a significant demineralization of these tissues. Enamel surface resembled a demineralization similar to that of acid conditioning before the application of composite restorations. The degree of mineralization was more intense towards the enamel - dentin border, and at this area the enamel prisms were not fully recognizable. The dentin had a complete loss of peritubular dentin, the entry points of the dentin tubules were expanded and intertubular dentin demineralization was also registered. Conclusion. SEM analysis showed a significant degree of destruction of enamel and dentin. Significant changes in the surface structure of enamel and

  12. Successful isolation, in vitro expansion and characterization of stem cells from Human Dental Pulp

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    Preethy SP

    2010-01-01

    Full Text Available BACKGROUND: Recent studies have shown that mesenchymal stem cells isolated from post natal human dental pulp, (Dental pulp stem cells-DPSCs which is from permanent teeth and SHED (stem cells from human exfoliated deciduous teeth,the Periodontal ligament stem cells (PDLSC and Stem cells from root Apical papilla(SCAPhave the potential to differentiate into cells of a variety of tissues including heart, muscle, cartilage, bone, nerve, salivary glands, teeth etc(1,2,3,4.This multipotential ability of DPSCs is being researched for clinical application for treating a variety of diseases like myocardial infarction, muscular dystrophy, neuro-degenerative disorders, cartilage replacement, tooth regeneration and for repair of bone defects to mention a few. Moreover, the isolation of stem cells from teeth is minimally invasive, readily accessible and the non immunogenic characteristic of dental stem cells has paved the way for efforts to store the exfoliated deciduous teeth or milk teeth which is usually discarded, for use in the future. In this study we have isolated and expanded in vitro, the cells obtained from human dental pulp. MATERIALS AND METHODS: After obtaining written informed consent, 24 teeth that were extracted for therapeutic or cosmetic reasons from 16 patients were used in this study. The specimens were transported from the clinic to NCRM lab taking 6 to 48 Hrs. For removal of the pulp tissue, the teeth were split obliquely at the Cementoenamel junction and the pulp tissue was isolated using brooches. The extracted pulp tissues were subjected to digestion using Collagenase type-I and type II at 37˚C for 15- 30 minutes. The digested cells were filtered with 70µm filter and centrifuged at 1800 rpm for 10 minutes. The pellet was then suspended in Dulbecco’s modified Eagle’s medium (DMEM/Ham’s F12 supplemented with 15% fetal bovine serum , 100 U/ml penicillin, 100 µg/ml streptomycin,2 m M L -glutamine, and 2 m M nonessential amino

  13. Culture of human dental pulp cells at variable times post-tooth extraction

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    BENÍCIO Daniela Ferreira Araújo

    2018-02-01

    Full Text Available Abstract The aim of this study was to investigate the viability of human dental pulp cells from extracted teeth kept at standard room temperature and atmospheric pressure for different periods of time. Twenty-one healthy permanent teeth were used. They were divided into five groups according to the expected time from extraction to processing. One group was tested immediately after extraction; the other groups were each tested at one of the following time points: 30 minutes, 1 hour, 2 hours, and 5 hours post-extraction. Cell morphology was analysed by light microscopy; cell proliferation was analysed using MTT assay and by counting the viable cells in a haemocytometer. Similar results were observed in all groups (p < 0.05. A delay of up to five hours for tooth processing and tissue collection does not preclude the establishment of dental pulp cell cultures, affect the morphology of these cells, or reduce their proliferative potential.

  14. Human dental pulp cells exhibit bone cell-like responsiveness to fluid shear stress.

    Science.gov (United States)

    Kraft, David Christian Evar; Bindslev, Dorth Arenholt; Melsen, Birte; Klein-Nulend, Jenneke

    2011-02-01

    For engineering bone tissue to restore, for example, maxillofacial defects, mechanosensitive cells are needed that are able to conduct bone cell-specific functions, such as bone remodelling. Mechanical loading affects local bone mass and architecture in vivo by initiating a cellular response via loading-induced flow of interstitial fluid. After surgical removal of ectopically impacted third molars, human dental pulp tissue is an easily accessible and interesting source of cells for mineralized tissue engineering. The aim of this study was to determine whether human dental pulp-derived cells (DPC) are responsive to mechanical loading by pulsating fluid flow (PFF) upon stimulation of mineralization in vitro. Human DPC were incubated with or without mineralization medium containing differentiation factors for 3 weeks. Cells were subjected to 1-h PFF (0.7 ± 0.3 Pa, 5 Hz) and the response was quantified by measuring nitric oxide (NO) and prostaglandin E₂ (PGE₂) production, and gene expression of cyclooxygenase (COX)-1 and COX-2. We found that DPC are intrinsically mechanosensitive and, like osteogenic cells, respond to PFF-induced fluid shear stress. PFF stimulated NO and PGE₂ production, and up-regulated COX-2 but not COX-1 gene expression. In DPC cultured under mineralizing conditions, the PFF-induced NO, but not PGE₂, production was significantly enhanced. These data suggest that human DPC, like osteogenic cells, acquire responsiveness to pulsating fluid shear stress in mineralizing conditions. Thus DPC might be able to perform bone-like functions during mineralized tissue remodeling in vivo, and therefore provide a promising new tool for mineralized tissue engineering to restore, for example, maxillofacial defects.

  15. Application of the human needs conceptual model of dental hygiene to the role of the clinician : part II.

    Science.gov (United States)

    Walsh, M M; Darby, M

    1993-01-01

    In summary, the theories of Maslow and of Yura and Walsh have been highlighted as background for understanding the human needs conceptual model of dental hygiene. In addition, 11 human needs have been identified and defined as being especially related to dental hygiene care, and a sample evaluation tool for their clinical assessment and a dental hygiene care plan have been presented. The four concepts of client, environment, health/oral health, and dental hygiene actions explained in terms of human need theory, and the 11 human needs related to dental hygiene care constitute the human needs conceptual model of dental hygiene. Within the framework of the human needs conceptual model of dental hygiene, the dental hygiene process is a systematic approach to dental hygiene care that involves assessment of the 11 human needs related to dental hygiene care; analysis of deficits in these needs; determination of the dental hygiene care plan based on identified deficits; implementation of dental hygiene interventions stated in the care plan; and evaluation of the effectiveness of dental hygiene interventions in achieving specific goals, including subsequent reassessment and revision of the dental hygiene care plan. This human needs conceptual model for dental hygiene provides a guide for comprehensive and humanistic client care. This model allows the dental hygienist to view each client (whether an individual or a group) holistically to prevent oral disease and to promote health and wellness. Dental hygiene theorists are encouraged to expand this model or to develop additional conceptual models based on dental hygiene's paradigm.

  16. Adenovirus 36 DNA in human adipose tissue.

    Science.gov (United States)

    Ponterio, E; Cangemi, R; Mariani, S; Casella, G; De Cesare, A; Trovato, F M; Garozzo, A; Gnessi, L

    2015-12-01

    Recent studies have suggested a possible correlation between obesity and adenovirus 36 (Adv36) infection in humans. As information on adenoviral DNA presence in human adipose tissue are limited, we evaluated the presence of Adv36 DNA in adipose tissue of 21 adult overweight or obese patients. Total DNA was extracted from adipose tissue biopsies. Virus detection was performed using PCR protocols with primers against specific Adv36 fiber protein and the viral oncogenic E4orf1 protein nucleotide sequences. Sequences were aligned with the NCBI database and phylogenetic analyses were carried out with MEGA6 software. Adv36 DNA was found in four samples (19%). This study indicates that some individuals carry Adv36 in the visceral adipose tissue. Further studies are needed to determine the specific effect of Adv36 infection on adipocytes, the prevalence of Adv36 infection and its relationship with obesity in the perspective of developing a vaccine that could potentially prevent or mitigate infection.

  17. A First Step in De Novo Synthesis of a Living Pulp Tissue Replacement Using Dental Pulp MSCs and Tissue Growth Factors, Encapsulated within a Bioinspired Alginate Hydrogel.

    Science.gov (United States)

    Bhoj, Manasi; Zhang, Chengfei; Green, David W

    2015-07-01

    A living, self-supporting pulp tissue replacement in vitro and for transplantation is an attractive yet unmet bioengineering challenge. Our aim is to create 3-dimensional alginate-based microenvironments that replicate the shape of gutta-percha and comprise key elements for the proliferation of progenitor cells and the release of growth factors. An RGD-bearing alginate framework was used to encapsulate dental pulp stem cells and human umbilical vein endothelial cells in a ratio of 1:1. The alginate hydrogel also retained and delivered 2 key growth factors, vascular endothelial growth factor-121 and fibroblast growth factor, in a sufficient amount to induce proliferation. A method was then devised to replicate the shape of gutta-percha using RGD alginate within a custom-made mold of thermoresponsive N-isopropylacrylamide. Plugs of alginate containing different permutations of growth factor-based encapsulates were tested and evaluated for viability, proliferation, and release kinetics between 1 and 14 days. According to scanning electron microscopic and confocal microscopic observations, the encapsulated human endothelial cells and dental pulp stem cell distribution were frequent and extensive throughout the length of the construct. There were also high levels of viability in all test environments. Furthermore, cell proliferation was higher in the growth factor-based groups. Growth factor release kinetics also showed significant differences between them. Interestingly, the combination of vascular endothelial growth factor and fibroblast growth factor synergize to significantly up-regulate cell proliferation. RGD-alginate scaffolds can be fabricated into shapes to fill the pulp space by simple templating. The addition of dual growth factors to cocultures of stem cells within RGD-alginate scaffolds led to the creation of microenvironments that significantly enhance the proliferation of dental pulp stem cell/human umbilical vein endothelial cell combinations. Copyright

  18. Histological observation on dental hard tissue irradiated by ultrashort-pulsed laser

    Science.gov (United States)

    Uchizono, Takeyuki; Awazu, Kunio; Igarashi, Akihiro; Kato, Junji; Hirai, Yoshito

    2006-04-01

    In the field of dentistry, effectiveness of USPL irradiation is researched because USPL has less thermal side effect to dental hard tissue. In this paper, we observed morphological change and optical change of dental hard tissue irradiated by USPL for discussing the safety and effectiveness of USPL irradiation to dental hard tissues. Irradiated samples were crown enamel and root dentin of bovine teeth. Lasers were Ti:sapphire laser, which had pulse duration (P d)of 130 fsec and pulse repetition rate (f) of 1kHz and wavelength (l) of 800nm, free electron laser (FEL), which had P d of 15 μsec and f of 10Hz and wavelength of 9.6μm, and Er:YAG laser, which had P d of 250 μsec and f of 10Hz and wavelength of 2.94μm. After laser irradiation, the sample surfaces and cross sections were examined with SEM and EDX. The optical change of samples was observed using FTIR. In SEM, the samples irradiated by USPL had sharp and accurate ablation with no crack and no carbonization. But, in FEL and Er:YAG laser, the samples has rough ablation with crack and carbonization. It was cleared that the P/Ca ratio of samples irradiated by USPL had same value as non-irradiated samples. There was no change in the IR absorption spectrum between samples irradiated by USPL and non-irradiated sample. But, they of samples irradiated by FEL and Er:YAG laser, however, had difference value as non-irradiated samples. These results showed that USPL might be effective to ablate dental hard tissue without thermal damage.

  19. The effects of low level laser irradiation on proliferation of human dental pulp: a narrative review.

    Science.gov (United States)

    Staffoli, S; Romeo, U; Amorim, R N S; Migliau, G; Palaia, G; Resende, L; Polimeni, A

    2017-01-01

    Mesenchymal stem cells (MSCs) have the capability for self-renewal, proliferation, and differentiation in various types of specialized cells, so they are very important in cellular therapies. MSC from dental pulp are simply obtainable and have high proliferative capability. Among the therapies that can stimulate the proliferation of certain cell types, low-level laser therapy (LLLT) stands out. The target of this study is to perform a literature review to investigate these effects of low-level laser irradiation on proliferation of human dental pulp.The electronic search of scientific papers was conducted in the Lilacs, Scielo, Medline and PubMed databases through scientific articles published in national and international journals in the past 20 years.The results of this review suggest that LLLT may be a useful and important tool for future advances in cell therapy and tissue engineering associated to stem cells. Studies on cell therapy for regenerating dental tissues has already been done, and shows promising results.

  20. Human dental pulp cell culture and cell transplantation with an alginate scaffold.

    Science.gov (United States)

    Kumabe, Shunji; Nakatsuka, Michiko; Kim, Gi-Seup; Jue, Seong-Suk; Aikawa, Fumiko; Shin, Je-Won; Iwai, Yasutomo

    2006-02-01

    Many studies on tissue stem cells have been conducted in the field of regenerative medicine, and some studies have indicated that cultured dental pulp mesenchymal cells secrete dentin matrix. In the present study we used alginate as a scaffold to transplant subcultured human dental pulp cells subcutaneously into the backs of nude mice. We found that when beta-glycerophosphate was added to the culture medium, dentin sialophosphoprotein mRNA coding dentin sialoprotein (DSP) was expressed. An increase in alkaline phosphatase, which is an early marker for odontoblast differentiation, was also demonstrated. At 6 weeks after implantation the subcutaneous formation of radio-opaque calcified bodies was observed in situ. Immunohistochemical and fine structure studies identified expression of type I collagen, type III collagen, and DSP in the mineralizing transplants. Isolated odontoblast-like cells initiated dentin-like hard tissue formation and scattered autolyzing apoptotic cells were also observed in the transplants. The study showed that subcultured dental pulp cells actively differentiate into odontoblast-like cells and induce calcification in an alginate scaffold.

  1. Design and implementation of therapeutic ultrasound generating circuit for dental tissue formation and tooth-root healing.

    Science.gov (United States)

    Woon Tiong Ang; Scurtescu, C; Wing Hoy; El-Bialy, T; Ying Yin Tsui; Jie Chen

    2010-02-01

    Biological tissue healing has recently attracted a great deal of research interest in various medical fields. Trauma to teeth, deep and root caries, and orthodontic treatment can all lead to various degrees of root resorption. In our previous study, we showed that low-intensity pulsed ultrasound (LIPUS) enhances the growth of lower incisor apices and accelerates their rate of eruption in rabbits by inducing dental tissue growth. We also performed clinical studies and demonstrated that LIPUS facilitates the healing of orthodontically induced teeth-root resorption in humans. However, the available LIPUS devices are too large to be used comfortably inside the mouth. In this paper, the design and implementation of a low-power LIPUS generator is presented. The generator is the core of the final intraoral device for preventing tooth root loss and enhancing tooth root tissue healing. The generator consists of a power-supply subsystem, an ultrasonic transducer, an impedance-matching circuit, and an integrated circuit composed of a digital controller circuitry and the associated driver circuit. Most of our efforts focus on the design of the impedance-matching circuit and the integrated system-on-chip circuit. The chip was designed and fabricated using 0.8- ¿m high-voltage technology from Dalsa Semiconductor, Inc. The power supply subsystem and its impedance-matching network are implemented using discrete components. The LIPUS generator was tested and verified to function as designed and is capable of producing ultrasound power up to 100 mW in the vicinity of the transducer's resonance frequency at 1.5 MHz. The power efficiency of the circuitry, excluding the power supply subsystem, is estimated at 70%. The final products will be tailored to the exact size of teeth or biological tissue, which is needed to be used for stimulating dental tissue (dentine and cementum) healing.

  2. Environmental lead pollution and its possible influence on tooth loss and hard dental tissue lesions.

    Science.gov (United States)

    Cenić-Milosević, Desanka; Mileusnić, Ivan; Kolak, Veljko; Pejanović, Djordje; Ristić, Tamara; Jakovljević, Ankica; Popović, Milica; Pesić, Dragana; Melih, Irena

    2013-08-01

    Environmental lead (Pb) pollution is a global problem. Hard dental tissue is capable of accumulating lead and other hard metals from the environment. The aim of this study was to investigate any correlation between the concentration of lead in teeth extracted from inhabitants of Pancevo and Belgrade, Serbia, belonging to different age groups and occurrence of tooth loss, caries and non-carious lesions. A total of 160 volunteers were chosen consecutively from Pancevo (the experimental group) and Belgrade (the control group) and divided into 5 age subgroups of 32 subjects each. Clinical examination consisted of caries and hard dental tissue diagnostics. The Decayed Missing Filled Teeth (DMFT) Index and Significant Caries Index were calculated. Extracted teeth were freed of any organic residue by UV digestion and subjected to voltammetric analysis for the content of lead. The average DMFT scores in Pancevo (20.41) were higher than in Belgrade (16.52); in the patients aged 31-40 and 41-50 years the difference was significant (p lead concentration and the number of extracted teeth, number of carious lesions and non-carious lesions found in the patients living in Pancevo, one possible cause of tooth loss and hard dental tissue damage could be a long-term environmental exposure to lead.

  3. Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser

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    Beloica Miloš

    2014-01-01

    Full Text Available Goal of contemporary dentistry is to decrease the patient’s discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniques has led us to contemporary carbide tungsten and diamond borers that are used with obligatory water cooling. The innovation within this field represents newly developed polymer borers that can detect the difference between carious lesions and healthy tooth structure. In this way the cavity preparation may be performed without damaging dental healthy tissue. This is possible owing to their hardness which is lower than the hardness of intact dentin. Polymer borer preparation is painless with less vibration, while the increase in temperature is negligible. Lasers have been used in clinical dentistry since 1980s so it can be said that they represent a new technology. The function of lasers is based on ablation which requires water. Erbium lasers have shown the highest potential with their ability to produce effective ablation of hard dental tissues. Laser application in dentistry requires special training as well as some protective measures. Laser advantages, compared to traditional preparation techniques, involve the absence of vibration, painless preparation, possibility of preparation without anesthetic and easier patient’s adjustment to dental intervention which is of importance, especially in pediatric dentistry. [Projekat Ministarstva nauke Republike Srbije, br. 46009

  4. Viscoelastic Properties of Human Tracheal Tissues.

    Science.gov (United States)

    Safshekan, Farzaneh; Tafazzoli-Shadpour, Mohammad; Abdouss, Majid; Shadmehr, Mohammad B

    2017-01-01

    The physiological performance of trachea is highly dependent on its mechanical behavior, and therefore, the mechanical properties of its components. Mechanical characterization of trachea is key to succeed in new treatments such as tissue engineering, which requires the utilization of scaffolds which are mechanically compatible with the native human trachea. In this study, after isolating human trachea samples from brain-dead cases and proper storage, we assessed the viscoelastic properties of tracheal cartilage, smooth muscle, and connective tissue based on stress relaxation tests (at 5% and 10% strains for cartilage and 20%, 30%, and 40% for smooth muscle and connective tissue). After investigation of viscoelastic linearity, constitutive models including Prony series for linear viscoelasticity and quasi-linear viscoelastic, modified superposition, and Schapery models for nonlinear viscoelasticity were fitted to the experimental data to find the best model for each tissue. We also investigated the effect of age on the viscoelastic behavior of tracheal tissues. Based on the results, all three tissues exhibited a (nonsignificant) decrease in relaxation rate with increasing the strain, indicating viscoelastic nonlinearity which was most evident for cartilage and with the least effect for connective tissue. The three-term Prony model was selected for describing the linear viscoelasticity. Among different models, the modified superposition model was best able to capture the relaxation behavior of the three tracheal components. We observed a general (but not significant) stiffening of tracheal cartilage and connective tissue with aging. No change in the stress relaxation percentage with aging was observed. The results of this study may be useful in the design and fabrication of tracheal tissue engineering scaffolds.

  5. Effects of gamma radiation on hard dental tissues of albino rats using scanning electron microscope - Part 1

    Science.gov (United States)

    El-Faramawy, Nabil; Ameen, Reham; El-Haddad, Khaled; Maghraby, Ahmed; El-Zainy, Medhat

    2011-12-01

    In the present study, 40 adult male albino rats were used to study the effect of gamma radiation on the hard dental tissues (enamel surface, dentinal tubules and the cementum surface). The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy gamma doses. The effects of irradiated hard dental tissues samples were investigated using a scanning electron microscope. For doses up to 0.5 Gy, there was no evidence of the existence of cracks on the enamel surface. With 1 Gy irradiation dose, cracks were clearly observed with localized erosive areas. At 2 Gy irradiation dose, the enamel showed morphological alterations as disturbed prismatic and interprismatic areas. An increase in dentinal tubules diameter and a contemporary inter-tubular dentine volume decrease were observed with higher irradiation dose. Concerning cementum, low doses,<0.5 Gy, showed surface irregularities and with increase in the irradiation dose to≥1 Gy, noticeable surface irregularities and erosive areas with decrease in Sharpey's fiber sites were observed. These observations could shed light on the hazardous effects of irradiation fields to the functioning of the human teeth.

  6. Knowledge Assessment of the Dental Community in Texas on the Role of Human Papilloma Virus in Oropharyngeal Cancer.

    Science.gov (United States)

    Rowan, Stephanie D; Hu, Shirley L; Brotzman, Jacob S; Redding, Spencer W; Rankin, K Vendrell; Vigneswaran, Nadarajah

    2015-08-01

    The epidemiology of oral cancer is changing. From 1988 to 2004, there has been a dramatic increase in Human Papilloma virus (HPV) positive oropharyngeal squamous cell carcinoma (OPC) in the U.S. At the same time there have been decreasing rates of OPC associated with the traditional risk factors of smoking and alcohol consumption. The epidemiology of oral cancer is changing. As the epidemiology changes, it is important that the dental community recognize these factors. The goal of this study was to assess the baseline level of knowledge about HPV and OPC within the Texas dental community. Practicing dentists and dental hygienists from Texas dental professional networks and dental students from the three Texas schools of dentistry were recruited to participate in the study. Participants were requested to access and complete a 7-item online survey. To ensure anonymity, a third party practice facilitator or department administrator disseminated the survey link to participants. Of the 457 surveys completed, 100% of respondents reported conducting oral soft tissue examinations at least annually. However, only 73% included the oropharynx in their exam. Less than 50% of dental professionals selected the correct location of the greatest increase in oral cancer incidence during the last 10 years. Less than 30% of each of the groups answered correctly in indicating the age group with the most rapidly increasing incidence of oral cancer. Approximately 40% of all groups indicated that a biopsy from the posterior oropharynx should be tested for HPV. Survey results across Texas dentists, dental hygienists, and Texas dental students demonstrated a lack of knowledge of the changing profile of oral cancer regarding HPV-associated OPC. This aim of this initial phase was to determine the baseline level of knowledge surrounding the risks associated with oropharyngeal cancer in the survey population. Our goal is to utilize these findings to develop educational interventions that will

  7. Ultrashort pulse laser processing of hard tissue, dental restoration materials, and biocompatibles

    Science.gov (United States)

    Yousif, A.; Strassl, M.; Beer, F.; Verhagen, L.; Wittschier, M.; Wintner, E.

    2007-07-01

    During the last few years, ultra-short laser pulses have proven their potential for application in medical tissue treatment in many ways. In hard tissue ablation, their aptitude for material ablation with negligible collateral damage provides many advantages. Especially teeth representing an anatomically and physiologically very special region with less blood circulation and lower healing rates than other tissues require most careful treatment. Hence, overheating of the pulp and induction of microcracks are some of the most problematic issues in dental preparation. Up till now it was shown by many authors that the application of picosecond or femtosecond pulses allows to perform ablation with very low damaging potential also fitting to the physiological requirements indicated. Beside the short interaction time with the irradiated matter, scanning of the ultra-short pulse trains turned out to be crucial for ablating cavities of the required quality. One main reason for this can be seen in the fact that during scanning the time period between two subsequent pulses incident on the same spot is so much extended that no heat accumulation effects occur and each pulse can be treated as a first one with respect to its local impact. Extension of this advantageous technique to biocompatible materials, i.e. in this case dental restoration materials and titanium plasma-sprayed implants, is just a matter of consequence. Recently published results on composites fit well with earlier data on dental hard tissue. In case of plaque which has to be removed from implants, it turns out that removal of at least the calcified version is harder than tissue removal. Therefore, besides ultra-short lasers, also Diode and Neodymium lasers, in cw and pulsed modes, have been studied with respect to plaque removal and sterilization. The temperature increase during laser exposure has been experimentally evaluated in parallel.

  8. Human serum promotes osteogenic differentiation of human dental pulp stem cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Alessandra Pisciotta

    Full Text Available Human dental pulp is a promising alternative source of stem cells for cell-based tissue engineering in regenerative medicine, for the easily recruitment with low invasivity for the patient and for the self-renewal and differentiation potential of cells. So far, in vitro culture of mesenchymal stem cells is usually based on supplementing culture and differentiation media with foetal calf serum (FCS. FCS is known to contain a great quantity of growth factors, and thus to promote cell attachment on plastic surface as well as expansion and differentiation. Nevertheless, FCS as an animal origin supplement may represent a potential means for disease transmission besides leading to a xenogenic immune response. Therefore, a significant interest is focused on investigating alternative supplements, in order to obtain a sufficient cell number for clinical application, avoiding the inconvenients of FCS use. In our study we have demonstrated that human serum (HS is a suitable alternative to FCS, indeed its addition to culture medium induces a high hDPSCs proliferation rate and improves the in vitro osteogenic differentiation. Furthermore, hDPSCs-collagen constructs, pre-differentiated with HS-medium in vitro for 10 days, when implanted in immunocompromised rats, are able to restore critical size parietal bone defects. Therefore these data indicate that HS is a valid substitute for FCS to culture and differentiate in vitro hDPSCs in order to obtain a successful bone regeneration in vivo.

  9. Autoradiographic study of 3H-proline incorporation by rat periodontal ligament, gingival connective tissue and dental pulp

    International Nuclear Information System (INIS)

    Kameyama, Y.

    1975-01-01

    The rates of 3 H-proline incorporation by the rat periodontal ligament, the gingival connective tissue and the dental pulp were studied by autoradiography. The rate of 3 H-proline incorporation by the periodontal ligament was 2.8 times higher than by the gingival connective tissue and 5 times higher than by the dental pulp. These differences were significant (p 3 H-proline incorporation by the periodontal ligament was significantly different (p 3 H-proline incorporation. The ratio of the rates of 3 H-proline incorporation by the three tissues did not correlate with the ratio of the cellular densities in the same three tissues. (author)

  10. Direct evidence of milk consumption from ancient human dental calculus.

    Science.gov (United States)

    Warinner, C; Hendy, J; Speller, C; Cappellini, E; Fischer, R; Trachsel, C; Arneborg, J; Lynnerup, N; Craig, O E; Swallow, D M; Fotakis, A; Christensen, R J; Olsen, J V; Liebert, A; Montalva, N; Fiddyment, S; Charlton, S; Mackie, M; Canci, A; Bouwman, A; Rühli, F; Gilbert, M T P; Collins, M J

    2014-11-27

    Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15(th) century CE.

  11. The application of lesion sterilization and tissue repair 3Mix-MP for treating rat's dental pulp tissue

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    Raditya Nugroho

    2015-03-01

    Full Text Available Background: Lesion sterilization and tissue repair (LSTR 3Mix-MP are three broad-spectrum antibiotics, including metronidazole, ciprofloxacin and minocycline are mixed with propylene glycol or macrogol. There is the possibility ofthe healing process that marked proliferation ofnew blood vessels and proliferation offibroblasts in the treatment ofirreversible pulpitis by pulp capping LSTR 3MixMP because of  the principle of the method LSTR 3Mix-MP is to kill bacteria. Purpose: The purpose of this study to prove the effect of LSTR 3Mix-MP on chronic inflammation and the healing process in rat dental pulp tissue in vivo. Methods: Rattus norvegicus anaesthetized by using ketamine and xylazine dissolved in sterile isotonic saline solution (0.2 ml/50gr mm on the upper right thigh. Cavity preparation class I to perforation by using a low speed tapered diamond round bur. In the treatment group, rats were treated 3Mix-MP at a dose of10 mg and then covered with glass ionomer cement for 7 days on the pulp that has been opened for 3 days. The control group treated with saline irrigation on the pulp that has been opened for 3 days. Rats were killed after seven days, and then made preparations pulp tissue to count the number oflymphocytes, macrophages, plasma cells, blood vessels, and fibroblasts Results: There is an increase in the average number ofmacrophage cells, plasma, and fibroblasts; and decreased lymphocytes and blood vessels in the treated group exposure LSTR 3Mix-MP. Conclusion:LSTR 3Mix-MP can reduce chronic inflammation process and enhance the healing process in rat dental pulp tissue.

  12. Numerical Analysis of Masticatory Forces on a Lower First Molar considering the Contact between Dental Tissues

    Directory of Open Access Journals (Sweden)

    Rosa Alicia Hernández-Vázquez

    2018-01-01

    Full Text Available The aim of the present work is to identify the reactions of the dental organs to the different forces that occur during chewing and the transcendence of the union and contact maintained by the dental tissues. The study used a lower first molar biomodel with a real morphology and morphometry and consisting of the three dental tissues (enamel, dentin, and pulp each with its mechanical properties. In it, two simulations were carried out, as would the process of chewing a food. One of the simulations considers the contact between the enamel and the dentin, and the other does not take it into account. The results obtained differ significantly between the simulations that consider contact and those that do not, establishing the importance of taking this contact into account. In this way, the theories that establish horizontal and lateral occlusion forces are present during the functional chewing process which are viable to be correct. The case studies carried out present not only the reasons for the failure of enamel but also the failure of the restoration materials used. This reflection will allow the development of more adequate materials, mechanical design of prostheses, implants, and treatment.

  13. Dental Pulp Stem Cells as a multifaceted tool for bioengineering and the regeneration of craniomaxillofacial tissues

    Directory of Open Access Journals (Sweden)

    Maitane eAurrekoetxea

    2015-10-01

    Full Text Available Dental pulp stem cells, or DPSC, are neural crest-derived cells with an outstanding capacity to differentiate along multiple cell lineages of interest for cell therapy. In particular, highly efficient osteo/dentinogenic differentiation of DPSC can be achieved using simple in vitro protocols, making these cells a very attractive and promising tool for the future treatment of dental and periodontal diseases. Among craniomaxillofacial organs, the tooth and salivary gland are two such cases in which complete regeneration by tissue engineering using DPSC appears to be possible, as research over the last decade has made substantial progress in experimental models of partial or total regeneration of both organs, by cell recombination technology. Moreover, DPSC seem to be a particularly good choice for the regeneration of nerve tissues, including injured or transected cranial nerves. In this context, the oral cavity appears to be an excellent testing ground for new regenerative therapies using DPSC. However, many issues and challenges need yet to be addressed before these cells can be employed in clinical therapy. In this review, we point out some important aspects on the biology of DPSC with regard to their use for the reconstruction of different craniomaxillofacial tissues and organs, with special emphasis on cranial bones, nerves, teeth, and salivary glands. We suggest new ideas and strategies to fully exploit the capacities of DPSC for bioengineering of the aforementioned tissues.

  14. Use of radioisotopes in the study of permeability of hard dental tissue

    International Nuclear Information System (INIS)

    Tarjan, I.

    1978-01-01

    A literature survey. According to in vivo experiments 32 P, 131 I and 45 Ca penetrate dental enamel and dentine. In vitro studies revealed that the healthy enamel and that damaged by caries and dentine are penetrable by 22 Na and 24 Na both in centripetal and in centrifugal directions. 32 P, 18 F and urea, labelled with 14 C penetrate healthy hard dental tissue. 45 CaCl 2 , 110 AgNO 3 , 111 AgNO 3 , 103 PdCl 2 , 64 Cu(NO 3 ) 2 , 63 ZnCl 2 , 65 ZnCl 2 and glucose, labelled with 14 C penetrate enamel defects, lamellas and caries areas. 239 Pu citrate complex links to the surface of enamel and cement, but does not penetrate them. (author)

  15. Use of radioisotopes in the study of permeability of hard dental tissue

    Energy Technology Data Exchange (ETDEWEB)

    Tarjan, I [Semmelweis Orvostudomanyi Egyetem, Budapest (Hungary)

    1978-04-01

    A literature survey. According to in vivo experiments /sup 32/P, /sup 131/I and /sup 45/Ca penetrate dental enamel and dentine. In vitro studies revealed that the healthy enamel and that damaged by caries and dentine are penetrable by /sup 22/Na and /sup 24/Na both in centripetal and in centrifugal directions. /sup 32/P, /sup 18/F and urea, labelled with /sup 14/C penetrate healthy hard dental tissue. /sup 45/CaCl/sub 2/, /sup 110/AgNO/sub 3/, /sup 111/AgNO/sub 3/, /sup 103/PdCl/sub 2/, /sup 64/Cu(NO/sub 3/)/sub 2/, /sup 63/ZnCl/sub 2/, /sup 65/ZnCl/sub 2/ and glucose, labelled with /sup 14/C penetrate enamel defects, lamellas and caries areas. /sup 239/Pu citrate complex links to the surface of enamel and cement, but does not penetrate them.

  16. Beta adrenergic receptors in human cavernous tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.

    1985-04-01

    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  17. Soft tissue adhesion of polished versus glazed lithium disilicate ceramic for dental applications.

    Science.gov (United States)

    Brunot-Gohin, C; Duval, J-L; Azogui, E-E; Jannetta, R; Pezron, I; Laurent-Maquin, D; Gangloff, S C; Egles, C

    2013-09-01

    Ceramics are widely used materials for prosthesis, especially in dental fields. Despite multiple biomedical applications, little is known about ceramic surface modifications and the resulting cell behavior at its contact. The aim of this study is to evaluate the biological response of polished versus glazed surface treatments on lithium disilicate dental ceramic. We studied a lithium disilicate ceramic (IPS e.max(®) Press, Ivoclar Vivadent) with 3 different surface treatments: raw surface treatment, hand polished surface treatment, and glazed surface treatment (control samples are Thermanox(®), Nunc). In order to evaluate the possible modulation of cell response at the surface of ceramic, we compared polished versus glazed ceramics using an organotypic culture model of chicken epithelium. Our results show that the surface roughness is not modified as demonstrated by equivalent Ra measurements. On the contrary, the contact angle θ in water is very different between polished (84°) and glazed (33°) samples. The culture of epithelial tissues allowed a very precise assessment of histocompatibility of these interfaces and showed that polished samples increased cell adhesion and proliferation as compared to glazed samples. Lithium disilicate polished ceramic provided better adhesion and proliferation than lithium disilicate glazed ceramic. Taken together, our results demonstrate for the first time, how it is possible to use simple surface modifications to finely modulate the adhesion of tissues. Our results will help dental surgeons to choose the most appropriate surface treatment for a specific clinical application, in particular for the ceramic implant collar. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  18. WNT5A inhibits human dental papilla cell proliferation and migration

    International Nuclear Information System (INIS)

    Peng, L.; Ye, L.; Dong, G.; Ren, L.B.; Wang, C.L.; Xu, P.; Zhou, X.D.

    2009-01-01

    WNT proteins are a large family of cysteine-rich secreted molecules that are linked to both canonical and non-canonical signal pathways, and have been implicated in oncogenesis and tissue development. Canonical WNT proteins have been proven to play critical roles in tooth development, while little is known about the role of non-canonical WNT proteins such as WNT5A. In this study, WNT5A was localized to human dental papilla tissue and human dental papilla cells (HDPCs) cultured in vitro, using immunochemistry and RT-PCR. Recombinant adenovirus encoding full-length Wnt5a cDNA was constructed to investigate the biological role of WNT5A on HDPCs. The BrdU incorporation assay, the MTT assay and flow cytometric analysis showed that over-expression of Wnt5a strongly inhibited the proliferation of HDPCs in vitro. Wound healing and transwell migration assays indicated that over-expression of WNT5A reduced migration of HDPCs. In conclusion, our results showed that WNT5A negatively regulates both proliferation and migration of HDPCs, suggesting its important role in odontogenesis via controlling the HDPCs.

  19. Cytotoxic effects of glass ionomer cements on human dental pulp stem cells correlate with fluoride release.

    Science.gov (United States)

    Kanjevac, Tatjana; Milovanovic, Marija; Volarevic, Vladislav; Lukic, Miodrag L; Arsenijevic, Nebojsa; Markovic, Dejan; Zdravkovic, Nebojsa; Tesic, Zivoslav; Lukic, Aleksandra

    2012-01-01

    Glass ionomer cements (GICs) are commonly used as restorative materials. Responses to GICs differ among cell types and it is therefore of importance to thoroughly investigate the influence of these restorative materials on pulp stem cells that are potential source for dental tissue regeneration. Eight biomaterials were tested: Fuji I, Fuji II, Fuji VIII, Fuji IX, Fuji Plus, Fuji Triage, Vitrebond and Composit. We compared their cytotoxic activity on human dental pulp stem cells (DPSC) and correlated this activity with the content of Fluoride, Aluminium and Strontium ions in their eluates. Elution samples of biomaterials were prepared in sterile tissue culture medium and the medium was tested for toxicity by an assay of cell survival/proliferation (MTT test) and apoptosis (Annexin V FITC Detection Kit). Concentrations of Fluoride, Aluminium and Strontium ions were tested by appropriate methods in the same eluates. Cell survival ranged between 79.62% (Fuji Triage) to 1.5% (Fuji Plus) and most dead DPSCs were in the stage of late apoptosis. Fluoride release correlated with cytotoxicity of GICs, while Aluminium and Strontium ions, present in significant amount in eluates of tested GICs did not. Fuji Plus, Vitrebond and Fuji VIII, which released fluoride in higher quantities than other GICs, were highly toxic to human DPSCs. Opposite, low levels of released fluoride correlated to low cytotoxic effect of Composit, Fuji I and Fuji Triage.

  20. Staining plastic blocks with triiodide to image cells and soft tissues in backscattered electron SEM of skeletal and dental tissues

    Directory of Open Access Journals (Sweden)

    A Boyde

    2012-07-01

    Full Text Available Backscattered electron scanning electron microscopy (BSE SEM is an invaluable method for studying the histology of the hard, mineralised components of poly-methyl methacrylate (PMMA or other resin embedded skeletal and dental tissues. Intact tissues are studied in micro-milled or polished block faces with an electron-optical section thickness of the order of a half to one micron and with the area of the section as big as a whole – large or small – bone organ. However, BSE SEM does not give information concerning the distribution of uncalcified, ‘soft’, cellular and extracellular matrix components. This can be obtained by confocal microscopy of the same block and the two sorts of images merged but the blocks have to be studied in two microscope systems. The present work shows a new, simple and economic approach to visualising both components by using the triiodide ion in Lugol's iodine solution to stain the block surface prior to the application of any conductive coating – and the latter can be omitted if charging is suppressed by use of poor vacuum conditions in the SEM sample chamber. The method permits the use of archival tissue, and it will be valuable in studies of both normal growth and development and pathological changes in bones and joints, including osteoporosis and osteoarthritis, and tissue adaptation to implants.

  1. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells

    OpenAIRE

    Soichiro Sonoda; Haruyoshi Yamaza; Lan Ma; Yosuke Tanaka; Erika Tomoda; Reona Aijima; Kazuaki Nonaka; Toshio Kukita; Songtao Shi; Fusanori Nishimura; Takayoshi Yamaza

    2016-01-01

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we...

  2. Sensory Neuropeptides and Endogenous Opioids Expression in Human Dental Pulp with Asymptomatic Inflammation: In Vivo Study

    Directory of Open Access Journals (Sweden)

    Daniel Chavarria-Bolaños

    2015-01-01

    Full Text Available Purpose. This study quantified the expression of substance P (SP, calcitonin gene-related peptide (CGRP, β-endorphins (β-End, and methionine-enkephalin (Met-Enk in human dental pulp following orthodontic intrusion. Methods. Eight patients were selected according to preestablished inclusion criteria. From each patient, two premolars (indicated for extraction due to orthodontic reasons were randomly assigned to two different groups: the asymptomatic inflammation group (EXPg, which would undergo controlled intrusive force for seven days, and the control group (CTRg, which was used to determine the basal levels of each substance. Once extracted, dental pulp tissue was prepared to determine the expression levels of both neuropeptides and endogenous opioids by radioimmunoassay (RIA. Results. All samples from the CTRg exhibited basal levels of both neuropeptides and endogenous opioids. By day seven, all patients were asymptomatic, even when all orthodontic-intrusive devices were still active. In the EXPg, the SP and CGRP exhibited statistically significant different levels. Although none of the endogenous opioids showed statistically significant differences, they all expressed increasing trends in the EXPg. Conclusions. SP and CGRP were identified in dental pulp after seven days of controlled orthodontic intrusion movement, even in the absence of pain.

  3. Wear measurement of dental tissues and materials in clinical studies: A systematic review.

    Science.gov (United States)

    Wulfman, C; Koenig, V; Mainjot, A K

    2018-06-01

    This study aims to systematically review the different methods used for wear measurement of dental tissues and materials in clinical studies, their relevance and reliability in terms of accuracy and precision, and the performance of the different steps of the workflow taken independently. An exhaustive search of clinical studies related to wear of dental tissues and materials reporting a quantitative measurement method was conducted. MedLine, Embase, Scopus, Cochrane Library and Web of Science databases were used. Prospective studies, pilot studies and case series (>10 patients), as long as they contained a description of wear measurement methodology. Only studies published after 1995 were considered. After duplicates' removal, 495 studies were identified, and 41 remained for quantitative analysis. Thirty-four described wear-measurement protocols, using digital profilometry and superimposition, whereas 7 used alternative protocols. A specific form was designed to analyze the risk of bias. The methods were described in terms of material analyzed; study design; device used for surface acquisition; matching software details and settings; type of analysis (vertical height-loss measurement vs volume loss measurement); type of area investigated (entire occlusal area or selective areas); and results. There is a need of standardization of clinical wear measurement. Current methods exhibit accuracy, which is not sufficient to monitor wear of restorative materials and tooth tissues. Their performance could be improved, notably limiting the use of replicas, using standardized calibration procedures and positive controls, optimizing the settings of scanners and matching softwares, and taking into account unusable data. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

  4. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    Directory of Open Access Journals (Sweden)

    Stamatović Novak

    2013-01-01

    Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

  5. Prevalence of developmental dental hard-tissue anomalies and association with caries and oral hygiene status of children in Southwestern, Nigeria.

    Science.gov (United States)

    Popoola, Bamidele O; Onyejaka, Nneka; Folayan, Morenike O

    2016-07-07

    Developmental dental hard tissue anomalies are often associated with oral health problems. This study determined the clinical prevalence of developmental dental hard tissue anomalies in the permanent dentition of children resident in southwestern Nigeria and its association with dental caries and poor oral hygiene status. This was a cross-sectional study recruiting 1565 school children, 12 to 15 year old attending schools in Ibadan, Oyo State and Ile-Ife, Osun State. All eligible study participants had oral examinations conducted to determine presence of developmental hard dental tissue anomalies, caries and oral hygiene status. The prevalence of developmental dental hard tissue anomalies was determined. Logistic Poisson regression was used to determine the association of between developmental dental hard tissue anomalies, caries and oral hygiene status. Only 65 (4.2 %) children had clinically diagnosed developmental dental hard tissue anomalies. The most prevalent anomaly was enamel hypoplasia (2.2 %). More females (p = 0.003) and more children with middle socioeconomic class (p = 0.001) had enamel hypoplasia. The probability of having poor oral hygiene was significantly increased for children with developmental dental anomalies (APR: 0.07; 95 % CI: 0.03 - 0.12; p = 0.002). The probability of having caries was insignificantly increased for children with developmental dental hard tissue anomalies (APR: 0.005; 95 % CI: -0.03 - 0.04; p = 0.08). The most prevalence clinically detectable developmental dental hard tissue anomalies for the study population was enamel hypoplasia. The presence of developmental dental hard tissue anomalies significantly increased the chances of having poor oral hygiene but not caries. Further studies are required to understand if poor oral hygiene is associated with dental caries in children with developmental dental hard tissue anomalies.

  6. Optical measurement of acidification of human dental plaque in vitro

    Science.gov (United States)

    Graham, Jasmine Y.; Nelson, Leonard Y.; Seibel, Eric J.

    2018-02-01

    A pH measurement of oral biofilms is helpful for monitoring the impact of acidogenic bacteria in the caries process. Demineralization of dental enamel is closely related to the time dependent pH of human plaque. Therefore, providing a means to easily measure the local pH of biofilms is a useful clinical diagnostic in the arsenal of caries prevention tools. Optical measurement methods of plaque metabolism can use intrinsic fluorescence or extrinsic fluorescence from added dyes. Autofluorescence spectral features of human oral biofilms at green (500 nm) and red (634 nm) fluorescence wavelengths using 405 nm excitation did not demonstrate a spectral or intensity shift between neutral and acidic conditions. Chlorin e6, an ingredient in chlorophyllin food supplement, exhibited a spectral and intensity shift of fluorescence emission in buffered solutions, but this quantitative pH-dependence was not transferable to a human plaque environment. Finally, a ratiometric quantitative pH measure was achieved by exciting (405 nm laser) a mixture of two dyes, fluorescein and rhodamine B. This two-dye mixture produced two strong fluorescent bands centered at 515 nm (fluorescein) and 580 nm (rhodamine B), where the 515 nm band was pH sensitive and the 580 nm band served as a pH insensitive reference. This dual-dye fluorescence ratio exhibited a linear response over pH 7 to 5 in human oral biofilms during a sugar challenge. We have explored methods to use non-contact, optical measures of local acidity levels in difficult to access dental locations such as occlusal fissures using various pH sensitive fluorescent dye systems.

  7. Exogenous mineralization of hard tissues using photo-absorptive minerals and femto-second lasers; the case of dental enamel.

    Science.gov (United States)

    Anastasiou, A D; Strafford, S; Thomson, C L; Gardy, J; Edwards, T J; Malinowski, M; Hussain, S A; Metzger, N K; Hassanpour, A; Brown, C T A; Brown, A P; Duggal, M S; Jha, A

    2018-04-15

    A radical new methodology for the exogenous mineralization of hard tissues is demonstrated in the context of laser-biomaterials interaction. The proposed approach is based on the use of femtosecond pulsed lasers (fs) and Fe 3+ -doped calcium phosphate minerals (specifically in this work fluorapatite powder containing Fe 2 O 3 nanoparticles (NP)). A layer of the synthetic powder is applied to the surface of eroded bovine enamel and is irradiated with a fs laser (1040 nm wavelength, 1 GHz repetition rate, 150 fs pulse duration and 0.4 W average power). The Fe 2 O 3 NPs absorb the light and may act as thermal antennae, dissipating energy to the vicinal mineral phase. Such a photothermal process triggers the sintering and densification of the surrounding calcium phosphate crystals thereby forming a new, dense layer of typically ∼20 μm in thickness, which is bonded to the underlying surface of the natural enamel. The dispersed iron oxide NPs, ensure the localization of temperature excursion, minimizing collateral thermal damage to the surrounding natural tissue during laser irradiation. Simulated brushing trials (pH cycle and mechanical force) on the synthetic layer show that the sintered material is more acid resistant than the natural mineral of enamel. Furthermore, nano-indentation confirms that the hardness and Young's modulus of the new layers are significantly more closely matched to enamel than current restorative materials used in clinical dentistry. Although the results presented herein are exemplified in the context of bovine enamel restoration, the methodology may be more widely applicable to human enamel and other hard-tissue regenerative engineering. In this work we provide a new methodology for the mineralisation of dental hard tissues using femtosecond lasers and iron doped biomaterials. In particular, we demonstrate selective laser sintering of an iron doped fluorapatite on the surface of eroded enamel under low average power and mid

  8. UWB pulse propagation into human tissues

    International Nuclear Information System (INIS)

    Cavagnaro, Marta; Pittella, Erika; Pisa, Stefano

    2013-01-01

    In this paper the propagation of a UWB pulse into a layered model of the human body is studied to characterize absorption and reflection of the UWB signal due to the different body tissues. Several time behaviours for the incident UWB pulse are considered and compared with reference to the feasibility of breath and heartbeat activity monitoring. Results show that if the UWB source is placed far from the human body, the reflection coming from the interface between air and skin can be used to detect the respiratory activity. On the contrary, if the UWB source is placed close to the human body, a small reflection due to the interface between the posterior lung wall and the bone, which is well distanced in time from the reflections due to the first layers of the body model, can be used to detect lung and heart changes associated with the cardio-respiratory activity. (paper)

  9. CD146 positive human dental pulp stem cells promote regeneration of dentin/pulp-like structures.

    Science.gov (United States)

    Matsui, Mikiko; Kobayashi, Tomoko; Tsutsui, Takeo W

    2018-04-01

    CD146 and STRO-1 are endothelial biomarkers that are co-expressed on the cellular membranes of blood vessels within human dental pulp tissue. This study characterized the percentage of dentin-like structures produced by CD146-positive (CD146 + ) human dental pulp stem cells (DPSCs), compared with their CD146-negative (CD146 - ) counterparts. DPSC populations were enriched using magnetic-activated cell sorting (MACS), yielding CD146 + and CD146 - cells, as well as mixtures composed of 25% CD146 + cells and 75% CD146 - cells (CD146 +/- ). Cell growth assays indicated that CD146 + cells exhibit an approximate 3-4 h difference in doubling time, compared with CD146 - cells. Cell cycle distributions were determined by flow cytometry analysis. The low percentage of CD146 + cells' DNA content in G 0 /G 1 phase were compared with CD146 - and non-separated cells. In contrast to CD146 - and non-separated cells, prompt mineralization was observed in CD146 + cells. Subsequently, qRT-PCR revealed high mRNA expression of CD146 and Alkaline phosphatase in mineralization-induced CD146 + cells. CD146 + cells were also observed high adipogenic ability by Oil red O staining. Histological examinations revealed an increased area of dentin/pulp-like structures in transplanted CD146 + cells, compared with CD146 - and CD146 +/- cells. Immunohistochemical studies detected dentin matrix protein-1 (DMP1) and dentin sialophosphoprotein (DSPP), as well as human mitochondria, in transplanted DPSCs. Co-expression of CD146 and GFP indicated that CD146 was expressed in transplanted CD146 + cells. CD146 + cells may promote mineralization and generate dentin/pulp-like structures, suggesting a role in self-renewal of stem cells and dental pulp regenerative therapy.

  10. Development of highly porous scaffolds based on bioactive silicates for dental tissue engineering

    International Nuclear Information System (INIS)

    Goudouri, O.M.; Theodosoglou, E.; Kontonasaki, E.; Will, J.; Chrissafis, K.; Koidis, P.; Paraskevopoulos, K.M.; Boccaccini, A.R.

    2014-01-01

    Graphical abstract: - Highlights: • Synthesis of an Mg-based glass-ceramic via the sol–gel technique. • The heat treatment of the glass-ceramic promoted the crystallization of akermanite. • Akermanite scaffolds coated with gelatin were successfully fabricated. • An HCAp layer was developed on the surface of all scaffolds after 9 days in SBF. - Abstract: Various scaffolding materials, ceramics and especially Mg-based ceramic materials, including akermanite (Ca 2 MgSi 2 O 7 ) and diopside (CaMgSi 2 O 6 ), have attracted interest for dental tissue regeneration because of their improved mechanical properties and controllable biodegradation. The aim of the present work was the synthesis of an Mg-based glass-ceramic, which would be used for the construction of workable akermanite scaffolds. The characterization of the synthesized material was performed by Fourier Transform Infrared Spectroscopy (FTIR) X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM). Finally, the apatite forming ability of the scaffolds was assessed by immersion in simulated body fluid. The scaffolds were fabricated by the foam replica technique and were subsequently coated with gelatin to provide a functional surface for increased cell attachment. Finally, SEM microphotographs and FTIR spectra of the scaffolds after immersion in SBF solution indicated the inorganic bioactive character of the scaffolds suitable for the intended applications in dental tissue engineering

  11. Development of highly porous scaffolds based on bioactive silicates for dental tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Goudouri, O.M., E-mail: menti.goudouri@ww.uni-erlangen.de [Institute for Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen (Germany); Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Theodosoglou, E. [School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kontonasaki, E. [Department of Fixed Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Will, J. [Institute for Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen (Germany); Chrissafis, K. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Koidis, P. [Department of Fixed Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Paraskevopoulos, K.M. [Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Boccaccini, A.R. [Institute for Biomaterials, University of Erlangen-Nuremberg, 91058 Erlangen (Germany)

    2014-01-01

    Graphical abstract: - Highlights: • Synthesis of an Mg-based glass-ceramic via the sol–gel technique. • The heat treatment of the glass-ceramic promoted the crystallization of akermanite. • Akermanite scaffolds coated with gelatin were successfully fabricated. • An HCAp layer was developed on the surface of all scaffolds after 9 days in SBF. - Abstract: Various scaffolding materials, ceramics and especially Mg-based ceramic materials, including akermanite (Ca{sub 2}MgSi{sub 2}O{sub 7}) and diopside (CaMgSi{sub 2}O{sub 6}), have attracted interest for dental tissue regeneration because of their improved mechanical properties and controllable biodegradation. The aim of the present work was the synthesis of an Mg-based glass-ceramic, which would be used for the construction of workable akermanite scaffolds. The characterization of the synthesized material was performed by Fourier Transform Infrared Spectroscopy (FTIR) X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM). Finally, the apatite forming ability of the scaffolds was assessed by immersion in simulated body fluid. The scaffolds were fabricated by the foam replica technique and were subsequently coated with gelatin to provide a functional surface for increased cell attachment. Finally, SEM microphotographs and FTIR spectra of the scaffolds after immersion in SBF solution indicated the inorganic bioactive character of the scaffolds suitable for the intended applications in dental tissue engineering.

  12. Effects of gamma radiation on hard dental tissues of albino rats: investigation by light microscopy.

    Science.gov (United States)

    El-Faramawy, Nabil; Ameen, Reham; El-Haddad, Khaled; El-Zainy, Medhat

    2013-08-01

    The present work aims at studying the effect of gamma radiation on the hard dental tissues. Eighty adult male albino rats with weights of about 250 g were used. The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy whole-body gamma doses. The effects on hard dental tissue samples were investigated after 48 h in histological and ground sections using light microscopy. Areas of acid phosphatase activity were detected using tartrate-resistant acid phosphatase (TRAP) stains. Observation of histological sections revealed disturbance in predentin thickness and odontoblastic layer as the irradiation dose increased. In cementum, widened cementocytes lacunae were occasionally detected even with low irradiated doses. On the other hand, relatively homogenous enamel was detected with darkened areas in enamel surface at doses over than 0.5 Gy. TRAP-positive cells were detected on the surface of the dentin of irradiated groups as well as cementum surface. Minimal detectable changes were observed in ground sections.

  13. The effect of dental bleaching on pulpal tissue response in a diabetic animal model.

    Science.gov (United States)

    Cintra, L T A; Ferreira, L L; Benetti, F; Gastélum, A A; Gomes-Filho, J E; Ervolino, E; Briso, A L F

    2017-08-01

    To evaluate pulpal tissue response after dental bleaching in normal and alloxan-induced diabetic rats. Twenty-eight rats were divided into two groups of normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with alloxan. After DM confirmation, all rats were anaesthetized and dental bleaching was performed with 35% hydrogen peroxide (H 2 O 2 ) on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 or 30 days, the animals were euthanized and the hemimaxillae were removed, processed for histopathological analysis and stained with haematoxylin-eosin (HE), Masson's trichrome (MT) and picrosirius red (PSR). Results obtained within animals (normoglycaemic or diabetic rats) were submitted to Wilcoxon or paired t-tests, and between animal (normoglycaemic and diabetic rats), to Mann-Whitney test or t-tests. At 2 days, the NBle group had a mild inflammatory infiltration in the pulpal tissue, whilst the DBle had severe inflammation or necrosis (P bleaching was greater in diabetic rats. Additionally, the increase in reactionary dentine deposition and mature collagen fibres observed in diabetic rats needs further evaluation to confirm the present results. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  14. Effect of different calcium phosphate scaffold ratios on odontogenic differentiation of human dental pulp cells

    Energy Technology Data Exchange (ETDEWEB)

    AbdulQader, Sarah Talib [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Department of Pedodontic and Preventive Dentistry, College of Dentistry, University of Baghdad, Baghdad (Iraq); Kannan, Thirumulu Ponnuraj, E-mail: kannan@usm.my [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Human Genome Centre, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Rahman, Ismail Ab [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia); Ismail, Hanafi [School of Materials and Minerals Resource Engineering, Universiti Sains Malaysia, 14300 Penang (Malaysia); Mahmood, Zuliani [School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2015-04-01

    Calcium phosphate (CaP) scaffolds have been widely and successfully used with osteoblast cells for bone tissue regeneration. However, it is necessary to investigate the effects of these scaffolds on odontoblast cells' proliferation and differentiation for dentin tissue regeneration. In this study, three different hydroxyapatite (HA) to beta tricalcium phosphate (β-TCP) ratios of biphasic calcium phosphate (BCP) scaffolds, BCP20, BCP50, and BCP80, with a mean pore size of 300 μm and 65% porosity were prepared from phosphoric acid (H{sub 2}PO{sub 4}) and calcium carbonate (CaCO{sub 3}) sintered at 1000 °C for 2 h. The extracts of these scaffolds were assessed with regard to cell viability and differentiation of odontoblasts. The high alkalinity, more calcium, and phosphate ions released that were exhibited by BCP20 decreased the viability of human dental pulp cells (HDPCs) as compared to BCP50 and BCP80. However, the cells cultured with BCP20 extract expressed high alkaline phosphatase activity and high expression level of bone sialoprotein (BSP), dental matrix protein-1 (DMP-1), and dentin sialophosphoprotein (DSPP) genes as compared to that cultured with BCP50 and BCP80 extracts. The results highlighted the effect of different scaffold ratios on the cell microenvironment and demonstrated that BCP20 scaffold can support HDPC differentiation for dentin tissue regeneration. - Highlights: • BCPs of different HA/β-TCP ratios influence cell microenvironment. • BCP20 decreases cell viability of HDPCs as compared to BCP50 and BCP80. • HDPCs cultured with BCP20 express highest ALP activity. • HDPCs cultured with BCP20 up-regulate BSP, DMP-1 and DSPP gene expressions. • BCP20 can support HDPC differentiation for dentin tissue regeneration.

  15. Effect of different calcium phosphate scaffold ratios on odontogenic differentiation of human dental pulp cells

    International Nuclear Information System (INIS)

    AbdulQader, Sarah Talib; Kannan, Thirumulu Ponnuraj; Rahman, Ismail Ab; Ismail, Hanafi; Mahmood, Zuliani

    2015-01-01

    Calcium phosphate (CaP) scaffolds have been widely and successfully used with osteoblast cells for bone tissue regeneration. However, it is necessary to investigate the effects of these scaffolds on odontoblast cells' proliferation and differentiation for dentin tissue regeneration. In this study, three different hydroxyapatite (HA) to beta tricalcium phosphate (β-TCP) ratios of biphasic calcium phosphate (BCP) scaffolds, BCP20, BCP50, and BCP80, with a mean pore size of 300 μm and 65% porosity were prepared from phosphoric acid (H 2 PO 4 ) and calcium carbonate (CaCO 3 ) sintered at 1000 °C for 2 h. The extracts of these scaffolds were assessed with regard to cell viability and differentiation of odontoblasts. The high alkalinity, more calcium, and phosphate ions released that were exhibited by BCP20 decreased the viability of human dental pulp cells (HDPCs) as compared to BCP50 and BCP80. However, the cells cultured with BCP20 extract expressed high alkaline phosphatase activity and high expression level of bone sialoprotein (BSP), dental matrix protein-1 (DMP-1), and dentin sialophosphoprotein (DSPP) genes as compared to that cultured with BCP50 and BCP80 extracts. The results highlighted the effect of different scaffold ratios on the cell microenvironment and demonstrated that BCP20 scaffold can support HDPC differentiation for dentin tissue regeneration. - Highlights: • BCPs of different HA/β-TCP ratios influence cell microenvironment. • BCP20 decreases cell viability of HDPCs as compared to BCP50 and BCP80. • HDPCs cultured with BCP20 express highest ALP activity. • HDPCs cultured with BCP20 up-regulate BSP, DMP-1 and DSPP gene expressions. • BCP20 can support HDPC differentiation for dentin tissue regeneration

  16. In Vitro Osteogenic and Odontogenic Differentiation of Human Dental Pulp Stem Cells Seeded on Carboxymethyl Cellulose-Hydroxyapatite Hybrid Hydrogel.

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    Gabriella eTeti

    2015-10-01

    Full Text Available Stem cells from human dental pulp have been considered as an alternative source of adult stem cells in tissue engineering because of their potential to differentiate into multiple cell lineages.Recently, polysaccharide based hydrogels have become especially attractive as matrices for the repair and regeneration of a wide variety of tissues and organs. The incorporation of inorganic minerals as hydroxyapatite nanoparticles can modulate the performance of the scaffolds with potential applications in tissue engineering. The aim of this study was to verify the osteogenic and odontogenic differentiation of dental pulp stem cells (DPSCs cultured on a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Human DPSCs were seeded on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel and on carboxymethyl cellulose hydrogel for 1, 3, 5, 7, 14 and 21 days. Cell viability assay and ultramorphological analysis were carried out to evaluate biocompatibility and cell adhesion. Real Time PCR was carried out to demonstrate the expression of osteogenic and odontogenic markers. Results showed a good adhesion and viability in cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel, while a low adhesion and viability was observed in cells cultured on carboxymethyl cellulose hydrogel. Real Time PCR data demonstrated a temporal up-regulation of osteogenic and odontogenic markers in dental pulp stem cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. In conclusion, our in vitro data confirms the ability of DPSCs to differentiate toward osteogenic and odontogenic lineages in presence of a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Taken together, our results provide evidence that DPSCs and carboxymethyl cellulose—hydroxyapatite hybrid hydrogel could be considered promising candidates for dental pulp complex and periodontal tissue engineering.

  17. Environmental lead pollution and its possible influence on tooth loss and hard dental tissue lesions

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    Cenić-Milošević Desanka

    2013-01-01

    Full Text Available Bacground/Aim. Environmental lead (Pb pollution is a global problem. Hard dental tissue is capable of accumulating lead and other hard metals from the environment. The aim of this study was to investigate any correlation between the concentration of lead in teeth extracted from inhabitants of Pančevo and Belgrade, Serbia, belonging to different age groups and occurrence of tooth loss, caries and non-carious lesions. Methods. A total of 160 volunteers were chosen consecutively from Pančevo (the experimental group and Belgrade (the control group and divided into 5 age subgroups of 32 subjects each. Clinical examination consisted of caries and hard dental tissue diagnostics. The Decayed Missing Filled Teeth (DMFT Index and Significant Caries Index were calculated. Extracted teeth were freed of any organic residue by UV digestion and subjected to voltammetric analysis for the content of lead. Results. The average DMFT scores in Pančevo (20.41 were higher than in Belgrade (16.52; in the patients aged 31-40 and 41-50 years the difference was significant (p < 0.05 and highly significant in the patients aged 51-60 (23.69 vs 18.5, p < 0.01. Non-carious lesions were diagnosed in 71 (44% patients from Pančevo and 39 (24% patients from Belgrade. The concentrations of Pb in extracted teeth in all the groups from Pančevo were statistically significantly (p < 0.05 higher than in all the groups from Belgrade. In the patients from Pančevo correlations between Pb concentration in extracted teeth and the number of extracted teeth, the number of carious lesions and the number of non-carious lesions showed a statistical significance (p < 0.001, p < 0.01 and p < 0.001, respectively. Conclusion. According to correlations between lead concentration and the number of extracted teeth, number of carious lesions and non-carious lesions found in the patients living in Pančevo, one possible cause of tooth loss and hard dental tissue damage could be a long

  18. Factors causing risks of caries evolvement in dental solid tissues under acclimatization

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    R.S. Rakhmanov

    2017-12-01

    Full Text Available We analyzed parameters characterizing mineral balance in a body and dental state in two groups of healthy men (n = 15 in each, aged 34.7 ± 0.6 in hot and humid marine climate conditions; one group was made of people undergoing acclimatization, the second one consisted of local population. We assessed working conditions and their category, and metrological data with determining environmental thermal load (ETL-index. Both groups worked outdoors; their labor had IIb category; they had to work overtime and under increased psy-choemotional loads; their working conditions differed as per nutrition and accommodation. When people from both groups had to work beyond their permanent location, their nutrition was represented by individual rations. Labor hardness was assessed as 3.2; labor intensity, as 3.2. Daytime temperature reached 30,0 С, relative air humidity was 77.3 ± 2.6 %, wind speed was 4.3 ± 0.3 m/sec. Microclimate was assessed as having 3.1 hazard category. Overall, working conditions were assessed as hazardous (3.3 hazard category. Electrolyte balance in a body was violated and it was proved by ower contents of K, Na, and Cl in blood serum; it was more apparent in people who were undergoing acclimatization. 70.0 % of local people had Ca contents in blood serum lower than the physiological standard. Lower Ca and increased P contents in blood serum were also detected in those undergoing acclimatization which could be evidence that Ca was washed out of a body and greater risk of dental caries occurred. As per observation dynamics we detected the following processes in people undergoing acclimatization: pH saliva and its mineralizing function shifting to acidity, salivation rate, and lower enamel resistance; they proved there was a growth in dental solid tissues demineralization. These parameters corresponded to those detected in local population. It calls for primary prevention activities aimed at fighting caries of dental solid tissues.

  19. Fractionation parameters for human tissues and tumors

    International Nuclear Information System (INIS)

    Thames, H.D.; Turesson, I.; Bogaert, W. van den

    1989-01-01

    Time-dose factors such as fractionation sensitivity (α/β) can sometimes be estimated from clinical data, when there is a wide variation in dose, fraction size, treatment time, etc. This report summarizes estimates of fractionation parameters derived from clinical results. Consistent with the animal data, α/β is higher for acutely responding than for late-responding normal tissues. While many human tumors seem to be characterized by high α/β values, there are exceptions (e.g. melanomas). Repair kinetics may be slower in human than in rodent skin and mucosa, but there are no hard and fast estimates of the repair halftime. Regeneration in head and neck tumors is equivalent to a daily dose of 1 Gy or less, while in the mucosa it is equivalent to approximately 1.8 Gy/day. (author)

  20. Vitrification and xenografting of human ovarian tissue.

    Science.gov (United States)

    Amorim, Christiani Andrade; Dolmans, Marie-Madeleine; David, Anu; Jaeger, Jonathan; Vanacker, Julie; Camboni, Alessandra; Donnez, Jacques; Van Langendonckt, Anne

    2012-11-01

    To assess the efficiency of two vitrification protocols to cryopreserve human preantral follicles with the use of a xenografting model. Pilot study. Gynecology research unit in a university hospital. Ovarian biopsies were obtained from seven women aged 30-41 years. Ovarian tissue fragments were subjected to one of three cryopreservation protocols (slow freezing, vitrification protocol 1, and vitrification protocol 2) and xenografted for 1 week to nude mice. The number of morphologically normal follicles after cryopreservation and grafting and fibrotic surface area were determined by histologic analysis. Apoptosis was assessed by the TUNEL method. Morphometric analysis of TUNEL-positive surface area also was performed. Follicle proliferation was evaluated by immunohistochemistry. After xenografting, a difference was observed between the cryopreservation procedures applied. According to TUNEL analysis, both vitrification protocols showed better preservation of preantral follicles than the conventional freezing method. Moreover, histologic evaluation showed a significantly higher proportion of primordial follicles in vitrified (protocol 2)-warmed ovarian tissue than in frozen-thawed tissue. The proportion of growing follicles and fibrotic surface area was similar in all groups. Vitrification procedures appeared to preserve not only the morphology and survival of preantral follicles after 1 week of xenografting, but also their ability to resume folliculogenesis. In addition, vitrification protocol 2 had a positive impact on the quiescent state of primordial follicles after xenografting. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Radioimmunoassay of renin in human renal tissues

    International Nuclear Information System (INIS)

    Wowra, B.

    1981-01-01

    A method has been developed to quantitatively determine renin in human kidney tissue. The angiotensin I split off angiotensinogs by renin was radioimmunologically determined. The renin-renin substrate reaction rate followed a saturation kinetics, as it increased the larger the substrate content in the incubation medium until it acquired a maximum value; the reaction rate decreased with substrate concentrations over 40 mg/ml incubation medium. The discontinuance of the renin reaction after incubation by adding acid, boiling and neutralizing again, gave highest renin values. The RIA scattering was 8.3% for double determination of the same sample, for the determination in different RIA additions 7.0%. The detection limit was 20 pg angiotensin I. A direct comparison of radioimmunoassay and bioassay exhibited a very significant agreement of both methods, where the radioimmunologically measured renin values were on average four times larger than those obtained using biological technique. The definition of the so-called normal values for absolute and specific renin concentration in human kidney tissue enabled one to assess the renin values in various syndromes. (orig./MG) [de

  2. Genetic Comparison of Stemness of Human Umbilical Cord and Dental Pulp

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    Chung-Min Kang

    2016-01-01

    Full Text Available This study focuses on gene expression patterns and functions in human umbilical cord (UC and dental pulp (DP containing mesenchymal stem cells (MSCs. DP tissues were collected from 25 permanent premolars. UC tissue samples were obtained from three newborns. Comparative gene profiles were obtained using cDNA microarray analysis and the expression of tooth development-associated and MSC-related genes was assessed by the quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR. Genes related to cell proliferation, angiogenesis, and immune responses were expressed at higher levels in UC, whereas genes related to growth factor and receptor activity and signal transduction were more highly expressed in DP. Although UC and DP tissues exhibited similar expression of surface markers for MSCs, UC showed higher expression of CD29, CD34, CD44, CD73, CD105, CD146, and CD166. qRT-PCR analysis showed that CD146, CD166, and MYC were expressed 18.3, 8.24, and 1.63 times more highly in UC, whereas the expression of CD34 was 2.15 times higher in DP. Immunohistochemical staining revealed significant differences in the expression of genes (DSPP, DMP1, and CALB1 related to odontogenesis and angiogenesis in DP. DP and UC tissue showed similar gene expression, with the usual MSC markers, while they clearly diverged in their differentiation capacity.

  3. Genetic Comparison of Stemness of Human Umbilical Cord and Dental Pulp.

    Science.gov (United States)

    Kang, Chung-Min; Kim, Hyunok; Song, Je Seon; Choi, Byung-Jai; Kim, Seong-Oh; Jung, Han-Sung; Moon, Seok-Jun; Choi, Hyung-Jun

    2016-01-01

    This study focuses on gene expression patterns and functions in human umbilical cord (UC) and dental pulp (DP) containing mesenchymal stem cells (MSCs). DP tissues were collected from 25 permanent premolars. UC tissue samples were obtained from three newborns. Comparative gene profiles were obtained using cDNA microarray analysis and the expression of tooth development-associated and MSC-related genes was assessed by the quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Genes related to cell proliferation, angiogenesis, and immune responses were expressed at higher levels in UC, whereas genes related to growth factor and receptor activity and signal transduction were more highly expressed in DP. Although UC and DP tissues exhibited similar expression of surface markers for MSCs, UC showed higher expression of CD29, CD34, CD44, CD73, CD105, CD146, and CD166. qRT-PCR analysis showed that CD146, CD166, and MYC were expressed 18.3, 8.24, and 1.63 times more highly in UC, whereas the expression of CD34 was 2.15 times higher in DP. Immunohistochemical staining revealed significant differences in the expression of genes (DSPP, DMP1, and CALB1) related to odontogenesis and angiogenesis in DP. DP and UC tissue showed similar gene expression, with the usual MSC markers, while they clearly diverged in their differentiation capacity.

  4. The Regulatory Effects of Long Noncoding RNA-ANCR on Dental Tissue-Derived Stem Cells

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    Qian Jia

    2016-01-01

    Full Text Available Long noncoding RNAs (lncRNA have been recognized as important regulators in diverse biological processes, such as transcriptional regulation, stem cell proliferation, and differentiation. Previous study has demonstrated that lncRNA-ANCR (antidifferentiation ncRNA plays a key role in regulating the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs. However, little is known about the role of ANCR in regulating other types of dental tissue-derived stem cells (DTSCs behaviours (including proliferation and multiple-potential of differentiation. In this study, we investigated the regulatory effects of lncRNA-ANCR on the proliferation and differentiation (including osteogenic, adipogenic, and neurogenic differentiation of DTSCs, including dental pulp stem cells (DPSCs, PDLSCs, and stem cells from the apical papilla (SCAP by downregulation of lncRNA-ANCR. We found that downregulation of ANCR exerted little effect on proliferation of DPSCs and SCAP but promoted the osteogenic, adipogenic, and neurogenic differentiation of DTSCs. These data provide an insight into the regulatory effects of long noncoding RNA-ANCR on DTSCs and indicate that ANCR is a very important regulatory factor in stem cell differentiation.

  5. Encapsulated dental-derived mesenchymal stem cells in an injectable and biodegradable scaffold for applications in bone tissue engineering.

    Science.gov (United States)

    Moshaverinia, Alireza; Chen, Chider; Akiyama, Kentaro; Xu, Xingtian; Chee, Winston W L; Schricker, Scott R; Shi, Songtao

    2013-11-01

    Bone grafts are currently the major family of treatment options in modern reconstructive dentistry. As an alternative, stem cell-scaffold constructs seem to hold promise for bone tissue engineering. However, the feasibility of encapsulating dental-derived mesenchymal stem cells in scaffold biomaterials such as alginate hydrogel remains to be tested. The objectives of this study were, therefore, to: (1) develop an injectable scaffold based on oxidized alginate microbeads encapsulating periodontal ligament stem cells (PDLSCs) and gingival mesenchymal stem cells (GMSCs); and (2) investigate the cell viability and osteogenic differentiation of the stem cells in the microbeads both in vitro and in vivo. Microbeads with diameters of 1 ± 0.1 mm were fabricated with 2 × 10(6) stem cells/mL of alginate. Microbeads containing PDLSCs, GMSCs, and human bone marrow mesenchymal stem cells as a positive control were implanted subcutaneously and ectopic bone formation was analyzed by micro CT and histological analysis at 8-weeks postimplantation. The encapsulated stem cells remained viable after 4 weeks of culturing in osteo-differentiating induction medium. Scanning electron microscopy and X-ray diffraction results confirmed that apatitic mineral was deposited by the stem cells. In vivo, ectopic mineralization was observed inside and around the implanted microbeads containing the immobilized stem cells. These findings demonstrate for the first time that immobilization of PDLSCs and GMSCs in alginate microbeads provides a promising strategy for bone tissue engineering. Copyright © 2013 Wiley Periodicals, Inc.

  6. Coefficient of Friction of Human Corneal Tissue.

    Science.gov (United States)

    Wilson, Tawnya; Aeschlimann, Rudolf; Tosatti, Samuele; Toubouti, Youssef; Kakkassery, Joseph; Osborn Lorenz, Katherine

    2015-09-01

    A novel property evaluation methodology was used to determine the elusive value for the human corneal coefficient of friction (CoF). Using a microtribometer on 28 fresh human donor corneas with intact epithelia, the CoF was determined in 4 test solutions (≥5 corneas/solution): tear-mimicking solution (TMS) in borate-buffered saline (TMS-PS), TMS in phosphate-buffered saline (TMS-PBS), TMS with HEPES-buffered saline (TMS-HEPES), and tear-like fluid in PBS (TLF-PBS). Mean (SD) CoF values ranged from 0.006 to 0.015 and were 0.013 (0.010) in TMS-PS, 0.006 (0.003) in TMS-PBS, 0.014 (0.005) in TMS-HEPES, and 0.015 (0.009) in TLF-PBS. Statistically significant differences were shown for TMS-PBS versus TLF (P = 0.0424) and TMS-PBS versus TMS-HEPES (P = 0.0179), but not for TMS-PBS versus TMS-PS (P = 0.2389). Successful measurement of the fresh human corneal tissue CoF was demonstrated, with values differing in the evaluated buffer solutions, within this limited sample size.

  7. Precise femtosecond laser ablation of dental hard tissue: preliminary investigation on adequate laser parameters

    International Nuclear Information System (INIS)

    Hikov, Todor; Pecheva, Emilia; Petrov, Todor; Montgomery, Paul; Antoni, Frederic; Leong-Hoi, Audrey

    2017-01-01

    This work aims at evaluating the possibility of introducing state-of-the-art commercial femtosecond laser system in restorative dentistry by maintaining well-known benefits of lasers for caries removal, but also in overcoming disadvantages such as thermal damage of irradiated substrate. Femtosecond ablation of dental hard tissue is investigated by changing the irradiation parameters (pulsed laser energy, scanning speed and pulse repetition rate), assessed for enamel and dentin. The femtosecond laser system used in this work may be suitable for cavity preparation in dentin and enamel, due to the expected effective ablation and low temperature increase when using ultra short laser pulses. If adequate laser parameters are selected, this system seems to be promising for promoting a laser-assisted, minimally invasive approach in restorative dentistry. (paper)

  8. Incremental growth of therizinosaurian dental tissues: implications for dietary transitions in Theropoda

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    Khai Button

    2017-12-01

    Full Text Available Previous investigations document functional and phylogenetic signals in the histology of dinosaur teeth. In particular, incremental lines in dentin have been used to determine tooth growth and replacement rates in several dinosaurian clades. However, to date, few studies have investigated the dental microstructure of theropods in the omnivory/herbivory spectrum. Here we examine dental histology of Therizinosauria, a clade of large-bodied theropods bearing significant morphological evidence for herbivory, by examining the teeth of the early-diverging therizinosaurian Falcarius utahensis, and an isolated tooth referred to Suzhousaurus megatherioides, a highly specialized large-bodied representative. Despite attaining some of the largest body masses among maniraptoran theropod dinosaurs, therizinosaurian teeth are diminutive, measuring no more than 0.90 cm in crown height (CH and 0.38 cm in crown base length (CBL. Comparisons with other theropods and non-theropodan herbivorous dinosaurs reveals that when controlling for estimated body mass, crown volume in therizinosaurians plots most closely with dinosaurs of similar dietary strategy as opposed to phylogenetic heritage. Analysis of incremental growth lines in dentin, observed in thin sections of therizinosaurian teeth, demonstrates that tooth growth rates fall within the range of other archosaurs, conforming to hypothesized physiological limitations on the production of dental tissues. Despite dietary differences between therizinosaurians and hypercarnivorous theropods, the types of enamel crystallites present and their spatial distribution—i.e., the schmelzmuster of both taxa—is limited to parallel enamel crystallites, the simplest form of enamel and the plesiomorphic condition for Theropoda. This finding supports previous hypotheses that dental microstructure is strongly influenced by phylogeny, yet equally supports suggestions of reduced reliance on oral processing in omnivorous

  9. Age-related changes of dental pulp tissue after experimental tooth movement in rats

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    Martina Von Böhl

    2016-01-01

    Full Text Available It is generally accepted that the effect of orthodontic tooth movement on the dental pulp in adolescents is reversible and that it has no long-lasting effect on pulpal physiology. However, it is not clear yet if the same conclusion is also valid for adult subjects. Thus, in two groups of rats, aged 6 and 40 weeks respectively, 3 molars at one side of the maxilla were moved together in a mesial direction with a standardized orthodontic appliance delivering a force of 10 cN. The contralateral side served as a control. Parasagittal histological sections were prepared after tooth movement for 1, 2, 4, 8, and 12 weeks. The pulp tissue was characterized for the different groups, with special emphasis on cell density, inflammatory cells, vascularity, and odontoblasts. Dimensions of dentin and the pulpal horns was determined and related with the duration of orthodontic force application and age ware evaluated. We found that neither in young nor in adult rats, force application led to long-lasting or irreversible changes in pulpal tissues. Dimensional variables showed significant age-related changes. In conclusion, orthodontic tooth movement per se has no long-lasting or irreversible effect on pulpal tissues, neither in the young nor in the adult animals.

  10. Proteome of human stem cells from periodontal ligament and dental pulp.

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    Enrica Eleuterio

    Full Text Available BACKGROUND: Many adult tissues contain a population of stem cells with the ability to regenerate structures similar to the microenvironments from which they are derived in vivo and represent a promising therapy for the regeneration of complex tissues in the clinical disorder. Human adult stem cells (SCs including bone marrow stem cells (BMSCs, dental pulp stem cells (DPSCs and periodontal ligament stem cells (PDLSCs have been characterized for their high proliferative potential, expression of characteristic SC-associated markers and for the plasticity to differentiate in different lineage in vitro. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study is to define the molecular features of stem cells from oral tissue by comparing the proteomic profiles obtained with 2-DE followed by MALDI-TOF/TOF of ex-vivo cultured human PDLSCs, DPSCs and BMSCs. Our results showed qualitative similarities in the proteome profiles among the SCs examined including some significant quantitative differences. To enrich the knowledge of oral SCs proteome we performed an analysis in narrow range pH 4-7 and 6-9, and we found that DPSCs vs PDLSCs express differentially regulated proteins that are potentially related to growth, regulation and genesis of neuronal cells, suggesting that SCs derived from oral tissue source populations may possess the potential ability of neuronal differentiation which is very consistent with their neural crest origin. CONCLUSION/SIGNIFICANCE: This study identifies some differentially expressed proteins by using comparative analysis between DPSCs and PDLSCs and BMSCs and suggests that stem cells from oral tissue could have a different cell lineage potency compared to BMSCs.

  11. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

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    Jorge Luis Montenegro Raudales

    Full Text Available Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs, and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs and peripheral blood mononuclear cells (PBMCs with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a

  12. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes.

    Science.gov (United States)

    Montenegro Raudales, Jorge Luis; Yoshimura, Atsutoshi; Sm, Ziauddin; Kaneko, Takashi; Ozaki, Yukio; Ukai, Takashi; Miyazaki, Toshihiro; Latz, Eicke; Hara, Yoshitaka

    2016-01-01

    Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs), and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a partial role in

  13. Dental Calculus Stimulates Interleukin-1β Secretion by Activating NLRP3 Inflammasome in Human and Mouse Phagocytes

    Science.gov (United States)

    Montenegro Raudales, Jorge Luis; Yoshimura, Atsutoshi; SM, Ziauddin; Kaneko, Takashi; Ozaki, Yukio; Ukai, Takashi; Miyazaki, Toshihiro; Latz, Eicke; Hara, Yoshitaka

    2016-01-01

    Dental calculus is a mineralized deposit associated with periodontitis. The bacterial components contained in dental calculus can be recognized by host immune sensors, such as Toll-like receptors (TLRs), and induce transcription of proinflammatory cytokines, such as IL-1β. Studies have shown that cellular uptake of crystalline particles may trigger NLRP3 inflammasome activation, leading to the cleavage of the IL-1β precursor to its mature form. Phagocytosis of dental calculus in the periodontal pocket may therefore lead to the secretion of IL-1β, promoting inflammatory responses in periodontal tissues. However, the capacity of dental calculus to induce IL-1β secretion in human phagocytes has not been explored. To study this, we stimulated human polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) with dental calculus collected from periodontitis patients, and measured IL-1β secretion by ELISA. We found that calculus induced IL-1β secretion in both human PMNs and PBMCs. Calculus also induced IL-1β in macrophages from wild-type mice, but not in macrophages from NLRP3- and ASC-deficient mice, indicating the involvement of NLRP3 and ASC. IL-1β induction was inhibited by polymyxin B, suggesting that LPS is one of the components of calculus that induces pro-IL-1β transcription. To analyze the effect of the inorganic structure, we baked calculus at 250°C for 1 h. This baked calculus failed to induce pro-IL-1β transcription. However, it did induce IL-1β secretion in lipid A-primed cells, indicating that the crystalline structure of calculus induces inflammasome activation. Furthermore, hydroxyapatite crystals, a component of dental calculus, induced IL-1β in mouse macrophages, and baked calculus induced IL-1β in lipid A-primed human PMNs and PBMCs. These results indicate that dental calculus stimulates IL-1β secretion via NLRP3 inflammasome in human and mouse phagocytes, and that the crystalline structure has a partial role in

  14. Effect of dental restoration with epoxy and bioceramic paste on periodontal tissue damage

    Institute of Scientific and Technical Information of China (English)

    Nan-Lin Meng

    2017-01-01

    Objective:To study the effect of dental restoration with epoxy and bioceramic paste on periodontal tissue damage.Methods: Patients with pulpal and periapical diseases who received root canal therapy in our hospital between May 2013 and October 2016 were retrospectively analyzed, and according to the different root canal filling materials they used, they were divided into epoxy group and bioceramic group who used epoxy paste and bioceramic paste as root canal filling materials respectively. Before and after treatment, gingival crevicular fluid was collected respectively to determine the levels of inflammatory factors, oxidative stress products, cell apoptosis molecules and protease-related molecules.Results: 2 weeks after treatment, IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bcl-2, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1, MMP-2, TIMP-1 and TIMP-2 levels in gingival crevicular fluid of epoxy group were not significantly different from those before treatment; IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1 and MMP-2 levels in gingival crevicular fluid of bioceramic group were significantly higher than those before treatment while Bcl-2, TIMP-1 and TIMP-2 levels were significantly lower than those before treatment; IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bcl-2, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1, MMP-2, TIMP-1 and TIMP-2 levels in gingival crevicular fluid were significantly different between two groups of patients after treatment.Conclusion:Epoxy paste for dental restoration causes less damage to periodontal tissue than bioceramic paste.

  15. Chronic radiation effects on dental hard tissue (''radiation carries''). Classification and therapeutic strategies

    International Nuclear Information System (INIS)

    Groetz, K.A.; Brahm, R.; Al-Nawas, B.; Wagner, W.; Riesenbeck, D.; Willich, N.; Seegenschmiedt, M.H.

    2001-01-01

    Objectives: Since the first description of rapid destruction of dental hard tissues following head and neck radiotherapy 80 years ago, 'radiation caries' is an established clinical finding. The internationally accepted clinical evaluation score RTOG/EORTC however is lacking a classification of this frequent radiogenic alteration. Material and Methods: Medical records, data and images of radiation effects on the teeth of more than 1,500 patients, who underwent periradiotherapeutic care, were analyzed. Macroscopic alterations regarding the grade of late lesions of tooth crowns were used for a classification into 4 grades according to the RTOG/EORTC guidelines. Results: No early radiation effects were found by macroscopic inspection. In the first 90 days following radiotherapy 1/3 of the patients complained of reversible hypersensitivity, which may be related to a temporary hyperemia of the pulp. It was possible to classify radiation caries as a late radiation effect on a graded scale as known from RTOG/EORTC for other organ systems. This is a prerequisite for the integration of radiation caries into the international nomenclature of the RTOG/EORTC classification. Conclusions: The documentation of early radiation effects on dental hard tissues seems to be neglectable. On the other hand the documentation of late radiation effects has a high clinical impact. The identification of an initial lesion at the high-risk areas of the neck and incisal part of the tooth can lead to a successful therapy as a major prerequisite for orofacial rehabilitation. An internationally standardized documentation is a basis for the evaluation of the side effects of radiooncotic therapy as well as the effectiveness of protective and supportive procedures. (orig.) [de

  16. Effect of dental restoration with epoxy and bioceramic paste on periodontal tissue damage

    Directory of Open Access Journals (Sweden)

    Nan-Lin Meng

    2017-05-01

    Full Text Available Objective: To study the effect of dental restoration with epoxy and bioceramic paste on periodontal tissue damage. Methods: Patients with pulpal and periapical diseases who received root canal therapy in our hospital between May 2013 and October 2016 were retrospectively analyzed, and according to the different root canal filling materials they used, they were divided into epoxy group and bioceramic group who used epoxy paste and bioceramic paste as root canal filling materials respectively. Before and after treatment, gingival crevicular fluid was collected respectively to determine the levels of inflammatory factors, oxidative stress products, cell apoptosis molecules and protease-related molecules. Results: 2 weeks after treatment, IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bcl-2, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1, MMP-2, TIMP-1 and TIMP-2 levels in gingival crevicular fluid of epoxy group were not significantly different from those before treatment; IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1 and MMP-2 levels in gingival crevicular fluid of bioceramic group were significantly higher than those before treatment while Bcl-2, TIMP-1 and TIMP-2 levels were significantly lower than those before treatment; IL-1β, IL-6, CRP, ROS, MDA, AOPP, Bcl-2, Bax, Cyt-C, caspase-3, Smac, EMMPRIN, MMP-1, MMP-2, TIMP-1 and TIMP-2 levels in gingival crevicular fluid were significantly different between two groups of patients after treatment. Conclusion: Epoxy paste for dental restoration causes less damage to periodontal tissue than bioceramic paste.

  17. Concomitant multipotent and unipotent dental pulp progenitors and their respective contribution to mineralised tissue formation

    Directory of Open Access Journals (Sweden)

    S Dimitrova-Nakov

    2012-05-01

    Full Text Available Upon in vitro induction or in vivo implantation, the stem cells of the dental pulp display hallmarks of odontoblastic, osteogenic, adipogenic or neuronal cells. However, whether these phenotypes result from genuine multipotent cells or from coexistence of distinct progenitors is still an open question. Furthermore, determining whether a single cell-derived progenitor is capable of undergoing a differentiation cascade leading to tissue repair in situ is important for the development of cell therapy strategies. Three clonal pulp precursor cell lines (A4, C5, H8, established from embryonic ED18 first molars of mouse transgenic for a recombinant plasmid adeno-SV40, were induced to differentiate towards the odonto/osteogenic, chondrogenic or adipogenic programme. Expression of phenotypic markers of each lineage was evaluated by RT-PCR, histochemistry or immunocytochemistry. The clones were implanted into mandibular incisors or calvaria of adult mice. The A4 clone was capable of being recruited towards at least 3 mesodermal lineages in vitro and of contributing to dentin-like or bone formation, in vivo, thus behaving as a multipotent cell. In contrast, the C5 and H8 clones displayed a more restricted potential. Flow cytometric analysis revealed that isolated monopotent and multipotent clones could be distinguished by a differential expression of CD90. Altogether, isolation of these clonal lines allowed demonstrating the coexistence of multipotential and restricted-lineage progenitors in the mouse pulp. These cells may further permit unravelling specificities of the different types of pulp progenitors, hence facilitating the development of cell-based therapies of the dental pulp or other cranio-facial tissues.

  18. Cell death effects of resin-based dental material compounds and mercurials in human gingival fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Reichl, Franz-Xaver [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany); Esters, Magali; Simon, Sabine; Seiss, Mario [Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Kehe, Kai [Bundeswehr Institute of Pharmacology and Toxicology, Munich (Germany); Kleinsasser, Norbert [University of Regensburg, Head and Neck Surgery, Department of Otolaryngology, Regensburg (Germany); Folwaczny, Matthias; Glas, Juergen; Hickel, Reinhard [Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany)

    2006-06-15

    In order to test the hypothesis that released dental restorative materials can reach toxic levels in human oral tissues, the cytotoxicities of the resin-based dental (co)monomers hydroxyethylmethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and bisglycidylmethacrylate (BisGMA) compared with methyl mercury chloride (MeHgCl) and the amalgam component mercuric chloride (HgCl{sub 2}) were investigated on human gingival fibroblasts (HGF) using two different test systems: (1) the modified XTT-test and (2) the modified H 33342 staining assay. The HGF were exposed to various concentrations of the test-substances in all test systems for 24 h. All tested (co)monomers and mercury compounds significantly (P<0.05) decreased the formazan formation in the XTT-test. EC{sub 50} values in the XTT assay were obtained as half-maximum-effect concentrations from fitted curves. Following EC{sub 50} values were found (mean [mmol/l]; s.e.m. in parentheses; n=12; * significantly different to HEMA): HEMA 11.530 (0.600); TEGDMA* 3.460 (0.200); UDMA* 0.106 (0.005); BisGMA* 0.087 (0.001); HgCl{sub 2}* 0.013 (0.001); MeHgCl* 0.005 (0.001). Following relative toxicities were found: HEMA 1; TEGDMA 3; UDMA 109; BisGMA 133; HgCl{sub 2} 887; MeHgCl 2306. A significant (P<0.05) increase of the toxicity of (co)monomers and mercurials was found in the XTT-test in the following order: HEMA < TEGDMA < UDMA < BisGMA < HgCl{sub 2} < MeHgCl. TEGDMA and MeHgCl induced mainly apoptotic cell death. HEMA, UDMA, BisGMA, and HgCl{sub 2} induced mainly necrotic cell death. The results of this study indicate that resin composite components have a lower toxicity than mercury from amalgam in HGF. HEMA, BisGMA, UDMA, and HgCl{sub 2} induced mainly necrosis, but it is rather unlikely that eluted substances (solely) can reach concentrations, which might induce necrotic cell death in the human physiological situation, indicating that other (additional) factors may be involved in

  19. Plasticity of human dental pulp stromal cells with bioengineering platforms: a versatile tool for regenerative medicine.

    Science.gov (United States)

    Barachini, Serena; Danti, Serena; Pacini, Simone; D'Alessandro, Delfo; Carnicelli, Vittoria; Trombi, Luisa; Moscato, Stefania; Mannari, Claudio; Cei, Silvia; Petrini, Mario

    2014-12-01

    In recent years, human dental pulp stromal cells (DPSCs) have received growing attention due to their characteristics in common with other mesenchymal stem cells, in addition to the ease with which they can be harvested. In this study, we demonstrated that the isolation of DPSCs from third molar teeth of healthy individuals allowed the recovery of dental mesenchymal stem cells that showed self-renewal and multipotent differentiation capability. DPSCs resulted positive for CD73, CD90, CD105, STRO-1, negative for CD34, CD45, CD14 and were able to differentiate into osteogenic and chondrogenic cells. We also assayed the angiogenic potential of DPSCs, their capillary tube-like formation was assessed using an in vitro angiogenesis assay and the uptake of acetylated low-density lipoprotein was measured as a marker of endothelial function. Based on these results, DPSCs were capable of differentiating into cells with phenotypic and functional features of endothelial cells. Furthermore, this study investigated the growth and differentiation of human DPSCs under a variety of bioengineering platforms, such as low frequency ultrasounds, tissue engineering and nanomaterials. DPSCs showed an enhanced chondrogenic differentiation under ultrasound application. Moreover, DPSCs were tested on different scaffolds, poly(vinyl alcohol)/gelatin (PVA/G) sponges and human plasma clots. We showed that both PVA/G and human plasma clot are suitable scaffolds for adhesion, growth and differentiation of DPSCs toward osteoblastic lineages. Finally, we evaluated the interactions of DPSCs with a novel class of nanomaterials, namely boron nitride nanotubes (BNNTs). From our investigation, DPSCs have appeared as a highly versatile cellular tool to be employed in regenerative medicine. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Microarray evaluation of gene expression profiles in inflamed and healthy human dental pulp: the role of IL1beta and CD40 in pulp inflammation.

    Science.gov (United States)

    Gatta, V; Zizzari, V L; Dd ' Amico, V; Salini, L; D' Aurora, M; Franchi, S; Antonucci, I; Sberna, M T; Gherlone, E; Stuppia, L; Tetè, S

    2012-01-01

    Dental pulp undergoes a number of changes passing from healthy status to inflammation due to deep decay. These changes are regulated by several genes resulting differently expressed in inflamed and healthy dental pulp, and the knowledge of the processes underlying this differential expression is of great relevance in the identification of the pathogenesis of the disease. In this study, the gene expression profile of inflamed and healthy dental pulps were compared by microarray analysis, and data obtained were analyzed by Ingenuity Pathway Analysis (IPA) software. This analysis allows to focus on a variety of genes, typically expressed in inflamed tissues. The comparison analysis showed an increased expression of several genes in inflamed pulp, among which IL1β and CD40 resulted of particular interest. These results indicate that gene expression profile of human dental pulp in different physiological and pathological conditions may become an useful tool for improving our knowledge about processes regulating pulp inflammation.

  1. Soft tissue management for dental implants: what are the most effective techniques? A Cochrane systematic review.

    Science.gov (United States)

    Esposito, Marco; Maghaireh, Hassan; Grusovin, Maria Gabriella; Ziounas, Ioannis; Worthington, Helen V

    2012-01-01

    This review is based on a Cochrane systematic review entitled 'Interventions for replacing missing teeth: management of soft tissues for dental implants' published in The Cochrane Library (see http:// www.cochrane.org/ for information). Cochrane systematic reviews are regularly updated to include new research, and in response to comments and criticisms from readers. If you wish to comment on this review, please send your comments to the Cochrane website or to Marco Esposito. The Cochrane Library should be consulted for the most recent version of the review. The results of a Cochrane review can be interpreted differently, depending on people's perspectives and circumstances. Please consider the conclusions presented carefully. They are the opinions of the review authors, and are not necessarily shared by the Cochrane Collaboration. To evaluate whether flapless procedures are beneficial for patients and which is the ideal flap design, whether soft tissue correction/augmentation techniques are beneficial for patients and which are the best techniques, whether techniques to increase the peri-implant keratinised mucosa are beneficial for patients and which are the best techniques, and which are the best suturing techniques/ materials. The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched up to the 9th of June 2011 for randomised controlled trials (RCTs) of rootform osseointegrated dental implants, with a follow-up of at least 6 months after function, comparing various techniques to handle soft tissues in relation to dental implants. Primary outcome measures were prosthetic failures, implant failures and biological complications. Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted at least in duplicate and independently by two or more review authors. The statistical unit was the patient and not the prosthesis, the procedure or the implant. RESULTS were expressed

  2. Characteristics of dental pulp in human upper first premolar teeth based on immunohistochemical and morphometric examinations.

    Science.gov (United States)

    Tomaszewska, Joanna Maria; Miskowiak, Bogdan; Matthews-Brzozowska, Teresa; Wierzbicki, Piotr

    2013-01-01

    Teeth extracted for orthodontic reasons are commonly considered as healthy. Therefore, it is possible to examine structure of the dental pulp can be fully recognized and how it is affected by malocclusion. The aim of the study was to evaluate by immunohistochemistry (IHC) and morphometry dental pulp in human upper first premolar teeth extracted for orthodontic reasons. The material comprised 36 teeth of 20 patients in the age range 16-26 years. By the use of IHC markers the presence of immunocompetent cells (CD20, CD45RO, and CD68), blood vessels (CD31) and nerves (PGP9.5) were examined in the pulp. Inflammatory infiltrates and tissue atrophy were observed in 24 and 10 teeth, respectively. Strong positive correlation between the width of the odontoblastic layer, the number of rows of odontoblast nuclei and the increase of MVA (microvessel area) in the pulp of atrophic teeth was found. The cellular infiltrations found in H&E-stained sections were identified by IHC as memory T cells (CD45RO+) and B lymphocytes (CD20+) with macrophages (CD68+) present at the periphery. The CD20 antigen was intensively expressed in 13 teeth, CD45RO in 33 teeth, and CD68 in 20 teeth. Thus, despite the lack of any clinical signs of pulp disease many teeth extracted for orthodontic reasons show focal pulp inflammation and atrophy which probably results from the malocclusion stress accompanying teeth crowding.

  3. Cellular Responses in Human Dental Pulp Stem Cells Treated with Three Endodontic Materials

    Directory of Open Access Journals (Sweden)

    Alejandro Victoria-Escandell

    2017-01-01

    Full Text Available Human dental pulp stem cells (HDPSCs are of special relevance in future regenerative dental therapies. Characterizing cytotoxicity and genotoxicity produced by endodontic materials is required to evaluate the potential for regeneration of injured tissues in future strategies combining regenerative and root canal therapies. This study explores the cytotoxicity and genotoxicity mediated by oxidative stress of three endodontic materials that are widely used on HDPSCs: a mineral trioxide aggregate (MTA-Angelus white, an epoxy resin sealant (AH-Plus cement, and an MTA-based cement sealer (MTA-Fillapex. Cell viability and cell death rate were assessed by flow cytometry. Oxidative stress was measured by OxyBlot. Levels of antioxidant enzymes were evaluated by Western blot. Genotoxicity was studied by quantifying the expression levels of DNA damage sensors such as ATM and RAD53 genes and DNA damage repair sensors such as RAD51 and PARP-1. Results indicate that AH-Plus increased apoptosis, oxidative stress, and genotoxicity markers in HDPSCs. MTA-Fillapex was the most cytotoxic oxidative stress inductor and genotoxic material for HDPSCs at longer times in preincubated cell culture medium, and MTA-Angelus was less cytotoxic and genotoxic than AH-Plus and MTA-Fillapex at all times assayed.

  4. Capacity of Human Dental Follicle Cells to Differentiate into Neural Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Shingo Kanao

    2017-01-01

    Full Text Available The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. Human dental follicle cells (hDFCs have the capacity to commit to differentiation into multiple cell types. Here we investigated the capacity of hDFCs to differentiate into neural cells and the efficiency of a two-step strategy involving floating neurosphere-like bodies for neural differentiation. Undifferentiated hDFCs showed a spindle-like morphology and were positive for neural markers such as nestin, β-III-tubulin, and S100β. The cellular morphology of several cells was neuronal-like including branched dendrite-like processes and neurites. Next, hDFCs were used for neurosphere formation in serum-free medium containing basic fibroblast growth factor, epidermal growth factor, and B27 supplement. The number of cells with neuronal-like morphology and that were strongly positive for neural markers increased with sphere formation. Gene expression of neural markers also increased in hDFCs with sphere formation. Next, gene expression of neural markers was examined in hDFCs during neuronal differentiation after sphere formation. Expression of Musashi-1 and Musashi-2, MAP2, GFAP, MBP, and SOX10 was upregulated in hDFCs undergoing neuronal differentiation via neurospheres, whereas expression of nestin and β-III-tubulin was downregulated. In conclusion, hDFCs may be another optimal source of neural/glial cells for cell-based therapies to treat neurological diseases.

  5. Glycometabolic reprogramming associated with the initiation of human dental pulp stem cell differentiation.

    Science.gov (United States)

    Wang, Linyan; Cheng, Li; Wang, Huning; Pan, Hongying; Yang, Hui; Shao, Meiying; Hu, Tao

    2016-03-01

    Glycometabolism, particularly mitochondrial oxidative phosphorylation (OXPHOS) and glycolysis, plays a central role in cell life activities. Glycometabolism can be reprogrammed to maintain the stemness or to induce the differentiation of stem cells, thereby regulating tissue repair and regeneration. However, research on the glycometabolism of human dental pulp stem cells (hDPSCs) remains scarce. Here, we investigated the relationship between glycometabolic reprogramming and initiation of hDPSC differentiation. We found the differentiation of hDPSCs commenced on day 3 when cells were cultured in mineralized medium. When cell differentiation commenced, mitochondria became elongated with well-developed cristae, and the oxygen consumption rate of mitochondria was enhanced, manifested as an increase in basal respiration, mitochondrial ATP production, and maximal respiration. Interestingly, glycolytic enzyme activities, glycolysis capacity, and glycolysis reserve were also upregulated at this time to match the powerful bioenergetic demands. More importantly, hDPSCs derived from different donors or cultured in various oxygen environments showed similar glycometabolic changes when they began to differentiate. Thus, glycometabolic reprogramming accompanies initiation of hDPSC differentiation and could potentially play a role in the regulation of dental pulp repair. © 2015 International Federation for Cell Biology.

  6. Novel approach for transient protein expression in primary cultures of human dental pulp-derived cells.

    Science.gov (United States)

    Suguro, Hisashi; Mikami, Yoshikazu; Koshi, Rieko; Ogiso, Bunnai; Watanabe, Eri; Watanabe, Nobukazu; Honda, Masaki J; Asano, Masatake; Komiyama, Kazuo

    2011-08-01

    Transfection is a powerful method for investigating variable biological functions of desired genes. However, the efficiency of transfection into primary cultures of dental pulp-derived cells (DPDC) is low. Therefore, using a recombinant vaccinia virus (vTF7-3), which contains T7 RNA polymerase, we have established a transient protein expression system in DPDCs. In this study, we used the human polymeric immunoglobulin receptor (pIgR) cDNA as a model gene. pIgR expression by the vTF7-3 expression system was confirmed by flow cytometry analysis and Western blotting. Furthermore, exogenous pIgR protein localized at the cell surface in DPDCs and formed a secretory component (SC). This suggests that exogenous pIgR protein expressed by the vTF7-3 expression system acts like endogenous pIgR protein. These results indicate the applicability of the method for cells outgrown from dental pulp tissue. In addition, as protein expression could be detected shortly after transfection (approximately 5h), this experimental system has been used intensely for experiments examining very early steps in protein exocytosis. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Polarized spectral features of human breast tissues through wavelet ...

    Indian Academy of Sciences (India)

    Abstract. Fluorescence characteristics of human breast tissues are investigated through wavelet transform and principal component analysis (PCA). Wavelet transform of polar- ized fluorescence spectra of human breast tissues is found to localize spectral features that can reliably differentiate different tissue types.

  8. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    Science.gov (United States)

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  9. Evaluation of erbium:YAG and holmium:YAG laser radiation and dental hard tissue

    Science.gov (United States)

    Attrill, David Cameron

    Lasers have become increasingly established in medicine as effective alternatives or adjuncts to conventional techniques. In dentistry, several clinical laser systems have been developed and marketed, but their applications have been limited to soft tissue surgery. To date, no laser has been capable of effectively cutting or modifying the highly mineralised dental tissues of enamel and dentine. The aim of this study was to evaluate two new laser systems for use in dentistry through a series of in vitro experiments. Both generic erbium and holmium lasers have theoretically superior operating characteristics over currently established lasers for applications with dental hard tissues. The two lasers investigated in this study were pulsed Er:YAG (lambda=2.94) a.m. and Cr-Tm-Ho:YAG (lambda=2.1mu.m). Both operated with a macropulse duration of approximately 200lambdas, at pulse repetition rates of 2-8Hz and mean pulse energies up to 230mJ. Radiation was focused using CaF[2] lenses (f=50-120mm). The lasers could be operated with or without the addition of a surface water film at the interaction site. Tissue removal efficiency was expressed as a latent heat of ablation (LHA, kJ/cm[3]) using a modification of the technique described by Charlton et al. (1990). The mean LHA's for the Er:YAG laser were 6.24kJ/cm[3] and 22.99kJ/cm[3] with dentine and enamel respectively without water, and 10.07kJ/cm[3] and 18.73kJ/cm[3] for dentine and enamel with water. The Cr-Tm-Ho:YAG laser was unable to effectively remove enamel at the fluences and pulse energies available; the mean LHA's for the Cr-Tm- Ho:YAG laser with dentine were 82.79kJ/cm3 and 57.57kJ/cm3 with and without water respectively. The Cr-Tm-Ho;YAG was approximately 8-9 times less efficient for tissue removal than the Er:YAG system. Er:YAG tissue removal with water was characterised by clean "surgical" cuts, comparable in histological appearance to those obtained using conventional instrumentation. Some thermal disruption

  10. Catalase activity in healthy and inflamed pulp tissues of permanent ...

    African Journals Online (AJOL)

    2015-11-02

    Nov 2, 2015 ... pulps, which is due to pulpitis in comparison to healthy dental pulp. Key words: .... human dental pulp cells by Porphyromonas endodontalis lipopolysaccharide. J Endod ... Biology of disease: Free radicals and tissue injury.

  11. Transplantation of Human Dental Pulp-Derived Stem Cells or Differentiated Neuronal Cells from Human Dental Pulp-Derived Stem Cells Identically Enhances Regeneration of the Injured Peripheral Nerve.

    Science.gov (United States)

    Ullah, Imran; Park, Ju-Mi; Kang, Young-Hoon; Byun, June-Ho; Kim, Dae-Geon; Kim, Joo-Heon; Kang, Dong-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-09-01

    Human dental mesenchymal stem cells isolated from the dental follicle, pulp, and root apical papilla of extracted wisdom teeth have been known to exhibit successful and potent neurogenic differentiation capacity. In particular, human dental pulp-derived stem cells (hDPSCs) stand out as the most prominent source for in vitro neuronal differentiation. In this study, to evaluate the in vivo peripheral nerve regeneration potential of hDPSCs and differentiated neuronal cells from DPSCs (DF-DPSCs), a total of 1 × 10 6 hDPSCs or DF-hDPSCs labeled with PKH26 tracking dye and supplemented with fibrin glue scaffold and collagen tubulization were transplanted into the sciatic nerve resection (5-mm gap) of rat models. At 12 weeks after cell transplantation, both hDPSC and DF-hDPSC groups showed notably increased behavioral activities and higher muscle contraction forces compared with those in the non-cell transplanted control group. In immunohistochemical analysis of regenerated nerve specimens, specific markers for angiogenesis, axonal fiber, and myelin sheath increased in both the cell transplantation groups. Pretransplanted labeled PKH26 were also distinctly detected in the regenerated nerve tissues, indicating that transplanted cells were well-preserved and differentiated into nerve cells. Furthermore, no difference was observed in the nerve regeneration potential between the hDPSC and DF-hDPSC transplanted groups. These results demonstrate that dental pulp tissue is an excellent stem cell source for nerve regeneration, and in vivo transplantation of the undifferentiated hDPSCs could exhibit sufficient and excellent peripheral nerve regeneration potential.

  12. Ethical tissue: a not-for-profit model for human tissue supply.

    Science.gov (United States)

    Adams, Kevin; Martin, Sandie

    2011-02-01

    Following legislative changes in 2004 and the establishment of the Human Tissue Authority, access to human tissues for biomedical research became a more onerous and tightly regulated process. Ethical Tissue was established to meet the growing demand for human tissues, using a process that provided ease of access by researchers whilst maintaining the highest ethical and regulatory standards. The establishment of a licensed research tissue bank entailed several key criteria covering ethical, legal, financial and logistical issues being met. A wide range of stakeholders, including the HTA, University of Bradford, flagged LREC, hospital trusts and clinical groups were also integral to the process.

  13. Tissue-based map of the human proteome

    DEFF Research Database (Denmark)

    Uhlén, Mathias; Fagerberg, Linn; Hallström, Björn M.

    2015-01-01

    Resolving the molecular details of proteome variation in the different tissues and organs of the human body will greatly increase our knowledge of human biology and disease. Here, we present a map of the human tissue proteome based on an integrated omics approach that involves quantitative transc...

  14. Enamel tissue engineering using subcultured enamel organ epithelial cells in combination with dental pulp cells.

    Science.gov (United States)

    Honda, Masaki J; Shinmura, Yuka; Shinohara, Yoshinori

    2009-01-01

    We describe a strategy for the in vitro engineering of enamel tissue using a novel technique for culturing enamel organ epithelial (EOE) cells isolated from the enamel organ using 3T3-J2 cells as a feeder layer. These subcultured EOE cells retain the capacity to produce enamel structures over a period of extended culture. In brief, enamel organs from 6-month-old porcine third molars were dissociated into single cells and subcultured on 3T3-J2 feeder cell layers. These subcultured EOE cells were then seeded onto a collagen sponge in combination with primary dental pulp cells isolated at an early stage of crown formation, and these constructs were transplanted into athymic rats. After 4 weeks, complex enamel-dentin structures were detected in the implants. These results show that our culture technique maintained ameloblast lineage cells that were able to produce enamel in vivo. This novel subculture technique provides an important tool for tooth tissue engineering. Copyright 2008 S. Karger AG, Basel.

  15. Effect of hydralazine on duration of soft tissue local anesthesia following dental treatment: a randomized clinical trial.

    Science.gov (United States)

    Fakheran Esfahani, Omid; Pouraboutaleb, Mohammad Fazel; Khorami, Behnam

    2015-01-01

    Prolonged numbness following routine dental treatments can cause difficulties in speaking and swallowing and may result in inadvertent biting of soft tissues. Local injection of vasodilator agents may represent a solution to this problem. The aim of this study was to evaluate the effect of submucosal injection of hydralazine hydrochloride (HCl) on the duration of oral soft tissue anesthesia after routine dental treatment. This randomized, single-blinded, controlled clinical trial included 50 patients who received inferior alveolar nerve block (2% lidocaine with 1:100,000 epinephrine) for simple restorative treatment. Upon completion of the dental treatment, patients randomly received a hydralazine HCl or sham injection in the same site as the local anesthetic injection. The reversal time to normal sensation of soft tissues (lips, tongue, and perioral skin) was evaluated and reported every 5 minutes by the patients, who followed an assessment protocol that they were taught in advance of treatment. Median recovery times in the hydralazine group and the sham group were 81.4 (SD, 3.6) and 221.8 (SD, 6.3) minutes, respectively. Based on Kaplan-Meier survival analysis, the duration of soft tissue anesthesia in the 2 groups was significantly different (P local anesthetic-induced soft tissue numbness and the related functional problems.

  16. Mesenchymal stem cells derived from inflamed dental pulpal and gingival tissue: a potential application for bone formation.

    Science.gov (United States)

    Tomasello, Laura; Mauceri, Rodolfo; Coppola, Antonina; Pitrone, Maria; Pizzo, Giuseppe; Campisi, Giuseppina; Pizzolanti, Giuseppe; Giordano, Carla

    2017-08-01

    Chronic periodontal disease is an infectious disease consisting of prolonged inflammation of the supporting tooth tissue and resulting in bone loss. Guided bone regeneration procedures have become common and safe treatments in dentistry, and in this context dental stem cells would represent the ideal solution as autologous cells. In this study, we verified the ability of dental pulp mesenchymal stem cells (DPSCs) and gingival mesenchymal stem cells (GMSCs) harvested from periodontally affected teeth to produce new mineralized bone tissue in vitro, and compared this to cells from healthy teeth. To characterize DPSCs and GMSCs, we assessed colony-forming assay, immunophenotyping, mesenchymal/stem cell phenotyping, stem gene profiling by means of flow cytometry, and quantitative polymerase chain reaction (qPCR). The effects of proinflammatory cytokines on mesenchymal stem cell (MSC) proliferation and differentiation potential were investigated. We also observed participation of several heat shock proteins (HSPs) and actin-depolymerizing factors (ADFs) during osteogenic differentiation. DPSCs and GMSCs were successfully isolated both from periodontally affected dental tissue and controls. Periodontally affected dental MSCs proliferated faster, and the inflamed environment did not affect MSC marker expressions. The calcium deposition was higher in periodontally affected MSCs than in the control group. Proinflammatory cytokines activate a cytoskeleton remodeling, interacting with HSPs including HSP90 and HSPA9, thioredoxin-1, and ADFs such as as profilin-1, cofilin-1, and vinculin that probably mediate the increased acquisition in the inflamed environment. Our findings provide evidence that periodontally affected dental tissue (both pulp and gingiva) can be used as a source of MSCs with intact stem cell properties. Moreover, we demonstrated that the osteogenic capability of DPSCs and GMSCs in the test group was not only preserved but increased by the overexpression of

  17. Cadmium Concentration in Human Autopsy Tissues.

    Science.gov (United States)

    Lech, Teresa; Sadlik, Józefa K

    2017-10-01

    The concentration of cadmium in human tissues obtained on the basis of autopsies of non-poisoned Polish people (n = 150), aged from 1 to 80 years, examined between 1990 and 2010, is presented. The following values were found in wet digested samples by flame atomic absorption spectrometry (FAAS) (mean ± SD, median, and range, μg/g of wet weight): brain 0.020 ± 0.031, 0.084, 0-0.120 (n = 41); stomach 0.148 ± 0.195, 0.084, 0-1.25 (n = 89); small intestine 0.227 ± 0.231, 0.130, 0-0.830 (n = 39); liver 1.54 ± 1.55, 1.01, 0.015-9.65 (n = 99); kidney 16.0 ± 13.2, 14.0, 0.62-61.3 (n = 91); lung 0.304 ± 0.414, 0.130, 0-1.90 (n = 25); and heart 0.137 ± 0.107, 0.140, 0.017-0.250 (n = 4). Additionally, results (n = 13 people, aged from 2 to 83 years, 63 samples) obtained by inductively coupled plasma optical emission spectrometry (ICP OES) between 2010 and 2015 are given. The obtained data on Cd concentration in the human body can be used to estimate the amounts occurring in "healthy" people and those occurring in cases of chronic or acute poisonings with Cd compounds, which are examined for forensic purposes or to assess environmental exposure levels.

  18. Humanism in Dental Education: A Comparison of Theory, Intention, and Stakeholder Perceptions at a North American Dental School.

    Science.gov (United States)

    Lyon, Lucinda; Itaya, Lisa E; Hoover, Terry; Booth, Mark T; Nadershahi, Nader

    2017-08-01

    In today's dental education environment, a humanistic culture is an expectation for all U.S. dental schools, codified in 2013 by its inclusion in the Commission on Dental Accreditation's standards for accreditation. The University of the Pacific Arthur A. Dugoni School of Dentistry has made an active commitment to humanism since the mid-1970s. The aim of this study was to determine how well the school's students and faculty and staff members perceived the school was living up to its formal aspirational values and who was benefitting from the humanistic culture. Using an electronic survey, data were collected from a total of 195 students, faculty members, and staff members in 2014. Respondents were 15% of the 492 full- and part-time faculty members; 9% of the total student population of 540; and 29% of 255 staff members. In the responses, humanism was described as manifest by attributes such as caring, understanding, respect, and compassion. Although the findings confirmed the value of a humanistic culture, some portions of the school's formal definition and goals, such as good work ethic, professional responsibility, high ethical standards, increasing independence, and attainment of competence, appeared less frequently in responses. Authentic assessment of institutional culture proved challenging. Focus groups offered additional ways to assess how effectively the school lives its core value of humanism. There was recognition that more varied, robust methods were needed to assess institutional alignment with stated goals for a humanistic learning environment.

  19. Transcriptomics resources of human tissues and organs

    DEFF Research Database (Denmark)

    Uhlén, Mathias; Hallström, Björn M.; Lindskog, Cecilia

    2016-01-01

    a framework for defining the molecular constituents of the human body as well as for generating comprehensive lists of proteins expressed across tissues or in a tissue-restricted manner. Here, we review publicly available human transcriptome resources and discuss body-wide data from independent genome......Quantifying the differential expression of genes in various human organs, tissues, and cell types is vital to understand human physiology and disease. Recently, several large-scale transcriptomics studies have analyzed the expression of protein-coding genes across tissues. These datasets provide...

  20. Matching the optical properties of direct esthetic dental restorative materials to those of human enamel and dentin

    Science.gov (United States)

    Ragain, James Carlton, Jr.

    One of the goals of the restorative dentist is to restore the appearance of the natural dentition. Clinical matching of teeth and restorative materials are seldom accurate and shade selection techniques are subjective. The first specific aim of this research was to characterize the optical absorption and scattering that occurs within enamel, dentin, and composite resin and compomer restorative materials and to relate those phenomena to translucency and color. The second aim was to evaluate small color differences among composite restorative materials which would be detectable by humans. The last aim was to lay the foundation for developing an improved model of specifying layers of dental restorative materials in order to match the translucency and color to those of human enamel. The Kubelka-Munk theory was validated for enamel, dentin, and the restorative materials. These tissues and materials were then characterized in terms of their color parameters. Tooth cores were also characterized in terms of color space parameters. Human subjects were evaluated for their abilities to discriminate small color differences in the dental composite resin materials. The following conclusions were derived from this study: (1) Kubelka-Munk theory accurately predicts the diffuse reflectance spectra of enamel, dentin, and the direct esthetic dental restorative materials studied. (2) Scattering and absorption coefficients of the dental tissues and esthetic restorative materials can be directly calculated from diffuse reflectance measurements of a uniformly thick slab of tissue/material using black and white backings and the appropriate refractive index. (3) For tooth cores, there is a positive correlation between L* and b* and a negative correlation between L* and a*. (4) The range of translucency parameters for the restorative materials studied does not match those of enamel and dentin. (5) None of the shades of the dental composite resin restorative materials studied fit into the

  1. Evidence of the protein content of bovine and human dental pulps by the action of endodontic irrigation solutions through electrophoretic patterns

    Directory of Open Access Journals (Sweden)

    María E López

    2013-01-01

    Full Text Available Background: Sodium dodecyl sulfate polyacrylamide gel electrophoresis let to show the protein content of different tissues. Dental pulp contains connective tissue which is removed during the endodontic treatment. Many studies consider bovine rather than human pulp tissue because of its size. Aim: To evidence the protein content of bovine and human dental pulps and the action of endodontic irrigation solutions through electrophoretic patterns. Materials and Methods: Extracts of human and bovine dental pulps were prepared. Sodium hypochlorite, calcium hydroxide, chlorhexidine and ethylenediamine tetraacetic acid were used as irrigating solutions. Results: Bovine and human pulps have a small difference in two bands of proteins present between 74 kDa and 80 kDa. The denaturizing capacity of sodium hypochlorite and the washing action of calcium hydroxide and chlorhexidine were evidenced. Ethylenediamine tetraacetic acid solution was shown to contain proteins continuously during the endodontic root canal washing. Conclusions: Differences in pulp tissues and the action of irrigating solutions on their protein content would help on the understanding of the biological process of the endodontic treatment.

  2. A Humanized Mouse Model Generated Using Surplus Neonatal Tissue

    Directory of Open Access Journals (Sweden)

    Matthew E. Brown

    2018-04-01

    Full Text Available Summary: Here, we describe the NeoThy humanized mouse model created using non-fetal human tissue sources, cryopreserved neonatal thymus and umbilical cord blood hematopoietic stem cells (HSCs. Conventional humanized mouse models are made by engrafting human fetal thymus and HSCs into immunocompromised mice. These mice harbor functional human T cells that have matured in the presence of human self-peptides and human leukocyte antigen molecules. Neonatal thymus tissue is more abundant and developmentally mature and allows for creation of up to ∼50-fold more mice per donor compared with fetal tissue models. The NeoThy has equivalent frequencies of engrafted human immune cells compared with fetal tissue humanized mice and exhibits T cell function in assays of ex vivo cell proliferation, interferon γ secretion, and in vivo graft infiltration. The NeoThy model may provide significant advantages for induced pluripotent stem cell immunogenicity studies, while bypassing the requirement for fetal tissue. : Corresponding author William Burlingham and colleagues created a humanized mouse model called the NeoThy. The NeoThy uses human neonatal, rather than fetal, tissue sources for generating a human immune system within immunocompromised mouse hosts. NeoThy mice are an attractive alternative to conventional humanized mouse models, as they enable robust and reproducible iPSC immunogenicity experiments in vivo. Keywords: NeoThy, humanized mouse, iPSC, PSC, immunogenicity, transplantation, immunology, hematopoietic stem cells, induced pluripotent stem cells, thymus

  3. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    Directory of Open Access Journals (Sweden)

    Pengfei Liu

    Full Text Available As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2 were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  4. Effects of SOX2 on Proliferation, Migration and Adhesion of Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Liu, Pengfei; Cai, Jinglei; Dong, Delu; Chen, Yaoyu; Liu, Xiaobo; Wang, Yi; Zhou, Yulai

    2015-01-01

    As a key factor for cell pluripotent and self-renewing phenotypes, SOX2 has attracted scientists' attention gradually in recent years. However, its exact effects in dental pulp stem cells (DPSCs) are still unclear. In this study, we mainly investigated whether SOX2 could affect some biological functions of DPSCs. DPSCs were isolated from the dental pulp of human impacted third molar. SOX2 overexpressing DPSCs (DPSCs-SOX2) were established through retroviral infection. The effect of SOX2 on cell proliferation, migration and adhesion ability was evaluated with CCK-8, trans-well system and fibronectin-induced cell attachment experiment respectively. Whole genome expression of DPSCs-SOX2 was analyzed with RNA microarray. Furthermore, a rescue experiment was performed with SOX2-siRNA in DPSC-SOX2 to confirm the effect of SOX2 overexpression in DPSCs. We found that SOX2 overexpression could result in the enhancement of cell proliferation, migration, and adhesion in DPSCs obviously. RNA microarray analysis indicated that some key genes in the signal pathways associated with cell cycle, migration and adhesion were upregulated in different degree, and the results were further confirmed with qPCR and western-blot. Finally, DPSC-SOX2 transfected with SOX2-siRNA showed a decrease of cell proliferation, migration and adhesion ability, which further confirmed the biological effect of SOX2 in human DPSCs. This study indicated that SOX2 could improve the cell proliferation, migration and adhesion ability of DPSCs through regulating gene expression about cell cycle, migration and adhesion, and provided a novel strategy to develop seed cells with strong proliferation, migration and adhesion ability for tissue engineering.

  5. Potential Role of Dentin Sialoprotein by Inducing Dental Pulp Mesenchymal Stem Cell Differentiation and Mineralization for Dental Tissue Repair

    OpenAIRE

    Yuan, Guo-Hua; Yang, Guo-Bin; Wu, Li-An; Chen, Zhi; Chen, Shuo

    2010-01-01

    Introduction: Dentin sialoprotein (DSP) is a dentin extracellular matrix protein, a unique marker of dentinogenesis and plays a vital role in odontoblast differentiation and dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues dentin deficiency and increases enamel mineralization in animal models.The hypothesis: DSP as a nature therapeutic agent stimu...

  6. A retrospective study on traumatic dental and soft-tissue injuries in preschool children in Zagreb, Croatia.

    Science.gov (United States)

    Vuletić, Marko; Škaričić, Josip; Batinjan, Goran; Trampuš, Zdenko; Čuković Bagić, Ivana; Jurić, Hrvoje

    2014-02-01

    The purpose of this study was to analyze data according to gender, age, cause, number of traumatized teeth, time elapsed before treatment and type of tooth from the records of traumatized children. A retrospective study was conducted in the Department of Paediatric Dentistry at the University Dental Clinic in Zagreb, Croatia using the documentation of 128 patients (61 males and 67 females) aged 1 month to 6 years with injuries of primary teeth between February 2009 and January 2013. Trauma was seen in 217 primary teeth, which implies that the number of injured primary teeth was 1.69 per child. The maxillary central incisors were the most frequently affected teeth (81.1%), they were followed by maxillary lateral incisors, while the least affected were mandibular central incisors. Traumatic dental injuries involved periodontal tissue 2.82 times more frequently than hard dental and pulp tissue. The main cause of teeth injury was fall (67.2%) and the majority of injuries occurred at home (51.6%) (p<0.05). Of 128 patients who received treatment 71 (55.5%) also had soft-tissue injuries. The distribution of soft-tissue injuries by gender (35 males, 36 females) was not statistically significant. Comparing children with soft-tissue injuries and those without them, a statistically significant difference was found in the time of arrival (p<0.01). The results of this study showed the need of informing about preventive measures against falls at home and the methods of providing first aid in dental trauma injuries.

  7. Phenylalanine kinetics in human adipose tissue.

    OpenAIRE

    Coppack, S W; Persson, M; Miles, J M

    1996-01-01

    Very little is known about the regulation of protein metabolism in adipose tissue. In this study systemic, adipose tissue, and forearm phenylalanine kinetics were determined in healthy postabsorptive volunteers before and during a 2-h glucose infusion (7 mg.kg-1.min-1). [3H]Phenylalanine was infused and blood was sampled from a radial artery, a subcutaneous abdominal vein, and a deep forearm vein. Adipose tissue and forearm blood flow were measured with 133Xe and plethysmography, respectively...

  8. Knowledge about Human Papillomavirus and Cervical Cancer: Predictors of HPV Vaccination among Dental Students

    Science.gov (United States)

    Rajiah, Kingston; Maharajan, Mari Kannan; Fang Num, Kelly Sze; How Koh, Raymond Chee

    2017-06-25

    Background: The objective of this study is to determine the influence of dental students’ knowledge and attitude regarding human papillomavirus infection of cervical cancer on willingness to pay for vaccination. Basic research design: A convenience sampling method was used. The minimal sample size of 136 was calculated using the Raosoft calculator with a 5 % margin of error and 95% confidence level. Participants: The study population were all final year dental students from the School of Dentistry. Methods: A self-administered questionnaire was used to measure knowledge levels and attitudes regarding human papillomavirus vaccination. Contingent valuation was conducted for willingness to pay for vaccination. Main outcome measures: The Center for Disease Control and Prevention has stated that human papillomavirus are associated with oropharynx cancer and the American Dental Association insist on expanding public awareness of the oncogenic potential of some HPV infections. Thus, as future dental practitioners, dental students should be aware of human papillomavirus and their links with cancer and the benefits of vaccination. Results: Knowledge on HPV and cervical cancer did not impact on attitudes towards vaccines. However, significant correlation existed between knowledge and willingness to pay for vaccination. Conclusions: Dental students’ knowledge on HPV and cervical cancer has no influence on their attitude towards HPV vaccines. However, their willingness to pay for HPV vaccination is influenced by their knowledge of cervical cancer and HPV vaccination. Creative Commons Attribution License

  9. [Three dimensional bioprinting technology of human dental pulp cells mixtures].

    Science.gov (United States)

    Xue, Shi-hua; Lv, Pei-jun; Wang, Yong; Zhao, Yu; Zhang, Ting

    2013-02-18

    To explore the three dimensional(3D)bioprinting technology, using human dental pulp cells (hDPCs) mixture as bioink and to lay initial foundations for the application of the 3D bioprinting technology in tooth regeneration. Imageware 11.0 computer software was used to aid the design of the 3D biological printing blueprint. Sodium alginate-gelatin hydrosol was prepared and mixed with in vitro isolated hDPCs. The mixture contained 20 g/L sodium alginate and 80 g/L gelatin with cell density of 1×10(6)/mL. The bioprinting of hDPCs mixture was carried out according to certain parameters; the 3D constructs obtained by printing were examined; the viability of hDPCs after printing by staining the constructs with calcein-AM and propidium iodide dye and scanning of laser scanning confocal microscope was evaluated. The in vitro constructs obtained by the bioprinting were cultured, and the proliferation of hDPCs in the constructs detected. By using Imageware 11.0 software, the 3D constructs with the grid structure composed of the accumulation of staggered cylindrical microfilament layers were obtained. According to certain parameters, the hDPCs-sodium alginate-gelatin blends were printed by the 3D bioprinting technology. The self-defined shape and dimension of 3D constructs with the cell survival rate of 87%± 2% were constructed. The hDPCs could proliferate in 3D constructs after printing. In this study, the 3D bioprinting of hDPCs mixtures was realized, thus laying initial foundations for the application of the 3D bioprinting technology in tooth regeneration.

  10. A Novel Strategy to Engineer Pre-Vascularized Full-Length Dental Pulp-like Tissue Constructs.

    Science.gov (United States)

    Athirasala, Avathamsa; Lins, Fernanda; Tahayeri, Anthony; Hinds, Monica; Smith, Anthony J; Sedgley, Christine; Ferracane, Jack; Bertassoni, Luiz E

    2017-06-12

    The requirement for immediate vascularization of engineered dental pulp poses a major hurdle towards successful implementation of pulp regeneration as an effective therapeutic strategy for root canal therapy, especially in adult teeth. Here, we demonstrate a novel strategy to engineer pre-vascularized, cell-laden hydrogel pulp-like tissue constructs in full-length root canals for dental pulp regeneration. We utilized gelatin methacryloyl (GelMA) hydrogels with tunable physical and mechanical properties to determine the microenvironmental conditions (microstructure, degradation, swelling and elastic modulus) that enhanced viability, spreading and proliferation of encapsulated odontoblast-like cells (OD21), and the formation of endothelial monolayers by endothelial colony forming cells (ECFCs). GelMA hydrogels with higher polymer concentration (15% w/v) and stiffness enhanced OD21 cell viability, spreading and proliferation, as well as endothelial cell spreading and monolayer formation. We then fabricated pre-vascularized, full-length, dental pulp-like tissue constructs by dispensing OD21 cell-laden GelMA hydrogel prepolymer in root canals of extracted teeth and fabricating 500 µm channels throughout the root canals. ECFCs seeded into the microchannels successfully formed monolayers and underwent angiogenic sprouting within 7 days in culture. In summary, the proposed approach is a simple and effective strategy for engineering of pre-vascularized dental pulp constructs offering potentially beneficial translational outcomes.

  11. A High-Resolution Proteomic Landscaping of Primary Human Dental Stem Cells: Identification of SHED- and PDLSC-Specific Biomarkers

    Directory of Open Access Journals (Sweden)

    Vasiliki Taraslia

    2018-01-01

    Full Text Available Dental stem cells (DSCs have emerged as a promising tool for basic research and clinical practice. A variety of adult stem cell (ASC populations can be isolated from different areas within the dental tissue, which, due to their cellular and molecular characteristics, could give rise to different outcomes when used in potential applications. In this study, we performed a high-throughput molecular comparison of two primary human adult dental stem cell (hADSC sub-populations: Stem Cells from Human Exfoliated Deciduous Teeth (SHEDs and Periodontal Ligament Stem Cells (PDLSCs. A detailed proteomic mapping of SHEDs and PDLSCs, via employment of nano-LC tandem-mass spectrometry (MS/MS revealed 2032 identified proteins in SHEDs and 3235 in PDLSCs. In total, 1516 proteins were expressed in both populations, while 517 were unique for SHEDs and 1721 were exclusively expressed in PDLSCs. Further analysis of the recorded proteins suggested that SHEDs predominantly expressed molecules that are involved in organizing the cytoskeletal network, cellular migration and adhesion, whereas PDLSCs are highly energy-producing cells, vastly expressing proteins that are implicated in various aspects of cell metabolism and proliferation. Applying the Rho-GDI signaling pathway as a paradigm, we propose potential biomarkers for SHEDs and for PDLSCs, reflecting their unique features, properties and engaged molecular pathways.

  12. Human dental pulp stem cells and gingival fibroblasts seeded into silk fibroin scaffolds have the same ability in attracting vessels

    Directory of Open Access Journals (Sweden)

    Anna eWoloszyk

    2016-04-01

    Full Text Available Neovascularization is one of the most important processes during tissue repair and regeneration. Current healing approaches based on the use of biomaterials combined with stem cells in critical-size bone defects fail due to the insufficient implant vascularization and integration into the host tissues. Therefore, here we studied the attraction, ingrowth, and distribution of blood vessels from the chicken embryo chorioallantoic membrane into implanted silk fibroin scaffolds seeded with either human dental pulp stem cells or human gingival fibroblasts. Perfusion capacity was evaluated by non-invasive in vivo Magnetic Resonance Imaging while the number and density of blood vessels were measured by histomorphometry. Our results demonstrate that human dental pulp stem cells and gingival fibroblasts possess equal abilities in attracting vessels within silk fibroin scaffolds. Additionally, the prolonged in vitro pre-incubation period of these two cell populations favors the homogeneous distribution of vessels within silk fibroin scaffolds, which further improves implant survival and guarantees successful healing and regeneration.

  13. The use of animal tissues alongside human tissue: Cultural and ethical considerations.

    Science.gov (United States)

    Kaw, Anu; Jones, D Gareth; Zhang, Ming

    2016-01-01

    Teaching and research facilities often use cadaveric material alongside animal tissues, although there appear to be differences in the way we handle, treat, and dispose of human cadaveric material compared to animal tissue. This study sought to analyze cultural and ethical considerations and provides policy recommendations on the use of animal tissues alongside human tissue. The status of human and animal remains and the respect because of human and animal tissues were compared and analyzed from ethical, legal, and cultural perspectives. The use of animal organs and tissues is carried out within the context of understanding human anatomy and function. Consequently, the interests of human donors are to be pre-eminent in any policies that are enunciated, so that if any donors find the presence of animal remains unacceptable, the latter should not be employed. The major differences appear to lie in differences in our perceptions of their respective intrinsic and instrumental values. Animals are considered to have lesser intrinsic value and greater instrumental value than humans. These differences stem from the role played by culture and ethical considerations, and are manifested in the resulting legal frameworks. In light of this discussion, six policy recommendations are proposed, encompassing the nature of consent, respect for animal tissues as well as human remains, and appropriate separation of both sets of tissues in preparation and display. © 2015 Wiley Periodicals, Inc.

  14. A Miniature Swine Model for Stem Cell-Based De Novo Regeneration of Dental Pulp and Dentin-Like Tissue.

    Science.gov (United States)

    Zhu, Xiaofei; Liu, Jie; Yu, Zongdong; Chen, Chao-An; Aksel, Hacer; Azim, Adham A; Huang, George T-J

    2018-02-01

    The goal of this study was to establish mini-swine as a large animal model for stem cell-based pulp regeneration studies. Swine dental pulp stem cells (sDPSCs) were isolated from mini-swine and characterized in vitro. For in vivo studies, we first employed both ectopic and semi-orthotopic study models using severe combined immunodeficiency mice. One is hydroxyapatite-tricalcium phosphate (HA/TCP) model for pulp-dentin complex formation, and the other is tooth fragment model for complete pulp regeneration with new dentin depositing along the canal walls. We found that sDPSCs are similar to their human counterparts exhibiting mesenchymal stem cell characteristics with ability to form colony forming unit-fibroblastic and odontogenic differentiation potential. sDPSCs formed pulp-dentin complex in the HA/TCP model and showed pulp regeneration capacity in the tooth fragment model. We then tested orthotopic pulp regeneration on mini-swine including the use of multi-rooted teeth. Using autologous sDPSCs carried by hydrogel and transplanted into the mini-swine root canal space, we observed regeneration of vascularized pulp-like tissue with a layer of newly deposited dentin-like (rD) tissue or osteodentin along the canal walls. In some cases, dentin bridge-like structure was observed. Immunohistochemical analysis detected the expression of nestin, dentin sialophosphoprotein, dentin matrix protein 1, and bone sialoprotein in odontoblast-like cells lining against the produced rD. We also tested the use of allogeneic sDPSCs for the same procedures. Similar findings were observed in allogeneic transplantation. This study is the first to show an establishment of mini-swine as a suitable large animal model utilizing multi-rooted teeth for further cell-based pulp regeneration studies.

  15. Detection of Sulphate-Reducing Bacteria and Others Cultivable Facultative Bacteria in Dental Tissues

    Directory of Open Access Journals (Sweden)

    Lúcio de Souza Gonçalves

    2014-01-01

    Full Text Available Aim: To detect for the presence of sulphate-reducing bacteria (SRB and evaluate the possible association between SRB and cultivable facultative bacterial of oral sites with different periodontal conditions. Methods: The study was carried out on 9 samples from different oral sites in 8 patients (two samples were collected from the same patient. Material was collected using modified Postgate E culture medium, indicated for the growth and isolation of SRB. In addition, a reducing solution for anaerobic bacteria was used as a transport solution for facultative bacteria and identified by polymerase chain reaction amplification (PCR and sequencing of the 16S rRNA gene. Results: SRB was found in 3 patient samples: the first in a root fragment, the second in a root fragment and a healthy tooth with vertical bone loss and a mobility degree of 3; and the third in a healthy tooth extracted for orthodontic treatment. In the final patient, the cultivable facultative species Lactobacillus casei was identified. Other facultative bacterial species were identified in patient 5 (Kurthia Gibsonii and patient 7 (Pseudomonas aeruginosa. Conclusions: The detection of SRB in different dental tissues with distinct periodontal features demonstrated that new studies need to be developed in order to determine the true role of SRB in the oral microbiota. In addition, it was possible to verify the presence of Lactobacillus casei together with SRB in one sample.

  16. N-Acetyl Cysteine Depletes Reactive Oxygen Species and Prevents Dental Monomer-Induced Intrinsic Mitochondrial Apoptosis In Vitro in Human Dental Pulp Cells.

    Directory of Open Access Journals (Sweden)

    Yang Jiao

    Full Text Available To investigate the involvement of intrinsic mitochondrial apoptosis in dental monomer-induced cytotoxicity and the influences of N-acetyl cysteine (NAC on this process.Human dental pulp cells (hDPCs were exposed to several dental monomers in the absence or presence of NAC, and cell viability, intracellular redox balance, morphology and function of mitochondria and key indicators of intrinsic mitochondrial apoptosis were evaluated using various commercial kits.Dental monomers exerted dose-dependent cytotoxic effects on hDPCs. Concomitant to the over-production of reactive oxygen species (ROS and depletion of glutathione (GSH, differential changes in activities of superoxide dismutase, glutathione peroxidase, and catalase were detected. Apoptosis, as indicated by positive Annexin V/propidium iodide (PI staining and activation of caspase-3, was observed after dental monomer treatment. Dental monomers impaired the morphology and function of mitochondria, and induced intrinsic mitochondrial apoptosis in hDPCs via up-regulation of p53, Bax and cleaved caspase-3, and down-regulation of Bcl-2. NAC restored cell viability, relieved oxidative stress and blocked the apoptotic effects of dental monomers.Dental monomers induced oxidative stress and mitochondrial intrinsic apoptosis in hDPCs. NAC could reduce the oxidative stress and thus protect hDPCs against dental monomer-induced apoptosis.

  17. Interaction of slow highly charged ions with hard dental tissue: studies of fluoride uptake and reminalization efficacy

    International Nuclear Information System (INIS)

    Daskalova, A; Kasperski, G; Rousseau, P; Domaracka, A; Lawicki, A

    2014-01-01

    TOF-SIMS mass spectroscopy data are presented on ion irradiation of hard dental tissue using a beam of 129 Xe 20+ (15 kV) ions delivered in the ARIBE facility by an ECR source. The investigation was focused on the mass distribution of the fragment ions. A comparison is made between the mass spectra from hard dental tissue treated by olaflur-(C 27 H 60 F 2 N 2 O 3 ) and untreated hard dental tissue obtained under irradiation by low-energy highly-charged ions (HCIs). We found significant differences between the mass spectra of enamel after introducing amine fluoride (olaflur) and the mass spectra of pure untreated enamel. Further, we separated out the effects caused by radiation induced in the tooth enamel from those induced in dentin, which has not been performed before. In order to conduct a further detailed analysis, it is necessary to extend the research scope to include the influence of fluorine compounds on enamel and dentin.

  18. Dental OCT

    Science.gov (United States)

    Wilder-Smith, Petra; Otis, Linda; Zhang, Jun; Chen, Zhongping

    This chapter describes the applications of OCT for imaging in vivo dental and oral tissue. The oral cavity is a diverse environment that includes oral mucosa, gingival tissues, teeth and their supporting structures. Because OCT can image both hard and soft tissues of the oral cavity at high resolution, it offers the unique capacity to identity dental disease before destructive changes have progressed. OCT images depict clinically important anatomical features such as the location of soft tissue attachments, morphological changes in gingival tissue, tooth decay, enamel thickness and decay, as well as the structural integrity of dental restorations. OCT imaging allows for earlier intervention than is possible with current diagnostic modalities.

  19. Site specific mineral composition and microstructure of human supra-gingival dental calculus.

    Science.gov (United States)

    Hayashizaki, Junko; Ban, Seiji; Nakagaki, Haruo; Okumura, Akihiko; Yoshii, Saori; Robinson, Colin

    2008-02-01

    Dental calculus has been implicated in the aetiology of several periodontal conditions. Its prevention and removal are therefore desirable clinical goals. While it is known that calculus is very variable in chemical composition, crystallinity and crystallite size little is known about site specific variability within a dentition and between individuals. With this in mind, a study was undertaken to investigate the comparative site specific nature and composition of human dental supra-gingival dental calculus obtained from 66 male patients visiting for their dental check-up using fluorescent X-ray spectroscopy, X-ray diffractometry and Fourier transform infrared spectroscopy. The supra-gingival dental calculus formed on the lingual surfaces of lower anterior teeth and the buccal surfaces of upper molar teeth were classified into four types based on calcium phosphate phases present. There was significant difference in composition of the crystal phase types between lower and upper teeth (pdental calculus on anterior or molar teeth of all samples. The degree of crystallinity of dental calculus formed on the upper molar teeth was higher than that formed on the lower anterior teeth (pdental calculus formed on the lower anterior teeth were higher than on upper molar teeth (pdental supra-gingival dental calculus is related to its location in the mouth.

  20. The Role of Nephronectin on Proliferation and Differentiation in Human Dental Pulp Stem Cells

    Directory of Open Access Journals (Sweden)

    Jia Tang

    2017-01-01

    Full Text Available Aim. The purpose of the current study was to investigate the effects of nephronectin (Npnt in human dental pulp stem cells (hDPSCs. Methodology. Npnt was coated to nontissue culture-treated polystyrene (non-PS plates. The presence of immobilized protein on the surface was detected by polyclonal rabbit primary anti-Npnt antibody. Then the cell number was counted and compared with PBS-, bovine serum albumin- (BSA-, fish scale type I collagen- (FCOL1-, and human fibronectin- (Fn- coated wells. Cell proliferation was assessed using CCK-8 assay. Cell morphology was observed under light microscopy and fluorescence microscopy. Lastly, the mRNA expression profiles of integrins, dentin sialophosphoprotein (DSPP, bone sialoprotein (BSP, and mineralization capacity of hDPSCs were investigated by real time RT-PCR and alizarin red staining, respectively. Results. Npnt mediates hDPSC adhesion and spreading partially via the Arg-Gly-Asp (RGD motif. Npnt enhanced the mRNA expression of ITGA1, ITGA4, ITGA7, and ITGB1 on day five. Npnt downregulated DSPP but significantly upregulated BSP mRNA expression at day 28. Further, Npnt and FCOL1 accelerated the matrix mineralization in hDPSCs. Conclusions. The current findings implicate that Npnt would be favorable to recruit hDPSCs and conducive to mineralization in hDPSCs. The combination of Npnt with hDPSCs may offer a promising approach for hard tissue regeneration.

  1. Investigation of functional activity human dental pulp stem cells at acute and chronic pulpitis.

    Science.gov (United States)

    Ustiashvili, M; Kordzaia, D; Mamaladze, M; Jangavadze, M; Sanodze, L

    2014-09-01

    It is already recognized that together with the other connective tissues organ-specific progenic stem cells are also found in postnatal dental pulp. This group of undifferentiated cells is only 1% of total cell population of the pulp. The aim of the study was the identification of stem cells in human dental pulp, detection of their localization and assessment of functional activity during inflammation process and/or at norm. The obtained results showed that at acute pulpitis the pulp stroma is hypocellular in comparison with the norm but cells proliferative activity is low. CD 133 and NCAM (CD 56) positive stem cells were found in perivascularl space of the pulp stroma and in Hohle layer. At process prolongation and transition to the chronic phase pulp stroma is hypercellular, the cells with large, rounded or oval-shaped nuclei with clear chromatin appear together with fibroblasts. They are distributed as about entire thickness of the stroma as especially Hohle layer. In such cells higher proliferative activity (Ki67 expression) was observed. The cells in the mentioned proliferation phase are intensively marked by CD133, the rate of which is high in Hohle layer and along it. A large number of NCAM (CD 56) positive cells appear in pulp stroma. During pulpitis an involvement of stem cells into the process of reparative dentinogenesis should be conducted stepwise. In acute cases of the disease, stem cell perivascularl mobilization and proliferation and its migration to Hohle layer occur in response to irritation /stimulation. Chronification of the process leads not only to the migration of stem cells to the periphery of the pulp but also s their В«maturationВ» (increase of NCAM expression in the stem cells), which causes an increase the number of dentin producing active odontoblasts and initiation of reparative dentinogenesis.

  2. Overexpression of Receptor for Advanced Glycation End Products and High-Mobility Group Box 1 in Human Dental Pulp Inflammation

    Directory of Open Access Journals (Sweden)

    Salunya Tancharoen

    2014-01-01

    Full Text Available High mobility group box 1 (HMGB1, a nonhistone DNA-binding protein, is released into the extracellular space and promotes inflammation. HMGB1 binds to related cell signaling transduction receptors, including receptor for advanced glycation end products (RAGE, which actively participate in vascular and inflammatory diseases. The aim of this study was to examine whether RAGE and HMGB1 are involved in the pathogenesis of pulpitis and investigate the effect of Prevotella intermedia (P. intermedia lipopolysaccharide (LPS on RAGE and HMGB1 expression in odontoblast-like cells (OLC-1. RAGE and HMGB1 expression levels in clinically inflamed dental pulp were higher than those in healthy dental pulp. Upregulated expression of RAGE was observed in odontoblasts, stromal pulp fibroblasts-like cells, and endothelial-like cell lining human pulpitis tissue. Strong cytoplasmic HMGB1 immunoreactivity was noted in odontoblasts, whereas nuclear HMGB1 immunoreactivity was seen in stromal pulp fibroblasts-like cells in human pulpitis tissue. LPS stimulated OLC-1 cells produced HMGB1 in a dose-dependent manner through RAGE. HMGB1 translocation towards the cytoplasm and secretion from OLC-1 in response to LPS was inhibited by TPCA-1, an inhibitor of NF-κB activation. These findings suggest that RAGE and HMGB1 play an important role in the pulpal immune response to oral bacterial infection.

  3. Modulation of human dermal microvascular endothelial cell and human gingival fibroblast behavior by micropatterned silica coating surfaces for zirconia dental implant applications

    International Nuclear Information System (INIS)

    Laranjeira, Marta S; Carvalho, Ângela; Ferraz, Maria Pia; Monteiro, Fernando Jorge; Pelaez-Vargas, Alejandro; Hansford, Derek; Coimbra, Susana; Costa, Elísio; Santos-Silva, Alice; Fernandes, Maria Helena

    2014-01-01

    Dental ceramic implants have shown superior esthetic behavior and the absence of induced allergic disorders when compared to titanium implants. Zirconia may become a potential candidate to be used as an alternative to titanium dental implants if surface modifications are introduced. In this work, bioactive micropatterned silica coatings were produced on zirconia substrates, using a combined methodology of sol–gel processing and soft lithography. The aim of the work was to compare the in vitro behavior of human gingival fibroblasts (HGFs) and human dermal microvascular endothelial cells (HDMECs) on three types of silica-coated zirconia surfaces: flat and micropatterned (with pillars and with parallel grooves). Our results showed that cells had a higher metabolic activity (HGF, HDMEC) and increased gene expression levels of fibroblast-specific protein-1 (FSP-1) and collagen type I (COL I) on surfaces with pillars. Nevertheless, parallel grooved surfaces were able to guide cell growth. Even capillary tube-like networks of HDMEC were oriented according to the surface geometry. Zirconia and silica with different topographies have shown to be blood compatible and silica coating reduced bacteria adhesion. All together, the results indicated that microstructured bioactive coating seems to be an efficient strategy to improve soft tissue integration on zirconia implants, protecting implants from peri-implant inflammation and improving long-term implant stabilization. This new approach of micropatterned silica coating on zirconia substrates can generate promising novel dental implants, with surfaces that provide physical cues to guide cells and enhance their behavior. (paper)

  4. Human normal tissue reactions in radiotherapy

    International Nuclear Information System (INIS)

    Taniike, Keiko

    1990-01-01

    Acute and late normal tissue reactions in radiotherapy have not been considered to be major problems with conventional fractionation. But they may cause certain problems when newer schedules such as hyperfractionation or accelerated fractionation are used. In opposing parallel radiotherapy, the dose fractionation of skin or subcutaneous connective tissue are different between in one portal and two portals daily. So we examined acute skin erythema and late connective tissue fibrosis in the two groups (one and two portals) of the patients with uterus cancer. Acute skin erythema and late connective tissue fibrosis were slightly stronger in case of one portal daily. In relation to the anatomical site of skin, acute skin erythema was stronger at the buttocks than the lower abdomen, but late fibrosis was reverse to that. So the degree of acute skin erythema did not predict the degree of late connective tissue fibrosis. The number of Time Dose Fractionation Factor could roughly estimate the degree of erythema and fibrosis. Late fibrosis in 36 fractions increased with an increase of abdominal thickness, but acute erythema did not. (author)

  5. Estimation and quantification of human DNA in dental calculus: A pilot study.

    Science.gov (United States)

    Singh, Udita; Goel, Saurabh

    2017-01-01

    Identification using DNA has proved its accuracy multiple times in the field of forensic investigations. Investigators usually rely on either teeth or bone as the DNA reservoirs. However, there are instances where the skeletal or dental remains are not available or not preserved properly. Moreover, due to religious beliefs, the family members of the dead do not allow the investigating team to damage the remains for the sole purpose of identification. To investigate the presence of human DNA in dental calculus and to quantify the amount, if present. This prospective single-blinded pilot study included twenty subjects selected from the patients visiting a dental college. The samples of dental calculus were collected from the thickest portion of calculus deposited on the lingual surfaces of mandibular incisors. These samples were decontaminated and subjected to gel electrophoresis for DNA extraction. DNA was found in 85% cases. The amount of DNA varied from 21 to 37 μg/ml of dental calculus. Dental calculus is a rich reservoir of human DNA.

  6. Comparative characterization of stem cells from human exfoliated deciduous teeth, dental pulp, and bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Kunimatsu, Ryo; Nakajima, Kengo; Awada, Tetsuya; Tsuka, Yuji; Abe, Takaharu; Ando, Kazuyo; Hiraki, Tomoka; Kimura, Aya; Tanimoto, Kotaro

    2018-06-18

    Mesenchymal stem cells (MSCs) are used clinically in tissue engineering and regenerative medicine. The proliferation and osteogenic differentiation potential of MSCs vary according to factors such as tissue source and cell population heterogeneity. Dental tissue has received attention as an easily accessible source of high-quality stem cells. In this study, we compared the in vitro characteristics of dental pulp stem cells from deciduous teeth (SHED), human dental pulp stem cells (hDPSCs), and human bone marrow mesenchymal stem cells (hBMSCs). SEHD and hDPSCs were isolated from dental pulp and analyzed in comparison with human bone marrow (hBM)MSCs. Proliferative capacity of cultured cells was analyzed using a bromodeoxyuridine immunoassay and cell counting. Alkaline phosphatase (ALP) levels were monitored to assess osteogenic differentiation. Mineralization was evaluated by alizarin red staining. Levels of bone marker mRNA were examined by real-time PCR analysis. SHED were highly proliferative compared with hDPSCs and hBMSCs. SHED, hDPSCs, and hBMSCs exhibited dark alizarin red staining on day 21 after induction of osteogenic differentiation, and staining of hBMSCs was significantly higher than that of SHED and hDPSCs by spectrophotometry. ALP staining was stronger in hBMSCs compared with SHED and hDPSCs, and ALP activity was significantly higher in hBMSCs compared with SHED or hDPSCs. SHED showed significantly higher expression of the Runx2 and ALP genes compared with hBMSCs, based on real-time PCR analysis. In bFGF, SHED showed significantly higher expression of the basic fibroblast growth factor (bFGF) gene compared with hDPSCs and hBMSCs. SHED exhibited higher proliferative activity and levels of bFGF and BMP-2 gene expression compared with BMMSCs and DPSCs. The ease of harvesting cells and ability to avoid invasive surgical procedures suggest that SHED may be a useful cell source for application in bone regeneration treatments. Copyright © 2018 Elsevier Inc

  7. Engineering Human Neural Tissue by 3D Bioprinting.

    Science.gov (United States)

    Gu, Qi; Tomaskovic-Crook, Eva; Wallace, Gordon G; Crook, Jeremy M

    2018-01-01

    Bioprinting provides an opportunity to produce three-dimensional (3D) tissues for biomedical research and translational drug discovery, toxicology, and tissue replacement. Here we describe a method for fabricating human neural tissue by 3D printing human neural stem cells with a bioink, and subsequent gelation of the bioink for cell encapsulation, support, and differentiation to functional neurons and supporting neuroglia. The bioink uniquely comprises the polysaccharides alginate, water-soluble carboxymethyl-chitosan, and agarose. Importantly, the method could be adapted to fabricate neural and nonneural tissues from other cell types, with the potential to be applied for both research and clinical product development.

  8. Tissue Engineering of Necrotic Dental Pulp of Immature Teeth with Apical Periodontitis in Dogs: Radiographic and Histological Evaluation.

    Science.gov (United States)

    El Ashiry, Eman A; Alamoudi, Najlaa M; El Ashiry, Mahmoud K; Bastawy, Hagar A; El Derwi, Douaa A; Atta, Hazem M

    2018-05-15

    To evaluate tissue engineering technology to regenerate pulp-dentin like tissues in pulp canals of immature necrotic permanent teeth with apical periodontitis in dogs. The study was performed on 36 teeth in 12 dogs. The experiment was carried out using split mouth design. In each dog 3 teeth were selected for implementing the study procedure. Apical periodontitis was induced in Group A and B teeth. Group (A): immature upper left 2 nd permanent incisors that were transplanted with a construct of autologous dental pulp stem cells with growth factors seeded in a chitosn hydrogel scaffold. Group (B): immature upper right 2 nd permanent incisor that received only growth factors with scaffold. A third tooth in each dog was selected randomly for isolation of dental pulp stem cells (DPSCs). Both groups were closed with a double coronal seal of white MTA (Mineral trioxide aggregate) and glass ionomer cement. Both groups were monitored radiographically for 4 months and histologically after sacrificing the animals. There was no statistically significant difference in radiographic findings between group (A) and group (B) for healing of radiolucencies, while there was statistically significant difference between group (A) and group (B) regarding radicular thickening, root lengthening and apical closure. Histologically, group (A) teeth showed regeneration of pulp-dentin like tissue while group (B) teeth did not show any tissue regeneration. Dental pulp stem cells and growth factors incorporated in chitosan hydrogel are able to regenerate pulp-dentine like tissue and help in complete root maturation of non-vital immature permanent teeth with apical periodontitis in dogs.

  9. [Lasers in dentistry. Part B--Interaction with biological tissues and the effect on the soft tissues of the oral cavity, the hard tissues of the tooth and the dental pulp].

    Science.gov (United States)

    Moshonov, J; Stabholz, A; Leopold, Y; Rosenberg, I; Stabholz, A

    2001-10-01

    The interaction of laser energy with target tissue is mainly determined by two non operator-dependent factors: the specific wavelength of the laser and the optical properties of the target tissues. Power density, energy density, pulse repetition rate, pulse duration and the mode of energy transferring to the tissue are dictated by the clinician. Combination of these factors enables to control optimal response for the clinical application. Four responses are described when the laser beam hits the target tissue: reflection, absorption, transmission and scattering. Three main mechanisms of interaction between the laser and the biological tissues exist: photothermic, photoacoustic and photochemical. The effect of lasers on the soft tissues of the oral cavity is based on transformation of light energy into thermal energy which, in turn heats the target tissue to produce the desirable effect. In comparison to the scalpel used in surgical procedures, the laser beam is characterized by tissue natural sterility and by minimum bleeding during the surgical procedures due to blood vessels welding. The various effects achieved by the temperature elevation during the laser application on the soft tissue are: I. coagulation and hemostasis II. tissue sterilization III. tissue welding IV. incision and excision V. ablation and vaporization Ablation and melting are the two basic modalities by which the effect of lasers on the hard tissues of the tooth is produced. When discussing the effect of laser on dental hard tissues, the energy absorption in the hydroxyapatite plays a major role in addition to its absorption in water. When laser energy is absorbed in the water of the hard tissues, a rapid volume expansion of the evaporating water occurs as a result of a substantial temperature elevation in the interaction site. Microexplosions are produced causing hard tissue disintegration. If pulp temperatures are raised beyond 5 degrees C level, damage to the dental pulp is irreversible

  10. Identification of human tissue cross-presenting dendritic cells

    OpenAIRE

    Haniffa, Muzlifah; Collin, Matthew; Ginhoux, Florent

    2013-01-01

    Dendritic cells (DCs) are a heterogeneous group of functionally specialized antigen-presenting cells. We recently characterized the human tissue cross-presenting DCs and aligned the human and mouse DC subsets. Our findings will facilitate the translation of murine DC studies to the human setting and aid the design of DC-based vaccine strategies for infection and cancer immunotherapy.

  11. Chapter 8. Ionisation radiation and human organism. Radioactivity of human tissues

    International Nuclear Information System (INIS)

    Toelgyessy, J.; Harangozo, M.

    2000-01-01

    This is a chapter of textbook of radioecology for university students. In this chapter authors deal with ionisation radiation and human organism as well as with radioactivity of human tissues. Chapter consists of next parts: (1) Radiation stress of human organism; (2) Radioactivity of human tissues and the factors influencing radioactive contamination; (3) Possibilities of decreasing of radiation stress

  12. Preliminary Examination of X-ray Scattering from Human Tissues

    International Nuclear Information System (INIS)

    Desouky, O.S.; Wilkinson, S.; Hall, C.; Rogers, K.; Round, A.

    2008-01-01

    Small Angle x-ray scattering (SAXS) and wide angle x-ray scattering (WAXS) patterns have been recorded from different human soft tissues using x-ray synchrotron radiation.Pathological breast, normal kidney and lung tissues show SAXS peaks at q-values equal to 0.291 nm -1 and 0.481 nm -1 (d 21.6 nm and d =13. nm) which are the 3 r d and 5 t h order of the well known axial D-spacing of collagen fibrils. The diffraction is particularly intense in the meridional direction indicating some febrile alignment. In contrast, the normal tissue of brain, liver and heart shows diffuse scatter.The wide-angle coherent scattering from normal human tissues of brain, liver, heart, lung, and kidney is typical of that for amorphous materials. The scatter of the healthy adipose breast tissue shows a sharp peak at momentum transfer 1.24 nm -1 (d= 0.417 nm). The data of the other tissues appears to consist of a broad scattering peak. The two scattering regimes succeed in differentiating between the two major components of breast tissue, collagen and adipose tissue. The results of this study suggest that the soft tissues may have scattering patterns that are characteristics for the particular tissue types and tissue disease state. These results indicate that it may be possible use the coherent scattering as a diagnostic tool

  13. Global Dental Research Productivity and Its Association With Human Development, Gross National Income, and Political Stability.

    Science.gov (United States)

    Allareddy, Veerasathpurush; Allareddy, Veeratrishul; Rampa, Sankeerth; Nalliah, Romesh P; Elangovan, Satheesh

    2015-09-01

    The objective of this study is to examine the associations between country level factors (such as human development, economic productivity, and political stability) and their dental research productivity. This study is a cross-sectional analysis of bibliometric data from Scopus search engine. Human Development Index (HDI), Gross National Income per capita (GNI), and Failed State Index measures were the independent variables. Outcomes were "Total number of publications (articles or articles in press) in the field of dentistry" and "Total number of publications in the field of dentistry per million population." Non-parametric tests were used to examine the association between the independent and outcome variables. During the year 2013, a total of 11,952 dental research articles were published across the world. The top 5 publishing countries were United States, Brazil, India, Japan, and United Kingdom. "Very High" HDI countries had significantly higher number of total dental research articles and dental research articles per million population when compared to the "High HDI," "Medium HDI," and "Low HDI" countries (p < 0.0001). There was a significant linear relationship between the GNI quartile income levels and outcome metrics (p ≤ 0.007). Countries which were highly politically stable were associated with significantly higher dental research productivity (p < 0.0001). There appears to be a regional concentration of articles with just five countries contributing to over 50% of all articles. The human development and economic development of a country are linearly correlated with dental research productivity. Dental research productivity also increases with increasing political stability of a country. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Evidence for xylitol 5-P production in human dental plaque

    Energy Technology Data Exchange (ETDEWEB)

    Waaler, S.M. (Department of Preclinical Techniques and Material Sciences and Department of Pedodontics, Dental Faculty, University of Oslo, Oslo (Norway))

    1992-01-01

    The Turku sugar studies indicated that xylitol may possess a caries-therapeutic effect. More recent data show that xylotol exhibits a bacteriostatic activity on a wide range of bacteria based on uptake and expulsion of xylitol. Intracellular xylitol 5-P appears to be a key substance associated with inhibition of bacterial metabolism by xylitol. This has been shown in studies with pure strains of bacteria, mainly Streptococcus mutans. The aim of the present study was to examine if production of xylitol 5-P occurs in freshly collected dental plaque which is exposed to labeled xylitol. Plaque extracts were analyzed by thin-layer chromatography combined with autoradiography and high performance liquid chromatography. Strong indications were obtained that xylitol 5-P is readily produced by dental plaque. No other significant xylitol metabolites were identified. The bacteriostatic properties of xylitol in plaque are a mechanism which may well account for the caries-therapeutic effect of xylitol. (au).

  15. Evidence for xylitol 5-P production in human dental plaque

    International Nuclear Information System (INIS)

    Waaler, S.M.

    1992-01-01

    The Turku sugar studies indicated that xylitol may possess a caries-therapeutic effect. More recent data show that xylotol exhibits a bacteriostatic activity on a wide range of bacteria based on uptake and expulsion of xylitol. Intracellular xylitol 5-P appears to be a key substance associated with inhibition of bacterial metabolism by xylitol. This has been shown in studies with pure strains of bacteria, mainly Streptococcus mutans. The aim of the present study was to examine if production of xylitol 5-P occurs in freshly collected dental plaque which is exposed to labeled xylitol. Plaque extracts were analyzed by thin-layer chromatography combined with autoradiography and high performance liquid chromatography. Strong indications were obtained that xylitol 5-P is readily produced by dental plaque. No other significant xylitol metabolites were identified. The bacteriostatic properties of xylitol in plaque are a mechanism which may well account for the caries-therapeutic effect of xylitol. (au)

  16. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    Science.gov (United States)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  17. Human tissue models in cancer research: looking beyond the mouse.

    Science.gov (United States)

    Jackson, Samuel J; Thomas, Gareth J

    2017-08-01

    Mouse models, including patient-derived xenograft mice, are widely used to address questions in cancer research. However, there are documented flaws in these models that can result in the misrepresentation of human tumour biology and limit the suitability of the model for translational research. A coordinated effort to promote the more widespread development and use of 'non-animal human tissue' models could provide a clinically relevant platform for many cancer studies, maximising the opportunities presented by human tissue resources such as biobanks. A number of key factors limit the wide adoption of non-animal human tissue models in cancer research, including deficiencies in the infrastructure and the technical tools required to collect, transport, store and maintain human tissue for lab use. Another obstacle is the long-standing cultural reliance on animal models, which can make researchers resistant to change, often because of concerns about historical data compatibility and losing ground in a competitive environment while new approaches are embedded in lab practice. There are a wide range of initiatives that aim to address these issues by facilitating data sharing and promoting collaborations between organisations and researchers who work with human tissue. The importance of coordinating biobanks and introducing quality standards is gaining momentum. There is an exciting opportunity to transform cancer drug discovery by optimising the use of human tissue and reducing the reliance on potentially less predictive animal models. © 2017. Published by The Company of Biologists Ltd.

  18. Advancing biomaterials of human origin for tissue engineering

    OpenAIRE

    Chen, Fa-Ming; Liu, Xiaohua

    2015-01-01

    Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking in...

  19. Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser

    OpenAIRE

    Beloica Miloš; Vulićević Zoran R.; Mandinić Zoran; Radović Ivana; Jovičić Olivera; Carević Momir; Tekić Jasmina

    2014-01-01

    Goal of contemporary dentistry is to decrease the patient’s discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine) for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniqu...

  20. Injury Response of Resected Human Brain Tissue In Vitro

    NARCIS (Netherlands)

    Verwer, Ronald W. H.; Sluiter, Arja A.; Balesar, Rawien A.; Baaijen, Johannes C.; de Witt Hamer, Philip C.; Speijer, Dave; Li, Yichen; Swaab, Dick F.

    2015-01-01

    Brain injury affects a significant number of people each year. Organotypic cultures from resected normal neocortical tissue provide unique opportunities to study the cellular and neuropathological consequences of severe injury of adult human brain tissue in vitro. The in vitro injuries caused by

  1. Nigerian dental technology students and human immunodeficiency virus infection: knowledge, misconceptions and willingness to care.

    Science.gov (United States)

    Azodo, Cc; Omili, Ma; Akeredolu, Pa

    2014-05-01

    The rehabilitative dental care is important for maintaining adequate nutrition, guarding against wasting syndrome and malnutrition among human immunodeficiency virus (HIV)-infected individuals. The aim of this study is to determine the Nigerian dental technology students' knowledge and misconceptions about HIV infection and their willingness to care for HIV-infected patients. This descriptive cross-sectional study of dental technology students of Federal School of Dental Therapy and Technology Enugu, Nigeria was conducted in 2010. Data was subjected to descriptive, non-parametric and parametric statistics using the statistical package for the social sciences (SPSS) version 17.0 (Chicago Illinois, USA). P 4.0% (8/198) of the respondents erroneous described HIV as harmless, self-limitation and antibiotics responsive infection respectively. Of the respondents, 78.8% (156/198) and 83.3% (165/198) of them expressed willingness to care for HIV-infected patients and expressed need for training in the clinical care of HIV-infected patients respectively. Overall, the respondents opined that the dental therapists are the most suitable dental professional to pass HIV-related information to patients in the dental setting ahead of dentists and dental surgery assistants. The expressed willingness to care for HIV-infected patients, knowledge about the mode of HIV transmission and prevention among the respondents were high with existent misconceptions. There were no significant differences in the knowledge about HIV infection and willingness to care for HIV-infected patients among respondents in the lower class and those in upper class.

  2. Human Papilloma Virus (HPV) Oral Prevalence in Scotland (HOPSCOTCH): A Feasibility Study in Dental Settings.

    Science.gov (United States)

    Conway, David I; Robertson, Chris; Gray, Heather; Young, Linda; McDaid, Lisa M; Winter, Andrew J; Campbell, Christine; Pan, Jiafeng; Kavanagh, Kimberley; Kean, Sharon; Bhatia, Ramya; Cubie, Heather; Clarkson, Jan E; Bagg, Jeremy; Pollock, Kevin G; Cuschieri, Kate

    2016-01-01

    The purpose of this study was to test the feasibility of undertaking a full population investigation into the prevalence, incidence, and persistence of oral Human Papilloma Virus (HPV) in Scotland via dental settings. Male and female patients aged 16-69 years were recruited by Research Nurses in 3 primary care and dental outreach teaching centres and 2 General Dental Practices (GDPs), and by Dental Care Teams in 2 further GDPs. Participants completed a questionnaire (via an online tablet computer or paper) with socioeconomic, lifestyle, and sexual history items; and were followed up at 6-months for further questionnaire through appointment or post/online. Saline oral gargle/rinse samples, collected at baseline and follow-up, were subject to molecular HPV genotyping centrally. 1213 dental patients were approached and 402 individuals consented (participation rate 33.1%). 390 completed the baseline questionnaire and 380 provided a baseline oral specimen. Follow-up rate was 61.6% at 6 months. While recruitment was no different in Research Nurse vs Dental Care Team models the Nurse model ensured more rapid recruitment. There were relatively few missing responses in the questionnaire and high levels of disclosure of risk behaviours (99% answered some of the sexual history questions). Data linkage of participant data to routine health records including HPV vaccination data was successful with 99.1% matching. Oral rinse/gargle sample collection and subsequent HPV testing was feasible. Preliminary analyses found over 95% of samples to be valid for molecular HPV detection prevalence of oral HPV infection of 5.5% (95%CI 3.7, 8.3). It is feasible to recruit and follow-up dental patients largely representative / reflective of the wider population, suggesting it would be possible to undertake a study to investigate the prevalence, incidence, and determinants of oral HPV infection in dental settings.

  3. Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Jin Man Kim; Sang Wook Kang; Su-Mi Shin; Duck Su Kim; Kyong-Kyu Choi; Eun-Cheol Kim; Sun-Young Kim

    2014-01-01

    All-trans retinoic acid (ATRA) inhibits matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fibroblasts, skin fibroblasts, bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells (HDPCs). The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA (mRNA) expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction (PCR), respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol?L21 ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs, which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

  4. Biological Effects of Provisional Resin Materials on Human Dental Pulp Stem Cells.

    Science.gov (United States)

    Jun, S-K; Mahapatra, C; Lee, H-H; Kim, H-W; Lee, J-H

    This study investigated the in vitro cytotoxicity as well as the proinflammatory cytokine expression of provisional resin materials on primary cultured human dental pulp stem cells (hDPSCs). Five commercially available provisional resin materials were chosen (SNAP [SN], Luxatemp [LT], Jet [JE], Revotek LC [RL], and Vipi block [VB]). Eluates that were either polymerizing or already set were added to hDPSCs under serially diluted conditions divided into three different setting times (25% set, 50% set, and 100% set) and incubated for 24 hours with 2× concentrated culture media. Cell cytotoxicity tests were performed by LDH assay and live and dead confocal microscope images. The expression of proinflammatory cytokines in SN and VB was measured using cytokine antibody arrays. Data were analyzed using repeated measures analysis of variance (ANOVA) or ANOVA followed by the Tukey post hoc test at a significance level of pprovisional resin materials during polymerization (SN, LT, and JE) were cytotoxic to hDPSCs and may adversely affect pulp tissue.

  5. Pulse frequency dependency of photobiomodulation on the bioenergetic functions of human dental pulp stem cells.

    Science.gov (United States)

    Kim, Hong Bae; Baik, Ku Youn; Choung, Pill-Hoon; Chung, Jong Hoon

    2017-11-21

    Photobiomodulation (PBM) therapy contributes to pain relief, wound healing, and tissue regeneration. The pulsed wave (PW) mode has been reported to be more effective than the continuous wave (CW) mode when applying PBM to many biological systems. However, the reason for the higher effectiveness of PW-PBM is poorly understood. Herein, we suggest using delayed luminescence (DL) as a reporter of mitochondrial activity after PBM treatment. DL originates mainly from mitochondrial electron transport chain systems, which produce reactive oxygen species (ROS) and adenosine triphosphate (ATP). The decay time of DL depends on the pulse frequencies of applied light, which correlate with the biological responses of human dental pulp stem cells (hDPSCs). Using a low-power light whose wavelength is 810 nm and energy density is 38 mJ/cm 2 , we find that a 300-Hz pulse frequency prolonged the DL pattern and enhanced alkaline phosphatase activity. In addition, we analyze mitochondrial morphological changes and their volume density and find evidence supporting mitochondrial physiological changes from PBM treatment. Our data suggest a new methodology for determining the effectiveness of PBM and the specific pulse frequency dependency of PBM in the differentiation of hDPSCs.

  6. Sodium channel Nav1.7 immunoreactivity in painful human dental pulp and burning mouth syndrome

    Directory of Open Access Journals (Sweden)

    Yiangou Yiangos

    2010-06-01

    Full Text Available Abstract Background Voltage gated sodium channels Nav1.7 are involved in nociceptor nerve action potentials and are known to affect pain sensitivity in clinical genetic disorders. Aims and Objectives To study Nav1.7 levels in dental pulpitis pain, an inflammatory condition, and burning mouth syndrome (BMS, considered a neuropathic orofacial pain disorder. Methods Two groups of patients were recruited for this study. One group consisted of patients with dental pulpitis pain (n = 5 and controls (n = 12, and the other patients with BMS (n = 7 and controls (n = 10. BMS patients were diagnosed according to the International Association for the Study of Pain criteria; a pain history was collected, including the visual analogue scale (VAS. Immunohistochemistry with visual intensity and computer image analysis were used to evaluate levels of Nav1.7 in dental pulp tissue samples from the dental pulpitis group, and tongue biopsies from the BMS group. Results There was a significantly increased visual intensity score for Nav1.7 in nerve fibres in the painful dental pulp specimens, compared to controls. Image analysis showed a trend for an increase of the Nav1.7 immunoreactive % area in the painful pulp group, but this was not statistically significant. When expressed as a ratio of the neurofilament % area, there was a strong trend for an increase of Nav1.7 in the painful pulp group. Nav1.7 immunoreactive fibres were seen in abundance in the sub-mucosal layer of tongue biopsies, with no significant difference between BMS and controls. Conclusion Nav1.7 sodium channel may play a significant role in inflammatory dental pain. Clinical trials with selective Nav1.7 channel blockers should prioritise dental pulp pain rather than BMS.

  7. Sodium channel Nav1.7 immunoreactivity in painful human dental pulp and burning mouth syndrome

    Science.gov (United States)

    2010-01-01

    Background Voltage gated sodium channels Nav1.7 are involved in nociceptor nerve action potentials and are known to affect pain sensitivity in clinical genetic disorders. Aims and Objectives To study Nav1.7 levels in dental pulpitis pain, an inflammatory condition, and burning mouth syndrome (BMS), considered a neuropathic orofacial pain disorder. Methods Two groups of patients were recruited for this study. One group consisted of patients with dental pulpitis pain (n = 5) and controls (n = 12), and the other patients with BMS (n = 7) and controls (n = 10). BMS patients were diagnosed according to the International Association for the Study of Pain criteria; a pain history was collected, including the visual analogue scale (VAS). Immunohistochemistry with visual intensity and computer image analysis were used to evaluate levels of Nav1.7 in dental pulp tissue samples from the dental pulpitis group, and tongue biopsies from the BMS group. Results There was a significantly increased visual intensity score for Nav1.7 in nerve fibres in the painful dental pulp specimens, compared to controls. Image analysis showed a trend for an increase of the Nav1.7 immunoreactive % area in the painful pulp group, but this was not statistically significant. When expressed as a ratio of the neurofilament % area, there was a strong trend for an increase of Nav1.7 in the painful pulp group. Nav1.7 immunoreactive fibres were seen in abundance in the sub-mucosal layer of tongue biopsies, with no significant difference between BMS and controls. Conclusion Nav1.7 sodium channel may play a significant role in inflammatory dental pain. Clinical trials with selective Nav1.7 channel blockers should prioritise dental pulp pain rather than BMS. PMID:20529324

  8. Browning of Subcutaneous White Adipose Tissue in Humans

    OpenAIRE

    Sidossis, Labros S.; Porter, Craig; Saraf, Manish K.; Børsheim, Elisabet; Radhakrishnan, Ravi S.; Chao, Tony; Ali, Arham; Chondronikola, Maria; Mlcak, Ronald; Finnerty, Celeste C.; Hawkins, Hal K.; Toliver-Kinsky, Tracy; Herndon, David N.

    2015-01-01

    Since the presence of brown adipose tissue (BAT) was confirmed in adult humans, BAT has become a therapeutic target for obesity and insulin resistance. We examined whether human subcutaneous white adipose tissue (sWAT) can adopt a BAT-like phenotype using a clinical model of prolonged and severe adrenergic stress. sWAT samples were collected from severely burned and healthy individuals. A subset of burn victims were prospectively followed during their acute hospitalization. Browning of sWAT w...

  9. Microwave non-contact imaging of subcutaneous human body tissues.

    Science.gov (United States)

    Kletsov, Andrey; Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

    2015-10-01

    A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated.

  10. Lipolysis in human adipose tissue during exercise

    DEFF Research Database (Denmark)

    Lange, Kai Henrik Wiborg; Lorentsen, Jeanne; Isaksson, Fredrik

    2002-01-01

    exercise), as well as during non-steady-state (onset of exercise and early exercise) experimental settings. Fourteen healthy women [age: 74 +/- 1 (SE) yr] were studied at rest and during 60-min continuous bicycling at 60% of peak O(2) uptake. Calculated and measured subcutaneous abdominal adipose tissue...... venous glycerol concentrations increased substantially from rest to exercise but were similar both at rest and during later stages of exercise. In contrast, during the initial approximately 40 min of exercise, calculated glycerol concentration was significantly lower (approximately 40%) than measured...... and continuous prolonged exercise. However, during shorter periods of exercise (

  11. OCT4B1 Regulates the Cellular Stress Response of Human Dental Pulp Cells with Inflammation

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2017-01-01

    Full Text Available Introduction. Infection and apoptosis are combined triggers for inflammation in dental tissues. Octamer-binding transcription factor 4-B1 (OCT4B1, a novel spliced variant of OCT4 family, could respond to the cellular stress and possess antiapoptotic property. However, its specific role in dental pulpitis remains unknown. Methods. To investigate the effect of OCT4B1 on inflammation of dental pulp cells (DPCs, its expression in inflamed dental pulp tissues and DPCs was examined by in situ hybridization, real-time PCR, and FISH assay. OCT4B1 overexpressed DPCs model was established, confirmed by western blot and immunofluorescence staining, and then stimulated with Lipopolysaccharide (LPS. Apoptotic rate was determined by Hoechst/PI staining and FACS. Cell survival rate was calculated by CCK8 assay. Results. In situ hybridization, real-time PCR, and FISH assay revealed that OCT4B1 was extensively expressed in inflamed dental pulp tissues and DPCs with LPS stimulation. Western blot and immunofluorescence staining showed the expression of OCT4B1 and OCT4B increased after OCT4B1 transfection. Hoechst/PI staining and FACS demonstrated that less red/blue fluorescence was detected and apoptotic percentage decreased (3.45% after transfection. CCK8 demonstrated that the survival rate of pCDH-OCT4B1-flag cells increased. Conclusions. OCT4B1 plays an essential role in inflammation and apoptosis of DPCs. OCT4B might operate synergistically with OCT4B1 to reduce apoptosis.

  12. Mechanical properties of human atherosclerotic intima tissue.

    Science.gov (United States)

    Akyildiz, Ali C; Speelman, Lambert; Gijsen, Frank J H

    2014-03-03

    Progression and rupture of atherosclerotic plaques in coronary and carotid arteries are the key processes underlying myocardial infarctions and strokes. Biomechanical stress analyses to compute mechanical stresses in a plaque can potentially be used to assess plaque vulnerability. The stress analyses strongly rely on accurate representation of the mechanical properties of the plaque components. In this review, the composition of intima tissue and how this changes during plaque development is discussed from a mechanical perspective. The plaque classification scheme of the American Heart Association is reviewed and plaques originating from different vascular territories are compared. Thereafter, an overview of the experimental studies on tensile and compressive plaque intima properties are presented and the results are linked to the pathology of atherosclerotic plaques. This overview revealed a considerable variation within studies, and an enormous dispersion between studies. Finally, the implications of the dispersion in experimental data on the clinical applications of biomechanical plaque modeling are presented. Suggestions are made on mechanical testing protocol for plaque tissue and on using a standardized plaque classification scheme. This review identifies the current status of knowledge on plaque mechanical properties and the future steps required for a better understanding of the plaque type specific material properties. With this understanding, biomechanical plaque modeling may eventually provide essential support for clinical plaque risk stratification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Geometry Modeling Program Implementation of Human Hip Tissue

    Directory of Open Access Journals (Sweden)

    WANG Mo-nan

    2017-10-01

    Full Text Available Abstract:Aiming to design a simulate software of human tissue modeling and analysis,Visual Studio 2010 is selected as a development tool to develop a 3 D reconstruction software of human tissue with language C++.It can be used alone. It also can be a module of the virtual surgery systems. The system includes medical image segmentation modules and 3 D reconstruction modules,and can realize the model visualization. This software system has been used to reconstruct hip muscles,femur and hip bone accurately. The results show these geometry models can simulate the structure of hip tissues.

  14. Geometry Modeling Program Implementation of Human Hip Tissue

    Directory of Open Access Journals (Sweden)

    WANG Monan

    2017-04-01

    Full Text Available Aiming to design a simulate software of human tissue modeling and analysis,Visual Studio 2010 is selected as a development tool to develop a 3 D reconstruction software of human tissue with language C++.It can be used alone. It also can be a module of the virtual surgery systems. The system includes medical image segmentation modules and 3 D reconstruction modules,and can realize the model visualization. This software system has been used to reconstruct hip muscles,femur and hip bone accurately. The results show these geometry models can simulate the structure of hip tissues.

  15. Vibrational Micro-Spectroscopy of Human Tissues Analysis: Review.

    Science.gov (United States)

    Bunaciu, Andrei A; Hoang, Vu Dang; Aboul-Enein, Hassan Y

    2017-05-04

    Vibrational spectroscopy (Infrared (IR) and Raman) and, in particular, micro-spectroscopy and micro-spectroscopic imaging have been used to characterize developmental changes in tissues, to monitor these changes in cell cultures and to detect disease and drug-induced modifications. The conventional methods for biochemical and histophatological tissue characterization necessitate complex and "time-consuming" sample manipulations and the results are rarely quantifiable. The spectroscopy of molecular vibrations using mid-IR or Raman techniques has been applied to samples of human tissue. This article reviews the application of these vibrational spectroscopic techniques for analysis of biological tissue published between 2005 and 2015.

  16. Comparison of osteo/odontogenic differentiation of human adult dental pulp stem cells and stem cells from apical papilla in the presence of platelet lysate.

    Science.gov (United States)

    Abuarqoub, Duaa; Awidi, Abdalla; Abuharfeil, Nizar

    2015-10-01

    Human dental pulp cells (DPSCs) and stem cells from apical papilla have been used for the repair of damaged tooth tissues. Human platelet lysate (PL) has been suggested as a substitute for fetal bovine serum (FBS) for large scale expansion of dental stem cells. However, biological effects and optimal concentrations of PL for proliferation and differentiation of human dental stem cells remain to be elucidated. DPSCs and SCAP cells were isolated from impacted third molars of young healthy donors, at the stage of root development and identified by markers using flow cytometry. For comparison the cells were cultured in media containing PL (1%, 5% and 10%) and FBS, with subsequent induction for osteogenic/odontogenic differentiation. The cultures were analyzed for; morphology, growth characteristics, mineralization potential (Alizarin Red method) and differentiation markers using ELISA and real time -polymerase chain reaction (qPCR). The proliferation rates of DPSCs and SCAP significantly increased when cells were treated with 5% PL (7X doubling time) as compared to FBS. 5% PL also enhanced mineralized differentiation of DPSCs and SCAP, as indicated by the measurement of alkaline phosphatase activity, osteocalcin and osteopontin, calcium deposition and q-PCR. Our findings suggest that using 5% platelet lysate, proliferation and osteo/odontogenesis of DPSCs and SCAP for a short period of time (15 days), was significantly improved. This may imply its use as an optimum concentration for expansion of dental stem cells in bone regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Human tissue models in cancer research: looking beyond the mouse

    Directory of Open Access Journals (Sweden)

    Samuel J. Jackson

    2017-08-01

    Full Text Available Mouse models, including patient-derived xenograft mice, are widely used to address questions in cancer research. However, there are documented flaws in these models that can result in the misrepresentation of human tumour biology and limit the suitability of the model for translational research. A coordinated effort to promote the more widespread development and use of ‘non-animal human tissue’ models could provide a clinically relevant platform for many cancer studies, maximising the opportunities presented by human tissue resources such as biobanks. A number of key factors limit the wide adoption of non-animal human tissue models in cancer research, including deficiencies in the infrastructure and the technical tools required to collect, transport, store and maintain human tissue for lab use. Another obstacle is the long-standing cultural reliance on animal models, which can make researchers resistant to change, often because of concerns about historical data compatibility and losing ground in a competitive environment while new approaches are embedded in lab practice. There are a wide range of initiatives that aim to address these issues by facilitating data sharing and promoting collaborations between organisations and researchers who work with human tissue. The importance of coordinating biobanks and introducing quality standards is gaining momentum. There is an exciting opportunity to transform cancer drug discovery by optimising the use of human tissue and reducing the reliance on potentially less predictive animal models.

  18. Functional Characterization of Preadipocytes Derived from Human Periaortic Adipose Tissue

    Directory of Open Access Journals (Sweden)

    Diana Vargas

    2017-01-01

    Full Text Available Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases.

  19. Studies on the composition of human dental calculus

    International Nuclear Information System (INIS)

    Molokhia, A.; Nixon, G.S.

    1984-01-01

    The concentrations of Ca, Mg, Na, K, Cl, Zn, Sr, Mn, Ba, Br and Au were determined in individual samples of dental calculus collected from patients resident in the Manchester area. The method used was instrumental neutron activation analysis, combined with gamma-spectrometry. The highest and lowest values of Sr were found in calculus from patients of Asian origin. No differences were found in the elements studied with regard to sex or age. Individual variations were highest in Au and lowest in Ca. (author)

  20. A family of hyperelastic models for human brain tissue

    Science.gov (United States)

    Mihai, L. Angela; Budday, Silvia; Holzapfel, Gerhard A.; Kuhl, Ellen; Goriely, Alain

    2017-09-01

    Experiments on brain samples under multiaxial loading have shown that human brain tissue is both extremely soft when compared to other biological tissues and characterized by a peculiar elastic response under combined shear and compression/tension: there is a significant increase in shear stress with increasing axial compression compared to a moderate increase with increasing axial tension. Recent studies have revealed that many widely used constitutive models for soft biological tissues fail to capture this characteristic response. Here, guided by experiments of human brain tissue, we develop a family of modeling approaches that capture the elasticity of brain tissue under varying simple shear superposed on varying axial stretch by exploiting key observations about the behavior of the nonlinear shear modulus, which can be obtained directly from the experimental data.

  1. The performance of human dental pulp stem cells on different three-dimensional scaffold materials.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Kuppevelt, A.H.M.S.M. van; Daamen, W.F.; Bian, Z.; Jansen, J.A.

    2006-01-01

    The aim of this study was to investigate the in vitro and in vivo behavior of human dental pulp stem cells (DPSCs) isolated from impacted third molars, when seeded onto different 3-dimensional (3-D) scaffold materials: i.e. a spongeous collagen, a porous ceramic, and a fibrous titanium mesh.

  2. Comparative in silico profiling of epigenetic modifiers in human tissues.

    Science.gov (United States)

    Son, Mi-Young; Jung, Cho-Rok; Kim, Dae-Soo; Cho, Hyun-Soo

    2018-04-06

    The technology of tissue differentiation from human pluripotent stem cells has attracted attention as a useful resource for regenerative medicine, disease modeling and drug development. Recent studies have suggested various key factors and specific culture methods to improve the successful tissue differentiation and efficient generation of human induced pluripotent stem cells. Among these methods, epigenetic regulation and epigenetic signatures are regarded as an important hurdle to overcome during reprogramming and differentiation. Thus, in this study, we developed an in silico epigenetic panel and performed a comparative analysis of epigenetic modifiers in the RNA-seq results of 32 human tissues. We demonstrated that an in silico epigenetic panel can identify epigenetic modifiers in order to overcome epigenetic barriers to tissue-specific differentiation.

  3. Hypoxia-Inducible Factor-1α: A Potential Factor for the Enhancement of Osseointegration between Dental Implants and Tissue-Engineered Bone

    Directory of Open Access Journals (Sweden)

    Duohong Zou

    2011-07-01

    Full Text Available Introduction: Tissue-engineered bones are widely utilized to protect healthy tissue, reduce pain, and increase the success rate of dental implants. one of the most challenging obstacles lies in obtaining effective os-seointegration between dental implants and tissue-engineered structures. Deficiencies in vascularization, osteogenic factors, oxygen, and other nutrients inside the tissue-engineered bone during the early stages following implantation all inhibit effective osseointe-gration. Oxygen is required for aerobic metabolism in bone and blood vessel tissues, but oxygen levels inside tissue-engineered bone are not suf-ficient for cell proliferation. HIF-1α is a pivotal regulator of hypoxic and ischemic vascular responses, driving transcriptional activation of hundreds of genes involved in vascular reactivity, angiogenesis, arteriogenesis, and osteogenesis.The hypothesis: Hypoxia-Inducible Factor-1α seems a potential factor for the enhancement of osseointegration between dental implants and tissue-engineered bone.Evaluation of the hypothesis: Enhancement of HIF-1α protein expression is recognized as the most promising approach for angiogenesis, because it can induce multiple angiogenic targets in a coordinated manner. Therefore, it will be a novel potential therapeutic methods targeting HIF-1α expression to enhance osseointegration be-tween dental implants and tissue-engineered bone.

  4. Investigations of some elements distribution in dental tissues by INAA as a function of ecological and some other parameters

    International Nuclear Information System (INIS)

    Draskovic, R.J.; Jacimovic, Lj.; Stojicevic, M.; Pajic, P.; Filipovic, V.

    1982-01-01

    Distribution of some elements (Hg, Zn, Sb, Co and Sc) in dental tissues (enamel, dentine, pulp) has been investiaated by instrumental neutron activation analysis (INAA). Teeth samples were taken from patients living in different regions (mine and mineralized areas, plain), taking into account the following parameters: ecological conditions, age of patients, stomatological operations and use of local cosmetic preparations containig mercury. Samples of vegetation (beech, moss, pine) from two locations belonging to regions of mineralized areas also were analyzed. Results of our investigations are presented and discussed. (author)

  5. Human perception of dental porcelain translucency correlated to spectrophotometric measurements.

    Science.gov (United States)

    Liu, Min-Chieh; Aquilino, Steven A; Lund, Peter S; Vargas, Marcos A; Diaz-Arnold, Ana M; Gratton, David G; Qian, Fang

    2010-04-01

    This study evaluated the relationship between instrumental measurements and subjective visual assessment of differences in dental porcelain translucency. Unshaded feldspathic porcelain was used with controlled amounts of tin oxide to create two groups of 12-mm diameter disks with incremental changes in opacity. Contrast ratio (CR = Yb/Yw) was determined with a spectrophotometer, and used as a measure of porcelain translucency (Group A = 0.20 to 0.40; Group B = 0.6-0.8). Within each group, there were 14 specimens with 11 CRs. Three observer groups (first year dental students, residents, faculty with >10 years of shade matching experience) were recruited to assess the translucency between porcelain disks under two lighting conditions (reflected light, transmitted light). Each subject's ability to distinguish between specimens of differing translucency was determined. Descriptive statistics and three-way ANOVA followed by a post-hoc Tukey-Kramer test were used to evaluate the translucency perception threshold (TPT) of subjects (alpha= 0.05). The overall mean TPT (DeltaC) was 0.07, while 50% of the subjects could perceive a 0.06 CR difference between porcelain specimens. Three-way ANOVA revealed a significant difference in translucency perception among the observer groups (p or =10 years) significantly improved the ability to perceive differences in translucency; however, neither the viewing condition nor porcelain opacity affected the perceived translucency threshold.

  6. Genetic effects on gene expression across human tissues

    NARCIS (Netherlands)

    Battle, Alexis; Brown, Christopher D.; Engelhardt, Barbara E.; Montgomery, Stephen B.; Aguet, François; Ardlie, Kristin G.; Cummings, Beryl B.; Gelfand, Ellen T.; Getz, Gad; Hadley, Kane; Handsaker, Robert E.; Huang, Katherine H.; Kashin, Seva; Karczewski, Konrad J.; Lek, Monkol; Li, Xiao; MacArthur, Daniel G.; Nedzel, Jared L.; Nguyen, Duyen T.; Noble, Michael S.; Segrè, Ayellet V.; Trowbridge, Casandra A.; Tukiainen, Taru; Abell, Nathan S.; Balliu, Brunilda; Barshir, Ruth; Basha, Omer; Bogu, Gireesh K.; Brown, Andrew; Castel, Stephane E.; Chen, Lin S.; Chiang, Colby; Conrad, Donald F.; Cox, Nancy J.; Damani, Farhan N.; Davis, Joe R.; Delaneau, Olivier; Dermitzakis, Emmanouil T.; Eskin, Eleazar; Ferreira, Pedro G.; Frésard, Laure; Gamazon, Eric R.; Garrido-Martín, Diego; Gewirtz, Ariel D. H.; Gliner, Genna; Gloudemans, Michael J.; Guigo, Roderic; Hall, Ira M.; Han, Buhm; He, Yuan

    2017-01-01

    Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression

  7. In vitro pharmacological characterization of a novel TRPA1 antagonist and proof of mechanism in a human dental pulp model

    Directory of Open Access Journals (Sweden)

    Nyman E

    2013-01-01

    Full Text Available Eva Nyman,1,* Bo Franzén,1,* Andreas Nolting,1 Göran Klement,1 Gang Liu,1 Maria Nilsson,1 Annika Rosén,2 Charlotta Björk,3 Dirk Weigelt,4 Patrik Wollberg,1 Paul Karila,1 Patrick Raboisson11Neuroscience, Innovative Medicines CNS/Pain, AstraZeneca R&D, Södertälje, Sweden; 2Division of Oral and Maxillofacial Surgery, Karolinska Institute/Karolinska University Hospital, Huddinge, Sweden; 3Clinical TA NS Early Development, 4Medicinal Chemistry, Innovative Medicines CNS/Pain, AstraZeneca R&D, Södertälje, Sweden*These authors contributed equally to this workAbstract: AZ465 is a novel selective transient receptor potential cation channel, member A1 (TRPA1 antagonist identified during a focused drug discovery effort. In vitro, AZ465 fully inhibits activation by zinc, O-chlorobenzylidene malononitrile (CS, or cinnamaldehyde of the human TRPA1 channel heterologously expressed in human embryonic kidney cells. Our data using patch-clamp recordings and mouse/human TRPA1 chimeras suggest that AZ465 binds reversibly in the pore region of the human TRPA1 channel. Finally, in an ex vivo model measuring TRPA1 agonist-stimulated release of neuropeptides from human dental pulp biopsies, AZD465 was able to block 50%–60% of CS-induced calcitonin gene-related peptide release, confirming that AZ465 inhibits the native human TRPA1 channel in neuronal tissue.Keywords: pain, pharmacology, antagonist, chimeric proteins, dental pulp, inflammation, neuropeptide, calcitonin gene-related peptide, CGRP

  8. Neuronal regeneration in injured rat spinal cord after human dental pulp derived neural crest stem cell transplantation.

    Science.gov (United States)

    Kabatas, S; Demir, C S; Civelek, E; Yilmaz, I; Kircelli, A; Yilmaz, C; Akyuva, Y; Karaoz, E

    2018-01-01

    This study aimed to analyze the effect of human Dental Pulp-Neural Crest Stem Cells (hDP-NCSCs) delivery on lesion site after spinal cord injury (SCI), and to observe the functional recovery after transplantation. Neural Crest Stem Cells (NCSCs) were isolated from human Dental Pulp (hDP). The experimental rat population was divided into four groups (n = 6/24). Their behavioral motility was scored regularly. After 4-weeks, rats were sacrificed, and their spinal cords were examined for Green Fluorescent Protein (GFP) labeled hDP-NCSCs by immunofluorescence (IF) staining. In early post-injury (p.i) period, the ultrastructure of spinal cord tissue was preserved in Group 4. The majority of cells forming the ependymal region around the central canal were found to be hDP-NCSCs. While the grey-and-white-matter around the ependymal region was composed of e.g. GFP cells, with astrocytic-like appearance. The scores showed significant motor recovery in hind limb functions in Group 4. However, no obvious change was observed in other groups. Cells e.g., mesenchymal (Vimentin+) which express GFP+ cells in the gray-and-white-matter around the ependymal region could indicate the potential to self-renewal and plasticity. Thus, transplantation of hDP-NCSCs might be an effective strategy to improve functional recovery following spinal cord trauma (Fig. 10, Ref. 32).

  9. Study and structural and chemical characterization of human dental smalt by electron microscopy

    International Nuclear Information System (INIS)

    Belio R, I.A.; Reyes G, J.

    1998-01-01

    The study of human dental smalt has been subject to investigation for this methods with electron microscopy, electron diffraction, X-ray diffraction and image simulation programs have been used with the purpose to determine its chemical and structural characteristics of the organic and inorganic materials. This work has been held mainly for the characterization of hydroxyapatite (Ca) 10 (PO 4 ) 6 (OH 4 ) 2 , inorganic material which conforms the dental smalt in 97%, so observing its structural unity which is composed by the prisms and these by crystals and atoms. It was subsequently initiated the study of the organic material, with is precursor of itself. (Author)

  10. 21 CFR 876.5885 - Tissue culture media for human ex vivo tissue and cell culture processing applications.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tissue culture media for human ex vivo tissue and cell culture processing applications. 876.5885 Section 876.5885 Food and Drugs FOOD AND DRUG... DEVICES Therapeutic Devices § 876.5885 Tissue culture media for human ex vivo tissue and cell culture...

  11. [Ru(bipy)3]2+ nanoparticle-incorporate dental light cure resin to promote photobiomodulation therapy for enhanced vital pulp tissue repair

    Science.gov (United States)

    Mosca, Rodrigo C.; Young, Nicholas; Zeituni, Carlos A.; Arany, Praveen R.

    2018-02-01

    The use of nanoparticle on dental light cure resin is not new, currently several compounds (nanoadditives) are used to promote better communication between the restorative material and biological tissues. The interest for this application is growing up to enhance mechanical proprieties to dental tissue cells regeneration. Bioactive nanoparticles and complex compounds with multiple functions are the major target for optimizing the restorative materials. In this work, we incorporate [Ru(bipy)3]2+ nanoparticles, that absorbs energy at 450 nm (blue-light) and emits strongly at 620 nm (red-light), in PLGA Microspheres and insert it in Dental Light Cure Resin to promote the Photobiomodulation Therapy (PBM) effects to accelerate dental pulp repair by in vitro using cytotoxicity and proliferation assay.

  12. Distribution of class ii major histocompatibility complex antigenexpressing cells in human dental pulp with carious lesions

    Directory of Open Access Journals (Sweden)

    Tetiana Haniastuti

    2012-09-01

    Full Text Available Background: Dental caries is a bacterial infection which causes destruction of the hard tissues of the tooth. Exposure of the dentin to the oral environment as a result of caries inevitably results in a cellular response in the pulp. The major histocompatibility complex (MHC is a group of genes that code for cell-surface histocompatibility antigens. Cells expressing class II MHC molecules participate in the initial recognition and the processing of antigenic substances to serve as antigen-presenting cells. Purpose: The aim of the study was to elucidate the alteration in the distribution of class II MHC antigen-expressing cells in human dental pulp as carious lesions progressed toward the pulp. Methods: Fifteen third molars with caries at the occlusal site at various stages of decay and 5 intact third molars were extracted and used in this study. Before decalcifying with 10% EDTA solution (pH 7.4, all the samples were observed by micro-computed tomography to confirm the lesion condition three-dimensionally. The specimens were then processed for cryosection and immunohistochemistry using an anti-MHC class II monoclonal antibody. Results: Class II MHC antigen-expressing cells were found both in normal and carious specimens. In normal tooth, the class II MHC-immunopositive cells were observed mainly at the periphery of the pulp tissue. In teeth with caries, class II MHC-immunopositive cells were located predominantly subjacent to the carious lesions. As the caries progressed, the number of class II MHC antigen-expressing cells was increased. Conclusion: The depth of carious lesions affects the distribution of class II MHC antigen-expressing cells in the dental pulp.Latar belakang: Karies merupakan penyakit infeksi bakteri yang mengakibatkan destruksi jaringan keras gigi. Dentin yang terbuka akibat karies akan menginduksi respon imun seluler pada pulpa. Kompleks histokompatibilitas utama (MHC merupakan sekumpulan gen yang mengkode histokompatibilitas

  13. Immunolocalization of transforming growth factor alpha in normal human tissues

    DEFF Research Database (Denmark)

    Christensen, M E; Poulsen, Steen Seier

    1996-01-01

    anchorage-independent growth of normal cells and was, therefore, considered as an "oncogenic" growth factor. Later, its immunohistochemical presence in normal human cells as well as its biological effects in normal human tissues have been demonstrated. The aim of the present investigation was to elucidate...... the distribution of the growth factor in a broad spectrum of normal human tissues. Indirect immunoenzymatic staining methods were used. The polypeptide was detected with a polyclonal as well as a monoclonal antibody. The polyclonal and monoclonal antibodies demonstrated almost identical immunoreactivity. TGF......-alpha was found to be widely distributed in cells of normal human tissues derived from all three germ layers, most often in differentiated cells. In epithelial cells, three different kinds of staining patterns were observed, either diffuse cytoplasmic, cytoplasmic in the basal parts of the cells, or distinctly...

  14. Dental Calculus Arrest of Dental Caries

    OpenAIRE

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human t...

  15. The prevalence, pattern and clinical presentation of developmental dental hard-tissue anomalies in children with primary and mix dentition from Ile-Ife, Nigeria

    OpenAIRE

    Temilola, Dada Oluwaseyi; Folayan, Morenike Oluwatoyin; Fatusi, Olawunmi; Chukwumah, Nneka Maureen; Onyejaka, Nneka; Oziegbe, Elizabeth; Oyedele, Titus; Kolawole, Kikelomo Adebanke; Agbaje, Hakeem

    2014-01-01

    Background The study of dental anomalies is important because it generates information that is important for both the anthropological and clinical management of patients. The objective of this study is to determine the prevalence and pattern of presentation of dental hard-tissue developmental anomalies in the mix dentition of children residing in Ile-Ife, a suburban region of Nigeria. Methods Information on age, sex and socioeconomic status was collected from 1,036 children aged four months t...

  16. Human natural killer cell development in secondary lymphoid tissues

    Science.gov (United States)

    Freud, Aharon G.; Yu, Jianhua; Caligiuri, Michael A.

    2014-01-01

    For nearly a decade it has been appreciated that critical steps in human natural killer (NK) cell development likely occur outside of the bone marrow and potentially necessitate distinct microenvironments within extramedullary tissues. The latter include the liver and gravid uterus as well as secondary lymphoid tissues such as tonsils and lymph nodes. For as yet unknown reasons these tissues are naturally enriched with NK cell developmental intermediates (NKDI) that span a maturation continuum starting from an oligopotent CD34+CD45RA+ hematopoietic precursor cell to a cytolytic mature NK cell. Indeed despite the detection of NKDI within the aforementioned tissues, relatively little is known about how, why, and when these tissues may be most suited to support NK cell maturation and how this process fits in with other components of the human immune system. With the discovery of other innate lymphoid subsets whose immunophenotypes overlap with those of NKDI, there is also need to revisit and potentially re-characterize the basic immunophenotypes of the stages of the human NK cell developmental pathway in vivo. In this review, we provide an overview of human NK cell development in secondary lymphoid tissues and discuss the many questions that remain to be answered in this exciting field. PMID:24661538

  17. Mechanized syringe homogenization of human and animal tissues.

    Science.gov (United States)

    Kurien, Biji T; Porter, Andrew C; Patel, Nisha C; Kurono, Sadamu; Matsumoto, Hiroyuki; Scofield, R Hal

    2004-06-01

    Tissue homogenization is a prerequisite to any fractionation schedule. A plethora of hands-on methods are available to homogenize tissues. Here we report a mechanized method for homogenizing animal and human tissues rapidly and easily. The Bio-Mixer 1200 (manufactured by Innovative Products, Inc., Oklahoma City, OK) utilizes the back-and-forth movement of two motor-driven disposable syringes, connected to each other through a three-way stopcock, to homogenize animal or human tissue. Using this method, we were able to homogenize human or mouse tissues (brain, liver, heart, and salivary glands) in 5 min. From sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and a matrix-assisted laser desorption/ionization time-of-flight mass spectrometric enzyme assay for prolidase, we have found that the homogenates obtained were as good or even better than that obtained used a manual glass-on-Teflon (DuPont, Wilmington, DE) homogenization protocol (all-glass tube and Teflon pestle). Use of the Bio-Mixer 1200 to homogenize animal or human tissue precludes the need to stay in the cold room as is the case with the other hands-on homogenization methods available, in addition to freeing up time for other experiments.

  18. Knowledge and attitude of Indian clinical dental students towards the dental treatment of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS).

    Science.gov (United States)

    Oberoi, Sukhvinder Singh; Marya, Charu Mohan; Sharma, Nilima; Mohanty, Vikrant; Marwah, Mohita; Oberoi, Avneet

    2014-12-01

    Oral health care of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS) is a growing area of concern. Information on HIV- and AIDS-related knowledge among dental students provides a crucial foundation for efforts aimed at developing an appropriate dental curriculum on HIV and AIDS. The purpose of this study was to assess the knowledge and attitude of Indian clinical dental students towards the treatment of patients with HIV/AIDS and perceived sources of information regarding HIV-related issues. Data were collected from clinical dental students (third year, fourth year and internship) from three dental institutions in Delhi National Capital Region (NCR). The questions assessed the knowledge and attitude towards treatment of patients with HIV and the perceived source of information related to HIV. The willingness to treat HIV-positive patients among dental students was 67.0%, and 74.20% were confident of treating a patient with HIV/AIDS. The potential problems in rendering treatment to these patients were effect on the attitude of other patients (49.90%) and staff fears (52.50%). The correct knowledge regarding the infection-control practice (barrier technique) was found among only 15.50% of respondents. The respondents had sufficient knowledge regarding the oral manifestations of HIV/AIDS. There was no correlation between the knowledge and attitude score, demonstrating a gap between knowledge and attitude among dental students regarding treatment of HIV-infected patients. Appropriate knowledge has to be delivered through the dental education curriculum, which can instil confidence in students about their ability to manage HIV-positive patients. © 2014 FDI World Dental Federation.

  19. Astrocyte calcium signal and gliotransmission in human brain tissue.

    Science.gov (United States)

    Navarrete, Marta; Perea, Gertrudis; Maglio, Laura; Pastor, Jesús; García de Sola, Rafael; Araque, Alfonso

    2013-05-01

    Brain function is recognized to rely on neuronal activity and signaling processes between neurons, whereas astrocytes are generally considered to play supportive roles for proper neuronal function. However, accumulating evidence indicates that astrocytes sense and control neuronal and synaptic activity, indicating that neuron and astrocytes reciprocally communicate. While this evidence has been obtained in experimental animal models, whether this bidirectional signaling between astrocytes and neurons occurs in human brain remains unknown. We have investigated the existence of astrocyte-neuron communication in human brain tissue, using electrophysiological and Ca(2+) imaging techniques in slices of the cortex and hippocampus obtained from biopsies from epileptic patients. Cortical and hippocampal human astrocytes displayed spontaneous Ca(2+) elevations that were independent of neuronal activity. Local application of transmitter receptor agonists or nerve electrical stimulation transiently elevated Ca(2+) in astrocytes, indicating that human astrocytes detect synaptic activity and respond to synaptically released neurotransmitters, suggesting the existence of neuron-to-astrocyte communication in human brain tissue. Electrophysiological recordings in neurons revealed the presence of slow inward currents (SICs) mediated by NMDA receptor activation. The frequency of SICs increased after local application of ATP that elevated astrocyte Ca(2+). Therefore, human astrocytes are able to release the gliotransmitter glutamate, which affect neuronal excitability through activation of NMDA receptors in neurons. These results reveal the existence of reciprocal signaling between neurons and astrocytes in human brain tissue, indicating that astrocytes are relevant in human neurophysiology and are involved in human brain function.

  20. Polychlorinated naphthalenes in human adipose tissue from New York, USA

    International Nuclear Information System (INIS)

    Kunisue, Tatsuya; Johnson-Restrepo, Boris; Hilker, David R.; Aldous, Kenneth M.; Kannan, Kurunthachalam

    2009-01-01

    Polychlorinated naphthalenes (PCNs) are persistent, bioaccumulative, and toxic contaminants. Prior to this study, the occurrence of PCNs in human adipose tissues from the USA has not been analyzed. Here, we have measured concentrations of PCNs in human adipose tissue samples collected in New York City during 2003-2005. Concentrations of PCNs were in the range of 61-2500 pg/g lipid wt. in males and 21-910 pg/g lipid wt. in females. PCN congeners 52/60 (1,2,3,5,7/1,2,4,6,7) and 66/67 (1,2,3,4,6,7/1,2,3,5,6,7) were predominant, collectively accounting for 66% of the total PCN concentrations. Concentrations of PCNs in human adipose tissues were 2-3 orders of magnitude lower than the previously reported concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Concentrations of PCNs were not correlated with PCB concentrations. The contribution of PCNs to dioxin-like toxic equivalents (TEQs) in human adipose tissues was estimated to be <1% of the polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F)-TEQs. - Polychlorinated naphthalenes have been measured in human adipose tissues from the USA for the first time

  1. Predicting Tissue-Specific Enhancers in the Human Genome

    Energy Technology Data Exchange (ETDEWEB)

    Pennacchio, Len A.; Loots, Gabriela G.; Nobrega, Marcelo A.; Ovcharenko, Ivan

    2006-07-01

    Determining how transcriptional regulatory signals areencoded in vertebrate genomes is essential for understanding the originsof multi-cellular complexity; yet the genetic code of vertebrate generegulation remains poorly understood. In an attempt to elucidate thiscode, we synergistically combined genome-wide gene expression profiling,vertebrate genome comparisons, and transcription factor binding siteanalysis to define sequence signatures characteristic of candidatetissue-specific enhancers in the human genome. We applied this strategyto microarray-based gene expression profiles from 79 human tissues andidentified 7,187 candidate enhancers that defined their flanking geneexpression, the majority of which were located outside of knownpromoters. We cross-validated this method for its ability to de novopredict tissue-specific gene expression and confirmed its reliability in57 of the 79 available human tissues, with an average precision inenhancer recognition ranging from 32 percent to 63 percent, and asensitivity of 47 percent. We used the sequence signatures identified bythis approach to assign tissue-specific predictions to ~;328,000human-mouse conserved noncoding elements in the human genome. Byoverlapping these genome-wide predictions with a large in vivo dataset ofenhancers validated in transgenic mice, we confirmed our results with a28 percent sensitivity and 50 percent precision. These results indicatethe power of combining complementary genomic datasets as an initialcomputational foray into the global view of tissue-specific generegulation in vertebrates.

  2. Human dental enamel and dentin structural effects after Er:YAG laser irradiation.

    Science.gov (United States)

    Lima, Darlon Martíns; Tonetto, Mateus Rodrigues; de Mendonça, Adriano Augusto Melo; Elossais, André Afif; Saad, José Roberto Cury; de Andrade, Marcelo Ferrarezi; Pinto, Shelon Cristina Souza; Bandéca, Matheus Coelho

    2014-05-01

    Ideally projected to be applied on soft tissues, infrared lasers were improved by restorative dentistry to be used in hard dental tissues cavity preparations--namely enamel and dentin. This paper evidentiates the relevant aspects of infrared Erbium laser's action mechanism and its effects, and characterizes the different effects deriving from the laser's beams emission. The criteria for use and selection of optimal parameters for the correct application of laser systems and influence of supporting factors on the process, such as water amount and its presence in the ablation process, protection exerted by the plasma shielding and structural factors, which are indispensable in dental tissues cavity preparation related to restorative technique, are subordinated to optical modifications caused by the interaction of the energy dissipated by these laser light emission systems in the targeted tissue substrate. Differences in the action of infrared Erbium laser system in regard to the nature of the ablation process and variations on the morphological aspects observed in the superficial structure of the target tissue irradiated, may be correlated to the structural optical modifications of the substrate produced by an interaction of the energy propagated by laser systems.

  3. In vitro study of the diode laser effect on artificial demineralized surface of human dental enamel

    International Nuclear Information System (INIS)

    Ebel, Patricia

    2003-01-01

    In scientific literature there are many reports about fusion and resolidification of dental enamel after laser irradiation and their capability to generate surfaces with increased resistance to demineralization compared to non-irradiated areas. The use of high power diode laser on demineralized surfaces of human dental enamel is presented as a good alternative in caries prevention. The purpose of this study is to investigate the morphological changes produced by the use of one high power diode laser on human dental enamel surface after demineralization treatment with lactic acid, under chosen parameters. Fifteen samples of human dental molars were used and divided in four groups: control - demineralization treatment with lactic acid and no irradiation, and demineralization treatment with lactic acid followed of irradiation with 212,20 mJ/cm 2 , 282,84 mJ/cm 2 and 325,38 mJ/cm 2 , respectively. The samples were irradiated with high power diode laser (808 nm) with a 300 μm diameter fiber optics. Black ink was used on enamel surface to enhance the superficial absorption. The samples were studied by optical microscopy and scanning electron microscopy. Modifications on the enamel surfaces were observed. Such modifications were characterized by melted and re-solidified region of the enamel. According with our results the best parameter was 2.0 W, presenting the most uniform surface. The use of high power diode laser as demonstrated in this study is able to promote melting and re-solidification on human dental enamel. (author)

  4. Characterization of muscarinic receptor subtypes in human tissues

    International Nuclear Information System (INIS)

    Giraldo, E.; Martos, F.; Gomez, A.; Garcia, A.; Vigano, M.A.; Ladinsky, H.; Sanchez de La Cuesta, F.

    1988-01-01

    The affinities of selective, pirenzepine and AF-DX 116, and classical, N-methylscopolamine and atropine, muscarinic cholinergic receptor antagonists were investigated in displacement binding experiments with [ 3 H]Pirenzepine and [ 3 H]N-methylscopolamine in membranes from human autoptic tissues (forebrain, cerebellum, atria, ventricle and submaxillary salivary glands). Affinity estimates of N-methylscopolamine and atropine indicated a non-selective profile. Pirenzepine showed differentiation between the M 1 neuronal receptor of the forebrain and the receptors in other tissues while AF-DX 116 clearly discriminated between muscarinic receptors of heart and glands. The results in human tissues confirm the previously described selectivity profiles of pirenzepine and AF-DX 116 in rat tissues. These findings thus reveal the presence also in man of three distinct muscarinic receptor subtypes: the neuronal M 1 , the cardiac M 2 and the glandular M 3

  5. Tissue engineering and surgery: from translational studies to human trials

    Directory of Open Access Journals (Sweden)

    Vranckx Jan Jeroen

    2017-06-01

    Full Text Available Tissue engineering was introduced as an innovative and promising field in the mid-1980s. The capacity of cells to migrate and proliferate in growth-inducing medium induced great expectancies on generating custom-shaped bioconstructs for tissue regeneration. Tissue engineering represents a unique multidisciplinary translational forum where the principles of biomaterial engineering, the molecular biology of cells and genes, and the clinical sciences of reconstruction would interact intensively through the combined efforts of scientists, engineers, and clinicians. The anticipated possibilities of cell engineering, matrix development, and growth factor therapies are extensive and would largely expand our clinical reconstructive armamentarium. Application of proangiogenic proteins may stimulate wound repair, restore avascular wound beds, or reverse hypoxia in flaps. Autologous cells procured from biopsies may generate an ‘autologous’ dermal and epidermal laminated cover on extensive burn wounds. Three-dimensional printing may generate ‘custom-made’ preshaped scaffolds – shaped as a nose, an ear, or a mandible – in which these cells can be seeded. The paucity of optimal donor tissues may be solved with off-the-shelf tissues using tissue engineering strategies. However, despite the expectations, the speed of translation of in vitro tissue engineering sciences into clinical reality is very slow due to the intrinsic complexity of human tissues. This review focuses on the transition from translational protocols towards current clinical applications of tissue engineering strategies in surgery.

  6. Combined spectroscopic imaging and chemometric approach for automatically partitioning tissue types in human prostate tissue biopsies

    Science.gov (United States)

    Haka, Abigail S.; Kidder, Linda H.; Lewis, E. Neil

    2001-07-01

    We have applied Fourier transform infrared (FTIR) spectroscopic imaging, coupling a mercury cadmium telluride (MCT) focal plane array detector (FPA) and a Michelson step scan interferometer, to the investigation of various states of malignant human prostate tissue. The MCT FPA used consists of 64x64 pixels, each 61 micrometers 2, and has a spectral range of 2-10.5 microns. Each imaging data set was collected at 16-1 resolution, resulting in 512 image planes and a total of 4096 interferograms. In this article we describe a method for separating different tissue types contained within FTIR spectroscopic imaging data sets of human prostate tissue biopsies. We present images, generated by the Fuzzy C-Means clustering algorithm, which demonstrate the successful partitioning of distinct tissue type domains. Additionally, analysis of differences in the centroid spectra corresponding to different tissue types provides an insight into their biochemical composition. Lastly, we demonstrate the ability to partition tissue type regions in a different data set using centroid spectra calculated from the original data set. This has implications for the use of the Fuzzy C-Means algorithm as an automated technique for the separation and examination of tissue domains in biopsy samples.

  7. Engineered human broncho-epithelial tissue-like assemblies

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    2012-01-01

    Three-dimensional human broncho-epithelial tissue-like assemblies (TLAs) are produced in a rotating wall vessel (RWV) with microcarriers by coculturing mesenchymal bronchial-tracheal cells (BTC) and bronchial epithelium cells (BEC). These TLAs display structural characteristics and express markers of in vivo respiratory epithelia. TLAs are useful for screening compounds active in lung tissues such as antiviral compounds, cystic fibrosis treatments, allergens, and cytotoxic compounds.

  8. The Human Tissue Act 2004 and the child donor.

    Science.gov (United States)

    Baston, Jenny

    2009-05-01

    In 2001, the inquiry panel appointed to investigate the removal, retention and disposal of human organs and tissues at the Royal Liverpool Children's Hospital published its report. The panel's recommendations led to a new approach to consent for organ removal and storage under the new Human Tissue Act 2004. For child bone marrow donors, the new consent process requires all donor children or their parent to undergo a separate assessment before the bone marrow donation. They must be assessed by an accredited assessor who will submit a recommendation to the Human Tissue Authority for consideration. The unfortunate circumstances highlighted in the inquiry have led to changes to law, practice and culture that are benefiting other children and families.

  9. Advancing biomaterials of human origin for tissue engineering

    Science.gov (United States)

    Chen, Fa-Ming; Liu, Xiaohua

    2015-01-01

    Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking inspiration from the role and multi-component construction of native extracellular matrices (ECMs) for cell accommodation, the synthetic biomaterials produced today routinely incorporate biologically active components to define an artificial in vivo milieu with complex and dynamic interactions that foster and regulate stem cells, similar to the events occurring in a natural cellular microenvironment. The range and degree of biomaterial sophistication have also dramatically increased as more knowledge has accumulated through materials science, matrix biology and tissue engineering. However, achieving clinical translation and commercial success requires regenerative biomaterials to be not only efficacious and safe but also cost-effective and convenient for use and production. Utilizing biomaterials of human origin as building blocks for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural tissue with regard to its physical and chemical properties for the orchestration of wound healing and tissue regeneration. In addition to directly using tissue transfers and transplants for repair, new applications of human-derived biomaterials are now focusing on the use of naturally occurring biomacromolecules, decellularized ECM scaffolds and autologous preparations rich in growth factors/non-expanded stem cells to either target acceleration/magnification of the body's own repair capacity or use nature's paradigms to create new tissues for

  10. Transepithelial Transport of PAMAM Dendrimers Across Isolated Human Intestinal Tissue.

    Science.gov (United States)

    Hubbard, Dallin; Enda, Michael; Bond, Tanner; Moghaddam, Seyyed Pouya Hadipour; Conarton, Josh; Scaife, Courtney; Volckmann, Eric; Ghandehari, Hamidreza

    2015-11-02

    Poly(amido amine) (PAMAM) dendrimers have shown transepithelial transport across intestinal epithelial barrier in rats and across Caco-2 cell monolayers. Caco-2 models innately lack mucous barriers, and rat isolated intestinal tissue has been shown to overestimate human permeability. This study is the first report of transport of PAMAM dendrimers across isolated human intestinal epithelium. It was observed that FITC labeled G4-NH2 and G3.5-COOH PAMAM dendrimers at 1 mM concentration do not have a statistically higher permeability compared to free FITC controls in isolated human jejunum and colonic tissues. Mannitol permeability was increased at 10 mM concentrations of G3.5-COOH and G4-NH2 dendrimers. Significant histological changes in human colonic and jejunal tissues were observed at G3.5-COOH and G4-NH2 concentrations of 10 mM implying that dose limiting toxicity may occur at similar concentrations in vivo. The permeability through human isolated intestinal tissue in this study was compared to previous rat and Caco-2 permeability data. This study implicates that PAMAM dendrimer oral drug delivery may be feasible, but it may be limited to highly potent drugs.

  11. Validation of the Maslach Burnout Inventory-Human Services Survey for Estimating Burnout in Dental Students.

    Science.gov (United States)

    Montiel-Company, José María; Subirats-Roig, Cristian; Flores-Martí, Pau; Bellot-Arcís, Carlos; Almerich-Silla, José Manuel

    2016-11-01

    The aim of this study was to examine the validity and reliability of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) as a tool for assessing the prevalence and level of burnout in dental students in Spanish universities. The survey was adapted from English to Spanish. A sample of 533 dental students from 15 Spanish universities and a control group of 188 medical students self-administered the survey online, using the Google Drive service. The test-retest reliability or reproducibility showed an Intraclass Correlation Coefficient of 0.95. The internal consistency of the survey was 0.922. Testing the construct validity showed two components with an eigenvalue greater than 1.5, which explained 51.2% of the total variance. Factor I (36.6% of the variance) comprised the items that estimated emotional exhaustion and depersonalization. Factor II (14.6% of the variance) contained the items that estimated personal accomplishment. The cut-off point for the existence of burnout achieved a sensitivity of 92.2%, a specificity of 92.1%, and an area under the curve of 0.96. Comparison of the total dental students sample and the control group of medical students showed significantly higher burnout levels for the dental students (50.3% vs. 40.4%). In this study, the MBI-HSS was found to be viable, valid, and reliable for measuring burnout in dental students. Since the study also found that the dental students suffered from high levels of this syndrome, these results suggest the need for preventive burnout control programs.

  12. A finite element evaluation of mechanical function for 3 distal extension partial dental prosthesis designs with a 3-dimensional nonlinear method for modeling soft tissue.

    Science.gov (United States)

    Nakamura, Yoshinori; Kanbara, Ryo; Ochiai, Kent T; Tanaka, Yoshinobu

    2014-10-01

    The mechanical evaluation of the function of partial removable dental prostheses with 3-dimensional finite element modeling requires the accurate assessment and incorporation of soft tissue behavior. The differential behaviors of the residual ridge mucosa and periodontal ligament tissues have been shown to exhibit nonlinear displacement. The mathematic incorporation of known values simulating nonlinear soft tissue behavior has not been investigated previously via 3-dimensional finite element modeling evaluation to demonstrate the effect of prosthesis design on the supporting tissues. The purpose of this comparative study was to evaluate the functional differences of 3 different partial removable dental prosthesis designs with 3-dimensional finite element analysis modeling and a simulated patient model incorporating known viscoelastic, nonlinear soft tissue properties. Three different designs of distal extension removable partial dental prostheses were analyzed. The stress distributions to the supporting abutments and soft tissue displacements of the designs tested were calculated and mechanically compared. Among the 3 dental designs evaluated, the RPI prosthesis demonstrated the lowest stress concentrations on the tissue supporting the tooth abutment and also provided wide mucosa-borne areas of support, thereby demonstrating a mechanical advantage and efficacy over the other designs evaluated. The data and results obtained from this study confirmed that the functional behavior of partial dental prostheses with supporting abutments and soft tissues are consistent with the conventional theories of design and clinical experience. The validity and usefulness of this testing method for future applications and testing protocols are shown. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  13. Formation of tissue factor activity following incubation of recombinant human tissue factor apoprotein with plasma lipoproteins

    International Nuclear Information System (INIS)

    Sakai, T.; Kisiel, W.

    1990-01-01

    Incubation of recombinant human tissue factor apoprotein (Apo-TF) with human plasma decreased the recalcified clotting time of this plasma in a time-and dose-dependent manner suggesting relipidation of the Apo-TF by plasma lipoproteins. Incubation of Apo-TF with purified preparations of human very low density, low density and high density lipoproteins resulted in tissue factor activity in a clotting assay. The order of effectiveness was VLDL greater than LDL much greater than HDL. Tissue factor activity generated by incubation of a fixed amount of Apo-TF with plasma lipoproteins was lipoprotein concentration-dependent and saturable. The association of Apo-TF with lipoprotein particles was supported by gel filtration studies in which 125 I-Apo-TF coeluted with the plasma lipoprotein in the void volume of a Superose 6 column in the presence and absence of calcium ions. In addition, void-volume Apo-TF-lipoprotein fractions exhibited tissue factor activity. These results suggest that the factor VIII-bypassing activity of bovine Apo-TF observed in a canine hemophilic model may be due, in part, to its association with plasma lipoproteins and expression of functional tissue factor activity

  14. Indirect immobilized Jagged1 suppresses cell cycle progression and induces odonto/osteogenic differentiation in human dental pulp cells.

    Science.gov (United States)

    Manokawinchoke, Jeeranan; Nattasit, Praphawi; Thongngam, Tanutchaporn; Pavasant, Prasit; Tompkins, Kevin A; Egusa, Hiroshi; Osathanon, Thanaphum

    2017-08-31

    Notch signaling regulates diverse biological processes in dental pulp tissue. The present study investigated the response of human dental pulp cells (hDPs) to the indirect immobilized Notch ligand Jagged1 in vitro. The indirect immobilized Jagged1 effectively activated Notch signaling in hDPs as confirmed by the upregulation of HES1 and HEY1 expression. Differential gene expression profiling using an RNA sequencing technique revealed that the indirect immobilized Jagged1 upregulated genes were mainly involved in extracellular matrix organization, disease, and signal transduction. Downregulated genes predominantly participated in the cell cycle, DNA replication, and DNA repair. Indirect immobilized Jagged1 significantly reduced cell proliferation, colony forming unit ability, and the number of cells in S phase. Jagged1 treated hDPs exhibited significantly higher ALP enzymatic activity, osteogenic marker gene expression, and mineralization compared with control. Pretreatment with a γ-secretase inhibitor attenuated the Jagged1-induced ALP activity and mineral deposition. NOTCH2 shRNA reduced the Jagged1-induced osteogenic marker gene expression, ALP enzymatic activity, and mineral deposition. In conclusion, indirect immobilized Jagged1 suppresses cell cycle progression and induces the odonto/osteogenic differentiation of hDPs via the canonical Notch signaling pathway.

  15. [Changes of dentin, dental pulp and periodontium tissue in tail-suspended rats].

    Science.gov (United States)

    Yuan, Lin-tian; Wen, Ling-ying; Luo, Ya-ning; Hu, Pei-zhen; Jiang, Wei-zhong; Wu, Xing-yu

    2003-08-01

    To investigate the metabolic changes of calcium and phosphorus in dentin, dental pulp and periodontium in tail-suspended rats, and the functions of TGF-beta 1, c-fos, collagen-I and collagen IV in dentin, dental pulp and periodontium. Relative percentage contents of Ca, P in dentin, dental pulp and periodontium were measured with scanning electron microscope and energy spectrum analytical system in 3 groups of rats. The expression of TGF-beta 1, c-fos, collagen-I and collagen IV were also observed. In the suspension group, the relative percentage content of Ca declined significantly, while P increased slightly. There were no significant differences of Ca, P in alveolar bone. The expressions of TGF-beta 1, c-fos and collagen-I declined, but the expression of collagen-IV in pulp vessel increased. There were no significant changes of expressions of TGF-beta 1, c-fos, collagen-I and collagen-IV in the vicinity of PDL. After adopting artificial countermeasures, the above expressions restored partly. Weightlessness might cause abnormal mineralization in dentin, and 1.5 G artificial countermeasures could eliminate the above changes of mineral metabolism. The poor mineralization of dentin might be associated with the reduced secretion of TGF-beta 1, c-fos and collagen-I in tail-suspended rats.

  16. Translational neuropharmacology: the use of human isolated gastrointestinal tissues.

    Science.gov (United States)

    Sanger, G J; Broad, J; Kung, V; Knowles, C H

    2013-01-01

    Translational sciences increasingly emphasize the measurement of functions in native human tissues. However, such studies must confront variations in patient age, gender, genetic background and disease. Here, these are discussed with reference to neuromuscular and neurosecretory functions of the human gastrointestinal (GI) tract. Tissues are obtained after informed consent, in collaboration with surgeons (surgical techniques help minimize variables) and pathologists. Given the difficulties of directly recording from human myenteric neurones (embedded between muscle layers), enteric motor nerve functions are studied by measuring muscle contractions/relaxations evoked by electrical stimulation of intrinsic nerves; responses are regionally dependent, often involving cholinergic and nitrergic phenotypes. Enteric sensory functions can be studied by evoking the peristaltic reflex, involving enteric sensory and motor nerves, but this has rarely been achieved. As submucosal neurones are more accessible (after removing the mucosa), direct neuronal recordings are possible. Neurosecretory functions are studied by measuring changes in short-circuit current across the mucosa. For all experiments, basic questions must be addressed. Because tissues are from patients, what are the controls and the influence of disease? How long does it take before function fully recovers? What is the impact of age- and gender-related differences? What is the optimal sample size? Addressing these and other questions minimizes variability and raises the scientific credibility of human tissue research. Such studies also reduce animal use. Further, the many differences between animal and human GI functions also means that human tissue research must question the ethical validity of using strains of animals with unproved translational significance. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  17. Tissue localization of human trefoil factors 1, 2, and 3

    DEFF Research Database (Denmark)

    Madsen, Jens; Nielsen, Ole; Tornøe, Ida

    2007-01-01

    Trefoil factors (TTFs) are small, compact proteins coexpressed with mucins in the gastrointestinal tract. Three trefoil factors are known in mammals: TFF1, TFF2, and TFF3. They are implicated to play diverse roles in maintenance and repair of the gastrointestinal channel. We compared the expression...... pattern of the three trefoil factors analyzing mRNA from a panel of 20 human tissues by conventional reverse transcriptase (RT) PCR and, in addition, by real-time PCR. These findings were supported by immunohistochemical analysis of paraffin-embedded human tissues using rabbit polyclonal antibodies raised...... against these factors. TFF1 showed highest expression in the stomach and colon, whereas TFF2 and TFF3 showed highest expression in stomach and colon, respectively. All three TFFs were found in the ducts of pancreas. Whereas TFF2 was found to be restricted to these two tissues, the structurally more...

  18. Tissue distribution of human acetylcholinesterase and butyrylcholinesterase messenger RNA

    Energy Technology Data Exchange (ETDEWEB)

    Jbilo, O.; Barteles, C.F.; Chatonnet, A.; Toutant, J.P.; Lockridge, O.

    1994-12-31

    Tissue distribution of human acetyicholinesterase and butyryicholinesterase messenger RNA. 1 Cholinesterase inhibitors occur naturally in the calabar bean (eserine), green potatoes (solanine), insect-resistant crab apples, the coca plant (cocaine) and snake venom (fasciculin). There are also synthetic cholinesterase inhibitors, for example man-made insecticides. These inhibitors inactivate acetyicholinesterase and butyrylcholinesterase as well as other targets. From a study of the tissue distribution of acetylcholinesterase and butyrylcholinesterase mRNA by Northern blot analysis, we have found the highest levels of butyrylcholinesterase mRNA in the liver and lungs, tissues known as the principal detoxication sites of the human body. These results indicate that butyrylcholinesterase may be a first line of defense against poisons that are eaten or inhaled.

  19. Infrared absorption of human breast tissues in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Liu Chenglin [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Physics Department of Yancheng Teachers' College, Yancheng 224002 (China); Zhang Yuan [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Yan Xiaohui [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Zhang Xinyi [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China) and Shanghai Research Center of Acupuncture and Meridian, Pudong, Shanghai 201203 (China)]. E-mail: xy-zhang@fudan.edu.cn; Li Chengxiang [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Yang Wentao [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China); Shi Daren [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China)

    2006-07-15

    The spectral characteristics of human breast tissues in normal status and during different cancerous stages have been investigated by synchrotron radiation based Fourier transform infrared (SR-FTIR) absorption spectroscopy. Thanks to the excellent synchrotron radiation infrared (IR) source, higher resolving power is achieved in SR-FTIR absorption spectra than in conventional IR absorption measurements. Obvious variations in IR absorption spectrum of breast tissues were found as they change from healthy to diseased, or say in progression to cancer. On the other hand, some specific absorption peaks were found in breast cancer tissues by SR-FTIR spectroscopic methods. These spectral characteristics of breast tissue may help us in early diagnosis of breast cancer.

  20. Analysis of human skin tissue by millimeter-wave reflectometry

    NARCIS (Netherlands)

    Smulders, P.F.M.

    2013-01-01

    Background/pupose: Millimeter-wave reflectometry is a potentially interesting technique to analyze the human skin in vivo in order to determine the water content locally in the skin. Purpose of this work is to investigate the possibility of skin-tissue differentiation. In addition, it addresses the

  1. Human Bites of the Face with Tissue Losses in Cosmopolitan ...

    African Journals Online (AJOL)

    Dr. Milaki Asuku

    A retrospective series of thirty-six cases of human bites to the face with tissue losses requiring reconstruction ..... bite wounds when compared to other forms of trauma in our regional ... References. 1. Liston PN, Tong DC, Firth NA, Kieser JA.

  2. Human meniscal proteoglycan metabolism in long-term tissue culture

    NARCIS (Netherlands)

    Verbruggen, G.; Verdonk, R.; Veys, E. M.; van Daele, P.; de Smet, P.; van den Abbeele, K.; Claus, B.; Baeten, D.

    1996-01-01

    For the purpose of human meniscal allografting, menisci have been maintained viable in in vitro culture. The influence of long-term tissue culture on the extracellular matrix metabolism of the meniscus has been studied. Fetal calf serum (FCS) was used as a supplement for the growth factors necessary

  3. Assessment of permeation of lipoproteins in human carotid tissue

    Science.gov (United States)

    Ghosn, Mohamad G.; Syed, Saba H.; Leba, Michael; Morrisett, Joel D.; Tuchin, Valery V.; Larin, Kirill V.

    2010-02-01

    Cardiovascular disease is among the leading causes of death in the United States. Specifically, atherosclerosis is an increasingly devastating contributor to the tally and has been found to be a byproduct of arterial permeability irregularities in regards to lipoprotein penetration. To further explore arterial physiology and molecular transport, the imaging technique of Optical Coherence Tomography (OCT) was employed. With OCT, the permeation of glucose (MW = 180 Da), low density lipoprotein (LDL; MW = 2.1 × 106 Da), and high density lipoprotein (HDL; MW = 2.5 × 105 Da) in human carotid tissue was studied to determine the effect of different molecular characteristics on permeation in atherosclerotic tissues. The permeability rates calculated from the diffusion of the molecular agents into the abnormal carotid tissue samples is compared to those of normal, healthy tissue. The results show that in the abnormal tissue, the permeation of agents correlate to the size constraints. The larger molecules of LDL diffuse the slowest, while the smallest molecules of glucose diffuse the fastest. However, in normal tissue, LDL permeates at a faster rate than the other two agents, implying the existence of a transport mechanism that facilitates the passage of LDL molecules. These results highlight the capability of OCT as a sensitive and specific imaging technique as well as provide significant information to the understanding of atherosclerosis and its effect on tissue properties.

  4. Tissue

    Directory of Open Access Journals (Sweden)

    David Morrissey

    2012-01-01

    Full Text Available Purpose. In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. Methods. Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. Results. In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. Conclusions. Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.

  5. Mineral density volume gradients in normal and diseased human tissues.

    Directory of Open Access Journals (Sweden)

    Sabra I Djomehri

    Full Text Available Clinical computed tomography provides a single mineral density (MD value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca to phosphorus (P and Ca to zinc (Zn elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males contained significant mineral density variations (enamel: 2820-3095 mg/cc, bone: 570-1415 mg/cc, cementum: 1240-1340 mg/cc, dentin: 1480-1590 mg/cc, cementum affected by periodontitis: 1100-1220 mg/cc, hypomineralized carious dentin: 345-1450 mg/cc, hypermineralized carious dentin: 1815-2740 mg/cc, and dental calculus: 1290-1770 mg/cc. A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49, hypomineralized dentin (0.32-0.46, cementum (1.51, and bone (1.68 were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765 and in cementum (595-990, highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations.

  6. Mineral Density Volume Gradients in Normal and Diseased Human Tissues

    Science.gov (United States)

    Djomehri, Sabra I.; Candell, Susan; Case, Thomas; Browning, Alyssa; Marshall, Grayson W.; Yun, Wenbing; Lau, S. H.; Webb, Samuel; Ho, Sunita P.

    2015-01-01

    Clinical computed tomography provides a single mineral density (MD) value for heterogeneous calcified tissues containing early and late stage pathologic formations. The novel aspect of this study is that, it extends current quantitative methods of mapping mineral density gradients to three dimensions, discretizes early and late mineralized stages, identifies elemental distribution in discretized volumes, and correlates measured MD with respective calcium (Ca) to phosphorus (P) and Ca to zinc (Zn) elemental ratios. To accomplish this, MD variations identified using polychromatic radiation from a high resolution micro-computed tomography (micro-CT) benchtop unit were correlated with elemental mapping obtained from a microprobe X-ray fluorescence (XRF) using synchrotron monochromatic radiation. Digital segmentation of tomograms from normal and diseased tissues (N=5 per group; 40-60 year old males) contained significant mineral density variations (enamel: 2820-3095mg/cc, bone: 570-1415mg/cc, cementum: 1240-1340mg/cc, dentin: 1480-1590mg/cc, cementum affected by periodontitis: 1100-1220mg/cc, hypomineralized carious dentin: 345-1450mg/cc, hypermineralized carious dentin: 1815-2740mg/cc, and dental calculus: 1290-1770mg/cc). A plausible linear correlation between segmented MD volumes and elemental ratios within these volumes was established, and Ca/P ratios for dentin (1.49), hypomineralized dentin (0.32-0.46), cementum (1.51), and bone (1.68) were observed. Furthermore, varying Ca/Zn ratios were distinguished in adapted compared to normal tissues, such as in bone (855-2765) and in cementum (595-990), highlighting Zn as an influential element in prompting observed adaptive properties. Hence, results provide insights on mineral density gradients with elemental concentrations and elemental footprints that in turn could aid in elucidating mechanistic processes for pathologic formations. PMID:25856386

  7. The prevalence, pattern and clinical presentation of developmental dental hard-tissue anomalies in children with primary and mix dentition from Ile-Ife, Nigeria.

    Science.gov (United States)

    Temilola, Dada Oluwaseyi; Folayan, Morenike Oluwatoyin; Fatusi, Olawunmi; Chukwumah, Nneka Maureen; Onyejaka, Nneka; Oziegbe, Elizabeth; Oyedele, Titus; Kolawole, Kikelomo Adebanke; Agbaje, Hakeem

    2014-10-16

    The study of dental anomalies is important because it generates information that is important for both the anthropological and clinical management of patients. The objective of this study is to determine the prevalence and pattern of presentation of dental hard-tissue developmental anomalies in the mix dentition of children residing in Ile-Ife, a suburban region of Nigeria. Information on age, sex and socioeconomic status was collected from 1,036 children aged four months to 12 years through a household survey. Clinical examination was conducted to assess the presence of dental anomalies. Associations between age, sex, socioeconomic status, prevalence, and pattern of presentation of the developmental hard-tissue dental anomalies were determined. Two hundred and seventy six (26.6%) children had dental anomalies. Of these, 23.8% had one anomaly, 2.5% had two anomalies, and 0.3% had more than two anomalies. Of the children with anomalies, 49.3%were male, 50.7%were female, and 47.8%, 28.6% and 23.6% were children from low, middle and high socioeconomic classes, respectively. More anomalies were seen in permanent than primary dentition. Anomalies of tooth structure were most prevalent (16.1%); anomalies which affect tooth number were least prevalent (1.3%). Dens evaginatus, peg-shaped lateral, macrodontia, and talon cusp were more prevalent in the permanent dentition, and dens evaginatus peg-shaped lateral and macrodontia were more prevalent in the maxilla. There were significantly more macrodontia anomalies in males and in children of high socioeconomic status. This large survey of dental hard-tissue anomalies found in the primary dentition and mixed dentition of children in Nigeria provides anthropological and clinical data that may aid the detection and management of dental problems of children in Nigeria.

  8. Dental Fluorosis and Catalase Immunoreactivity of the Brain Tissues in Rats Exposed to High Fluoride Pre- and Postnatally.

    Science.gov (United States)

    Güner, Şirin; Uyar-Bozkurt, Süheyla; Haznedaroğlu, Eda; Menteş, Ali

    2016-11-01

    This study evaluated dental fluorosis of the incisors and immunoreactivity in the brain tissues of rats given chronic fluoride doses pre- and postnatally. Female rats were given drinking water with 0, 30 or 100 ppm fluoride ad libitum throughout gestation and the nursing period. In addition, 63 male offspring were treated with the same water regimens as the mothers after weaning and were followed for 1, 3 or 5 months. The upper and lower incisors were collected, and all teeth were examined under a stereomicroscope and scored by two blinded examiners using a modified rodent enamel fluorosis index. Cortical, hippocampal and cerebellar brain samples were evaluated morphologically and immunohistochemically. All fluoride-treated pups were born with low body weight (p = 0.001). All animals from the fluoride groups had enamel fluorosis with defects of various degrees. The increase in the dental fluorosis scores in the fluoride treatment groups was significant (p fluoride groups was significantly higher than that in the controls after 1, 3 and 5 months (p toxicity of fluoride.

  9. Scanning electron microscopy and electron probe microanalyses of the crystalline components of human and animal dental calculi

    International Nuclear Information System (INIS)

    LeGeros, R.Z.; Orly, I.; LeGeros, J.P.; Gomez, C.; Kazimiroff, J.; Tarpley, T.; Kerebel, B.

    1988-01-01

    A review of the use of scanning electron microscopy (SEM) and electron probe microanalyses in the study of dental calculus showed that such studies provided confirmatory and supplementary data on the morphological features of human dental calculi but gave only limited information on the identity of the crystalline or inorganic components. This study aimed to explore the potential of combined SEM and microanalyses in the identification of the crystalline components of the human and animal dental calculi. Human and animal calculi were analyzed. Identification of the crystalline components were made based on the combined information of the morphology (SEM) and Ca/P molar ratios of the crystals with the morphology and Ca/P molar ratio of synthetic calcium phosphates (brushite or DCPD; octacalcium phosphate, OCP; Mg-substituted whitlockite, beta-TCMP; CO 3 -substituted apatite, (CHA); and calcite. SEM showed similarities in morphological features of human and animal dental calculi but differences in the forms of crystals present. Microanalyses and crystal morphology data suggested the presence of CaCO 3 (calcite) and CHA in the animal (cat, dog, tiger) and of OCP, beta-TCMP and CHA in human dental calculi. X-ray diffraction and infrared (IR) absorption analyses confirmed these results. This exploratory study demonstrated that by taking into consideration what is known about the crystalline components of human and animal dental calculi, combined SEM and microanalyses can provide qualitative identification

  10. Zicam-induced damage to mouse and human nasal tissue.

    Directory of Open Access Journals (Sweden)

    Jae H Lim

    Full Text Available Intranasal medications are used to treat various nasal disorders. However, their effects on olfaction remain unknown. Zicam (zinc gluconate; Matrixx Initiatives, Inc, a homeopathic substance marketed to alleviate cold symptoms, has been implicated in olfactory dysfunction. Here, we investigated Zicam and several common intranasal agents for their effects on olfactory function. Zicam was the only substance that showed significant cytotoxicity in both mouse and human nasal tissue. Specifically, Zicam-treated mice had disrupted sensitivity of olfactory sensory neurons to odorant stimulation and were unable to detect novel odorants in behavioral testing. These findings were long-term as no recovery of function was observed after two months. Finally, human nasal explants treated with Zicam displayed significantly elevated extracellular lactate dehydrogenase levels compared to saline-treated controls, suggesting severe necrosis that was confirmed on histology. Our results demonstrate that Zicam use could irreversibly damage mouse and human nasal tissue and may lead to significant smell dysfunction.

  11. Guided tissue regeneration ensures osseointegration of dental implants placed into extraction sockets. An experimental study in monkeys

    DEFF Research Database (Denmark)

    Warrer, L; Gotfredsen, K; Hjørting-Hansen, E

    1991-01-01

    on the buccal and palatal aspects of the maxillary molars in both sides of the jaw. The second molars were then extracted and self tapping titanium implants of the screw type (Astra Dental Implants) were inserted into the sockets of the largest roots. In the coronal portion of the sockets, a void was always...... present between the implant and the socket walls. In one side of the jaw, a membrane (Gore-Tex Augmentation Material) was adjusted to cover the implant. The implant in the other side of the jaw served as control and was only covered by the tissue flaps. Microscopic analysis after 3 months of healing...... technique can secure complete osseointegration of implants inserted immediately into extraction sockets....

  12. Occurrence of human bocaviruses and parvovirus 4 in solid tissues.

    Science.gov (United States)

    Norja, Päivi; Hedman, Lea; Kantola, Kalle; Kemppainen, Kaisa; Suvilehto, Jari; Pitkäranta, Anne; Aaltonen, Leena-Maija; Seppänen, Mikko; Hedman, Klaus; Söderlund-Venermo, Maria

    2012-08-01

    Human bocaviruses 1-4 (HBoV1-4) and parvovirus 4 (PARV4) are recently discovered human parvoviruses. HBoV1 is associated with respiratory infections of young children, while HBoV2-4 are enteric viruses. The clinical manifestations of PARV4 remain unknown. The objective of this study was to determine whether the DNAs of HBoV1-4 and PARV4 persist in human tissues long after primary infection. Biopsies of tonsillar tissue, skin, and synovia were examined for HBoV1-4 DNA and PARV4 DNA by PCR. Serum samples from the tissue donors were assayed for HBoV1 and PARV4 IgG and IgM antibodies. To obtain species-specific seroprevalences for HBoV1 and for HBoV2/3 combined, the sera were analyzed after virus-like particle (VLP) competition. While HBoV1 DNA was detected exclusively in the tonsillar tissues of 16/438 individuals (3.7%), all of them ≤8 years of age. HBoV2-4 and PARV4 DNAs were absent from all tissue types. HBoV1 IgG seroprevalence was 94.9%. No subject had HBoV1 or PARV4 IgM, nor did they have PARV4 IgG. The results indicate that HBoV1 DNA occurred in a small proportion of tonsils of young children after recent primary HBoV1 infection, but did not persist long in the other tissue types studied, unlike parvovirus B19 DNA. The results obtained by the PARV4 assays are in line with previous results on PARV4 epidemiology. Copyright © 2012 Wiley Periodicals, Inc.

  13. Immunolocalisation of oestrogen receptor beta in human tissues.

    Science.gov (United States)

    Taylor, A H; Al-Azzawi, F

    2000-02-01

    Oestrogens exert their actions via specific nuclear protein receptors that are members of the steroid/thyroid receptor superfamily of transcription factors. Recently, a second oestrogen receptor (ERbeta) has been cloned, and using reverse transcription-PCR and immunohistochemistry it has been shown to have a wide tissue distribution in the rat that is distinct from the classical oestrogen receptor, ERalpha. Using commercial polyclonal antisera against peptides specific to human ERbeta, we have determined the sites of ERbeta expression in archival and formalin-fixed human tissue and compared its expression with that of ERalpha. ERbeta was localised to the cell nuclei of a wide range of normal adult human tissues including ovary, Fallopian tube, uterus, lung, kidney, brain, heart, prostate and testis. In the ovary, ERbeta was present in multiple cell types including granulosa cells in small, medium and large follicles, theca and corpora lutea, whereas ERalpha was weakly expressed in the nuclei of granulosa cells, but not in the theca nor in the copora lutea. In the endometrium, both ERalpha and ERbeta were observed in luminal epithelial cells and in the nuclei of stromal cells but, significantly, ERbeta was weak or absent from endometrial glandular epithelia. Epithelial cells in most male tissues including the prostate, the urothelium and muscle layers of the bladder, and Sertoli cells in the testis, were also immunopositive for ERbeta. Significant ERbeta immunoreactivity was detected in most areas of the brain, with the exception of the hippocampus - a tissue that stained positively for ERalpha. In conclusion, the almost ubiquitous immunohistochemical localisation of ERbeta indicates that ERbeta may play a major role in the mediation of oestrogen action. The differential expression of ERalpha and ERbeta in some of these tissues suggests a more complex control mechanism in oestrogenic potential than originally envisioned.

  14. Usherin expression is highly conserved in mouse and human tissues.

    Science.gov (United States)

    Pearsall, Nicole; Bhattacharya, Gautam; Wisecarver, Jim; Adams, Joe; Cosgrove, Dominic; Kimberling, William

    2002-12-01

    Usher syndrome is an autosomal recessive disease that results in varying degrees of hearing loss and retinitis pigmentosa. Three types of Usher syndrome (I, II, and III) have been identified clinically with Usher type II being the most common of the three types. Usher type II has been localized to three different chromosomes 1q41, 3p, and 5q, corresponding to Usher type 2A, 2B, and 2C respectively. Usherin is a basement membrane protein encoded by the USH2A gene. Expression of usherin has been localized in the basement membrane of several tissues, however it is not ubiquitous. Immunohistochemistry detected usherin in the following human tissues: retina, cochlea, small and large intestine, pancreas, bladder, prostate, esophagus, trachea, thymus, salivary glands, placenta, ovary, fallopian tube, uterus, and testis. Usherin was absent in many other tissues such as heart, lung, liver, kidney, and brain. This distribution is consistent with the usherin distribution seen in the mouse. Conservation of usherin is also seen at the nucleotide and amino acid level when comparing the mouse and human gene sequences. Evolutionary conservation of usherin expression at the molecular level and in tissues unaffected by Usher 2a supports the important structural and functional role this protein plays in the human. In addition, we believe that these results could lead to a diagnostic procedure for the detection of Usher syndrome and those who carry an USH2A mutation.

  15. Protein Kinase A Regulatory Subunits in Human Adipose Tissue

    Science.gov (United States)

    Mantovani, Giovanna; Bondioni, Sara; Alberti, Luisella; Gilardini, Luisa; Invitti, Cecilia; Corbetta, Sabrina; Zappa, Marco A.; Ferrero, Stefano; Lania, Andrea G.; Bosari, Silvano; Beck-Peccoz, Paolo; Spada, Anna

    2009-01-01

    OBJECTIVE—In human adipocytes, the cAMP-dependent pathway mediates signals originating from β-adrenergic activation, thus playing a key role in the regulation of important metabolic processes, i.e., lipolysis and thermogenesis. Cyclic AMP effects are mainly mediated by protein kinase A (PKA), whose R2B regulatory isoform is the most expressed in mouse adipose tissue, where it protects against diet-induced obesity and fatty liver development. The aim of the study was to investigate possible differences in R2B expression, PKA activity, and lipolysis in adipose tissues from obese and nonobese subjects. RESEARCH DESIGN AND METHODS—The expression of the different PKA regulatory subunits was evaluated by immunohistochemistry, Western blot, and real-time PCR in subcutaneous and visceral adipose tissue samples from 20 nonobese and 67 obese patients. PKA activity and glycerol release were evaluated in total protein extract and adipocytes isolated from fresh tissue samples, respectively. RESULTS—Expression techniques showed that R2B was the most abundant regulatory protein, both at mRNA and protein level. Interestingly, R2B mRNA levels were significantly lower in both subcutaneous and visceral adipose tissues from obese than nonobese patients and negatively correlated with BMI, waist circumference, insulin levels, and homeostasis model assessment of insulin resistance. Moreover, both basal and stimulated PKA activity and glycerol release were significantly lower in visceral adipose tissue from obese patients then nonobese subjects. CONCLUSIONS—Our results first indicate that, in human adipose tissue, there are important BMI-related differences in R2B expression and PKA activation, which might be included among the multiple determinants involved in the different lipolytic response to β-adrenergic activation in obesity. PMID:19095761

  16. Acids with an equivalent taste lead to different erosion of human dental enamel.

    Science.gov (United States)

    Beyer, Markus; Reichert, Jörg; Bossert, Jörg; Sigusch, Bernd W; Watts, David C; Jandt, Klaus D

    2011-10-01

    The consumption of acidic soft drinks may lead to demineralization and softening of human dental enamel, known as dental erosion. The aims of this in vitro study were to determine: (i) if different acids with a similar sensorial acidic taste lead to different hardness loss of enamel and (ii) if the fruit acids tartaric, malic, lactic or ascorbic acid lead to less hardness loss of enamel than citric or phosphoric acid when their concentration in solution is based on an equivalent sensorial acidic taste. Enamel samples of non-erupted human third molars were treated with acidic solutions of tartaric (TA), malic (MA), lactic (LA), ascorbic (AA), phosphoric (PA) and citric (CA) acids with a concentration that gave an equivalent sensorial acidic taste. The acidic solutions were characterized by pH value and titratable acidity. Atomic force microscopy (AFM) based nanoindentation was used to study the nano mechanical properties and scanning electron microscopy (SEM) was used to study the morphology of the treated enamel samples and the untreated control areas, respectively. The investigated acids fell into two groups. The nano hardnesses of MA, TA and CA treated enamel samples (group I) were statistically significantly greater (penamel samples (group II). Within each group the nano hardness was not statistically significantly different (p>0.05). The SEM micrographs showed different etch prism morphologies depending on the acid used. In vitro, the acids investigated led to different erosion effects on human dental enamel, despite their equivalent sensorial acidic taste. This has not been reported previously. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  17. Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

    International Nuclear Information System (INIS)

    Silva, A.L.M.; Figueroa, R.; Jaramillo, A.; Carvalho, M.L.; Veloso, J.F.C.A.

    2013-01-01

    Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm 2 presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues

  18. Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.L.M. [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal); Figueroa, R.; Jaramillo, A. [Physics Department, Universidad de La Frontera, Temuco (Chile); Carvalho, M.L. [Atomic Physics Centre, University of Lisbon, 1649-03 Lisboa (Portugal); Veloso, J.F.C.A., E-mail: joao.veloso@ua.pt [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal)

    2013-08-01

    Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm{sup 2} presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues.

  19. Human dental pulp pluripotent-like stem cells promote wound healing and muscle regeneration.

    Science.gov (United States)

    Martínez-Sarrà, Ester; Montori, Sheyla; Gil-Recio, Carlos; Núñez-Toldrà, Raquel; Costamagna, Domiziana; Rotini, Alessio; Atari, Maher; Luttun, Aernout; Sampaolesi, Maurilio

    2017-07-27

    Dental pulp represents an easily accessible autologous source of adult stem cells. A subset of these cells, named dental pulp pluripotent-like stem cells (DPPSC), shows high plasticity and can undergo multiple population doublings, making DPPSC an appealing tool for tissue repair or maintenance. DPPSC were harvested from the dental pulp of third molars extracted from young patients. Growth factors released by DPPSC were analysed using antibody arrays. Cells were cultured in specific differentiation media and their endothelial, smooth and skeletal muscle differentiation potential was evaluated. The therapeutic potential of DPPSC was tested in a wound healing mouse model and in two genetic mouse models of muscular dystrophy (Scid/mdx and Sgcb-null Rag2-null γc-null). DPPSC secreted several growth factors involved in angiogenesis and extracellular matrix deposition and improved vascularisation in all three murine models. Moreover, DPPSC stimulated re-epithelialisation and ameliorated collagen deposition and organisation in healing wounds. In dystrophic mice, DPPSC engrafted in the skeletal muscle of both dystrophic murine models and showed integration in muscular fibres and vessels. In addition, DPPSC treatment resulted in reduced fibrosis and collagen content, larger cross-sectional area of type II fast-glycolytic fibres and infiltration of higher numbers of proangiogenic CD206 + macrophages. Overall, DPPSC represent a potential source of stem cells to enhance the wound healing process and slow down dystrophic muscle degeneration.

  20. Dental Calculus Arrest of Dental Caries.

    Science.gov (United States)

    Keyes, Paul H; Rams, Thomas E

    An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. These observations further document the potential protective effects of dental calculus mineralization against dental caries.

  1. Dental Calculus Arrest of Dental Caries

    Science.gov (United States)

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  2. The synthetic human beta-defensin-3 C15 peptide exhibits antimicrobial activity against Streptococcus mutans, both alone and in combination with dental disinfectants.

    Science.gov (United States)

    Ahn, Ki Bum; Kim, A Reum; Kum, Kee-Yeon; Yun, Cheol-Heui; Han, Seung Hyun

    2017-10-01

    Streptococcus mutans is a major etiologic agent of human dental caries that forms biofilms on hard tissues in the human oral cavity, such as tooth and dentinal surfaces. Human β-defensin-3 (HBD3) is a 45-amino-acid natural antimicrobial peptide that has broad spectrum antimicrobial activity against bacteria and fungi. A synthetic peptide consisting of the C-terminal 15 amino acids of HBD3 (HBD3-C15) was recently shown to be sufficient for its antimicrobial activity. Thus, clinical applications of this peptide have garnered attention. In this study, we investigated whether HBD3-C15 inhibits the growth of the representative cariogenic pathogen Streptococcus mutans and its biofilm formation. HBD3-C15 inhibited bacterial growth, exhibited bactericidal activity, and attenuated bacterial biofilm formation in a dose-dependent manner. HBD3-C15 potentiated the bactericidal and anti-biofilm activity of calcium hydroxide (CH) and chlorhexidine digluconate (CHX), which are representative disinfectants used in dental clinics, against S. mutans. Moreover, HBD3-C15 showed antimicrobial activity by inhibiting biofilm formation by S. mutans and other dentinophilic bacteria such as Enterococcus faecalis and Streptococcus gordonii, which are associated with dental caries and endodontic infection, on human dentin slices. These effects were observed for HBD3-C15 alone and for HBD3-C15 in combination with CH or CHX. Therefore, we suggest that HBD3-C15 is a potential alternative or additive disinfectant that can be used for the treatment of oral infectious diseases, including dental caries and endodontic infections.

  3. Human dental pulp stem cells cultured in serum-free supplemented medium

    Directory of Open Access Journals (Sweden)

    Virginie eBonnamain

    2013-12-01

    Full Text Available Growing evidence show that human dental pulp stem cells (DPSCs could provide a source of adult stem cells for the treatment of neurodegenerative pathologies. In this study, DPSCs were expanded and cultured with a protocol generally used for the culture of neural stem/progenitor cells.Methodology: DPSC cultures were established from third molars. The pulp tissue was enzymatically digested and cultured in serum-supplemented basal medium for 12 hours. Adherent (ADH and non-adherent (non-ADH cell populations were separated according to their differential adhesion to plastic and then cultured in serum-free defined N2 medium with epidermal growth factor (EGF and basic fibroblast growth factor (bFGF. Both ADH and non-ADH populations were analyzed by FACS and/or PCR.Results: FACS analysis of ADH-DPSCs revealed the expression of the mesenchymal cell marker CD90, the neuronal marker CD56, the transferrin receptor CD71, and the chemokine receptor CXCR3, whereas hematopoietic stem cells markers CD45, CD133 and CD34 were not expressed. ADH-DPSCs expressed transcripts coding for the Nestin gene, whereas expression levels of genes coding for the neuronal markers β-III tubulin and NF-M, and the oligodendrocyte marker PLP-1 were donor dependent. ADH-DPSCs did not express the transcripts for GFAP, an astrocyte marker. Cells of the non-ADH population that grew as spheroids expressed Nestin, β-III tubulin, NF-M and PLP-1 transcripts. DPSCs migrated out of the spheroids exhibited an odontoblast-like morphology and expressed a higher level of DSPP and osteocalcin transcripts than ADH-DPSCs. Conclusion: Collectively, these data indicate that human DPSCs can be expended and cultured in serum-free supplemented medium with EGF and bFGF. ADH-DPSCs and non-ADH populations contained neuronal and/or oligodendrocyte precursors at different stages of commitment and interestingly, cells from spheroid structures seem to be more engaged into the odontoblastic lineage than the

  4. Utilization of radiometric method in evaluation of wear on human dental enamel in vitro by dental porcelain glazed and polished

    International Nuclear Information System (INIS)

    Adachi, Lena Katekawa; Campos, Tomie Nakakuki de; Adachi, Eduardo Makoto

    2005-01-01

    The dental porcelain is a material commonly used in prosthesis. Disadvantages of dental porcelain use include possibility to cause tooth or dental materials wear. Before its use in the mouth, surfaces are treated with polishing and/or glazing. This research used the radiometric method to verify the influence of these surface treatments on the porcelains of commercial brands: Ceramco II, Noritake and Finesse. This method was originally developed for dentifrice abrasiveness evaluation. Five specimens of dental enamel and 10 specimens of each porcelain (5 glazed, 5 polished) were used. The dental enamel was flattened and irradiated with neutrons from the IEA-R1 (IPEN/CNEN) nuclear reactor. Then it was weared by each porcelain in sliding motion, with water. After 2,500 cycles for each porcelain specimen, the released enamel residue was measured. The enamel wear was evaluated by measuring beta activity of 32 P transferred to water from the irradiated tooth. Results varied from 2.57 to 5.81 μg of enamel /mm 2 weared surface. There was no statistical difference (α=0.05) between dental enamel wear caused by the same porcelains glazed or polished. The results suggest that adequate surface finishing depend on the type of dental porcelain. (author)

  5. In vivo imaging of human oral hard and soft tissues by polarization-sensitive optical coherence tomography

    Science.gov (United States)

    Walther, Julia; Golde, Jonas; Kirsten, Lars; Tetschke, Florian; Hempel, Franz; Rosenauer, Tobias; Hannig, Christian; Koch, Edmund

    2017-12-01

    Since optical coherence tomography (OCT) provides three-dimensional high-resolution images of biological tissue, the benefit of polarization contrast in the field of dentistry is highlighted in this study. Polarization-sensitive OCT (PS OCT) with phase-sensitive recording is used for imaging dental and mucosal tissues in the human oral cavity in vivo. An enhanced polarization contrast of oral structures is reached by analyzing the signals of the co- and crosspolarized channels of the swept source PS OCT system quantitatively with respect to reflectivity, retardation, optic axis orientation, and depolarization. The calculation of these polarization parameters enables a high tissue-specific contrast imaging for the detailed physical interpretation of human oral hard and soft tissues. For the proof-of-principle, imaging of composite restorations and mineralization defects at premolars as well as gingival, lingual, and labial oral mucosa was performed in vivo within the anterior oral cavity. The achieved contrast-enhanced results of the investigated human oral tissues by means of polarization-sensitive imaging are evaluated by the comparison with conventional intensity-based OCT.

  6. Alcohol Inhibits Odontogenic Differentiation of Human Dental Pulp Cells by Activating mTOR Signaling

    Directory of Open Access Journals (Sweden)

    Wei Qin

    2017-01-01

    Full Text Available Long-term heavy alcohol consumption could result in a range of health, social, and behavioral problems. People who abuse alcohol are at high risks of seriously having osteopenia, periodontal disease, and compromised oral health. However, the role of ethanol (EtOH in the biological functions of human dental pulp cells (DPCs is unknown. Whether EtOH affects the odontoblastic differentiation of DPCs through the mechanistic target of rapamycin (mTOR remains unexplored. The objective of this study was to investigate the effects of EtOH on DPC differentiation and mineralization. DPCs were isolated and purified from human dental pulps. The proliferation and odontoblastic differentiation of DPCs treated with EtOH were subsequently investigated. Different doses of EtOH were shown to be cytocompatible with DPCs. EtOH significantly activated the mTOR pathway in a dose-dependent manner. In addition, EtOH downregulated the alkaline phosphatase activity, attenuated the mineralized nodule formation, and suppressed the expression of odontoblastic markers including ALP, DSPP, DMP-1, Runx2, and OCN. Moreover, the pretreatment with rapamycin, a specific mTOR inhibitor, markedly reversed the EtOH-induced odontoblastic differentiation and cell mineralization. Our findings show for the first time that EtOH can suppress DPC differentiation and mineralization in a mTOR-dependent manner, indicating that EtOH may be involved in negatively regulating the dental pulp repair.

  7. Analysis of gene expression during odontogenic differentiation of cultured human dental pulp cells

    Directory of Open Access Journals (Sweden)

    Min-Seock Seo

    2012-08-01

    Full Text Available Objectives We analyzed gene-expression profiles after 14 day odontogenic induction of human dental pulp cells (DPCs using a DNA microarray and sought candidate genes possibly associated with mineralization. Materials and Methods Induced human dental pulp cells were obtained by culturing DPCs in odontogenic induction medium (OM for 14 day. Cells exposed to normal culture medium were used as controls. Total RNA was extracted from cells and analyzed by microarray analysis and the key results were confirmed selectively by reverse-transcriptase polymerase chain reaction (RT-PCR. We also performed a gene set enrichment analysis (GSEA of the microarray data. Results Six hundred and five genes among the 47,320 probes on the BeadChip differed by a factor of more than two-fold in the induced cells. Of these, 217 genes were upregulated, and 388 were down-regulated. GSEA revealed that in the induced cells, genes implicated in Apoptosis and Signaling by wingless MMTV integration (Wnt were significantly upregulated. Conclusions Genes implicated in Apoptosis and Signaling by Wnt are highly connected to the differentiation of dental pulp cells into odontoblast.

  8. A Case Study Optimizing Human Resources in Rwanda's First Dental School: Three Innovative Management Tools.

    Science.gov (United States)

    Hackley, Donna M; Mumena, Chrispinus H; Gatarayiha, Agnes; Cancedda, Corrado; Barrow, Jane R

    2018-06-01

    Harvard School of Dental Medicine, University of Maryland School of Dentistry, and the University of Rwanda (UR) are collaborating to create Rwanda's first School of Dentistry as part of the Human Resources for Health (HRH) Rwanda initiative that aims to strengthen the health care system of Rwanda. The HRH oral health team developed three management tools to measure progress in systems-strengthening efforts: 1) the road map is an operations plan for the entire dental school and facilitates delivery of the curriculum and management of human and material resources; 2) each HRH U.S. faculty member develops a work plan with targeted deliverables for his or her rotation, which is facilitated with biweekly flash reports that measure progress and keep the faculty member focused on his or her specific deliverables; and 3) the redesigned HRH twinning model, changed from twinning of an HRH faculty member with a single Rwandan faculty member to twinning with multiple Rwandan faculty members based on shared academic interests and goals, has improved efficiency, heightened engagement of the UR dental faculty, and increased the impact of HRH U.S. faculty members. These new tools enable the team to measure its progress toward the collaborative's goals and understand the successes and challenges in moving toward the planned targets. The tools have been valuable instruments in fostering discussion around priorities and deployment of resources as well as in developing strong relationships, enabling two-way exchange of knowledge, and promoting sustainability.

  9. Alcohol Inhibits Odontogenic Differentiation of Human Dental Pulp Cells by Activating mTOR Signaling.

    Science.gov (United States)

    Qin, Wei; Huang, Qi-Ting; Weir, Michael D; Song, Zhi; Fouad, Ashraf F; Lin, Zheng-Mei; Zhao, Liang; Xu, Hockin H K

    2017-01-01

    Long-term heavy alcohol consumption could result in a range of health, social, and behavioral problems. People who abuse alcohol are at high risks of seriously having osteopenia, periodontal disease, and compromised oral health. However, the role of ethanol (EtOH) in the biological functions of human dental pulp cells (DPCs) is unknown. Whether EtOH affects the odontoblastic differentiation of DPCs through the mechanistic target of rapamycin (mTOR) remains unexplored. The objective of this study was to investigate the effects of EtOH on DPC differentiation and mineralization. DPCs were isolated and purified from human dental pulps. The proliferation and odontoblastic differentiation of DPCs treated with EtOH were subsequently investigated. Different doses of EtOH were shown to be cytocompatible with DPCs. EtOH significantly activated the mTOR pathway in a dose-dependent manner. In addition, EtOH downregulated the alkaline phosphatase activity, attenuated the mineralized nodule formation, and suppressed the expression of odontoblastic markers including ALP, DSPP, DMP-1, Runx2, and OCN. Moreover, the pretreatment with rapamycin, a specific mTOR inhibitor, markedly reversed the EtOH-induced odontoblastic differentiation and cell mineralization. Our findings show for the first time that EtOH can suppress DPC differentiation and mineralization in a mTOR-dependent manner, indicating that EtOH may be involved in negatively regulating the dental pulp repair.

  10. Distribution of Human papilloma virus genotypes in cervical cancer tissues

    Directory of Open Access Journals (Sweden)

    Stamenković M.

    2014-01-01

    Full Text Available Cervical cancer incidence and mortality rates in Serbia are among the highest in Europe and data on Human papilloma virus (HPV type distribution are scarce. The aim of this study was to determine the prevalence of HPV types in archival specimens of cervical cancer tissues of women in the Serbian population. A total of 45 paraffin-embedded tissue samples of cervical carcinoma were used in this study. The procedure included deparaffinization of tissue samples, DNA extraction, PCR, gel electrophoresis and HPV genotyping by direct sequencing. HPV was detected in 32 samples (71%. Genotyping revealed the presence of 6 high-risk HPV types 16, 18, 33, 45, 53 and 58, where HPV type 16 was the most prevalent type (73.7%. The results of this study and further studies will provide more detailed information about HPV genotype distribution and may contribute to the formulation of national guidelines for the prevention of cervical cancer. [175073

  11. Crystal Structure Studies of Human Dental Apatite as a Function of Age

    Directory of Open Access Journals (Sweden)

    Th. Leventouri

    2009-01-01

    Full Text Available Studies of the average crystal structure properties of human dental apatite as a function of age in the range of 5–87 years are reported. The crystallinity of the dental hydroxyapatite decreases with the age. The a-lattice constant that is associated with the carbonate content in carbonate apatite decreases with age in a systematic way, whereas the c-lattice constant does not change significantly. Thermogravimetric measurements demonstrate an increase of the carbonate content with the age. FTIR spectroscopy reveals both B and A-type carbonate substitutions with the B-type greater than the A-type substitution by a factor up to ~5. An increase of the carbonate content as a function of age can be deduced from the ratio of the 2CO3 to the 1PO4 IR modes.

  12. Detection of human papillomavirus in dental biofilm and the uterine cervix of a pregnant adolescent.

    Science.gov (United States)

    Cavalcanti, Édila Figuerêdo Feitosa; Silva, Célia Regina; Ferreira, Dennis Carvalho; Ferreira, Mariana Vasconcellos Martins; Vanderborght, Patrícia Rosa; Torres, Maria Cynésia Medeiros Barros; Torres, Sandra Regina

    2016-01-01

    Adolescence and pregnancy are considered to be risk factors for human papillomavirus (HPV) infection. The relationship between this infection in the uterine cervix and oral HPV infection is controversial. This report describes a case of a pregnant 16-year-old adolescent who presented HPV infection in the uterine cervix and the mouth. Smears were collected from the cervix and the tongue/palate. Dental biofilm samples were also collected. The microarray technique was used to detect HPV. The HPV 56 subtype was observed in the cervical smear and HPV 6 in dental biofilm. In this pregnant adolescent, HPV infection was present in both the cervix and the mouth, but the HPV subtypes infecting these two areas were different.

  13. Adipose tissue macrophages impair preadipocyte differentiation in humans.

    Directory of Open Access Journals (Sweden)

    Li Fen Liu

    Full Text Available The physiologic mechanisms underlying the relationship between obesity and insulin resistance are not fully understood. Impaired adipocyte differentiation and localized inflammation characterize adipose tissue from obese, insulin-resistant humans. The directionality of this relationship is not known, however. The aim of the current study was to investigate whether adipose tissue inflammation is causally-related to impaired adipocyte differentiation.Abdominal subcutaneous(SAT and visceral(VAT adipose tissue was obtained from 20 human participants undergoing bariatric surgery. Preadipocytes were isolated, and cultured in the presence or absence of CD14+ macrophages obtained from the same adipose tissue sample. Adipocyte differentiation was quantified after 14 days via immunofluorescence, Oil-Red O, and adipogenic gene expression. Cytokine secretion by mature adipocytes cultured with or without CD14+macrophages was quantified.Adipocyte differentiation was significantly lower in VAT than SAT by all measures (p<0.001. With macrophage removal, SAT preadipocyte differentiation increased significantly as measured by immunofluorescence and gene expression, whereas VAT preadipocyte differentiation was unchanged. Adipocyte-secreted proinflammatory cytokines were higher and adiponectin lower in media from VAT vs SAT: macrophage removal reduced inflammatory cytokine and increased adiponectin secretion from both SAT and VAT adipocytes. Differentiation of preadipocytes from SAT but not VAT correlated inversely with systemic insulin resistance.The current results reveal that proinflammatory immune cells in human SAT are causally-related to impaired preadipocyte differentiation, which in turn is associated with systemic insulin resistance. In VAT, preadipocyte differentiation is poor even in the absence of tissue macrophages, pointing to inherent differences in fat storage potential between the two depots.

  14. Opalescence of human teeth and dental esthetic restorative materials.

    Science.gov (United States)

    Lee, Yong-Keun

    2016-12-01

    Human tooth enamel is opalescent, which renders teeth bluish in reflected and orange in transmitted color. The aim was to review opalescent property of teeth and application and mimetic reproduction in esthetic restorations. A PubMed search for articles published in English till 2015 on the opalescence of teeth and esthetic materials revealed 29 relevant papers. Opalescence was measured with OP-RT index, which was calculated as the difference in the yellow-blue and red-green color coordinates between the reflected and transmitted colors. Mean OP-RT value of human enamel was 22.9. OP-RT values of direct resin composites changed after polymerization, and the range in these materials was 5.7-23.7. OP-RT value ranges were 1.6-6.1 and 2.0-7.1 for the core and veneer ceramics, respectively. Since the OP-RT values of esthetic materials were lower than that of enamel, it is recommended that materials that can reproduce the opalescence of enamel be further designed.

  15. Bioprinted three dimensional human tissues for toxicology and disease modeling.

    Science.gov (United States)

    Nguyen, Deborah G; Pentoney, Stephen L

    2017-03-01

    The high rate of attrition among clinical-stage therapies, due largely to an inability to predict human toxicity and/or efficacy, underscores the need for in vitro models that better recapitulate in vivo human biology. In much the same way that additive manufacturing has revolutionized the production of solid objects, three-dimensional (3D) bioprinting is enabling the automated production of more architecturally and functionally accurate in vitro tissue culture models. Here, we provide an overview of the most commonly used bioprinting approaches and how they are being used to generate complex in vitro tissues for use in toxicology and disease modeling research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Sympathetic reflex control of blood flow in human peripheral tissues

    DEFF Research Database (Denmark)

    Henriksen, O

    1991-01-01

    Sympathetic vasoconstrictor reflexes are essential for the maintenance of arterial blood pressure in upright position. It has been generally believed that supraspinal sympathetic vasoconstrictor reflexes elicited by changes in baroreceptor activity play an important role. Recent studies on human...... sympathetic vasoconstrictor reflexes are blocked. Blood flow has been measure by the local 133Xe-technique. The results indicate the presence of spinal as well as supraspinal sympathetic vasoconstrictor reflexes to human peripheral tissues. Especially is emphasized the presence of a local sympathetic veno...... skeletal muscle, cutaneous and subcutaneous tissues of the limbs indicate that the situation is more complex. Measurements have been carried out during acute as well as chronic sympathetic denervation. Spinal sympathetic reflex mechanisms have been evaluated in tetraplegic patients, where supraspinal...

  17. Engineering bone tissue from human embryonic stem cells

    OpenAIRE

    Marolt, Darja; Campos, Iván Marcos; Bhumiratana, Sarindr; Koren, Ana; Petridis, Petros; Zhang, Geping; Spitalnik, Patrice F.; Grayson, Warren L.; Vunjak-Novakovic, Gordana

    2012-01-01

    In extensive bone defects, tissue damage and hypoxia lead to cell death, resulting in slow and incomplete healing. Human embryonic stem cells (hESC) can give rise to all specialized lineages found in healthy bone and are therefore uniquely suited to aid regeneration of damaged bone. We show that the cultivation of hESC-derived mesenchymal progenitors on 3D osteoconductive scaffolds in bioreactors with medium perfusion leads to the formation of large and compact bone constructs. Notably, the i...

  18. Streamlined bioreactor-based production of human cartilage tissues.

    Science.gov (United States)

    Tonnarelli, B; Santoro, R; Adelaide Asnaghi, M; Wendt, D

    2016-05-27

    Engineered tissue grafts have been manufactured using methods based predominantly on traditional labour-intensive manual benchtop techniques. These methods impart significant regulatory and economic challenges, hindering the successful translation of engineered tissue products to the clinic. Alternatively, bioreactor-based production systems have the potential to overcome such limitations. In this work, we present an innovative manufacturing approach to engineer cartilage tissue within a single bioreactor system, starting from freshly isolated human primary chondrocytes, through the generation of cartilaginous tissue grafts. The limited number of primary chondrocytes that can be isolated from a small clinically-sized cartilage biopsy could be seeded and extensively expanded directly within a 3D scaffold in our perfusion bioreactor (5.4 ± 0.9 doublings in 2 weeks), bypassing conventional 2D expansion in flasks. Chondrocytes expanded in 3D scaffolds better maintained a chondrogenic phenotype than chondrocytes expanded on plastic flasks (collagen type II mRNA, 18-fold; Sox-9, 11-fold). After this "3D expansion" phase, bioreactor culture conditions were changed to subsequently support chondrogenic differentiation for two weeks. Engineered tissues based on 3D-expanded chondrocytes were more cartilaginous than tissues generated from chondrocytes previously expanded in flasks. We then demonstrated that this streamlined bioreactor-based process could be adapted to effectively generate up-scaled cartilage grafts in a size with clinical relevance (50 mm diameter). Streamlined and robust tissue engineering processes, as the one described here, may be key for the future manufacturing of grafts for clinical applications, as they facilitate the establishment of compact and closed bioreactor-based production systems, with minimal automation requirements, lower operating costs, and increased compliance to regulatory guidelines.

  19. Composition of MRI phantom equivalent to human tissues

    International Nuclear Information System (INIS)

    Kato, Hirokazu; Kuroda, Masahiro; Yoshimura, Koichi; Yoshida, Atsushi; Hanamoto, Katsumi; Kawasaki, Shoji; Shibuya, Koichi; Kanazawa, Susumu

    2005-01-01

    We previously developed two new MRI phantoms (called the CAG phantom and the CAGN phantom), with T1 and T2 relaxation times equivalent to those of any human tissue at 1.5 T. The conductivity of the CAGN phantom is equivalent to that of most types of human tissue in the frequency range of 1 to 130 MHz. In this paper, the relaxation times of human tissues are summarized, and the composition of the corresponding phantoms are provided in table form. The ingredients of these phantoms are carrageenan as the gelling agent, GdCl 3 as a T1 modifier, agarose as a T2 modifier, NaCl (CAGN phantom only) as a conductivity modifier, NaN 3 as an antiseptic, and distilled water. The phantoms have T1 values of 202-1904 ms and T2 values of 38-423 ms when the concentrations of GdCl 3 and agarose are varied from 0-140 μmol/kg, and 0%-1.6%, respectively, and the CAGN phantom has a conductivity of 0.27-1.26 S/m when the NaCl concentration is varied from 0%-0.7%. These phantoms have sufficient strength to replicate a torso without the use of reinforcing agents, and can be cut by a knife into any shape. We anticipate the CAGN phantom to be highly useful and practical for MRI and hyperthermia-related research

  20. Ionizing radiation induces senescence and differentiation of human dental pulp stem cells.

    Science.gov (United States)

    Havelek, R; Soukup, T; Ćmielová, J; Seifrtová, M; Suchánek, J; Vávrová, J; Mokrý, J; Muthná, D; Řezáčová, M

    2013-01-01

    Head and neck cancer is one of the most common cancers in Europe. Many current anti-cancer treatments, including ionizing radiation, induce apoptosis via DNA damage. Unfortunately, such treatments are non-selective to cancer cells and produce similar toxicity in normal cells, including adult stem cells. One of the fundamental properties of an adult stem cell is that it does not have any tissue-specific structures that allow it to perform specialized functions. However, under certain stimuli, unspecialized adult stem cells can give rise to specialized cells to generate replacements for cells that are lost during one's life or due to injury or disease. Nevertheless, specialization of stem cells must be controlled by specific milieu and also initiated at the proper time, making the entire process beneficial for tissue recovery and maintaining it for a long time. In this paper we assess whether irradiated dental pulp stem cells have maintained open their options to mature into specialized cells, or whether they have lost their unspecialized (immature) state following irradiation. Our findings showed radiation-induced premature differentiation of dental pulp stem cells towards odonto-/osteoblast lineages in vitro. Matrix calcification was visualized from Day 6 or Day 9 following irradiation of cells expressing low or high levels of CD146, respectively.

  1. Expression cartography of human tissues using self organizing maps

    Directory of Open Access Journals (Sweden)

    Löffler Markus

    2011-07-01

    Full Text Available Abstract Background Parallel high-throughput microarray and sequencing experiments produce vast quantities of multidimensional data which must be arranged and analyzed in a concerted way. One approach to addressing this challenge is the machine learning technique known as self organizing maps (SOMs. SOMs enable a parallel sample- and gene-centered view of genomic data combined with strong visualization and second-level analysis capabilities. The paper aims at bridging the gap between the potency of SOM-machine learning to reduce dimension of high-dimensional data on one hand and practical applications with special emphasis on gene expression analysis on the other hand. Results The method was applied to generate a SOM characterizing the whole genome expression profiles of 67 healthy human tissues selected from ten tissue categories (adipose, endocrine, homeostasis, digestion, exocrine, epithelium, sexual reproduction, muscle, immune system and nervous tissues. SOM mapping reduces the dimension of expression data from ten of thousands of genes to a few thousand metagenes, each representing a minicluster of co-regulated single genes. Tissue-specific and common properties shared between groups of tissues emerge as a handful of localized spots in the tissue maps collecting groups of co-regulated and co-expressed metagenes. The functional context of the spots was discovered using overrepresentation analysis with respect to pre-defined gene sets of known functional impact. We found that tissue related spots typically contain enriched populations of genes related to specific molecular processes in the respective tissue. Analysis techniques normally used at the gene-level such as two-way hierarchical clustering are better represented and provide better signal-to-noise ratios if applied to the metagenes. Metagene-based clustering analyses aggregate the tissues broadly into three clusters containing nervous, immune system and the remaining tissues

  2. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells

    Science.gov (United States)

    Sonoda, Soichiro; Yamaza, Haruyoshi; Ma, Lan; Tanaka, Yosuke; Tomoda, Erika; Aijima, Reona; Nonaka, Kazuaki; Kukita, Toshio; Shi, Songtao; Nishimura, Fusanori; Yamaza, Takayoshi

    2016-01-01

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we examined the stem cell potency of IP-DPSCs. In comparison with healthy DPSCs, IP-DPSCs expressed lower colony-forming capacity, population-doubling rate, cell proliferation, multipotency, in vivo dentin regeneration, and immunosuppressive activity, suggesting that intact IP-DPSCs may be inadequate for dentin/pulp regeneration. Therefore, we attempted to improve the impaired in vivo dentin regeneration and in vitro immunosuppressive functions of IP-DPSCs to enable dentin/pulp regeneration. Interferon gamma (IFN-γ) treatment enhanced in vivo dentin regeneration and in vitro T cell suppression of IP-DPSCs, whereas treatment with tumor necrosis factor alpha did not. Therefore, these findings suggest that IFN-γ may be a feasible modulator to improve the functions of impaired IP-DPSCs, suggesting that autologous transplantation of IFN-γ-accelerated IP-DPSCs might be a promising new therapeutic strategy for dentin/pulp tissue engineering in future endodontic treatment. PMID:26775677

  3. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells.

    Science.gov (United States)

    Sonoda, Soichiro; Yamaza, Haruyoshi; Ma, Lan; Tanaka, Yosuke; Tomoda, Erika; Aijima, Reona; Nonaka, Kazuaki; Kukita, Toshio; Shi, Songtao; Nishimura, Fusanori; Yamaza, Takayoshi

    2016-01-18

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we examined the stem cell potency of IP-DPSCs. In comparison with healthy DPSCs, IP-DPSCs expressed lower colony-forming capacity, population-doubling rate, cell proliferation, multipotency, in vivo dentin regeneration, and immunosuppressive activity, suggesting that intact IP-DPSCs may be inadequate for dentin/pulp regeneration. Therefore, we attempted to improve the impaired in vivo dentin regeneration and in vitro immunosuppressive functions of IP-DPSCs to enable dentin/pulp regeneration. Interferon gamma (IFN-γ) treatment enhanced in vivo dentin regeneration and in vitro T cell suppression of IP-DPSCs, whereas treatment with tumor necrosis factor alpha did not. Therefore, these findings suggest that IFN-γ may be a feasible modulator to improve the functions of impaired IP-DPSCs, suggesting that autologous transplantation of IFN-γ-accelerated IP-DPSCs might be a promising new therapeutic strategy for dentin/pulp tissue engineering in future endodontic treatment.

  4. Human dental stem cells suppress PMN activity after infection with the periodontopathogens Prevotella intermedia and Tannerella forsythia

    Science.gov (United States)

    Hieke, Cathleen; Kriebel, Katja; Engelmann, Robby; Müller-Hilke, Brigitte; Lang, Hermann; Kreikemeyer, Bernd

    2016-01-01

    Periodontitis is characterized by inflammation associated with the colonization of different oral pathogens. We here aimed to investigate how bacteria and host cells shape their environment in order to limit inflammation and tissue damage in the presence of the pathogen. Human dental follicle stem cells (hDFSCs) were co-cultured with gram-negative P. intermedia and T. forsythia and were quantified for adherence and internalization as well as migration and interleukin secretion. To delineate hDFSC-specific effects, gingival epithelial cells (Ca9-22) were used as controls. Direct effects of hDFSCs on neutrophils (PMN) after interaction with bacteria were analyzed via chemotactic attraction, phagocytic activity and NET formation. We show that P. intermedia and T. forsythia adhere to and internalize into hDFSCs. This infection decreased the migratory capacity of the hDFSCs by 50%, did not disturb hDFSC differentiation potential and provoked an increase in IL-6 and IL-8 secretion while leaving IL-10 levels unaltered. These environmental modulations correlated with reduced PMN chemotaxis, phagocytic activity and NET formation. Our results suggest that P. intermedia and T. forsythia infected hDFSCs maintain their stem cell functionality, reduce PMN-induced tissue and bone degradation via suppression of PMN-activity, and at the same time allow for the survival of the oral pathogens. PMID:27974831

  5. Skeletal, dental and soft tissue changes in Class III patients treated with fixed appliances and lower premolar extractions.

    Science.gov (United States)

    Abu Alhaija, Elham S J; Al-Khateeb, Susan N

    2011-05-01

    Mild Class III malocciusions can be treated by upper incisor proclination and lower incisor retroclination following extraction of the lower first premolars. To compare the skeletal, dental and soft tissue changes in Class III patients treated with fixed appliances, Class III traction and lower first premolar extractions with the changes in a group of untreated Class III patients. The Treatment group consisted of 30 Class III patients (Mean age 13.69 +/- 1.48 years) who were treated by upper and lower fixed appliances, Class III intermaxillary traction and lower first premolar extractions for 2.88 +/- 1.12 years. The Control group consisted of 20 untreated Class III patients (Mean age 13.51 +/- 0.95) matched for age and gender. The T1 to T2 changes in the treated and untreated groups were compared using a paired t-test while differences between the two groups were compared with an independent t-test. During treatment, the upper incisors were proclined about 1 degree and the lower incisors were retroclined 8 degrees. Small, but statistically significant changes in SNB, Wits and the overlying soft tissues accompanied the changes in incisor inclination. At the end of treatment a positive overbite and overjet were achieved. The increase in lower facial height in the Treatment group was comparable with the change in the Control group. A range of mild to moderate Class III malocclusions can be treated by dentoalveolar compensation.

  6. Hard tissue deposition in dental pulp canal by {alpha}-tricalcium phosphate cement

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, M.; Toda, T. [Osaka Dental Univ. (Japan). Dept. of Endodontics; Mandai, Y. [Bio-Chemical Lab. of Nitta Gelatin Inc., Yao (Japan); Oonishi, H. [Osaka Minami National Hospital, Kawachi (Japan). Dept. of Orthopaedic Surgery

    2001-07-01

    Canal closure by hard tissue proliferation in the pulp canal and/or apical foramen is the most ideal healing after pulp removal. Generally, Ca(OH){sub 2} may induce secondary dentine or dentine-bridge on the amputated pulp surface. However, Ca(OH){sub 2} shows strong alkalinity and may cause severe inflammatory responses in the residual pulp. Moreover, completely formed dentine-bridge at the orifice will disturb further treatment of residual pulp because of the difficulty in localizing the pathway. The purpose of this study was to see hard tissue induction using newly developed {alpha}-tricalcium phosphate cement and to recognize the morphological difference of hard tissue from that of Ca(OH){sub 2}. (orig.)

  7. A color contrast aided density imaging technique to differentiate between dental hard tissues and its relevance

    Directory of Open Access Journals (Sweden)

    Devi Charan Shetty

    2011-01-01

    Full Text Available Aim: Radiographic interpretation of a disease requires knowledge about normal structures. The calcifying jaw diseases can range from radiolucent areas to varying degrees of calcification. Therefore, it is vital to differentiate radiographically between various hard tissues. Materials and Methods: We have illustrated the use of computed tomography scan to quantify the calcified structures as dentin and enamel in a case of ameloblastic fibro-odontoma. Results: The enamel, dentin and cementum showed different values. Conclusion: The "Dentascan" can be used to distinguish the hard tissues in a variety of calcifying diseases of jaws.

  8. A New Method to Develop Human Dental Pulp Cells and Platelet-rich Fibrin Complex.

    Science.gov (United States)

    He, Xuan; Chen, Wen-Xia; Ban, Guifei; Wei, Wei; Zhou, Jun; Chen, Wen-Jin; Li, Xian-Yu

    2016-11-01

    Platelet-rich fibrin (PRF) has been used as a scaffold material in various tissue regeneration studies. In the previous methods to combine seed cells with PRF, the structure of PRF was damaged, and the manipulation time in vitro was also increased. The objective of this in vitro study was to explore an appropriate method to develop a PRF-human dental pulp cell (hDPC) complex to maintain PRF structure integrity and to find out the most efficient part of PRF. The PRF-hDPC complex was developed at 3 different time points during PRF preparation: (1) the before centrifugation (BC) group, the hDPC suspension was added to the venous blood before blood centrifugation; (2) the immediately after centrifugation (IAC) group, the hDPC suspension was added immediately after blood centrifugation; (3) the after centrifugation (AC) group, the hDPC suspension was added 10 minutes after blood centrifugation; and (4) the control group, PRF without hDPC suspension. The prepared PRF-hDPC complexes were cultured for 7 days. The samples were fixed for histologic, immunohistochemistry, and scanning electron microscopic evaluation. Real-time polymerase chain reaction was performed to evaluate messenger RNA expression of alkaline phosphatase and dentin sialophosphoprotein. Enzyme-linked immunosorbent assay quantification for growth factors was performed within the different parts of the PRF. Histologic, immunohistochemistry, and scanning electron microscopic results revealed that hDPCs were only found in the BC group and exhibited favorable proliferation. Real-time polymerase chain reaction revealed that alkaline phosphatase and dentin sialophosphoprotein expression increased in the cultured PRF-hDPC complex. The lower part of the PRF released the maximum quantity of growth factors. Our new method to develop a PRF-hDPCs complex maintained PRF structure integrity. The hDPCs were distributed in the buffy coat, which might be the most efficient part of PRF. Copyright © 2016 American

  9. Human immature dental pulp stem cells (hIDPSCs), their application to cell therapy and bioengineering: an analysis by systematic revision of the last decade of literature.

    Science.gov (United States)

    de Souza, Priscilla Vianna; Alves, Fabiana Bucholdz Teixeira; Costa Ayub, Cristina Lucia Sant'Ana; de Miranda Soares, Maria Albertina; Gomes, Jose Rosa

    2013-12-01

    During recent years, attention has been given to the potential of therapeutic approaches using stem cells obtained from dental pulp tissue. The aim of this study, therefore, was to give an overview of the papers produced during the last 10 years that have described the use of stem cells obtained from human deciduous teeth in cell therapy or bioengineering. The PubMed database was investigated from January 2002 until July 2011 and the papers published during this period were analyzed according to criteria previously established, using the methodology of systematic review. The measurements were done using "stem cell" as the primary keyword, and "human deciduous teeth dental pulp cell" and "human exfoliated deciduous teeth" as the secondary keywords. Four hundred and seventy-five papers were found. The first screening resulted in 276 papers, from which 84 papers were selected. However, only 11 of them attained the aim proposed in our approach. There were few scientific studies related to direct therapeutic application using stem cells of human deciduous teeth and none of them had been applied to humans. However, the results indicated important and promising applications of the pulp stem-cells in cell therapy and bioengineering as demonstrated by studies in animal models of muscular dystrophy, Parkison's disease, and lupus erythematosus. Copyright © 2013 Wiley Periodicals, Inc.

  10. PVA matches human liver in needle-tissue interaction.

    Science.gov (United States)

    de Jong, Tonke L; Pluymen, Loes H; van Gerwen, Dennis J; Kleinrensink, Gert-Jan; Dankelman, Jenny; van den Dobbelsteen, John J

    2017-05-01

    Medical phantoms can be used to study needle-tissue interaction and to train medical residents. The purpose of this research is to study the suitability of polyvinyl alcohol (PVA) as a liver tissue mimicking material in terms of needle-tissue interaction. Insertions into ex-vivo human livers were used for reference. Six PVA samples were created by varying the mass percentage of PVA to water (4m% and 7m%) and the number of freeze-thaw cycles (1, 2 and 3 cycles, 16hours of freezing at -19°C, 8hours of thawing). The inner needle of an 18 Gauge trocar needle with triangular tip was inserted 13 times into each of the samples, using an insertion velocity of 5 mm/s. In addition, 39 insertions were performed in two ex-vivo human livers. Axial forces on the needle were captured during insertion and retraction and characterized by friction along the needle shaft, peak forces, and number of peak forces per unit length. The concentration of PVA and the number of freeze-thaw cycles both influenced the mechanical interaction between needle and specimen. Insertions into 4m% PVA phantoms with 2 freeze-thaw cycles were comparable to human liver in terms of estimated friction along the needle shaft and the number of peak forces. Therefore, these phantoms are considered to be suitable liver mimicking materials for image-guided needle interventions. The mechanical properties of PVA hydrogels can be influenced in a controlled manner by varying the concentration of PVA and the number of freeze-thaw cycles, to mimic liver tissue characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Formation of Hyaline Cartilage Tissue by Passaged Human Osteoarthritic Chondrocytes.

    Science.gov (United States)

    Bianchi, Vanessa J; Weber, Joanna F; Waldman, Stephen D; Backstein, David; Kandel, Rita A

    2017-02-01

    When serially passaged in standard monolayer culture to expand cell number, articular chondrocytes lose their phenotype. This results in the formation of fibrocartilage when they are used clinically, thus limiting their use for cartilage repair therapies. Identifying a way to redifferentiate these cells in vitro is critical if they are to be used successfully. Transforming growth factor beta (TGFβ) family members are known to be crucial for regulating differentiation of fetal limb mesenchymal cells and mesenchymal stromal cells to chondrocytes. As passaged chondrocytes acquire a progenitor-like phenotype, the hypothesis of this study was that TGFβ supplementation will stimulate chondrocyte redifferentiation in vitro in serum-free three-dimensional (3D) culture. Human articular chondrocytes were serially passaged twice (P2) in monolayer culture. P2 cells were then placed in high-density (3D) culture on top of membranes (Millipore) and cultured for up to 6 weeks in chemically defined serum-free redifferentiation media (SFRM) in the presence or absence of TGFβ. The tissues were evaluated histologically, biochemically, by immunohistochemical staining, and biomechanically. Passaged human chondrocytes cultured in SFRM supplemented with 10 ng/mL TGFβ3 consistently formed a continuous layer of articular-like cartilage tissue rich in collagen type 2 and aggrecan and lacking collagen type 1 and X in the absence of a scaffold. The tissue developed a superficial zone characterized by expression of lubricin and clusterin with horizontally aligned collagen fibers. This study suggests that passaged human chondrocytes can be used to bioengineer a continuous layer of articular cartilage-like tissue in vitro scaffold free. Further study is required to evaluate their ability to repair cartilage defects in vivo.

  12. Phase transformations in a human tooth tissue at the initial stage of caries.

    Directory of Open Access Journals (Sweden)

    Pavel Seredin

    Full Text Available The aim of the paper is to study phase transformations in solid tissues of the human teeth during the development of fissure caries by Raman and fluorescence microspectroscopy. The study of the areas with fissure caries confirmed the assumption of the formation of a weak interaction between phosphate apatite enamel and organic acids (products of microorganisms. The experimental results obtained with by Raman microspectroscopy showed the formation of dicalcium phosphate dihydrate - CaHPO4-2H2O in the area of mural demineralization of carious fissure. A comparative analysis of structural and spectroscopic data for the intact and carious enamel shows that emergence of a more soluble phase - carbonate-substituted hydroxyapatite - is typical for the initial stage of caries. It is shown that microareas of dental hard tissues in the carious fissure due to an emerging misorientation of apatite crystals have a higher fluorescence yield than the area of the intact enamel. These areas can be easily detected even prior to a deep demineralization (white spot stage for the case of irreversibly changed organomineral complex and intensive removal of the mineral component.

  13. Phase Transformations in a Human Tooth Tissue at the Initial Stage of Caries

    Science.gov (United States)

    Prutskij, Tatiana; Ippolitov, Yury

    2015-01-01

    The aim of the paper is to study phase transformations in solid tissues of the human teeth during the development of fissure caries by Raman and fluorescence microspectroscopy. The study of the areas with fissure caries confirmed the assumption of the formation of a weak interaction between phosphate apatite enamel and organic acids (products of microorganisms). The experimental results obtained with by Raman microspectroscopy showed the formation of dicalcium phosphate dihydrate - CaHPO4-2H2O in the area of mural demineralization of carious fissure. A comparative analysis of structural and spectroscopic data for the intact and carious enamel shows that emergence of a more soluble phase - carbonate-substituted hydroxyapatite - is typical for the initial stage of caries. It is shown that microareas of dental hard tissues in the carious fissure due to an emerging misorientation of apatite crystals have a higher fluorescence yield than the area of the intact enamel. These areas can be easily detected even prior to a deep demineralization (white spot stage) for the case of irreversibly changed organomineral complex and intensive removal of the mineral component. PMID:25901743

  14. Non-Metric Dental Traits in Human Skeletal Remains from Transcaucasian Populations: Phylogenetic and Diachronic Evidence

    Directory of Open Access Journals (Sweden)

    Khudaverdyan Anahit Yu.

    2014-07-01

    Full Text Available The aim of the study is the assessment of biological distance between populations from Transcaucasia on the basis of the frequency of dental morphological traits. It is well known that these traits are characterised by a high inter-population differentiation, low sexual dimorphism, and their recording is loaded by relatively small intra and inter observer error. The dental morphological traits are successfully used in the description and explanation of the microevolutionary and ethnogenetic processes. This paper presents the results of the odontological differentiation of human populations from Transcaucasia. The comparative analysis was carried out on the basis of 12 groups. From the obtained results, we can draw the following conclusions: The populations of Armenian Highland and Georgia can be differentiated as far as the frequency of dental morphological traits are concerned. They also do not exhibit similar intragroup variability. Biocultural diversity of ancient Transcaucasian populations has not been studied extensively; therefore, delineating some of the patterns of phenotypic variation may be useful for understanding their ongoing evolution.

  15. The Effects of Triethylene Glycol Dimethacrylate (TEGDMA on the Protein of Human Dental Pulp Cells

    Directory of Open Access Journals (Sweden)

    Ratna Farida

    2013-07-01

    Full Text Available Triethylene glycol dimethacrylate (TEGDMA is a common component of the bonding agents and resin composites used in dentistry for restorative dentistry. However, TEGDMA could be released from composite resins following incomplete polymerization and degradation processes by salivary enzyme in the mouth. Subsequently, TEGDMA is available in saliva and diffuses toward and affects the dental pulp which contains various cells, and thus may cause severe cytotoxic effects. Objectives: To determine the total protein concentration of human dental ulp cells following exposure to TEGDMA. Materials and Methods: Dental pulp cells were isolated from the pulp of the freshly extracted teeth and cultured in DMEM for 48 h (37ºC, 5% CO2. Then, 2 mM and 4 mM, and 8 mM TEGDMA were added to these cells and incubated for 24 h. The total protein was measured by Bradford Protein Assay. Results: The total protein concentration of dental pulp cells after exposure to 4 mM, 8mM, and 12 mM TEGDMA were statistically lower (22762.27 µg/ml ± 3385.87; 20268.44 µg/ml ± 1701.14; 23706.51 µg/ml ± 3214.52; respectively than the control group (24253.77 µg/ml ± 3072.99. Furthermore, the total protein concentration of culture medium after exposure to 4 mM, 8 mM, and 2 mM TEGDMA, were statistically higher (28635.85 µg/ml ± 2373.4; 35288.41 µg/ml ± 3469.48; 38199.79 µg/ml ± 2752.47; respectively when compared with the controls (27073.83 µg/ml ± 2772.47. Conclusion: 2 mM, 4 mM, and 8 mM TEGDMA caused cytotoxity to human dental pulp cells chowed by decreasing the total protein of cells and increasing the total protein of the culture medium.DOI: 10.14693/jdi.v16i3.102

  16. The comparative distribution of thorium and plutonium in human tissues

    International Nuclear Information System (INIS)

    Singh, Narayani P.; Shawki Amin Ibrahim; Cohen, Norman; Wrenn, McDonald E.

    1978-01-01

    Thorium is the most chemically and biologically similar natural element to the manmade element plutonium. Both are actinides, and for both the most stable valency state is +4, and solubility in natural body fluids is low. They are classified together in ICRP Lung Model. The present paper deals with the question of whether or not the analogy between the two actinides in terms of deposition and retention in human tissues is a good one. Preliminary results on the thorium contents ( 228,230 Th and 232 Th) of three sets of human tissues from a western U.S. town containing a uranium tailings pile are compared with the reported values of plutonium content of human tissues from the general populations who are exposed to environmental plutonium from fallout of nuclear detonations. Samples were taken at autopsy where sudden death had occurred. For the three isotopes of thorium, the ratio of the content of each (pCi/organ, normalized by organ weight to ICRP Reference Man) in lung to lymph nodes varies from 2-25 for individuals with a mean of 8; this is similar to that we infer from the literature for 239 , 240 Pu which suggests a ratio of lung to lymph nodes with a mean of approximately 7. However, the relative thorium contents of lung and liver are dissimilar, lung/liver for thorium being 3.5 and for plutonium 0.2 to 0.1. Similarly, the ratios of thorium and plutonium content of liver and bone vary significantly; the ratio for thorium is 0.1 and for plutonium 0.8 to 0.5. The most significant observation at this stage is that the relative accumulation of thorium in human liver is much less than that of plutonium. Some of the plausible reasons will be discussed. (author)

  17. Implications of human tissue studies for radiation protection

    International Nuclear Information System (INIS)

    Kathren, R.L.

    1988-01-01

    Through radiochemical analysis of voluntary tissue donations, the U.S. Transuranium and Uranium Registries (USTR) are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole-body contributions to the USTR revealed an inverse proportionality between actinide concentration and bone ash. The analysis of a whole body with significant 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies with tissues obtained at autopsy suggest that existing biokinetic models for 238 Pu and 241 Am and the currently accepted models and limits on intake, which use these models as their basis, may be inaccurately implying that revisions of existing safety standards may be necessary. Other studies of the registries are designed to evaluate in-vivo estimates of actinide deposition with those derived from postmortem tissue analysis, to compare results of animal experiments with human data, and to review histopathologic slides for tissue changes that might be attributable to exposure to transuranic elements. The implications of these recent findings and other work of the registries is discussed from the standpoint of this potential effect on biokinetic modeling, internal dose assessment, and safety standards and operational health physics practices

  18. Implications of human tissue studies for radiation protection.

    Science.gov (United States)

    Kathren, R L

    1988-08-01

    Through radiochemical analysis of voluntary tissue donations, the U.S. Transuranium and Uranium Registries (USTR) are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole-body contributions to the USTR revealed an inverse proportionality between actinide concentration and bone ash. The analysis of a whole body with significant 241Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies with tissues obtained at autopsy suggest that existing biokinetic models for 238Pu and 241Am and the currently accepted models and limits on intake, which use these models as their basis, may be inaccurately implying that revisions of existing safety standards may be necessary. Other studies of the registries are designed to evaluate in-vivo estimates of actinide deposition with those derived from postmortem tissue analysis, to compare results of animal experiments with human data, and to review histopathologic slides for tissue changes that might be attributable to exposure to transuranic elements. The implications of these recent findings and other work of the registries is discussed from the standpoint of this potential effect on biokinetic modeling, internal dose assessment, and safety standards and operational health physics practices.

  19. Concentration of Po-210 and Pb-210 in human tissues

    International Nuclear Information System (INIS)

    Zhao Lancai; Takizawa, Y.; Yamamoto, M.

    1990-01-01

    The levels of Pb-210 and Po-210 in human tissues of people in Japan were determined. Various tissue samples were obtained at autopsy from the cadavers of 22 oncologic cases, mainly in Niigata Prefecture in northern Japan during the period of 1986 to 1988. Wet ashing, followed by electrochemical deposition and alpha-ray spectrometry were used to separate and determine the Pb-210 and Po-210 presented. Among the tissues analyzed the highest concentrations of Pb-210 and Po-210 were observed in bone, liver and kidneys: 1.29, 1.69 and 1.22 Bq.kg -1 respectively for Po-210, and 1.27, 0.56 and 0.43 Bq/kg for Pb-210 respectively. The Po-210/Pb-210 ratios in liver and kidney are 3.0 and 2.9 respectively. Po-210/Pb-210 ratios in other tissues are close to one. The total body burden of Pb-210 and Po-210 was found to be approximately 15.8 Bq and 19.1 Bq respectively

  20. Parallel beam microradiography of dental hard tissue using synchrotron radiation and X-ray image magnification

    International Nuclear Information System (INIS)

    Takagi, S.; Chow, L.C.; Brown, W.E.; Dobbyn, R.C.; Kuriyama, M.

    1984-01-01

    A novel technique utilizing a highly parallel beam of monochromatic synchrotron radiation combined with X-ray image magnification has been used to obtain microradiographs of caries lesions in relatively thick tooth sections. Preliminary results reveal structural features not previously reported. This technique holds the promise of allowing one to follow the structural changes accompanying the formation, destruction and chemical repair of mineralized tissue in real time. (orig.)

  1. Computational model of soft tissues in the human upper airway.

    Science.gov (United States)

    Pelteret, J-P V; Reddy, B D

    2012-01-01

    This paper presents a three-dimensional finite element model of the tongue and surrounding soft tissues with potential application to the study of sleep apnoea and of linguistics and speech therapy. The anatomical data was obtained from the Visible Human Project, and the underlying histological data was also extracted and incorporated into the model. Hyperelastic constitutive models were used to describe the material behaviour, and material incompressibility was accounted for. An active Hill three-element muscle model was used to represent the muscular tissue of the tongue. The neural stimulus for each muscle group was determined through the use of a genetic algorithm-based neural control model. The fundamental behaviour of the tongue under gravitational and breathing-induced loading is investigated. It is demonstrated that, when a time-dependent loading is applied to the tongue, the neural model is able to control the position of the tongue and produce a physiologically realistic response for the genioglossus.

  2. Cells in human postmortem brain tissue slices remain alive for several weeks in culture

    NARCIS (Netherlands)

    Verwer, Ronald W. H.; Hermens, Wim T. J. M. C.; Dijkhuizen, PaulaA; ter Brake, Olivier; Baker, Robert E.; Salehi, Ahmad; Sluiter, Arja A.; Kok, Marloes J. M.; Muller, Linda J.; Verhaagen, Joost; Swaab, Dick F.

    2002-01-01

    Animal models for human neurological and psychiatric diseases only partially mimic the underlying pathogenic processes. Therefore, we investigated the potential use of cultured postmortem brain tissue from adult neurological patients and controls. The present study shows that human brain tissue

  3. Immunophenotyping reveals the diversity of human dental pulp mesenchymal stromal cells in vivo and their evolution upon in vitro amplification

    Directory of Open Access Journals (Sweden)

    Maxime DUCRET

    2016-11-01

    Full Text Available Mesenchymal stromal/stem cells (MSCs from human dental pulp (DP can be expanded in vitro for cell-based and regenerative dentistry therapeutic purposes. However, their heterogeneity may be a hurdle to the achievement of reproducible and predictable therapeutic outcomes. To get a better knowledge about this heterogeneity, we designed a flow cytometric strategy to analyze the phenotype of DP cells in vivo and upon in vitro expansion with stem cell markers. We focused on the CD31- cell population to exclude endothelial and leukocytic cells. Results showed that the in vivo CD31- DP cell population contained 1.4% of CD56+, 1.5% of CD146+, 2.4% of CD271+ and 6.3% of MSCA-1+ cells but very few Stro-1+ cells (≤1%. CD56+, CD146+, CD271+ and MSCA-1+ cell subpopulations expressed various levels of these markers. CD146+MSCA-1+, CD271+MSCA-1+ and CD146+CD271+ cells were the most abundant DP-MSC populations. Analysis of DP-MSCs expanded in vitro with a medicinal manufacturing approach showed that CD146 was expressed by about 50% of CD56+, CD271+, MSCA-1+ and Stro-1+ cells, and MSCA-1 by 15-30% of CD56+, CD146+, CD271+ and Stro-1+ cells. These ratios remained stable with passages. CD271 and Stro-1 were expressed by less than 1% of the expanded cell populations. Interestingly, the percentage of CD56+ cells strongly increased from P1 (25% to P4 (80% both in all sub-populations studied. CD146+CD56+, MSCA-1+CD56+ and CD146+MSCA-1+ cells were the most abundant DP-MSCs at the end of P4. These results established that DP-MSCs constitute a heterogeneous mixture of cells in pulp tissue in vivo and in culture, and that their phenotype is modified upon in vitro expansion. Further studies are needed to determine whether co-expression of specific MSC markers confers DP cells specific properties that could be used for the regeneration of human tissues, including the dental pulp, with standardized cell-based medicinal products.

  4. Immunohistochemical Expression of TGF-β1 and Osteonectin in engineered and Ca(OH2-repaired human pulp tissues

    Directory of Open Access Journals (Sweden)

    Luiz Alexandre CHISINI

    Full Text Available Abstract The aim of the present study was to evaluate the expression of transforming growth factor-β1 (TGF-β1 and osteonectin (ON in pulp-like tissues developed by tissue engineering and to compare it with the expression of these proteins in pulps treated with Ca(OH2 therapy. Tooth slices were obtained from non-carious human third molars under sterile procedures. The residual periodontal and pulp soft tissues were removed. Empty pulp spaces of the tooth slice were filled with sodium chloride particles (250–425 µm. PLLA solubilized in 5% chloroform was applied over the salt particles. The tooth slice/scaffold (TS/S set was stored overnight and then rinsed thoroughly to wash out the salt. Scaffolds were previously sterilized with ethanol (100–70° and washed with phosphate-buffered saline (PBS. TS/S was treated with 10% EDTA and seeded with dental pulp stem cells (DPSC. Then, TS/S was implanted into the dorsum of immunodeficient mice for 28 days. Human third molars previously treated with Ca(OH2 for 90 days were also evaluated. Samples were prepared and submitted to histological and immunohistochemical (with anti-TGF-β1, 1:100 and anti-ON, 1:350 analyses. After 28 days, TS/S showed morphological characteristics similar to those observed in dental pulp treated with Ca(OH2. Ca(OH2-treated pulps showed the usual repaired pulp characteristics. In TS/S, newly formed tissues and pre-dentin was colored, which elucidated the expression of TGF-β1 and ON. Immunohistochemistry staining of Ca(OH2-treated pulps showed the same expression patterns. The extracellular matrix displayed a fibrillar pattern under both conditions. Regenerative events in the pulp seem to follow a similar pattern of TGF-β1 and ON expression as the repair processes.

  5. Mining the human tissue proteome for protein citrullination.

    Science.gov (United States)

    Lee, Chien-Yun; Wang, Dongxue; Wilhelm, Mathias; Zolg, Daniel Paul; Schmidt, Tobias; Schnatbaum, Karsten; Reimer, Ulf; Pontén, Fredrik; Uhlén, Mathias; Hahne, Hannes; Kuster, Bernhard

    2018-04-02

    Citrullination is a post-translational modification of arginine catalyzed by five peptidylarginine deiminases (PADs) in humans. The loss of a positive charge may cause structural or functional alterations and while the modification has been linked to several diseases including rheumatoid arthritis and cancer, its physiological or pathophysiological roles remain largely unclear. In part this is owing to limitations in available methodology able to robustly enrich, detect and localize the modification. As a result, only few citrullination sites have been identified on human proteins with high confidence. In this study, we mined data from mass spectrometry-based deep proteomic profiling of 30 human tissues to identify citrullination sites on endogenous proteins. Database searching of ~70 million tandem mass spectra yielded ~13,000 candidate spectra which were further triaged by spectrum quality metrics and the detection of the specific neutral loss of isocyanic acid from citrullinated peptides to reduce false positives. Because citrullination is easily confused with deamidation, we synthetized ~2,200 citrullinated and 1,300 deamidated peptides to build a library of reference spectra. This led to the validation of 375 citrullination sites on 209 human proteins. Further analysis showed that >80% of the identified modifications sites were new and for 56% of the proteins, citrullination was detected for the first time. Sequence motif analysis revealed a strong preference for Asp and Gly, residues around the citrullination site. Interestingly, while the modification was detected in 26 human tissues with the highest levels found in brain and lung, citrullination levels did not correlate well with protein expression of the PAD enzymes. Even though the current work represents the largest survey of protein citrullination to date, the modification was mostly detected on high abundant proteins arguing that the development of specific enrichment methods would be required in order

  6. Human mandible bone defect repair by the grafting of dental pulp stem/progenitor cells and collagen sponge biocomplexes

    Directory of Open Access Journals (Sweden)

    R d’Aquino

    2009-11-01

    Full Text Available In this study we used a biocomplex constructed from dental pulp stem/progenitor cells (DPCs and a collagen sponge scaffold for oro-maxillo-facial (OMF bone tissue repair in patients requiring extraction of their third molars. The experiments were carried out according to our Internal Ethical Committee Guidelines and written informed consent was obtained from the patients. The patients presented with bilateral bone reabsorption of the alveolar ridge distal to the second molar secondary to impaction of the third molar on the cortical alveolar lamina, producing a defect without walls, of at least 1.5 cm in height. This clinical condition does not permit spontaneous bone repair after extraction of the third molar, and eventually leads to loss also of the adjacent second molar. Maxillary third molars were extracted first for DPC isolation and expansion. The cells were then seeded onto a collagen sponge scaffold and the obtained biocomplex was used to fill in the injury site left by extraction of the mandibular third molars. Three months after autologous DPC grafting, alveolar bone of patients had optimal vertical repair and complete restoration of periodontal tissue back to the second molars, as assessed by clinical probing and X-rays. Histological observations clearly demonstrated the complete regeneration of bone at the injury site. Optimal bone regeneration was evident one year after grafting. This clinical study demonstrates that a DPC/collagen sponge biocomplex can completely restore human mandible bone defects and indicates that this cell population could be used for the repair and/or regeneration of tissues and organs.

  7. Experimental Human Cell and Tissue Models of Pemphigus

    Science.gov (United States)

    van der Wier, Gerda; Pas, Hendri H.; Jonkman, Marcel F.

    2010-01-01

    Pemphigus is a chronic mucocutaneous autoimmune bullous disease that is characterized by loss of cell-cell contact in skin and/or mucous membranes. Past research has successfully identified desmosomes as immunological targets and has demonstrated that acantholysis is initiated through direct binding of IgG. The exact mechanisms of acantholysis, however, are still missing. Experimental model systems have contributed considerably to today's knowledge and are still a favourite tool of research. In this paper we will describe to what extent human cell and tissue models represent the in vivo situation, for example, organ cultures of human skin, keratinocyte cultures, and human skin grafted on mice and, furthermore, how suitable they are to study the pathogenesis of pemphigus. Organ cultures closely mimic the architecture of the epidermis but are less suitable to answer posed biochemical questions. Cultured keratinocyte monolayers are convenient in this respect, but their desmosomal make-up in terms of adhesion molecules does not exactly reflect the in vivo situation. Reconstituted skin is a relatively new model that approaches organ culture. In models of human skin grafted on mice, acantholysis can be studied in actual human skin but now with all the advantages of an animal model. PMID:20585596

  8. Differential reduction of reactive oxygen species by human tissue ...

    Indian Academy of Sciences (India)

    Swati Paliwal

    2017-06-24

    Jun 24, 2017 ... MSCs are known to reduce increased oxidative stress levels in pathophysiological condi- ... AU, arbitrary units; BM, bone marrow; DP, dental pulp; MFI, mean .... terized based on the presence of all surface markers including.

  9. Adaptation of human adipose tissue to hypocaloric diet.

    Science.gov (United States)

    Rossmeislová, L; Mališová, L; Kračmerová, J; Štich, V

    2013-05-01

    Hypocaloric diet is a key component of the weight-reducing treatment of obesity and obesity-related disorders. Hypocaloric diets and the associated weight reduction promote improvement of metabolic profile of obese individuals. Among the mechanisms that underlie this beneficial metabolic outcome, the diet-induced modifications of morphological and functional characteristics of human adipose tissue (AT) are believed to have an important role. Prospective studies of hypocaloric weight-reducing dietary intervention demonstrate effects on adipocyte metabolism, namely lipolysis and lipogenesis, and associated changes of the adipocyte size. The endocrine function of AT, which involves cytokine and adipokine production by adipocytes, as well as by cells of stromavascular fraction, is also regulated by dietary intervention. Related inflammatory status of AT is modulated also as a consequence of the changes in recruitment of immune cells, mainly macrophages, in AT. Here, we give an overview of metabolic and endocrine modifications in human AT induced by a variety of hypocaloric diets.

  10. Culture medium modulates the behaviour of human dental pulp-derived cells: Technical Note

    Directory of Open Access Journals (Sweden)

    S Lopez-Cazaux

    2006-02-01

    Full Text Available In vitro approaches have extensively been developed to study reparative dentinogenesis. While dental pulp is a source of unidentified progenitors able to differentiate into odontoblast-like cells, we investigated the effect of two media; MEM (1.8mM Ca and 1mM Pi and RPMI 1640 (0.8mM Ca and 5mM Pi on the behaviour of human dental pulp cells. Our data indicate that MEM significantly increased cell proliferation and markedly enhanced the proportion of -smooth muscle actin positive cells, which represent a putative source of progenitors able to give rise to odontoblast-like cells. In addition, MEM strongly stimulated alkaline phosphatase activity and was found to induce expression of transcripts encoding dentin sialophosphoprotein, an odontoblastic marker, without affecting that of parathyroid hormone/parathyroid hormone related protein-receptor and osteonectin. In conclusion, these observations demonstrate that not only proliferation but also differentiation into odontoblast-like cells was induced by rich calcium and poor phosphate medium (MEM as compared to RPMI 1640. This study provides important data for the determination of the optimal culture conditions allowing odontoblast-like differentiation in human pulp cell culture.

  11. Phenolsulphotransferase in human tissue: radiochemical enzymatic assay and biochemical properties

    International Nuclear Information System (INIS)

    Anderson, R.J.; Weinshilboum, R.M.

    1980-01-01

    Phenolsulphotransferase (EC 2.8.2.1) (PST) is an important catecholamine and drug metabolizing enzyme. Optimal conditions have been determined for the accurate measurement of PST activity in the human platelet, human renal cortex, and human jejunum with a radiochemical microassay. 3-Methoxy-4-hydroxyphenylglycol (MHPG) and 35 S-3'-phosphoadenosine-5'-phosphosulfate ( 35 S-PAPS) were the substrates for the reaction. The apparent Michaelis-Menten (Ksub(m)) values for MHPG with platelet, renal cortex, and jejunum were 1.09, 0.46 and 1.16 mmol/l, respectively. Apparent Ksub(m) values for PAPS in the same tissues were 0.14, 0.13 and 0.21 μmol/l. The pH optimum of the reacton in all three tissues was approximately 6.2-6.8 with three different buffer systems. The coefficients of variation for the assay of platelet, renal cortex, and jejunal activities were 6.2%, 3.4% and 4.4%, respectively. Mean platelet PST activity in blood samples from 75 randomly selected adult subjects was 5.0 +- 1.72 mmol of MHPG sulfate formed per hour per mg of platelet protein (8.3 X 10 -5 +- 2.9 X 10 -5 μmol min -1 mg -1 , mean +- S.D.). There was a 5-fold intersubject variation in platelet PST activity within two standard deviations of the mean value. Experiments in which partially purified human erythrocyte PST was added to platelet, kidney and gut homogenates under these assay conditions provided evidence that endogenous PST inhibitors did not affect the observed enzyme activity. (Auth.)

  12. Human papillomavirus detection in paraffin-embedded colorectal cancer tissues.

    Science.gov (United States)

    Tanzi, Elisabetta; Bianchi, Silvia; Frati, Elena R; Amicizia, Daniela; Martinelli, Marianna; Bragazzi, Nicola L; Brisigotti, Maria Pia; Colzani, Daniela; Fasoli, Ester; Zehender, Gianguglielmo; Panatto, Donatella; Gasparini, Roberto

    2015-01-01

    Human papillomavirus (HPV) has a well-recognized aetiological role in the development of cervical cancer and other anogenital tumours. Recently, an association between colorectal cancer and HPV infection has been suggested, although this is still controversial. This study aimed at detecting and characterizing HPV infection in 57 paired biopsies from colorectal cancers and adjacent intact tissues using a degenerate PCR approach. All amplified fragments were genotyped by means of sequencing. Overall, HPV prevalence was 12.3 %. In particular, 15.8 % of tumour tissues and 8.8 % of non-cancerous tissue samples were HPV DNA-positive. Of these samples, 85.7 % were genotyped successfully, with 41.7 % of sequences identifying four genotypes of the HR (high oncogenic risk) clade Group 1; the remaining 58.3 % of HPV-genotyped specimens had an unclassified β-HPV. Examining additional cases and analysing whole genomes will help to outline the significance of these findings.

  13. Mechanical stimulation improves tissue-engineered human skeletal muscle

    Science.gov (United States)

    Powell, Courtney A.; Smiley, Beth L.; Mills, John; Vandenburgh, Herman H.

    2002-01-01

    Human bioartificial muscles (HBAMs) are tissue engineered by suspending muscle cells in collagen/MATRIGEL, casting in a silicone mold containing end attachment sites, and allowing the cells to differentiate for 8 to 16 days. The resulting HBAMs are representative of skeletal muscle in that they contain parallel arrays of postmitotic myofibers; however, they differ in many other morphological characteristics. To engineer improved HBAMs, i.e., more in vivo-like, we developed Mechanical Cell Stimulator (MCS) hardware to apply in vivo-like forces directly to the engineered tissue. A sensitive force transducer attached to the HBAM measured real-time, internally generated, as well as externally applied, forces. The muscle cells generated increasing internal forces during formation which were inhibitable with a cytoskeleton depolymerizer. Repetitive stretch/relaxation for 8 days increased the HBAM elasticity two- to threefold, mean myofiber diameter 12%, and myofiber area percent 40%. This system allows engineering of improved skeletal muscle analogs as well as a nondestructive method to determine passive force and viscoelastic properties of the resulting tissue.

  14. Modeling the behavior of human body tissues on penetration

    Science.gov (United States)

    Conci, A.; Brazil, A. L.; Popovici, D.; Jiga, G.; Lebon, F.

    2018-02-01

    Several procedures in medicine (such as anesthesia, injections, biopsies and percutaneous treatments) involve a needle insertion. Such procedures operate without vision of the internal involved areas. Physicians and anesthetists rely on manual (force and tactile) feedback to guide their movements, so a number of medical practice is strongly based on manual skill. In order to be expert in the execution of such procedures the medical students must practice a number of times, but before practice in a real patient they must be trained in some place and a virtual environment, using Virtual Reality (VR) or Augmented Reality (AR) is the best possible solution for such training. In a virtual environment the success of user practices is improved by the addition of force output using haptic device to improve the manual sensations in the interactions between user and computer. Haptic devices enable simulate the physical restriction of the diverse tissues and force reactions to movements of operator hands. The trainees can effectively "feel" the reactions to theirs movements and receive immediate feedback from the actions executed by them in the implemented environment. However, in order to implement such systems, the tissue reaction to penetration and cutting must be modeled. A proper model must emulate the physical sensations of the needle action in the skin, fat, muscle, and so one, as if it really done in a patient that is as they are holding a real needle and feeling each tissue resistance when inserting it through the body. For example an average force value for human skin puncture is 6.0 N, it is 2.0 N for subcutaneous fat tissue and 4.4 N for muscles: this difference of sensations to penetration of each layers trespassed by the needle makes possible to suppose the correct position inside the body. This work presents a model for tissues before and after the cutting that with proper assumptions of proprieties can model any part of human body. It was based on experiments

  15. The PAXgene(® tissue system preserves phosphoproteins in human tissue specimens and enables comprehensive protein biomarker research.

    Directory of Open Access Journals (Sweden)

    Sibylle Gündisch

    Full Text Available Precise quantitation of protein biomarkers in clinical tissue specimens is a prerequisite for accurate and effective diagnosis, prognosis, and personalized medicine. Although progress is being made, protein analysis from formalin-fixed and paraffin-embedded tissues is still challenging. In previous reports, we showed that the novel formalin-free tissue preservation technology, the PAXgene Tissue System, allows the extraction of intact and immunoreactive proteins from PAXgene-fixed and paraffin-embedded (PFPE tissues. In the current study, we focused on the analysis of phosphoproteins and the applicability of two-dimensional gel electrophoresis (2D-PAGE and enzyme-linked immunosorbent assay (ELISA to the analysis of a variety of malignant and non-malignant human tissues. Using western blot analysis, we found that phosphoproteins are quantitatively preserved in PFPE tissues, and signal intensities are comparable to that in paired, frozen tissues. Furthermore, proteins extracted from PFPE samples are suitable for 2D-PAGE and can be quantified by ELISA specific for denatured proteins. In summary, the PAXgene Tissue System reliably preserves phosphoproteins in human tissue samples, even after prolonged fixation or stabilization times, and is compatible with methods for protein analysis such as 2D-PAGE and ELISA. We conclude that the PAXgene Tissue System has the potential to serve as a versatile tissue fixative for modern pathology.

  16. Distribution of adenosine deaminase complexing protein (ADCP) in human tissues.

    Science.gov (United States)

    Dinjens, W N; ten Kate, J; van der Linden, E P; Wijnen, J T; Khan, P M; Bosman, F T

    1989-12-01

    The normal distribution of adenosine deaminase complexing protein (ADCP) in the human body was investigated quantitatively by ADCP-specific radioimmunoassay (RIA) and qualitatively by immunohistochemistry. In these studies we used a specific rabbit anti-human ADCP antiserum. In all 19 investigated tissues, except erythrocytes, ADCP was found by RIA in the soluble and membrane fractions. From all tissues the membrane fractions contained more ADCP (expressed per mg protein) than the soluble fractions. High membrane ADCP concentrations were found in skin, renal cortex, gastrointestinal tract, and prostate. Immunoperoxidase staining confirmed the predominant membrane-associated localization of the protein. In serous sweat glands, convoluted tubules of renal cortex, bile canaliculi, gastrointestinal tract, lung, pancreas, prostate gland, salivary gland, gallbladder, mammary gland, and uterus, ADCP immunoreactivity was found confined to the luminal membranes of the epithelial cells. These data demonstrate that ADCP is present predominantly in exocrine glands and absorptive epithelia. The localization of ADCP at the secretory or absorptive apex of the cells suggests that the function of ADCP is related to the secretory and/or absorptive process.

  17. Environment as reflected in human tissue and hair: a comparison

    International Nuclear Information System (INIS)

    Dale, I.M.; Lenihan, J.M.A.; Smith, H.

    1974-01-01

    This study looks at variations in trace metal content of a range of human tissues over a period of 10 years, extended comparison of metal concentrations in hair specimens over 200 years, the influence of geographical location on trace element levels in hair and nails and investigates groups of people with particular exposure problems. It is found that there has been little or no change in the concentration of some of the trace elements in human tissue over the past ten years. An extended survey of hair over the past 200 years shows a similar result. Investigation of trace element levels from widely separated localities also indicates little or no change in metal concentrations. It appears from these studies that man's contamination from his environment has remained fairly constant with respect to time and place. However it is shown in further studies that local pockets of significant exposure, e.g., particular professions, industry, agriculture and self-medication, do occur and certainly warrant close attention

  18. Hydrodynamic model for ultra-short pulse ablation of hard dental tissue

    Energy Technology Data Exchange (ETDEWEB)

    London, R.A.; Bailey, D.S.; Young, D.A.; Alley, W.E.; Feit, M.D.; Rubenchik, A.M. [Lawrence Livermore National Lab., CA (United States); Neev, J. [Beckman Laser Inst., Irvine, CA (United States)

    1996-02-29

    A computational model for the ablation of tooth enamel by ultra-short laser pulses is presented. The role of simulations using this model in designing and understanding laser drilling systems is discussed. Pulses of duration 300 fsec and intensity greater than 10{sup 12} W/cm{sup 2} are considered. Laser absorption proceeds via multi-photon initiated plasma mechanism. The hydrodynamic response is calculated with a finite difference method, using an equation of state constructed from thermodynamic functions including electronic, ion motion, and chemical binding terms. Results for the ablation efficiency are presented. An analytic model describing the ablation threshold and ablation depth is presented. Thermal coupling to the remaining tissue and long-time thermal conduction are calculated. Simulation results are compared to experimental measurements of the ablation efficiency. Desired improvements in the model are presented.

  19. Study and structural and chemical characterization of human dental smalt by electron microscopy; Estudio y caracterizacion estructural y quimico del esmalte dental humano por microscopia electronica

    Energy Technology Data Exchange (ETDEWEB)

    Belio R, I A; Reyes G, J [Instituto de Fisica, UNAM, A.P. 20-364, 01000 Mexico D.F. (Mexico)

    1998-07-01

    The study of human dental smalt has been subject to investigation for this methods with electron microscopy, electron diffraction, X-ray diffraction and image simulation programs have been used with the purpose to determine its chemical and structural characteristics of the organic and inorganic materials. This work has been held mainly for the characterization of hydroxyapatite (Ca){sub 10} (PO{sub 4}){sub 6} (OH{sub 4}){sub 2}, inorganic material which conforms the dental smalt in 97%, so observing its structural unity which is composed by the prisms and these by crystals and atoms. It was subsequently initiated the study of the organic material, with is precursor of itself. (Author)

  20. YAP regulates the expression of Hoxa1 and Hoxc13 in mouse and human oral and skin epithelial tissues.

    Science.gov (United States)

    Liu, Ming; Zhao, Shuangyun; Lin, Qingjie; Wang, Xiu-Ping

    2015-04-01

    Yes-associated protein (YAP) is a Hippo signaling transcriptional coactivator that plays pivotal roles in stem cell proliferation, organ size control, and tumor development. The downstream targets of YAP have been shown to be highly context dependent. In this study, we used the embryonic mouse tooth germ as a tool to search for the downstream targets of YAP in ectoderm-derived tissues. Yap deficiency in the dental epithelium resulted in a small tooth germ with reduced epithelial cell proliferation. We compared the gene expression profiles of embryonic day 14.5 (E14.5) Yap conditional knockout and YAP transgenic mouse tooth germs using transcriptome sequencing (RNA-Seq) and further confirmed the differentially expressed genes using real-time PCR and in situ hybridization. We found that YAP regulates the expression of Hoxa1 and Hoxc13 in oral and dental epithelial tissues as well as in the epidermis of skin during embryonic and adult stages. Sphere formation assay suggested that Hoxa1 and Hoxc13 are functionally involved in YAP-regulated epithelial progenitor cell proliferation, and chromatin immunoprecipitation (ChIP) assay implies that YAP may regulate Hoxa1 and Hoxc13 expression through TEAD transcription factors. These results provide mechanistic insights into abnormal YAP activities in mice and humans. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. [Cloning and characterization of genes differentially expressed in human dental pulp cells and gingival fibroblasts].

    Science.gov (United States)

    Wang, Zhong-dong; Wu, Ji-nan; Zhou, Lin; Ling, Jun-qi; Guo, Xi-min; Xiao, Ming-zhen; Zhu, Feng; Pu, Qin; Chai, Yu-bo; Zhao, Zhong-liang

    2007-02-01

    To study the biological properties of human dental pulp cells (HDPC) by cloning and analysis of genes differentially expressed in HDPC in comparison with human gingival fibroblasts (HGF). HDPC and HGF were cultured and identified by immunocytochemistry. HPDC and HGF subtractive cDNA library was established by PCR-based modified subtractive hybridization, genes differentially expressed by HPDC were cloned, sequenced and compared to find homogeneous sequence in GenBank by BLAST. Cloning and sequencing analysis indicate 12 genes differentially expressed were obtained, in which two were unknown genes. Among the 10 known genes, 4 were related to signal transduction, 2 were related to trans-membrane transportation (both cell membrane and nuclear membrane), and 2 were related to RNA splicing mechanisms. The biological properties of HPDC are determined by the differential expression of some genes and the growth and differentiation of HPDC are associated to the dynamic protein synthesis and secretion activities of the cell.

  2. Dental hard tissue modification and removal using sealed transverse excited atmospheric-pressure lasers operating at lambda=9.6 and 10.6 um

    Science.gov (United States)

    Fried, Daniel; Ragadio, Jerome N.; Akrivou, Maria; Featherstone, John D.; Murray, Michael W.; Dickenson, Kevin M.

    2001-04-01

    Pulsed CO2 lasers have been shown to be effective for both removal and modification of dental hard tissue for the treatment of dental caries. In this study, sealed transverse excited atmospheric pressure (TEA) laser systems optimally tuned to the highly absorbed 9.6 micrometers wavelength were investigated for application on dental hard tissue. Conventional TEA lasers produce an initial high energy spike at the beginning of the laser pulse of submicrosecond duration followed by a long tail of about 1 - 4 microsecond(s) . The pulse duration is well matched to the 1 - 2 microsecond(s) thermal relaxation time of the deposited laser energy at 9.6 micrometers and effectively heats the enamel to the temperatures required for surface modification at absorbed fluences of less than 0.5 J/cm2. Thus, the heat deposition in the tooth and the corresponding risk of pulpal necrosis from excessive heat accumulation is minimized. At higher fluences, the high peak power of the laser pulse rapidly initiates a plasma that markedly reduces the ablation rate and efficiency, severely limiting applicability for hard tissue ablation. By lengthening the laser pulse to reduce the energy distributed in the initial high energy spike, the plasma threshold can be raised sufficiently to increase the ablation rate by an order of magnitude. This results in a practical and efficient CO2 laser system for caries ablation and surface modification.

  3. Dental hard tissue modification and removal using sealed TEA lasers operating at λ=9.6 and 10.6 μm

    Science.gov (United States)

    Fried, Daniel; Murray, Michael W.; Featherstone, John D. B.; Akrivou, Maria; Dickenson, Kevin M.; Duhn, Clifford W.; Ojeda, Orlando P.

    1999-05-01

    Pulsed CO2 lasers have been shown to be effective for both removal and modification of dental hard tissue for the treatment of dental caries. In this study, sealed TEA laser systems optimally tuned to the highly absorbed 9.6 μm wavelength were investigated for application on dental hard tissue. Conventional TEA lasers produce a laser pulse wit a 100-200 ns gain switched spike followed by a long tail of about 1-4 μs in duration. the pulse duration is well matched to the 1-2 μs thermal relaxation time of the deposited laser energy at 9.6 μm and effectively heats the enamel to temperatures required for surface modification for caries prevention at absorbed fluences of less than 0.5 J/cm2. Thus, the heat deposition in the tooth and the corresponding risk, of pulpal necrosis form excessive heat accumulation is minimized. At higher fluences the high peak power of the gain-switched spike rapidly initiates a plasma that markedly reduces the ablation rate and efficiency, severely limiting applicability for hard tissue ablation. By slightly stretching the pulse to reduce the energy distributed in the initial 100-200 ns of the laser pulse, the plasma threshold can be raised sufficiently to increase the ablation rate by an order of magnitude. This results in a practical and efficient CO2 laser system for caries ablation and surface modification.

  4. Scanning Electron Microscope (SEM Evaluation of the Interface between a Nanostructured Calcium-Incorporated Dental Implant Surface and the Human Bone

    Directory of Open Access Journals (Sweden)

    Francesco Mangano

    2017-12-01

    Full Text Available Purpose. The aim of this scanning electron microscope (SEM study was to investigate the interface between the bone and a novel nanostructured calcium-incorporated dental implant surface in humans. Methods. A dental implant (Anyridge®, Megagen Implant Co., Gyeongbuk, South Korea with a nanostructured calcium-incorporated surface (Xpeed®, Megagen Implant Co., Gyeongbuk, South Korea, which had been placed a month earlier in a fully healed site of the posterior maxilla (#14 of a 48-year-old female patient, and which had been subjected to immediate functional loading, was removed after a traumatic injury. Despite the violent trauma that caused mobilization of the fixture, its surface appeared to be covered by a firmly attached, intact tissue; therefore, it was subjected to SEM examination. The implant surface of an unused nanostructured calcium-incorporated implant was also observed under SEM, as control. Results. The surface of the unused implant showed a highly-structured texture, carved by irregular, multi-scale hollows reminiscent of a fractal structure. It appeared perfectly clean and devoid of any contamination. The human specimen showed trabecular bone firmly anchored to the implant surface, bridging the screw threads and filling the spaces among them. Conclusions. Within the limits of this human histological report, the sample analyzed showed that the nanostructured calcium-incorporated surface was covered by new bone, one month after placement in the posterior maxilla, under an immediate functional loading protocol.

  5. Human sciences in the first semester of the dental undergraduate course at the Karolinska Institute, Stockholm.

    Science.gov (United States)

    Röding, K

    1999-08-01

    The first 9 weeks of the dental undergraduate education at the Karolinska Institutet comprises a transition course, designed to introduce students to university studies leading to professional qualifications in patient-related health sciences. 1 week has been set aside for the theme Man and Society, highlighting the importance of the human sciences for the development of behavioural skills necessary for achieving professionalism and a holistic patient concept. Some essential ethical questions are addressed: intercultural communication, empathy, professional demeanour and the development of professional competence, and group dynamics. In this context, more specific subjects are considered, such as the emergence of the multicultural society and its implications for health services, interpersonal skills and patient communication in the health and medical fields. There are several reasons for including this theme, which forms the basis for the ethical and communicative strands throughout the entire curriculum. As 30-40% of freshmen dental students are of non-Swedish origin, it is essential to include cultural awareness seminars. Another reason is that within the EU, cultural and communicative skills are recognised proficiencies for health professionals; it is also acknowledged that effective delivery of health care may be impeded by misunderstandings in communication and conflict in ethical beliefs. Group discussions are scheduled during the week in order to allow the students to discuss their own experiences related to the theme. The students are also given a written assignment in relation to one of the seminars; the report is assessed as a part of the examination. The week is concluded by a plenum discussion summarising the group discussions. To date, 4 course evaluations, with a response rate of 92.5%, show that 97.3% of the students were positive to the theme as a whole or to specific seminars held during the week, especially intercultural communication, ethics and

  6. miRNA-720 controls stem cell phenotype, proliferation and differentiation of human dental pulp cells.

    Directory of Open Access Journals (Sweden)

    Emilio Satoshi Hara

    Full Text Available Dental pulp cells (DPCs are known to be enriched in stem/progenitor cells but not well characterized yet. Small non-coding microRNAs (miRNAs have been identified to control protein translation, mRNA stability and transcription, and have been reported to play important roles in stem cell biology, related to cell reprogramming, maintenance of stemness and regulation of cell differentiation. In order to characterize dental pulp stem/progenitor cells and its mechanism of differentiation, we herein sorted stem-cell-enriched side population (SP cells from human DPCs and periodontal ligament cells (PDLCs, and performed a locked nucleic acid (LNA-based miRNA array. As a result, miR-720 was highly expressed in the differentiated main population (MP cells compared to that in SP cells. In silico analysis and a reporter assay showed that miR-720 targets the stem cell marker NANOG, indicating that miR-720 could promote differentiation of dental pulp stem/progenitor cells by repressing NANOG. Indeed, gain-and loss-of-function analyses showed that miR-720 controls NANOG transcript and protein levels. Moreover, transfection of miR-720 significantly decreased the number of cells positive for the early stem cell marker SSEA-4. Concomitantly, mRNA levels of DNA methyltransferases (DNMTs, which are known to play crucial factors during stem cell differentiation, were also increased by miR-720 through unknown mechanism. Finally, miR-720 decreased DPC proliferation as determined by immunocytochemical analysis against ki-67, and promoted odontogenic differentiation as demonstrated by alizarin red staining, as well as alkaline phosphatase and osteopontin mRNA levels. Our findings identify miR-720 as a novel miRNA regulating the differentiation of DPCs.

  7. The different expression profiles of microRNAs in elderly and young human dental pulp and the role of miR-433 in human dental pulp cells.

    Science.gov (United States)

    Wang, Kejing; Li, Li; Wu, Junjun; Qiu, Qin; Zhou, Fengjuan; Wu, Hongkun

    2015-03-01

    As a kind of endogenous noncoding small RNA, MicroRNA (miRNA) plays important roles of regulation to various physiological functions, while its affections on senescence of human dental pulp cell (HDPCs) are still unknown. Thus, we identified the senescence-associated miRNAs in HDPCs by microarray analysis, predicted their targets and regulatory signaling pathway by gene ontology and Kyoto encyclopedia of genes and genomes pathway database analysis. After validated, the senescence-associated miRNAs' expression level was up- and down-regulated using lentivirus package and cell transfection to find its role in HDPCs' morphology, proliferation, apoptosis, and mineralization. The results showed 27 miRNAs differentially expressed at least 1.5-fold, of which 16 were up-regulated and 11 down-regulated, the function of their targets was mainly focused on signal transduction, cell proliferation, apoptosis, and transcription regulation. According to the change fold, we speculated that miR-433 could be one of the vital senescence-associated miRNAs of HDPCs and found its target (GRB2), validated that miR-433 could negatively regulate GRB2 and the RAS-MAPK signaling pathway, leading to the decline of proliferation and mineralization ability of HDPCs and the acceleration of cell apoptosis, suggesting the regulation of miR-433 might be the potential target to promote repair and regeneration of HDPCs in the elderly. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. In Vivo Articular Cartilage Regeneration Using Human Dental Pulp Stem Cells Cultured in an Alginate Scaffold: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Manuel Mata

    2017-01-01

    Full Text Available Osteoarthritis is an inflammatory disease in which all joint-related elements, articular cartilage in particular, are affected. The poor regeneration capacity of this tissue together with the lack of pharmacological treatment has led to the development of regenerative medicine methodologies including microfracture and autologous chondrocyte implantation (ACI. The effectiveness of ACI has been shown in vitro and in vivo, but the use of other cell types, including bone marrow and adipose-derived mesenchymal stem cells, is necessary because of the poor proliferation rate of isolated articular chondrocytes. In this investigation, we assessed the chondrogenic ability of human dental pulp stem cells (hDPSCs to regenerate cartilage in vitro and in vivo. hDPSCs and primary isolated rabbit chondrocytes were cultured in chondrogenic culture medium and found to express collagen II and aggrecan. Both cell types were cultured in 3% alginate hydrogels and implanted in a rabbit model of cartilage damage. Three months after surgery, significant cartilage regeneration was observed, particularly in the animals implanted with hDPSCs. Although the results presented here are preliminary, they suggest that hDPSCs may be useful for regeneration of articular cartilage.

  9. In Vivo Articular Cartilage Regeneration Using Human Dental Pulp Stem Cells Cultured in an Alginate Scaffold: A Preliminary Study.

    Science.gov (United States)

    Mata, Manuel; Milian, Lara; Oliver, Maria; Zurriaga, Javier; Sancho-Tello, Maria; de Llano, Jose Javier Martin; Carda, Carmen

    2017-01-01

    Osteoarthritis is an inflammatory disease in which all joint-related elements, articular cartilage in particular, are affected. The poor regeneration capacity of this tissue together with the lack of pharmacological treatment has led to the development of regenerative medicine methodologies including microfracture and autologous chondrocyte implantation (ACI). The effectiveness of ACI has been shown in vitro and in vivo , but the use of other cell types, including bone marrow and adipose-derived mesenchymal stem cells, is necessary because of the poor proliferation rate of isolated articular chondrocytes. In this investigation, we assessed the chondrogenic ability of human dental pulp stem cells (hDPSCs) to regenerate cartilage in vitro and in vivo . hDPSCs and primary isolated rabbit chondrocytes were cultured in chondrogenic culture medium and found to express collagen II and aggrecan. Both cell types were cultured in 3% alginate hydrogels and implanted in a rabbit model of cartilage damage. Three months after surgery, significant cartilage regeneration was observed, particularly in the animals implanted with hDPSCs. Although the results presented here are preliminary, they suggest that hDPSCs may be useful for regeneration of articular cartilage.

  10. Gene expression change in human dental pulp cells exposed to a low-level toxic concentration of triethylene glycol dimethacrylate: an RNA-seq analysis.

    Science.gov (United States)

    Cho, Sung-Geun; Lee, Jin-Woo; Heo, Jung Sun; Kim, Sun-Young

    2014-09-01

    Dental composite resin restoration for defective tooth may lead unpolymerized resin monomers to be leached into dental pulp tissue. The aim of this study was to investigate the early gene expression change over time of human dental pulp cells (HDPCs) treated with a low-level toxic concentration of Triethylene Glycol Dimethacrylate (TEGDMA), a common dental resin monomer, by adopting the novel high-throughput transcriptome analysis of RNA-seq. The low-level toxic concentration of TEGDMA was determined through MTT assays with serially diluted concentrations. After the HDPCs were exposed to TEGDMA for 6, 12, 24 or 48 hr, the total RNA of the samples was prepared for RNA-seq. qRT-PCR for several genes was performed for validation of RNA-seq results. In the treated group, 1280 genes were differentially expressed compared with the control group. Five patterns of time-series gene expression profiles were identified through k-means clustering analysis. Angiogenesis, cell adhesion and migration, extracellular matrix organization, response to extracellular stimulus, inflammatory response and mineralization-related process were major gene ontology terms in functional annotation clustering. HMOX1, OSGIN1, SMN2, SRXN1 AKR1C1, SPP1 and TOMM40L were highly up-regulated genes, and WRAP53 and CCL2 were highly down-regulated genes over time. qRT-PCR for several genes exhibited a high level of agreement with RNA-seq. TEGDMA induced the HDPCs to show massive and dynamic gene expression changes over time. The previously suggested toxic mechanism of TEGDMA was not only verified, but new genes whose functions have yet to be determined were also found. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  11. MicroCT Scan in paleobiology: application to the study of dental tissues

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, M.; Casali, F. E-mail: casali@bo.infn.it; Romani, D.; Bondioli, L.; Macchiarelli, R.; Rook, L

    2004-01-01

    State of the art in paleoanthropological and paleoprimatological research foresees the use of advanced non-destructive investigative approaches. Microcomputed tomography (microCT) is a fundamental tool, since it offers the opportunity to get high quality morphological information with high spatial resolution. We carried out the set-up of an experimental microCT system able to examine paleobiological samples. The equipment can operate on small objects (size up to 3 cm) with a nominal spatial resolution of 30 {mu}m, allowing their 3D volume reconstruction and morphometric analysis. This approach represents a forefront technique in paleobiological studies, successfully employed only in a limited number of advanced research centers. A specific program of microCT analysis has been planned on a sample of human and non-human fossil primate dentitions, in order to assess the specific nature of a number of tooth lesions (e.g. caries versus abrasion). This currently in progress experimental activity represents the first step for the set-up of a research center specifically devoted to the realization of advanced studies in the field of archaeo-paleobiology.

  12. Adenovirus-mediated transfer of hepatocyte growth factor gene to human dental pulp stem cells under good manufacturing practice improves their potential for periodontal regeneration in swine.

    Science.gov (United States)

    Cao, Yu; Liu, Zhenhai; Xie, Yilin; Hu, Jingchao; Wang, Hua; Fan, Zhipeng; Zhang, Chunmei; Wang, Jingsong; Wu, Chu-Tse; Wang, Songlin

    2015-12-15

    Periodontitis is one of the most widespread infectious diseases in humans. We previously promoted significant periodontal tissue regeneration in swine models with the transplantation of autologous periodontal ligament stem cells (PDLSCs) and PDLSC sheet. We also promoted periodontal tissue regeneration in a rat model with a local injection of allogeneic bone marrow mesenchymal stem cells. The purpose of the present study is to investigate the roles of the hepatocyte growth factor (HGF) and human dental pulp stem cells (DPSCs) in periodontal tissue regeneration in swine. In the present study, we transferred an adenovirus that carried HGF gene into human DPSCs (HGF-hDPSCs) under good manufacturing practice (GMP) conditions. These cells were then transplanted into a swine model for periodontal regeneration. Twenty miniature pigs were used to generate periodontitis with bone defect of 5 mm in width, 7 mm in length, and 3 mm in depth. After 12 weeks, clinical, radiological, quantitative and histological assessment of regenerated periodontal tissues was performed to compare periodontal regeneration in swine treated with cell implantation. Our study showed that injecting HGF-hDPSCs into this large animal model could significantly improve periodontal bone regeneration and soft tissue healing. A hDPSC or HGF-hDPSC sheet showed superior periodontal tissue regeneration compared to the injection of dissociated cells. However, the sheets required surgical placement; thus, they were suitable for surgically-managed periodontitis treatments. The adenovirus-mediated transfer of the HGF gene markedly decreased hDPSC apoptosis in a hypoxic environment or in serum-free medium, and it increased blood vessel regeneration. This study indicated that HGF-hDPSCs produced under GMP conditions significantly improved periodontal bone regeneration in swine; thus, this method represents a potential clinical application for periodontal regeneration.

  13. Genotoxic and cytotoxic effects of different types of dental cement on normal cultured human lymphocytes.

    Science.gov (United States)

    Bakopoulou, A; Mourelatos, D; Tsiftsoglou, A S; Giassin, N P; Mioglou, E; Garefis, P

    2009-01-31

    In this study we have investigated the genotoxic and cytotoxic effects of eluates derived from different types of commercially available dental cements, including glass ionomer cements (GICs) (Ketac Cem/3M ESPE and GC Fuji I/GC Corp), resin-modified glass ionomer cements (RM-GICs) (RelyX Luting/3M ESPE and Vitrebond/3M ESPE) and dual-cure resin cements (RCs) (Variolink II/ Ivoclar-Vivadent and Panavia F 2.0/Kuraray) on normal cultured human lymphocytes. Lymphocyte primary cultures obtained from blood samples of three healthy donors were exposed to serial dilutions of eluates derived from specimens of each material tested. Metaphases were induced with phytohaemagglutinin, collected after 72h treatment by use of colchicine and stained according to the fluorescence plus giemsa (FPG) procedure. Preparations were scored for sister chromatid exchange (SCE) and chromosomal aberrations (CAs), while the proliferation rate index (PRI) was also calculated. Our results show that eluates derived from the RM-GICs and RCs caused severe genotoxic effects by significantly increasing the frequencies of SCEs and CAs in cultures of peripheral blood lymphocytes and by decreasing the relevant PRI values in a dose-dependent manner, whereas the two GICs caused only minor cytogenetic effects. Eluates of the two RM-GICs (Vitrebond and RelyX) were also very cytotoxic, as the first serial dilutions of both materials caused a complete mitotic arrest in lymphocyte cultures. Overall, the degree of genotoxicity and cytotoxicity caused by dental cements decreased as follows: Viterbond>Rely X>Panavia F 2.0>Variolink II>Ketac Cem=GC Fuji I. These results indicate that different types of dental cement differ extensively in their genotoxic and cytotoxic potential and their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair. Although these results cannot be directly extrapolated to the clinical situation, the potential occurrence of adverse effects caused by the

  14. Dental and Medical Students' Use and Perceptions of Learning Resources in a Human Physiology Course.

    Science.gov (United States)

    Tain, Monica; Schwartzstein, Richard; Friedland, Bernard; Park, Sang E

    2017-09-01

    The aim of this study was to determine the use and perceived utility of various learning resources available during the first-year Integrated Human Physiology course at the dental and medical schools at Harvard University. Dental and medical students of the Class of 2018 were surveyed anonymously online in 2015 regarding their use of 29 learning resources in this combined course. The learning resources had been grouped into four categories to discern frequency of use and perceived usefulness among the categories. The survey was distributed to 169 students, and 73 responded for a response rate of 43.2%. There was no significant difference among the learning resource categories in frequency of use; however, there was a statistically significant difference among categories in students' perceptions of usefulness. No correlation was found between frequency of use and perceived usefulness of each category. Students seemingly were not choosing the most useful resources for them. These results suggest that, in the current educational environment, where new technologies and self-directed learning are highly sought after, there remains a need for instructor-guided learning.

  15. Alteration of microRNA expression of human dental pulp cells during odontogenic differentiation.

    Science.gov (United States)

    Gong, Qimei; Wang, Runfu; Jiang, Hongwei; Lin, Zhengmei; Ling, Junqi

    2012-10-01

    MicroRNAs (miRNAs) play momentous roles in various biological processes including cell differentiation. However, little is known about the role of miRNAs in human dental pulp cells (hDPCs) during odontogenic differentiation. The aims of this study were to investigate the expression of miRNAs in the primary culture of hDPCs when incubated in odontogenic medium. The potential characteristics of hDPCs were investigated by miRNA microarray and real-time reverse transcriptase polymerase chain reaction. Bioinformatics (ie, target prediction, Gene Ontology analysis, and Kyoto Encyclopedia of Genes and Genomes mapping tools) were applied for predicting the complementary target genes of miRNAs and their biological functions. A total of 22 miRNAs were differentially expressed in which 12 miRNAs up-regulated and 10 miRNAs down-regulated in differentiated hDPCs compared with the control. The target genes of differential miRNAs were predicted to associate with several biological functions and signaling pathways including the mitogen-activated protein kinase (MAPK) and the Wnt signaling pathway. The differential expression miRNAs may be involved in governing hDPC odontogenic differentiation, thus contributing to the future investigations of regulatory mechanisms in reparative dentin formation and dental pulp regeneration. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. TET1 knockdown inhibits the odontogenic differentiation potential of human dental pulp cells.

    Science.gov (United States)

    Rao, Li-Jia; Yi, Bai-Cheng; Li, Qi-Meng; Xu, Qiong

    2016-06-30

    Human dental pulp cells (hDPCs) possess the capacity to differentiate into odontoblast-like cells and generate reparative dentin in response to exogenous stimuli or injury. Ten-eleven translocation 1 (TET1) is a novel DNA methyldioxygenase that plays an important role in the promotion of DNA demethylation and transcriptional regulation in several cell lines. However, the role of TET1 in the biological functions of hDPCs is unknown. To investigate the effect of TET1 on the proliferation and odontogenic differentiation potential of hDPCs, a recombinant shRNA lentiviral vector was used to knock down TET1 expression in hDPCs. Following TET1 knockdown, TET1 was significantly downregulated at both the mRNA and protein levels. Proliferation of the hDPCs was suppressed in the TET1 knockdown groups. Alkaline phosphatase activity, the formation of mineralized nodules, and the expression levels of DSPP and DMP1 were all reduced in the TET1-knockdown hDPCs undergoing odontogenic differentiation. Based on these results, we concluded that TET1 knockdown can prevent the proliferation and odontogenic differentiation of hDPCs, which suggests that TET1 may play an important role in dental pulp repair and regeneration.

  17. Dental erosion in archaeological human remains: A critical review of literature and proposal of a differential diagnosis protocol.

    Science.gov (United States)

    Coupal, Isabelle; Sołtysiak, Arkadiusz

    2017-12-01

    Although studies of dental wear on archaeological human remains have largely focused on mechanical wear (attrition and abrasion) in the past, chemical wear (erosion) is being increasingly identified as a separate form of wear. This paper aims to review the current state of research and to develop a protocol that may be universally used by biorchaeologists to specifically identify dental erosion. A critical review of literature has been done in order to highlight the issues related to diagnosis of dental erosion in archaeological human remains. The bodies of work based on the analysis of both modern and archaeological dentitions raise their separate problems. In addition to a need to re-evaluate symptoms of dental erosion, notably dentin 'cupping', it is apparent that no specific protocol is adapted from medical to archaeological sciences. Authors rather rely on tooth wear indices and photographs of modern clinical cases for diagnosis. Furthermore, the diagenetic chemical alternation has rarely been considered as a bias. Here we suggest a three-step protocol: the primary method is the microscopic identification of dental erosion by SEM, followed by the exclusion of taphonomic aetiology on surrounding bone and soil pH analysis. Archaeologists should also explore possible causative agents of wear using archaeological and historic knowledge about the population being analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Composition of Mineral Produced by Dental Mesenchymal Stem Cells.

    Science.gov (United States)

    Volponi, A A; Gentleman, E; Fatscher, R; Pang, Y W Y; Gentleman, M M; Sharpe, P T

    2015-11-01

    Mesenchymal stem cells isolated from different dental tissues have been described to have osteogenic/odontogenic-like differentiation capacity, but little attention has been paid to the biochemical composition of the material that each produces. Here, we used Raman spectroscopy to analyze the mineralized materials produced in vitro by different dental cell populations, and we compared them with the biochemical composition of native dental tissues. We show that different dental stem cell populations produce materials that differ in their mineral and matrix composition and that these differ from those of native dental tissues. In vitro, BCMP (bone chip mass population), SCAP (stem cells from apical papilla), and SHED (stem cells from human-exfoliated deciduous teeth) cells produce a more highly mineralized matrix when compared with that produced by PDL (periodontal ligament), DPA (dental pulp adult), and GF (gingival fibroblast) cells. Principal component analyses of Raman spectra further demonstrated that the crystallinity and carbonate substitution environments in the material produced by each cell type varied, with DPA cells, for example, producing a more carbonate-substituted mineral and with SCAP, SHED, and GF cells creating a less crystalline material when compared with other dental stem cells and native tissues. These variations in mineral composition reveal intrinsic differences in the various cell populations, which may in turn affect their specific clinical applications. © International & American Associations for Dental Research 2015.

  19. Functionalized scaffolds to control dental pulp stem cell fate

    Science.gov (United States)

    Piva, Evandro; Silva, Adriana F.; Nör, Jacques E.

    2014-01-01

    Emerging understanding about interactions between stem cells, scaffolds and morphogenic factors has accelerated translational research in the field of dental pulp tissue engineering. Dental pulp stem cells constitute a sub-population of cells endowed with self-renewal and multipotency. Dental pulp stem cells seeded in biodegradable scaffolds and exposed to dentin-derived morphogenic signals give rise to a pulp-like tissue capable of generating new dentin. Notably, dentin-derived proteins are sufficient to induce dental pulp stem cell differentiation into odontoblasts. Ongoing work is focused on developing ways of mobilizing dentin-derived proteins and disinfecting the root canal of necrotic teeth without compromising the morphogenic potential of these signaling molecules. On the other hand, dentin by itself does not appear to be capable of inducing endothelial differentiation of dental pulp stem cells, despite the well known presence of angiogenic factors in dentin. This is particularly relevant in the context of dental pulp tissue engineering in full root canals, where access to blood supply is limited to the apical foramina. To address this challenge, scientists are looking at ways to use the scaffold as a controlled release device for angiogenic factors. The aim of this manuscript is to present and discuss current strategies to functionalize injectable scaffolds and customize them for dental pulp tissue engineering. The long-term goal of this work is to develop stem cell-based therapies that enable the engineering of functional dental pulps capable of generating new tubular dentin in humans. PMID:24698691

  20. MicroRNA expression variability in human cervical tissues.

    Directory of Open Access Journals (Sweden)

    Patrícia M Pereira

    Full Text Available MicroRNAs (miRNAs are short (approximately 22 nt non-coding regulatory RNAs that control gene expression at the post-transcriptional level. Deregulation of miRNA expression has been discovered in a wide variety of tumours and it is now clear that they contribute to cancer development and progression. Cervical cancer is one of the most common cancers in women worldwide and there is a strong need for a non-invasive, fast and efficient method to diagnose the disease. We investigated miRNA expression profiles in cervical cancer using a microarray platform containing probes for mature miRNAs. We have evaluated miRNA expression profiles of a heterogeneous set of cervical tissues from 25 different patients. This set included 19 normal cervical tissues, 4 squamous cell carcinoma, 5 high-grade squamous intraepithelial lesion (HSIL and 9 low-grade squamous intraepithelial lesion (LSIL samples. We observed high variability in miRNA expression especially among normal cervical samples, which prevented us from obtaining a unique miRNA expression signature for this tumour type. However, deregulated miRNAs were identified in malignant and pre-malignant cervical tissues after tackling the high expression variability observed. We were also able to identify putative target genes of relevant candidate miRNAs. Our results show that miRNA expression shows natural variability among human samples, which complicates miRNA data profiling analysis. However, such expression noise can be filtered and does not prevent the identification of deregulated miRNAs that play a role in the malignant transformation of cervical squamous cells. Deregulated miRNAs highlight new candidate gene targets allowing for a better understanding of the molecular mechanism underlying the development of this tumour type.

  1. Photobiomodulation in human muscle tissue: an advantage in sports performance?

    Science.gov (United States)

    Ferraresi, Cleber; Huang, Ying-Ying; Hamblin, Michael R

    2016-12-01

    Photobiomodulation (PBM) describes the use of red or near-infrared (NIR) light to stimulate, heal, and regenerate damaged tissue. Both preconditioning (light delivered to muscles before exercise) and PBM applied after exercise can increase sports performance in athletes. This review covers the effects of PBM on human muscle tissue in clinical trials in volunteers related to sports performance and in athletes. The parameters used were categorized into those with positive effects or no effects on muscle performance and recovery. Randomized controlled trials and case-control studies in both healthy trained and untrained participants, and elite athletes were retrieved from MEDLINE up to 2016. Performance metrics included fatigue, number of repetitions, torque, hypertrophy; measures of muscle damage and recovery such as creatine kinase and delayed onset muscle soreness. Searches retrieved 533 studies, of which 46 were included in the review (n = 1045 participants). Studies used single laser probes, cluster of laser diodes, LED clusters, mixed clusters (lasers and LEDs), and flexible LED arrays. Both red, NIR, and red/NIR mixtures were used. PBM can increase muscle mass gained after training, and decrease inflammation and oxidative stress in muscle biopsies. We raise the question of whether PBM should be permitted in athletic competition by international regulatory authorities. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Effects of fibroblast growth factor-2 on the expression and regulation of chemokines in human dental pulp cells.

    Science.gov (United States)

    Kim, Young-Suk; Min, Kyung-San; Jeong, Dong-Ho; Jang, Jun-Hyeog; Kim, Hae-Won; Kim, Eun-Cheol

    2010-11-01

    Fibroblast growth factor-2 (FGF-2) participates in both hematopoiesis and osteogenesis; however, the effects of FGF-2 on chemokines during odontoblastic differentiation have not been reported. This study investigated whether human dental pulp cells (HDPCs) treated with FGF-2 could express chemokines during differentiation into odontoblastic cells and sought to identify its underlying mechanism of action. To analyze differentiation, we measured alkaline phosphatase (ALP) activity, calcified nodule formation by alizarin red staining, and marker RNA (mRNA) expression by reverse-transcriptase polymerase chain reaction (RT-PCR). Expression of chemokines, such as interleukin-6 (IL-6), IL-8, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), and MIP-3α, were evaluated by RT-PCR. ALP activity, the mineralization, and mRNA expression for odontoblastic markers were enhanced by FGF-2 in HDPCs. FGF-2 also up-regulated the expression of IL-6, IL-8, MCP-1, MIP-1α, and MIP-3α mRNAs, which were attenuated by inhibitors of p38, ERK1/2 and p38 MAP kinases, protein kinase C, phosphoinositide-3 kinase, and NF-κB. Taken together, these data suggest that FGF-2 plays a role not only as a differentiation inducing factor in the injury repair processes of pulpal tissue but also as a positive regulator of chemokine expression, which may help in tissue engineering and pulp regeneration using HDPCs. However, the fate of odontoblastic or osteoblastic differentiation, effective local delivery for FGF-2, interaction of chemotatic and odontogenic factors, and other limitations will need to be overcome before a major modality for the treatment of pulp disease. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Control of proliferation and osteogenic differentiation of human dental-pulp-derived stem cells by distinct surface structures.

    Science.gov (United States)

    Kolind, K; Kraft, D; Bøggild, T; Duch, M; Lovmand, J; Pedersen, F S; Bindslev, D A; Bünger, C E; Foss, M; Besenbacher, F

    2014-02-01

    The ability to control the behavior of stem cells provides crucial benefits, for example, in tissue engineering and toxicity/drug screening, which utilize the stem cell's capacity to engineer new tissues for regenerative purposes and the testing of new drugs in vitro. Recently, surface topography has been shown to influence stem cell differentiation; however, general trends are often difficult to establish due to differences in length scales, surface chemistries and detailed surface topographies. Here we apply a highly versatile screening approach to analyze the interplay of surface topographical parameters on cell attachment, morphology, proliferation and osteogenic differentiation of human mesenchymal dental-pulp-derived stem cells (DPSCs) cultured with and without osteogenic differentiation factors in the medium (ODM). Increasing the inter-pillar gap size from 1 to 6 μm for surfaces with small pillar sizes of 1 and 2 μm resulted in decreased proliferation and in more elongated cells with long pseudopodial protrusions. The same alterations of pillar topography, up to an inter-pillar gap size of 4 μm, also resulted in enhanced mineralization of DPSCs cultured without ODM, while no significant trend was observed for DPSCs cultured with ODM. Generally, cells cultured without ODM had a larger deposition of osteogenic markers on structured surfaces relative to the unstructured surfaces than what was found when culturing with ODM. We conclude that the topographical design of biomaterials can be optimized for the regulation of DPSC differentiation and speculate that the inclusion of ODM alters the ability of the cells to sense surface topographical cues. These results are essential in order to transfer the use of this highly proliferative, easily accessible stem cell into the clinic for use in cell therapy and regenerative medicine. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. In vitro analysis of scaffold-free prevascularized microtissue spheroids containing human dental pulp cells and endothelial cells.

    Science.gov (United States)

    Dissanayaka, Waruna Lakmal; Zhu, Lifang; Hargreaves, Kenneth M; Jin, Lijian; Zhang, Chengfei

    2015-05-01

    Scaffolds often fail to mimic essential functions of the physiologic extracellular matrix (ECM) that regulates cell-cell communication in tissue microenvironments. The development of scaffold-free microtissues containing stem cell-derived ECM may serve as a successful alternative to the use of artificial scaffolds. The current study aimed to fabricate 3-dimensional microtissue spheroids of dental pulp cells (DPCs) prevascularized by human umbilical vein endothelial cells (HUVECs) and to characterize these scaffold-free spheroids for the in vitro formation of pulplike tissue constructs. Three-dimensional microtissue spheroids of DPC alone and DPC-HUVEC co-cultures were fabricated using agarose micro-molds. Cellular organization within the spheroids and cell viability (live/dead assay) were assessed at days 1, 7, and 14. Microtissue spheroids were allowed to self-assemble into macrotissues, induced for odontogenic differentiation (21 days), and examined for expression levels of osteo/odontogenic markers: alkaline phosphatase, bone sialoprotein and RUNX2 (Real-time PCR), mineralization (von-Kossa), and prevascularisation (immunohistochemistry for CD31). The DPC microtissue microenvironment supported HUVEC survival and capillary network formation in the absence of a scaffolding material and external angiogenic stimulation. Immunohistochemical staining for CD31 showed the capillary network formed by HUVECs did sustain-for a prolonged period-even after the microtissues transformed into a macrotissue. Induced, prevascularized macrotissues showed enhanced differentiation capacity compared with DPC alone macrotissues, as shown by higher osteo/odontogenic gene expression levels and mineralization. These findings provide insight into the complex intercellular cross talk occurring between DPCs and HUVECs in the context of angiogenesis and pulp regeneration and highlight the significance of developing a favorable 3-dimensional microenvironment that can, in turn, contribute

  5. Variation in tissue outcome of ovine and human engineered heart valve constructs : relevance for tissue engineering

    NARCIS (Netherlands)

    Geemen, van D.; Driessen - Mol, A.; Grootzwagers, L.G.M.; Soekhradj - Soechit, R.S.; Riem Vis, P.W.; Baaijens, F.P.T.; Bouten, C.V.C.

    AIM: Clinical application of tissue engineered heart valves requires precise control of the tissue culture process to predict tissue composition and mechanical properties prior to implantation, and to understand the variation in tissue outcome. To this end we investigated cellular phenotype and

  6. Tooth for a tooth: Tissue engineering made easy at dental chairside

    Directory of Open Access Journals (Sweden)

    Vandana Kharidhi Laxman

    2017-01-01

    Full Text Available Background: Stem cells are unspecialized, multipotent cells which can differentiate into different cell types. The human periodontal ligament encloses subpopulation of Periodontal Ligament Stem Cells (PDLSCs which are able to regenerate the periodontium by differentiating into various cells of PDL. Literature have shown the promising results of periodontal regeneration by exvivo cultured transplantation of PDLSCs into the osseous defects. Methods: Based on current literature on use of ex vivo culture and associated problems, a novel technique is being presented , Stem cell application in periodontal regeneration (SAI-PRT which uses autologous PDLSCs along with its niche adhering to extracted tooth root for direct application using gelatin sponge as scaffold in regeneration of intrabony periodontal defect bypassing ex-vivo culture. Results: The cases initiated under SAI-PRT protocol, and have shown excellent clinical and radiographic improvement in intrabony defect using direct transplant of autologous PDLSCs . Conclusions: SAI-PRT can be used for the treatment of periodontal osseous defects at chair side.

  7. Human tissue legislation in South Africa: Focus on stem cell ...

    African Journals Online (AJOL)

    2015-08-04

    Aug 4, 2015 ... to assess the use of stem cells in the treatment of heart disease. Likewise ... always needs to be informed in the broadest sense with the patient .... progenitor cells) from a living person for medical or dental purposes requires ...

  8. Modern views on the pathogenesis of hard dental tissues and periodontium lesions and means of their treatment in children with chronic diseases of the gastrointestinal tract

    Directory of Open Access Journals (Sweden)

    Krupey V.Y.

    2014-09-01

    Full Text Available Changes in the mouth covity often reflect regularities of pathogenesis of a number of disease states, and primarily from the digestive tract. Therefore, the purpose of the study was to clarify pathogenesis of certain lesions of hard dental tissues and periodontal tissues in children with chronic diseases of the gastrointestinal tract and development of schemes for their treatment. The study observed 441 children aged from 7 to 15 years with dental caries and generalized chronic catarrhal gingivitis on the background of chronic gastritis and duodenitis, duodenal ulcer and malabsorption syndrome. All the children were divided into 2 groups - basic and comparison one. The study identified the most dan¬gerous and little-known way of pathogenesis, which passes through the general processes of reducing the production of various proteins (immune system and antiseptics, is a violation of the general and local resistance and, ultimately, mineral metabolism. Such disorders impair complete mineralization of tooth enamel, reduce optimal composition and properties of saliva stimulating glycolysis processes in oral cavity. Prevention of dental caries and generalized chronic catarrhal gingivitis in children with chronic pathology of the gastrointestinal tract is based on the use of developed therapeutic and prophylactic complex, which includes mucosal gel Kvertulin, probiotic Latsidofil and drug Calcium D.

  9. Neuromandibular integration in humans and chimpanzees: Implications for dental and mandibular reduction in Homo.

    Science.gov (United States)

    Veneziano, Alessio; Meloro, Carlo; Irish, Joel D; Stringer, Chris; Profico, Antonio; De Groote, Isabelle

    2018-05-08

    Although the evolution of the hominin masticatory apparatus has been linked to diet and food processing, the physical connection between neurocranium and lower jaw suggests a role of encephalization in the trend of dental and mandibular reduction. Here, the hypothesis that tooth size and mandibular robusticity are influenced by morphological changes in the neurocranium was tested. Three-dimensional landmarks, alveolar lengths, and mandibular robusticity data were recorded on a sample of chimpanzee and human skulls. The morphological integration between the neurocranium and the lower jaw was analyzed by means of Singular Warps Analysis. Redundancy Analysis was performed to understand if the pattern of neuromandibular integration affects tooth size and mandibular robusticity. There is significant morphological covariation between neurocranium and lower jaw in both chimpanzees and humans. In humans, changes in the temporal fossa seem to produce alterations of the relative orientation of jaw parts, while the influence of similar neurocranial changes in chimpanzees are more localized. In both species, postcanine alveolar lengths and mandibular robusticity are associated with shape changes of the temporal fossa. The results of this study support the hypothesis that the neurocranium is able to affect the evolution and development of the lower jaw, although most likely through functional integration of mandible, teeth, and muscles within the masticatory apparatus. This study highlights the relative influence of structural constraints and adaptive factors in the evolution of the human skull. © 2018 Wiley Periodicals, Inc.

  10. Characterization and human gingival fibroblasts biocompatibility of hydroxyapatite/PMMA nanocomposites for provisional dental implant restoration

    Science.gov (United States)

    Zhang, Jingchao; Liao, Juan; Mo, Anchun; Li, Yubao; Li, Jidong; Wang, Xuejiang

    2008-11-01

    The aim of this study was to determine nHA/PMMA composites (H/P) in an optimal ratio with improved cytocompatibility as well as valid physical properties for provisional dental implant restoration. 20 wt.%, 30 wt.%, 40 wt.% and 50 wt.% H/P were developed and characterized using XPS, bending strength test and SEM. Human gingival fibroblasts cultured in extracts or directly on sample discs were investigated by fluorescent staining and MTT assay. Chemical integration in nHA/PMMA interface was indicated by XPS. Typical fusiform cells with adhesion spots were detected on H/P discs. MTT results also indicated higher cell viability in 30 wt.% and 40 wt.% H/P discs ( P provisional fixed crowns (PFC) is 0.4:1.

  11. Human Papilloma Virus in Retinoblastoma Tissues from Korean Patients

    Science.gov (United States)

    Ryoo, Na-Kyung; Kim, Ji-Eun; Kim, Namju; Lee, Min-Jeong; Khwarg, Sang-In

    2013-01-01

    Purpose Recent reports suggest the association of human papilloma virus (HPV) with retinoblastoma. This study was performed to elucidate whether HPV infection is related to retinoblastoma among Koreans. Methods A total of 54 cases diagnosed with retinoblastoma were enrolled from Seoul National University Children's Hospital and Seoul Metropolitan Government-Seoul National University Boramae Medical Center. Presence of human papilloma viral DNA was detected by in situ hybridization in formalin-fixed paraffin-embedded retinoblastoma tissues using both probes against high- and low risk HPV types. Results The mean age at diagnosis was 22.0 months (range, 1.1 to 98.0 months), and the mean age at enucleation was 27.8 months (range, 1.5 to 112.7 months) among the 54 patients with retinoblastoma. HPV was not detected in any of the retinoblastoma samples using either high risk or low risk HPV probes. Conclusions Our study, being the first study in the Korean population, proposes that HPV infection may have no causal relationship with retinoblastoma in Koreans. PMID:24082775

  12. Combined effect of fluoride and 2,3,7,8-tetrachlorodibenzo-p-dioxin on mouse dental hard tissue formation in vitro.

    Science.gov (United States)

    Salmela, Eija; Lukinmaa, Pirjo-Liisa; Partanen, Anna-Maija; Sahlberg, Carin; Alaluusua, Satu

    2011-08-01

    Fluoride interferes with enamel matrix secretion and mineralization and dentin mineralization. The most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), also impairs dental hard tissue formation and mineralization in vitro and in vivo. Our aim was to investigate in vitro whether the combined effect of sodium fluoride (NaF) and TCDD on dental hard tissue formation is potentiative. For this purpose, mandibular first and second molar tooth germs of E18 mouse embryos were cultured for 5-12 days with NaF and TCDD alone at various concentrations (2.5, 5, 10, 12.5, 15, and 20 μM and 5, 10, 12.5, and 15 nM, respectively) to determine the highest concentrations, which alone cause no or negligible effects. Morphological changes were studied from the whole tooth photographs and histological tissue sections. The concentrations found were 15 μM for NaF and 10 nM for TCDD. While at these concentrations, the effects of NaF and TCDD alone were barely detectable, the effect of simultaneous exposure on dentin and enamel formation was overt; mineralization of predentin to dentin and enamel matrix secretion and mineralization were impaired. Immunohistochemical analysis revealed that the combined exposure modified amelogenin expression by odontoblasts. Morphology of ameloblasts and the expression of amelogenin indicated that ameloblasts were still secretory. The results show that NaF and TCDD have potentiative, harmful effects on the formation of dental hard tissues. Since children can be exposed to subclinical levels of fluoride and dioxins during early childhood, coincidently with mineralization of the first permanent teeth, this finding may have clinical significance.

  13. Radioimmunoassay of cholecystokinin in human tissue and plasma

    International Nuclear Information System (INIS)

    Jansen, J.B.M.J.; Lamers, C.B.H.W.

    1983-01-01

    A highly sensitive radioimmunoassay for cholecystokinin (CCK) without any cross-reactivity with gastrin is described. The antibody was raised in a rabbit by immunisation with 30% CCK and bound to all COOH-terminal CCK-peptides containing at least 14 amino acid residues. The affinity constant of the antibody was 59.4 x 10 10 l/mol. CCK 33 conjugated to [ 125 I]hydroxyphenylpropionic acid-succinimide ester was used as label. The binding between label and antibody was inhibited by 50% (ID 50 ) at a concentration of 2.8 pmol/l cholecystokinin 33. The detection limit of the assay was between 0.5 and 1.0 pmol/l plasma. Concentrations of CCK in aqueous acid extracts of human upper small intestine were 36.5 +- 9.8 pmol/g and of human cerebral cortex 28.2 +- 2.5 pmol/g tissue. Plasma samples were extracted in 96% ethanol prior to assay. No advantage was obtained by adding aprotinin to the tubes. When frozen at -20 0 C plasma CCK was stable for at least 6 months. Basal plasma CCK concentrations in 30 normal subjects were very low, 0.9 +- 0.1 pmol/l, range 0.5 to 3.1 pmol/l. Intraduodenal administration of fat induced significant increases in plasma CCK from 1.1 +- 0.1 to 8.2 +- 1.3 pmol/l (p = 0.01). Infusion of exogenous CCK, resulting in plasma CCK levels slightly lower than those measured during administration of fat, induced pancreatic enzyme secretion and gallbladder contraction. The reliability of this radioimmunoassay for measurements of CCK in human plasma was extensively evaluated. (Auth.)

  14. Assessment of heavy metal residues in water, fish tissue and human ...

    African Journals Online (AJOL)

    MICHAEL HORSFALL

    ABSTRACT: Residual levels of lead, chromium, cadmium and zinc in water and fish tissue from. Ubeji River ... Key Words : Heavy metal residues , Fish tissue, Human blood, Ubeji River. ... is of critical concern because of their toxicity and.

  15. In vitro performance of DIAGNOdent laser fluorescence device for dental calculus detection on human tooth root surfaces

    Directory of Open Access Journals (Sweden)

    Thomas E. Rams

    2017-10-01

    Conclusions: Excellent intra- and inter-examiner reproducibility of autofluorescence intensity measurements was obtained with the DIAGNOdent laser fluorescence device on human tooth roots. Calculus-positive root surfaces exhibited significantly greater DIAGNOdent laser autofluorescence than calculus-free tooth roots, even with the laser probe tip directed parallel to root surfaces. These findings provide further in vitro validation of the potential utility of a DIAGNOdent laser fluorescence device for identifying dental calculus on human tooth root surfaces.

  16. Wear properties of dental ceramics and porcelains compared with human enamel.

    Science.gov (United States)

    D'Arcangelo, Camillo; Vanini, Lorenzo; Rondoni, Giuseppe D; De Angelis, Francesco

    2016-03-01

    Contemporary pressable and computer-aided design/manufacturing (CAD/CAM) ceramics exhibit good mechanical and esthetic properties. Their wear resistance compared with human enamel and traditional gold based alloys needs to be better investigated. The purpose of this in vitro study was to compare the 2-body wear resistance of human enamel, gold alloy, and 5 different dental ceramics, including a recently introduced zirconia-reinforced lithium silicate ceramic (Celtra Duo). Cylindrical specimens were fabricated from a Type III gold alloy (Aurocast8), 2 hot pressed ceramics (Imagine PressX, IPS e.max Press), 2 CAD/CAM ceramics (IPS e.max CAD, Celtra Duo), and a CAD/CAM feldspathic porcelain (Vitablocs Mark II) (n=10). Celtra Duo was tested both soon after grinding and after a subsequent glaze firing cycle. Ten flat human enamel specimens were used as the control group. All specimens were subjected to a 2-body wear test in a dual axis mastication simulator for 120000 loading cycles against yttria stabilized tetragonal zirconia polycrystal cusps. The wear resistance was analyzed by measuring the vertical substance loss (mm) and the volume loss (mm(3)). Antagonist wear (mm) was also recorded. Data were statistically analyzed with 1-way ANOVA tests (α=.05). The wear depth (0.223 mm) of gold alloy was the closest to that of human enamel (0.217 mm), with no significant difference (P>.05). The greatest wear was recorded on the milled Celtra Duo (wear depth=0.320 mm), which appeared significantly less wear resistant than gold alloy or human enamel (Pceramics did not statistically differ in comparison with the human enamel. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  17. 78 FR 44134 - Submission for OMB Review; 30-day Comment Request: Financial Sustainability of Human Tissue...

    Science.gov (United States)

    2013-07-23

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health Submission for OMB Review; 30-day Comment Request: Financial Sustainability of Human Tissue Biobanking (NCI) SUMMARY: Under the... Collection: Financial Sustainability of Human Tissue Biobanking, 0925-NEW, National Cancer Institute (NCI...

  18. Discarded human fetal tissue and cell cultures for transplantation research

    International Nuclear Information System (INIS)

    Hay, R.J.; Phillips, T.; Thompson, A.; Vilner, L.; Cleland, M.; Tchaw-ren Chen; Zabrenetzky, V.

    1999-01-01

    A feasibility study has been performed to explore the utility of various tissues from discarded human abortuses for transplantation and related research. Specifically, aborted fetuses plus parental blood samples and all relevant clinical data were obtained through a local hospital complex. Whenever possible, pancreas, skin and skeletal muscle, heart, liver, kidney, cartilage and lung tissues were removed, dissociated and subfractionated for cryopreservation, characterization and cultivation trials in vitro. Existing protocols for these manipulations were compared and improved upon as required. Clonal culture, cell aggregate maintenance techniques and use of feeder cell populations have been utilized where appropriate to develop quantitative comparative data. Histological and biochemical assays were applied both to evaluate separation/cultivation methods and to identify optimal culture conditions for maintaining functional cells. Immunochemical and molecular biological procedures were applied to study expression of Major Histocompatibility Vomplex (MHC) class 1 and 11 molecules on cell lines derived. Tissue and cell culture populations were examined for infections with bacteria, ftingi, mycoplasma, HIV, CMV, hepatitis B and other viruses. Only 1% of the abortuses tested were virally infected. Cytogenetic analyses confin-ned the normal diploid status in the vast majority (>98%) of lines tested. A total of over 250 abortuses have been obtained and processed. Only 25 were found to be contaminated with bacteria or fungi and unsuitable for further cultivation trials. A total of over 200 cell populations were isolated, characterized and cryopreserved for further study. Included were kidney, lung, liver and epidermal epithelia: cartilage-derived cells from the spine and epiphyses plus myogenic myoblasts. Selected lines have been immortalized using HPV I 6E6/E7 sequences. Epithelia from the liver and pancreas and cardiac myocytes were the most problematic in that initial

  19. Concentration- and time-dependent response of human gingival fibroblasts to fibroblast growth factor 2 immobilized on titanium dental implants

    Directory of Open Access Journals (Sweden)

    Ma Q

    2012-04-01

    Full Text Available Qianli Ma1*, Wei Wang1*, Paul K Chu2, Shenglin Mei1,2, Kun Ji3, Lei Jin4, Yumei Zhang11Department of Prosthetic Dentistry, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China; 2Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong, People's Republic of China; 3Department of Pediatric Dentistry, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China; 4Stomatology Department, Jinling Hospital, School of Medicine, Southern Medical University, Nanjing, People's Republic of China*These authors contributed equally to this workBackground: Titanium (Ti implants are widely used clinically, but peri-implantitis remains one of the most common and serious complications. Healthy integration between gingival tissue and the implant surface is critical to long-term success in dental implant therapy. The objective of this study was to investigate how different concentrations of immobilized fibroblast growth factor 2 (FGF2 on the titania nanotubular surface influence the response of human gingival fibroblasts (HGFs.Methods: Pure Ti metal was anodized at 20 V to form a vertically organized titanium dioxide nanotube array on which three concentrations of FGF2 (250 ng/mL, 500 ng/mL, or 1000 ng/mL were immobilized by repeated lyophilization. Surface topography was observed and FGF2 elution was detected using enzyme-linked immunosorbent assay. The bioactivity changes of dissolvable immobilized FGF2 were measured by methyl-thiazolyl-tetrazolium assay. Behavior of HGFs was evaluated using adhesion and methyl-thiazolyl-tetrazolium bromide assays.Results: The FGF2 remained for several days on the modified surface on which HGFs were cultured. Over 90% of the dissolvable immobilized FGF2 had been eluted by Day 9, whereas the FGF2 activity was found to diminish gradually from Day 1 to Day 9. The titania nanotubular surface with an optimal preparing

  20. Status quo of management of the human tissue banks in Taiwan.

    Science.gov (United States)

    Chou, Ching-Pang; Chou, Szu-Cheng; Chen, Ying-Hua; Chen, Yu-Hsuan; Lee, Ming-Shin

    2017-03-01

    As the technologies associated with transplantation and biological tissue engineering continue to advance, human cells and tissues form an integral part to the practice of regenerative medicine. The patient's use of tissues entails the risk of introducing, transmitting and spreading communicable diseases. To prevent such risk and to ensure that the human organs, tissues and cells remain intact and functional after being handled and processed, the transplanted tissues must be subject to good management standards through all stages of collection, screening, processing, storage and distribution as the safety of the users is of the utmost importance. On February 2009, the government of Taiwan promulgated the Regulations for Administration on Human Organ Bank that requires all human tissues banks to adhere to the Good Tissue Practice for Human Organ, Tissue and Cell in terms of establishment and operation in order to cope with the international management trend and the development and management need of the domestic industry. Six years have passed since the law became effective. This article seeks to introduce the current management mechanism and status quo of management of human tissue banks in Taiwan. We also conducted statistical analysis of the data relating to the tissue banks to identify potential risks and the room for improvement. The study concludes that human tissue banks in Taiwan are on the right track with their management practice, leading to a state of steady development and progress.

  1. Polybrominated diphenyl ethers: human tissue levels and toxicology.

    Science.gov (United States)

    Gill, Udai; Chu, Ih; Ryan, John J; Feeley, Mark

    2004-01-01

    with behavioral alterations in neonatal mice. When considering the outlier value for PBDE-99 at 229 ng/g, this would result in an estimated PBDE-99 body burden of 46 microg/kg, or a MOS of only 9. However, no toxicokinetics data are available for humans, and the actual margin of safety may be much smaller if based on levels in critical target organs or tissues.

  2. Technical advances in the sectioning of dental tissue and of on-section cross-linked collagen detection in mineralized teeth.

    Science.gov (United States)

    Singhrao, Sim K; Sloan, Alastair J; Smith, Emma L; Archer, Charles W

    2010-08-01

    Immunohistochemical detection of cross-linked fibrillar collagens in mineralized tissues is much desired for exploring the mechanisms of biomineralization in health and disease. Mineralized teeth are impossible to section when embedded in conventional media, thus limiting on-section characterization of matrix proteins by immunohistochemistry. We hypothesized that by using an especially formulated acrylic resin suitable for mineralized dental tissues, not only sectioning of teeth would be possible, but also our recently developed immunofluorescence labeling technique would be amenable to fully calcified tissues for characterization of dentinal fibrillar collagens, which remains elusive. The hypothesis was tested on fixed rodent teeth embedded in Technovit 9100 New. It was possible to cut thin (1 mum) sections of mineralized teeth, and immunofluorescence characterization of cross-linked type I fibrillar collagen was selected due to its abundance in dentine. Decalcified samples of teeth embedded in paraffin wax were also used to compare immunolabeling from either method using the same immunoreagents in equivalent concentrations. In the decalcified tissue sections, type I collagen labeling in the dentine along the tubules was "patchy" and the signal in the predentine was very weak. However, enhanced signal in mineralized samples with type I collagen was detected not only in the predentine but also at the limit between intertubular dentine, within the elements of the enamel organ and subgingival stroma. This report offers advances in sectioning mineralized dental tissues and allows the application of immunofluorescence not only for on-section protein detection but importantly for detecting cross-linked fibrous collagens in both soft and mineralized tissue sections.

  3. Secretion of autoimmune antibodies in the human subcutaneous adipose tissue.

    Science.gov (United States)

    Frasca, Daniela; Diaz, Alain; Romero, Maria; Thaller, Seth; Blomberg, Bonnie B

    2018-01-01

    The adipose tissue (AT) contributes to systemic and B cell intrinsic inflammation, reduced B cell responses and secretion of autoimmune antibodies. In this study we show that adipocytes in the human obese subcutaneous AT (SAT) secrete several pro-inflammatory cytokines and chemokines, which contribute to the establishment and maintenance of local and systemic inflammation, and consequent suboptimal immune responses in obese individuals, as we have previously shown. We also show that pro-inflammatory chemokines recruit immune cells expressing the corresponding receptors to the SAT, where they also contribute to local and systemic inflammation, secreting additional pro-inflammatory mediators. Moreover, we show that the SAT generates autoimmune antibodies. During the development of obesity, reduced oxygen and consequent hypoxia and cell death lead to further release of pro-inflammatory cytokines, "self" protein antigens, cell-free DNA and lipids. All these stimulate class switch and the production of autoimmune IgG antibodies which have been described to be pathogenic. In addition to hypoxia, we have measured cell cytotoxicity and DNA damage mechanisms, which may also contribute to the release of "self" antigens in the SAT. All these processes are significantly elevated in the SAT as compared to the blood. We definitively found that fat-specific IgG antibodies are secreted by B cells in the SAT and that B cells express mRNA for the transcription factor T-bet and the membrane marker CD11c, both involved in the production of autoimmune IgG antibodies. Finally, the SAT also expresses RNA for cytokines known to promote Germinal Center formation, isotype class switch, and plasma cell differentiation. Our results show novel mechanisms for the generation of autoimmune antibody responses in the human SAT and allow the identification of new pathways to possibly manipulate in order to reduce systemic inflammation and autoantibody production in obese individuals.

  4. Nattokinase-promoted tissue plasminogen activator release from human cells.

    Science.gov (United States)

    Yatagai, Chieko; Maruyama, Masugi; Kawahara, Tomoko; Sumi, Hiroyuki

    2008-01-01

    When heated to a temperature of 70 degrees C or higher, the strong fibrinolytic activity of nattokinase in a solution was deactivated. Similar results were observed in the case of using Suc-Ala-Ala-Pro-Phe-pNA and H-D-Val-Leu-Lys-pNA, which are synthetic substrates of nattokinase. In the current study, tests were conducted on the indirect fibrinolytic effects of the substances containing nattokinase that had been deactivated through heating at 121 degrees C for 15 min. Bacillus subtilis natto culture solutions made from three types of bacteria strain were heat-treated and deactivated, and it was found that these culture solutions had the ability to generate tissue plasminogen activators (tPA) from vascular endothelial cells and HeLa cells at certain concentration levels. For example, it was found that the addition of heat-treated culture solution of the Naruse strain (undiluted solution) raises the tPA activity of HeLa cells to about 20 times that of the control. Under the same conditions, tPA activity was raised to a level about 5 times higher for human vascular endothelial cells (HUVEC), and to a level about 24 times higher for nattokinase sold on the market. No change in cell count was observed for HeLa cells and HUVEC in the culture solution at these concentrations, and the level of activity was found to vary with concentration. Copyright 2009 S. Karger AG, Basel.

  5. Mercury content in amalgam tattoos of human oral mucosa and its relation to local tissue reactions

    Energy Technology Data Exchange (ETDEWEB)

    Forsell, M.; Larsson, B.; Ljungqvist, A.; Carlmark, B.; Johansson, O

    1998-02-01

    Mucosal biopsies from 48 patients with and 9 without amalgam tattoos were analysed with respect to their mercury content, distribution of mercury in the tissue, and histological tissue reactions. The distribution of mercury was assessed by auto-metallography (AMG), a silver amplification technique. The mercury content was determined by energy dispersive X-ray fluorescence (EDXRF), a multielemental analysis. Mercury was observed in connective tissue where it was confined to fibroblasts and macrophages, in vessel walls and in structures with the histological character of nerve fibres. A correlation was found between the histopathological tissue reaction, the type of mercury deposition, the intensity of the AMG reaction, and the mercury content. Mercury was also found in patients with amalgam dental fittings but without amalgam tattoos. (au) 24 refs.

  6. Mercury content in amalgam tattoos of human oral mucosa and its relation to local tissue reactions

    International Nuclear Information System (INIS)

    Forsell, M.; Larsson, B.; Ljungqvist, A.; Carlmark, B.; Johansson, O.

    1998-01-01

    Mucosal biopsies from 48 patients with and 9 without amalgam tattoos were analysed with respect to their mercury content, distribution of mercury in the tissue, and histological tissue reactions. The distribution of mercury was assessed by auto-metallography (AMG), a silver amplification technique. The mercury content was determined by energy dispersive X-ray fluorescence (EDXRF), a multielemental analysis. Mercury was observed in connective tissue where it was confined to fibroblasts and macrophages, in vessel walls and in structures with the histological character of nerve fibres. A correlation was found between the histopathological tissue reaction, the type of mercury deposition, the intensity of the AMG reaction, and the mercury content. Mercury was also found in patients with amalgam dental fittings but without amalgam tattoos. (au)

  7. Mucopolysaccharidosis enzyme production by bone marrow and dental pulp derived human mesenchymal stem cells.

    Science.gov (United States)

    Jackson, Matilda; Derrick Roberts, Ainslie; Martin, Ellenore; Rout-Pitt, Nathan; Gronthos, Stan; Byers, Sharon

    2015-04-01

    Mucopolysaccharidoses (MPS) are inherited metabolic disorders that arise from a complete loss or a reduction in one of eleven specific lysosomal enzymes. MPS children display pathology in multiple cell types leading to tissue and organ failure and early death. Mesenchymal stem cells (MSCs) give rise to many of the cell types affected in MPS, including those that are refractory to current treatment protocols such as hematopoietic stem cell (HSC) based therapy. In this study we compared multiple MPS enzyme production by bone marrow derived (hBM) and dental pulp derived (hDP) MSCs to enzyme production by HSCs. hBM MSCs produce significantly higher levels of MPS I, II, IIIA, IVA, VI and VII enzyme than HSCs, while hDP MSCs produce significantly higher levels of MPS I, IIIA, IVA, VI and VII enzymes. Higher transfection efficiency was observed in MSCs (89%) compared to HSCs (23%) using a lentiviral vector. Over-expression of four different lysosomal enzymes resulted in up to 9303-fold and up to 5559-fold greater levels in MSC cell layer and media respectively. Stable, persistent transduction of MSCs and sustained over-expression of MPS VII enzyme was observed in vitro. Transduction of MSCs did not affect the ability of the cells to differentiate down osteogenic, adipogenic or chondrogenic lineages, but did partially delay differentiation down the non-mesodermal neurogenic lineage. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Interleukin 1-beta analysis in chronically inflamed and healthy human dental pulp

    Directory of Open Access Journals (Sweden)

    Šubarić Ljiljana

    2017-01-01

    Full Text Available Background/Aim. Proinflammatory cytokines can act like endogenous pyrogen interleukin 1 (IL-1, interleukin 6 (IL-6 and tumour necrosis factor alpha (TNF α which regulate the synthesis of secondary mediators and other proinflammatory cytokines through macrophages and mesenchymal cells. They stimulate acute-phase proteins and attract inflammatory cells. The aim of this study was to determine interleukin 1-β (IL-1 β concentrations in chronically inflamed and healthy dental pulps. Methods. A total of 41 pulps (19 from patients with pulpitis chronic causa and 22 from patients with pulpatis chronic aperta, divided into two groups, were obtained from teeth with chronic pulp inflammation. The control group consisted of 12 teeth with healthy pulp. After extirpation, pulp samples were immediately placed in sterile Eppendorf tubes and frozen. After that, homogenisation was performed by a Teflon® pestle in ice-cold phosphate buffer solution at pH 7.4 whose volume was adjusted according to the weight of tissue. The supernatant was then frozen at -70°C until the performance of appropriate biochemical analyses. Cytokine IL-1 β value was determined by a commercial enzyme- linked immunosorbent assay (ELISA test. We applied the high sensitivity system technique, which may register low levels of cytokines, ranging from 0.125 to 8.0 pg/mL for IL-1 β. Results. By comparing the mean value of IL-1β, in the pulps we can see a statistically significant difference (p < 0.01 among them. The highest value of IL-1 β was in the subjects with pulpitis chronica clausa and it was 6.21 ± 2.70 pg/mL. Conclusion. Proinflammatory cytokine IL-1 β is present in detectable quantities in the pulp tissue of all vital pulps. Its highest concentrations were found in the sample group with pulpitis chronica clausa.

  9. Characterization of RNA isolated from eighteen different human tissues: results from a rapid human autopsy program.

    Science.gov (United States)

    Walker, Douglas G; Whetzel, Alexis M; Serrano, Geidy; Sue, Lucia I; Lue, Lih-Fen; Beach, Thomas G

    2016-09-01

    Many factors affect the integrity of messenger RNA from human autopsy tissues including postmortem interval (PMI) between death and tissue preservation and the pre-mortem agonal and disease states. In this communication, we describe RNA isolation and characterization of 389 samples from 18 different tissues from elderly donors who were participants in a rapid whole-body autopsy program located in Sun City, Arizona ( www.brainandbodydonationprogram.org ). Most tissues were collected within a PMI of 2-6 h (median 3.15 h; N = 455), but for this study, tissue from cases with longer PMIs (1.25-29.25 h) were included. RNA quality was assessed by RNA integrity number (RIN) and total yield (ng RNA/mg tissue). RIN correlated with PMI for heart (r = -0.531, p = 0.009) and liver (r = -558, p = 0.0017), while RNA yield correlated with PMI for colon (r = -485, p = 0.016) and skin (r = -0.460, p = 0.031). RNAs with the lowest integrity were from skin and cervix where 22.7 and 31.4 % of samples respectively failed to produce intact RNA; by contrast all samples from esophagus, lymph node, jejunum, lung, stomach, submandibular gland and kidney produced RNA with measurable RINs. Expression levels in heart RNA of 4 common housekeeping normalization genes showed significant correlations of Ct values with RIN, but only one gene, glyceraldehyde-3 phosphate dehydrogenase, showed a correlation of Ct with PMI. There were no correlations between RIN values obtained for liver, adrenal, cervix, esophagus and lymph node and those obtained from corresponding brain samples. We show that high quality RNA can be produced from most human autopsy tissues, though with significant differences between tissues and donors. The RNA stability and yield did not depend solely on PMI; other undetermined factors are involved, but these do not include the age of the donor.

  10. Dental caries

    DEFF Research Database (Denmark)

    Pitts, Nigel B; Zero, Domenick T; Marsh, Phil D

    2017-01-01

    Dental caries is a biofilm-mediated, sugar-driven, multifactorial, dynamic disease that results in the phasic demineralization and remineralization of dental hard tissues. Caries can occur throughout life, both in primary and permanent dentitions, and can damage the tooth crown and, in later life......, exposed root surfaces. The balance between pathological and protective factors influences the initiation and progression of caries. This interplay between factors underpins the classification of individuals and groups into caries risk categories, allowing an increasingly tailored approach to care. Dental...... caries is an unevenly distributed, preventable disease with considerable economic and quality-of-life burdens. The daily use of fluoride toothpaste is seen as the main reason for the overall decline of caries worldwide over recent decades. This Primer aims to provide a global overview of caries...

  11. Dental Amalgam

    Science.gov (United States)

    ... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

  12. Human Dental Pulp Stem Cells via the NF-κB Pathway

    Directory of Open Access Journals (Sweden)

    Shensheng Gu

    2015-07-01

    Full Text Available Background/Aims: Odontogenic differentiation of human dental pulp stem cells (HDPSCs is regulated by multiple factors and signaling molecules. However, their regulatory mechanisms are not completely understood. In this study, we investigated the role of Zinc finger and BTB domain-containing 20 (ZBTB20 in odontoblastic differentiation of HDPSCs. Methods: HDPSCs were obtained from human third molars and ZBTB20 expression was examined by qRT-PCR and western blot. Their osteo/odontogenic differentiation and the involvement of NF-κB pathway were subsequently investigated. Results: The expression of ZBTB20 is upregulated in a time-dependent manner during odontogenic differentiation of hDPSCs. Inhibition of ZBTB20 reduced osteogenic medium (OM-induced odontogenic differentiation, reflected in decreased alkaline phosphatase (ALP activity, mineralized nodule formation and mRNA expression of odonto/osteogenic marker genes. In contrast, overexpression of ZBTB20 enhanced ALP activity, mineralization and the expression of differentiation marker genes. Furthermore, the expression of IκBa was increased by ZBTB20 silencing in HDPSCs, whereas ZBTB20 overexpression decreased IκBa and enhanced nuclear NF-κB p65. Inhibition of the NF-κB pathway significantly suppressed the odontogenic differentiation of HDPSCs induced by ZBTB20. Conclusion: This study shows for the first time that ZBTB20 plays an important role during odontoblastic differentiation of HDPSCs and may have clinical implications for regenerative endodontics.

  13. Histological evaluations and inflammatory responses of different dental implant abutment materials: A human histology pilot study.

    Science.gov (United States)

    Sampatanukul, Teeratida; Serichetaphongse, Pravej; Pimkhaokham, Atiphan

    2018-04-01

    Improvements of soft tissue to the abutment surface results in more stable peri-implant conditions, however, few human histological studies have compared soft tissue responses around different abutment materials. To describe the peri-implant tissue around 3 abutment materials; titanium, zirconia, and gold alloy, over an 8-week healing period. Fifteen edentulous sites were treated with implants. Eight weeks later, peri-implant tissue was harvested and processed using a nonseparation resin embedded technique. The tissue attachment characteristics were assessed at clinical stages using the gingival index (GI) score, surgical stage (surgical score), and histological stage (histological attachment percentage). Additionally, the inflammatory responses were evaluated using inflammatory extent and inflammatory cellularity grades. Nonparametrical statistics were used to describe the GI and surgical scores, and analytical statistics were used to analyze the histological attachment percentages as well as the inflammatory extent and cellularity grades amongst the 3 groups. There were no statistically significant differences among the groups for GI score (P = .071) and surgical score (P = .262). Titanium and zirconia exhibited nearly similar mean histological attachment percentages while gold alloy had a significantly lower percentage (P = .004). For the inflammatory extent and cellularity grades, the odds of being one grade higher for gold alloy abutment was 5.18 and 17.8 times that of titanium abutment, respectively. However, for the zirconia abutment, the odds were 0.87 and 7.5 times higher than the titanium group. The tissue around the gold alloy abutments resulted in worse attachment conditions compared with the titanium and zirconia abutments. Inflammation tended to be higher in the tissue around the gold alloy abutments than the titanium and zirconia abutments. © 2017 Wiley Periodicals, Inc.

  14. Terahertz pulsed imaging of freshly excised human colonic tissues

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Caroline B; Gibson, Adam P [Department of Medical Physics and Bioengineering, University College London, London, WC1E 6BT (United Kingdom); Fitzgerald, Anthony; Wallace, Vincent P [School of Physics, University of Western Australia, Crawley 6009 (Australia); Reese, George; Tekkis, Paris [Division of Surgery, Chelsea and Westminster Campus, Imperial College London, London (United Kingdom); Goldin, Robert [Centre for Pathology, Imperial College London, St Mary' s Campus, London (United Kingdom); O' Kelly, P S [TeraView Ltd, Platinum Building, St John' s Innovation Park, Cowley Road, Cambridge, CB4 0WS (United Kingdom); Pickwell-MacPherson, Emma, E-mail: c.reid@medphys.ucl.ac.uk [Department of Electronic Engineering, Chinese University of Hong Kong, Shatin, NT (Hong Kong)

    2011-07-21

    We present the results from a feasibility study which measures properties in the terahertz frequency range of excised cancerous, dysplastic and healthy colonic tissues from 30 patients. We compare their absorption and refractive index spectra to identify trends which may enable different tissue types to be distinguished. In addition, we present statistical models based on variations between up to 17 parameters calculated from the reflected time and frequency domain signals of all the measured tissues. These models produce a sensitivity of 82% and a specificity of 77% in distinguishing between healthy and all diseased tissues and a sensitivity of 89% and a specificity of 71% in distinguishing between dysplastic and healthy tissues. The contrast between the tissue types was supported by histological staining studies which showed an increased vascularity in regions of increased terahertz absorption.

  15. Terahertz pulsed imaging of freshly excised human colonic tissues

    International Nuclear Information System (INIS)

    Reid, Caroline B; Gibson, Adam P; Fitzgerald, Anthony; Wallace, Vincent P; Reese, George; Tekkis, Paris; Goldin, Robert; O'Kelly, P S; Pickwell-MacPherson, Emma

    2011-01-01

    We present the results from a feasibility study which measures properties in the terahertz frequency range of excised cancerous, dysplastic and healthy colonic tissues from 30 patients. We compare their absorption and refractive index spectra to identify trends which may enable different tissue types to be distinguished. In addition, we present statistical models based on variations between up to 17 parameters calculated from the reflected time and frequency domain signals of all the measured tissues. These models produce a sensitivity of 82% and a specificity of 77% in distinguishing between healthy and all diseased tissues and a sensitivity of 89% and a specificity of 71% in distinguishing between dysplastic and healthy tissues. The contrast between the tissue types was supported by histological staining studies which showed an increased vascularity in regions of increased terahertz absorption.

  16. Development of a Novel Large Animal Model to Evaluate Human Dental Pulp Stem Cells for Articular Cartilage Treatment.

    Science.gov (United States)

    Fernandes, Tiago Lazzaretti; Shimomura, Kazunori; Asperti, Andre; Pinheiro, Carla Cristina Gomes; Caetano, Heloísa Vasconcellos Amaral; Oliveira, Claudia Regina G C M; Nakamura, Norimasa; Hernandez, Arnaldo José; Bueno, Daniela Franco

    2018-05-04

    Chondral lesion is a pathology with high prevalence, reaching as much as 63% of general population and 36% among athletes. The ability of human Dental Pulp Stem Cells (DPSCs) to differentiate into chondroblasts in vitro suggests that this stem cell type may be useful for tissue bioengineering. However, we have yet to identify a study of large animal models in which DPSCs were used to repair articular cartilage. Therefore, this study aimed to describe a novel treatment for cartilage lesion with DPSCs on a large animal model. Mesenchymal stem cells (MSC) were obtained from deciduous teeth and characterized by flow cytometry. DPSCs were cultured and added to a collagen ty