scholarly journals Surface Pre-Reacted Glass Filler Contributes to Tertiary Dentin Formation through a Mechanism Different Than That of Hydraulic Calcium-Silicate Cement

2019 ◽  
Vol 8 (9) ◽  
pp. 1440 ◽  
Author(s):  
Motoki Okamoto ◽  
Manahil Ali ◽  
Shungo Komichi ◽  
Masakatsu Watanabe ◽  
Hailing Huang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Calcium Silicate ◽  
Dental Pulp ◽  
Healing Process ◽  
Calcium Silicate Cement ◽  
Tertiary Dentin ◽  
Regulated Gene Expression ◽  
Dentin Formation ◽  
Hydraulic Calcium Silicate Cement

The induction of tissue mineralization and the mechanism by which surface pre-reacted glass-ionomer (S-PRG) cement influences pulpal healing remain unclear. We evaluated S-PRG cement-induced tertiary dentin formation in vivo, and its effect on the pulp cell healing process in vitro. Induced tertiary dentin formation was evaluated with micro-computed tomography (μCT) and scanning electron microscopy (SEM). The distribution of elements from the S-PRG cement in pulpal tissue was confirmed by micro-X-ray fluorescence (μXRF). The effects of S-PRG cement on cytotoxicity, proliferation, formation of mineralized nodules, and gene expression in human dental pulp stem cells (hDPSCs) were assessed in vitro. μCT and SEM revealed that S-PRG induced tertiary dentin formation with similar characteristics to that induced by hydraulic calcium-silicate cement (ProRoot mineral trioxide aggregate (MTA)). μXRF showed Sr and Si ion transfer into pulpal tissue from S-PRG cement. Notably, S-PRG cement and MTA showed similar biocompatibility. A co-culture of hDPSCs and S-PRG discs promoted mineralized nodule formation on surrounding cells. Additionally, S-PRG cement regulated the expression of genes related to osteo/dentinogenic differentiation. MTA and S-PRG regulated gene expression in hDPSCs, but the patterns of regulation differed. S-PRG cement upregulated CXCL-12 and TGF-β1 gene expression. These findings showed that S-PRG and MTA exhibit similar effects on dental pulp through different mechanisms.

Effect of a Calcium-silicate-based Restorative Cement on Pulp Repair

2012 ◽  
Vol 91 (12) ◽  
pp. 1166-1171 ◽  
Author(s):  
X.V. Tran ◽  
C. Gorin ◽  
C. Willig ◽  
B. Baroukh ◽  
B. Pellat ◽  
...  
Keyword(s):  
Calcium Silicate ◽  
Glass Ionomer Cement ◽  
Repair Process ◽  
Male Rats ◽  
Time Points ◽  
Tertiary Dentin ◽  
Pulp Exposure ◽  
Calcium Silicate Cements ◽  
Reparative Process ◽  
Dentin Formation

In cases of pulp injury, capping materials are used to enhance tertiary dentin formation; Ca(OH)2 and MTA are the current gold standards. The aim of this study was to evaluate the capacity of a new calcium-silicate-based restorative cement to induce pulp healing in a rat pulp injury model. For that purpose, cavities with mechanical pulp exposure were prepared on maxillary first molars of 27 six-week-old male rats, and damaged pulps were capped with either the new calcium-silicate-based restorative cement (Biodentine), MTA, or Ca(OH)2. Cavities were sealed with glass-ionomer cement, and the repair process was assessed at several time-points. At day 7, our results showed that both the evaluated cement and MTA induced cell proliferation and formation of mineralization foci, which were strongly positive for osteopontin. At longer time-points, we observed the formation of a homogeneous dentin bridge at the injury site, secreted by cells displaying an odontoblastic phenotype. In contrast, the reparative tissue induced by Ca(OH)2 showed porous organization, suggesting a reparative process different from those induced by calcium silicate cements. Analysis of these data suggests that the evaluated cement can be used for direct pulp-capping.

scholarly journals Lithium Chloride Exerts Differential Effects on Dentinogenesis and Osteogenesis in Primary Pulp Cultures

2021 ◽  
Vol 2 ◽  
Author(s):  
Anushree Vijaykumar ◽  
Mina Mina
Keyword(s):  
Dental Pulp ◽  
Osteoblast Differentiation ◽  
Prolonged Treatment ◽  
Odontoblast Differentiation ◽  
Positive Effects ◽  
Reparative Dentin ◽  
Dentin Formation ◽  
Reparative Dentin Formation

Wnt/β-catenin signaling is known to play essential roles in odontoblast differentiation and reparative dentin formation. Various Wnt activators including LiCl have been increasingly studied for their effectiveness to induce repair of the dentin-pulp complex. LiCl is a simple salt thought to activate Wnt/β-catenin signaling by inhibiting GSK3β. Previous in vitro and in vivo studies showed that LiCl increased odontoblast differentiation and enhanced reparative dentin formation. However, the underlying molecular and cellular mechanisms by which LiCl regulates odontoblast and osteoblast differentiation during reparative dentinogenesis are not well-understood. Our in vitro studies show that exposure of early dental pulp progenitors to LiCl increased the survival and the pool of αSMA+ progenitors, leading to enhanced odontoblast and osteoblast differentiation. The positive effects of LiCl in the differentiation of osteoblasts and odontoblasts from αSMA+ progenitors are mediated by Wnt/β-catenin signaling. Our results also showed that continuous and late exposure of dental pulp cells to LiCl increased the expression of odontoblast markers through Wnt/β-catenin signaling, and the number of odontoblasts expressing DMP1-Cherry and DSPP-Cerulean transgenes. However, unlike the early treatment, both continuous and late treatments decreased the expression of Bsp and the expression of BSP-GFPtpz transgene. These observations suggest that prolonged treatment with LiCl in more mature cells of the dental pulp has an inhibitory effect on osteoblast differentiation. The inhibitory effects of LiCl on osteogenesis and Bsp were not mediated through Wnt/β-catenin signaling. These observations suggest that the effects of LiCl, and GSK3β antagonists on reparative dentinogenesis involve multiple pathways and are not specific to Wnt/β-catenin signaling.

scholarly journals Quantitative Evaluation by Glucose Diffusion of Microleakage in Aged Calcium Silicate-Based Open-Sandwich Restorations

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
S. Koubi ◽  
H. Elmerini ◽  
G. Koubi ◽  
H. Tassery ◽  
J. Camps
Keyword(s):  
Calcium Silicate ◽  
Glass Ionomer Cement ◽  
Glass Ionomer ◽  
Calcium Silicate Cement ◽  
Resin Modified Glass Ionomer ◽  
Glucose Diffusion ◽  
Negative Controls ◽  
Phosphate Buffered Saline ◽  
Ionomer Cement

This study compared thein vitromarginal integrity of open-sandwich restorations based on aged calcium silicate cement versus resin-modified glass ionomer cement. Class II cavities were prepared on 30 extracted human third molars. These teeth were randomly assigned to two groups () to compare a new hydraulic calcium silicate cement designed for restorative dentistry (Biodentine, Septodont, Saint Maur des Fossés, France) with a resin-modified glass ionomer cement (Ionolux, Voco, Cuxhaven, Germany) in open-sandwich restorations covered with a light-cured composite. Positive () and negative () controls were included. The teeth simultaneously underwent thermocycling and mechanocycling using a fatigue cycling machine (1,440 cycles, 5–55°C; 86,400 cycles, 50 N/cm2). The specimens were then stored in phosphate-buffered saline to simulate aging. After 1 year, the teeth were submitted to glucose diffusion, and the resulting data were analyzed with a nonparametric Mann-Whitney test. The Biodentine group and the Ionolux group presented glucose concentrations of 0.074 ± 0.035 g/L and 0.080 ± 0.032 g/L, respectively. No statistically significant differences were detected between the two groups. Therefore, the calcium silicate-based material performs as well as the resin-modified glass ionomer cement in open-sandwich restorations.

In vitro and in vivo osteogenesis of gelatin-modified calcium silicate cement with washout resistance

2020 ◽  
Vol 117 ◽  
pp. 111297 ◽  
Author(s):  
I-Ting Wu ◽  
Pan-Fu Kao ◽  
Yun-Ru Huang ◽  
Shinn-Jyh Ding
Keyword(s):  
Calcium Silicate ◽  
Calcium Silicate Cement

In Vitro MR Imaging of Regulated Gene Expression

Radiology ◽  
2003 ◽  
Vol 228 (2) ◽  
pp. 488-492 ◽  
Author(s):  
Heiko Alfke ◽  
Hubert Stöppler ◽  
Frank Nocken ◽  
Johannes T. Heverhagen ◽  
Beate Kleb ◽  
...  
Keyword(s):  
Gene Expression ◽  
Mr Imaging ◽  
Regulated Gene Expression

scholarly journals An Improved Method for the Study of Apoptosis-Related Genes Using the Tet-On System

2011 ◽  
Vol 16 (3) ◽  
pp. 332-337 ◽  
Author(s):  
Marc W. Halterman
Keyword(s):  
Gene Expression ◽  
Caspase 3 ◽  
Functional Characterization ◽  
Continuous Exposure ◽  
Genetic Screens ◽  
Pulse Dose ◽  
Target Effect ◽  
Regulated Gene Expression

Inducible gene expression systems are particularly useful for the functional characterization of genes with putative toxic properties. In the course of studying the role of hypoxia-regulated gene expression on cell survival using the tetracycline-inducible (tet-on) system, the author noted that exposure to the inducing ligand doxycycline (dox) inhibited caspase-3 cleavage in control samples. To limit this confounding off-target effect, he devised an in vitro pulse dose, delayed-injury protocol testing both dox and a novel tetracycline analog 9-t-butyl doxycycline (9-TB). Although 9-TB induced higher transgene levels compared to matched concentrations of dox, continuous exposure to both drugs inhibited caspase-3 cleavage in hypoxic samples. Conversely, a 6-h pulse dose of 9-TB followed by a 40-h washout period prior to hypoxic challenge activated robust transgene expression and lessened the inhibitory effects on caspase-3 processing. It is anticipated that these protocol modifications will improve the performance of tet-regulated genetic screens, particularly in situations where cell death is used as a primary end point.

scholarly journals Drought Stress Enhances Up-Regulation of Anthocyanin Biosynthesis in Grapevine leafroll-associated virus 3-Infected in vitro Grapevine (Vitis vinifera) Leaves

Plant Disease ◽  
2017 ◽  
Vol 101 (9) ◽  
pp. 1606-1615 ◽  
Author(s):  
Zhen-Hua Cui ◽  
Wen-Lu Bi ◽  
Xin-Yi Hao ◽  
Peng-Min Li ◽  
Ying Duan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Drought Stress ◽  
Vitis Vinifera ◽  
Anthocyanin Biosynthesis ◽  
Anthocyanin Accumulation ◽  
Expression Levels ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Regulated Gene Expression

Reddish-purple coloration on the leaf blades and downward rolling of leaf margins are typical symptoms of grapevine leafroll disease (GLD) in red-fruited grapevine cultivars. These typical symptoms are attributed to the expression of genes encoding enzymes for anthocyanins synthesis, and the accumulation of flavonoids in diseased leaves. Drought has been proven to accelerate development of GLD symptoms in virus-infected leaves of grapevine. However, it is not known how drought affects GLD expression nor how anthocyanin biosynthesis in virus-infected leaves is altered. The present study used HPLC to determine the types and levels of anthocyanins, and applied reverse transcription quantitative polymerase chain reaction (RT-qPCR) to analyze the expression of genes encoding enzymes for anthocyanin synthesis. Plantlets of Grapevine leafroll-associated virus 3 (GLRaV-3)-infected Vitis vinifera ‘Cabernet Sauvignon’ were grown in vitro under PEG-induced drought stress. HPLC found no anthocyanin-related peaks in the healthy plantlets with or without PEG-induced stress, while 11 peaks were detected in the infected plantlets with or without PEG-induced drought stress, but the peaks were significantly higher in infected drought-stressed plantlets. Increased accumulation of total anthocyanin compounds was related to the development of GLD symptoms in the infected plantlets under PEG stress. The highest level of up-regulated gene expression was found in GLRaV-3-infected leaves with PEG-induced drought stress. Analyses of variance and correlation of anthocyanin accumulation with related gene expression levels found that GLRaV-3-infection was the key factor in increased anthocyanin accumulation. This accumulation involved the up-regulation of two key genes, MYBA1 and UFGT, and their expression levels were further enhanced by drought stress.

scholarly journals 238.Determination of differentially displayed oxygen-sensitive genes in bovine blastocysts

2004 ◽  
Vol 16 (9) ◽  
pp. 238
Author(s):  
A. J. Harvey ◽  
M. Kirstein ◽  
A. Navarrete-Santos ◽  
K. L. Kind ◽  
B. Fischer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Differential Display ◽  
Target Genes ◽  
Hypoxia Inducible Factor ◽  
Developmental Competence ◽  
Myelogenous Leukemia ◽  
Bovine Embryo ◽  
Nadh Dehydrogenase Subunit 2 ◽  
Regulated Gene Expression

Oxygen-regulated gene expression in the bovine embryo contrasts markedly with that observed in the mouse. Under low (2%) oxygen moderate changes in gene expression are observed in the bovine blastocyst, compared with 3- to 4-fold increases in the mouse. We have determined that these moderate gene expression changes are most likely regulated by Hypoxia-Inducible Factor (HIF)-2 transcription factor activity in the bovine, in the absence of HIF1, although HIF2 target genes are largely unknown. The aim of this study was to screen, by differential display RT-PCR, for putative oxygen-regulated transcripts that might confer developmental competence in blastocysts cultured under varying oxygen atmospheres post compaction. In vitro-produced bovine blastocysts were generated using standard protocols. Compact morulae were randomly allocated to treatments under either 2%, 7% or 20% oxygen for 72 h from Day 5. Blastocyst RNA was isolated using TriReagent and samples were reverse transcribed using Superscript II. cDNA was amplified using 10-mer primers in reactions containing 32Pα-labelled dCTP. Resulting bands were detected by autoradiography, excised, purified and ligated into pGEMT vectors for transformation and sequencing. Seven clones were identified as having high homology with known sequences in GenBank. Real-time PCR was undertaken to confirm oxygen-regulation using Sybr green master mix. Myotrophin mRNA was significantly increased following 2% oxygen culture, compared with 20% cultured blastocysts (P�<�0.01), as was GLUT1 (P�<�0.01). The expression of anaphase-promoting complex showed a significant association with oxygen, being higher in 2% cultured blastocysts (P�<�0.05). Acetyl-coA-acetyltransferase I, chronic myelogenous leukemia tumor antigen (CML66), cyclin I, NADH dehydrogenase subunit 2 and ribonucleotide reductase M1, genes identified using differential display, were not altered by post compaction oxygen concentration. This study has identified potentially HIF2-specific regulated genes, and supports the hypothesis that reduced oxygen concentrations post-compaction may influence bovine embryo development through oxygen-regulated changes in gene expression.

Templated dentin formation by dental pulp stem cells on banded collagen bundles nucleated on electrospun poly (4-vinyl pyridine) fibers in vitro

2018 ◽  
Vol 76 ◽  
pp. 80-88 ◽  
Author(s):  
Linxi Zhang ◽  
Yingjie Yu ◽  
Kuan-che Feng ◽  
Ya-chen Chuang ◽  
Xianghao Zuo ◽  
...  
Keyword(s):  
Stem Cells ◽  
Dental Pulp ◽  
Dental Pulp Stem Cells ◽  
Vinyl Pyridine ◽  
Dentin Formation
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