Nanoscale Characterisation of Salivary Pellicle

MRS Proceedings ◽

10.1557/proc-841-r2.3/y2.3 ◽

2004 ◽

Vol 841 ◽

Cited By ~ 1

Author(s):

Michelle E. Dickinson ◽

Adrian B. Mann

Keyword(s):

Dental Enamel ◽

Tooth Surface ◽

Surface Adhesion ◽

Human Enamel ◽

Oral Physiology ◽

Salivary Pellicle ◽

Initial Adsorption ◽

Dietary Agents

ABSTRACTSalivary pellicle is an organic biofilm formed by the physisorption of proteins and carbohydrates onto the surface of dental enamel exposed to the oral environment. The pellicle has several key roles in oral physiology including lubrication and reduction of friction between teeth during mastication, as well as chemical protection of the enamel against acidic solutions. However, pellicle proteins are known to react with dietary compounds to cause extrinsic staining on the tooth surface.In this study, nanoindentation and AFM have been used in vitro to examine the acquired salivary pellicle formed in vivo on dental enamel. The mechanical properties, growth, structure and morphology of pellicle grown in vivo on human enamel surfaces have been analysed. In addition, the effects of dietary agents such as polyphenols on the pellicle's morphology and properties have been studied.It was found that initial adsorption of proteins on the enamel surface occurred within 30 seconds of exposure to the oral cavity, with full growth achieved within 2 hours. Differences in the properties of the pellicles such as surface adhesion, and time dependent effects due to polyphenol interaction were measured using nanoindentation. It was seen that the polyphenol interaction has a significant effect on these properties. These results suggest that the stained pellicle is mechanically stiffer, but also less viscous and more fluid like. This could explain why traditional tooth brushing techniques do not efficiently remove this layer.

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Nanoscale Characterisation of Salivary Pellicle

MRS Proceedings ◽

10.1557/proc-844-y2.3/r2.3 ◽

2004 ◽

Vol 844 ◽

Cited By ~ 2

Author(s):

Michelle E. Dickinso ◽

Adrian B. Mann

Keyword(s):

Dental Enamel ◽

Tooth Surface ◽

Surface Adhesion ◽

Human Enamel ◽

Oral Physiology ◽

Salivary Pellicle ◽

Initial Adsorption ◽

Dietary Agents

AbstractSalivary pellicle is an organic biofilm formed by the physisorption of proteins and carbohydrates onto the surface of dental enamel exposed to the oral environment. The pellicle has several key roles in oral physiology including lubrication and reduction of friction between teeth during mastication, as well as chemical protection of the enamel against acidic solutions. However, pellicle proteins are known to react with dietary compounds to cause extrinsic staining on the tooth surface.In this study, nanoindentation and AFM have been used in vitro to examine the acquired salivary pellicle formed in vivo on dental enamel. The mechanical properties, growth, structure and morphology of pellicle grown in vivo on human enamel surfaces have been analysed. In addition, the effects of dietary agents such as polyphenols on the pellicle's morphology and properties have been studied.It was found that initial adsorption of proteins on the enamel surface occurred within 30 seconds of exposure to the oral cavity, with full growth achieved within 2 hours. Differences in the properties of the pellicles such as surface adhesion, and time dependent effects due to polyphenol interaction were measured using nanoindentation. It was seen that the polyphenol interaction has a significant effect on these properties. These results suggest that the stained pellicle is mechanically stiffer, but also less viscous and more fluid like. This could explain why traditional tooth brushing techniques do not efficiently remove this layer.

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Polydimethylsiloxane as a Tooth Surface-Bound Carrier of Triclosan: a New Concept in Chemical Plaque Inhibition

Advances in Dental Research ◽

10.1177/08959374940080022101 ◽

1994 ◽

Vol 8 (2) ◽

pp. 272-277 ◽

Cited By ~ 7

Author(s):

G. Rølla ◽

J.E. Ellingsen ◽

D. Gaare

Keyword(s):

Silicone Oil ◽

Dental Enamel ◽

Solid Surfaces ◽

Tooth Surface ◽

Water Repellent ◽

Streptococcus Sobrinus ◽

Gingival Health ◽

Low Solubility

Polydimethylsiloxane (silicone oil) has an extremely low surface tension: It spreads over solid surfaces and forms a tenacious film which is hydrophobic and water-repellent. It is known that this liquid binds to hydroxyapatite and to dental enamel and changes the properties of these solids. It has been suggested that silicone oil may be applied to teeth and serve as a reservoir of lipid-soluble antibacterial substances which presumably will be slowly released into saliva due to their low solubility in water. The present paper reviews recent papers where this hypothesis is tested in vitro and in vivo. It was first shown that test tubes treated with the combination silicone oil and the lipid-soluble agent triclosan acquired a layer which inhibited bacterial growth in a culture of Streptococcus sobrinus (OMZ 176) which was grown in sucrose. Both growth in the medium and polysaccharide adsorption to the glass wall were inhibited. Silicone oil alone inhibited polysaccharide adsorption to some degree, whereas the growth in the medium was not affected. In a similar clinical plaque-inhibition study, topical application of silicone oil/triclosan to the teeth of a test panel showed marked plaque inhibition, particularly giving an increased number of teeth with scores of 0 (no plaque). In a study where silicone oil and triclosan were incorporated into a toothpaste, improved gingival health was observed after a period of one month. It is concluded that the use of silicone oil/ triclosan in the manner described above represents a new principle in preventive dentistry. The results obtained seem to warrant further experiments with this combination.

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Spectrophotometric Analysis of Dental Enamel Staining to Antiseptic and Dietary Agents: In Vitro Study

International Journal of Dentistry ◽

10.1155/2020/5429725 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Mukhatar Ahmed Javali ◽

Mohasin Abdul Khader ◽

Razan Mansour Alqahtani ◽

Muna Jubran Almufarrij ◽

Thamra Mohammed Alqahtani ◽

...

Keyword(s):

Dental Enamel ◽

In Vitro Study ◽

Spectrophotometric Analysis ◽

Distilled Water ◽

Water Control ◽

Calculus Formation ◽

The Difference ◽

Dietary Agents

Background/Objectives. Use of antiseptics as an adjunct to a traditional mechanical tooth brushing method has limited their application for long duration because of their side effects such as staining and calculus formation. The objective of this in vitro study is to analyse the staining effects of antiseptic mouthwashes on dental enamel and compare it with those containing nanoparticles, dietary agents, and distilled water (control). Material and Methods. 105 intact premolars extracted for orthodontic reasons and without any caries or anatomical defects were selected for analysis. The samples were randomly divided into 7 different groups of fifteen teeth each for different solutions. A spectrophotometer was used to assess the colorimeter analysis of buccal dental enamel surface at R1 (baseline examination), R2 (24 hours after immersion in different solutions), and R3 (after brushing). Statistical analysis was done using the Kolmogorov–Smirnov test and Levene’s test (p<0.05), respectively. One-way ANOVA was used to compare the difference in color (∆E) between the readings, R1, R2, and R3. Results. The mouthwash containing titanium dioxide (TiO2) nanoparticles produced the greater enamel discoloration compared to that of chlorhexidine. Brushing had little effect on removal of stains induced by all mouthwashes except for dietary solutions (lemon with sodium bicarbonate and olive with laurel) and distilled water (control). Conclusion. The results from this study show that mouthwashes containing TiO2 nanoparticles and other antiseptic mouthwashes cause change in color of the teeth and lead to poor esthetic appearance when compared to dietary and control solutions. Thus, future in vivo studies have to be conducted to confirm these findings as in vitro studies may not provide a reliable simulation of the clinical situations.

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Molecular cloning and analysis of in vivo expression of murine P- selectin

Blood ◽

10.1182/blood.v80.3.795.795 ◽

1992 ◽

Vol 80 (3) ◽

pp. 795-800 ◽

Cited By ~ 104

Author(s):

WE Sanders ◽

RW Wilson ◽

CM Ballantyne ◽

AL Beaudet

Keyword(s):

Molecular Cloning ◽

Adhesion Molecule ◽

Cellular Response ◽

Tissue Injury ◽

Amino Acid Identity ◽

Mrna Levels ◽

Surface Adhesion ◽

New Synthesis

Abstract P-selectin (CD62) is a rapidly inducible cell surface adhesion molecule that is expressed on platelets and endothelial cells and mediates their interaction with leukocytes. In vitro studies have suggested that this receptor may play an important role in hemostasis and in inflammatory response to tissue injury. We report the molecular cloning and sequencing of murine cDNA for P-selectin. The lectin, epidermal growth factor (EGF)-like, transmembrane, and cytoplasmic domains are highly conserved between mouse and human, with an overall amino acid identity of 79%. To further investigate the biology of this adhesion molecule in vivo, we analyzed mRNA levels for P-selectin in mice after injection with endotoxin. Northern blot data indicate that the cellular response in vivo includes a rapid increase in the level of mRNA, presumably for new synthesis of P-selectin. The increase in mRNA is maximal at 4 hours, and turnover is relatively rapid, with levels of RNA having decreased substantially by 6 hours following stimulation with endotoxin. After administration of endotoxin, the highest levels of mRNA expression were detected in liver, lung, kidney, and heart.

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Hydroxyapatite and Carbonated Apatite as Models for the Dissolution Behavior of Human Dental Enamel

Advances in Dental Research ◽

10.1177/08959374870010022301 ◽

1987 ◽

Vol 1 (2) ◽

pp. 314-321 ◽

Cited By ~ 29

Author(s):

J.A. Budz ◽

M. Lore ◽

G.H. Nancollas

Keyword(s):

Driving Forces ◽

Dental Enamel ◽

Dissolution Behavior ◽

Constant Composition ◽

Interesting Phenomenon ◽

Carbonated Apatite ◽

Human Enamel ◽

Synthetic Hydroxyapatite ◽

Intact Surface

It is now well-established that kinetic aspects as well as considerations based solely on solubilities and thermodynamic driving forces should be taken into account while one is attempting to understand the mechanism of dental caries. In the present study, kinetic comparisons of the dissolution of hydroxyapatite, carbonated apatite, and ground human dental enamel have been made in order that the appropriateness of these synthetic phases as enamel dissolution models can be assessed. Specific additives used to form intact surface layers in vitro have also been investigated. An interesting phenomenon related to surface-controlled dissolution has been revealed. During Constant Composition experiments, the dissolution rates for all the systems decrease markedly as the reaction proceeds. Further tests with fresh crystals suggest that micro-impurities, in addition to microstructural changes of the dissolving surfaces, may play a role in the case of hydroxyapatite but do not influence the dissolution of carbonated apatite. Kinetic results for ground human enamel indicate the release of dissolution poisons. Nevertheless, the results confirm expectations that carbonated apatite may be a better model for enamel than near-stoichiometric synthetic hydroxyapatite.

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Development of Functional Screens for Dietary Angiogenesis Inhibitors

Current Developments in Nutrition ◽

10.1093/cdn/nzaa044_020 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 321-321

Author(s):

James Dunleavey ◽

St Brad Croix ◽

Nancy Emenaker ◽

Jessica Dunleavey

Keyword(s):

Mouse Models ◽

National Cancer Institute ◽

Systematic Evaluation ◽

Angiogenic Potential ◽

Angiogenesis Inhibition ◽

Sprouting Angiogenesis ◽

In Vivo Testing ◽

Dietary Agents

Abstract Objectives We sought to develop a workflow to evaluate the anti-angiogenic potential of dietary agents in a stringent, systemic manner: 1) in vitro inhibition of angiogenesis, 2) in vivo testing of normal angiogenesis inhibition, and 3) in vivo testing of tumor prevention. Methods We used a tiered workflow for assessment of anti-angiogenic potential of dietary compounds, beginning with cell culture methods, moving to high-throughput D. rerio angiogenesis modeling and finally mouse models of angiogenesis and tumor development to identify potent dietary agents which block tumor angiogenesis. Results We identified quercetin dihydrate as an orally available inhibitor of angiogenesis and our lead candidate for further evaluation for chemoprevention of angiogenesis. Quercetin blocked in vitro sprouting angiogenesis, and displayed a dose-dependent reduction in sprouting angiogenesis in the tail regeneration model in zebrafish. Finally, quercetin implanted at reported physiologic levels blocked blood vessel growth in mouse models of angiogenesis. Conclusions We describe a workflow for systematic evaluation of dietary compounds in increasing complexity models for stringent, systematic evaluation of angiogenesis inhibition. These multi-model approaches allow for filtering of pan-assay interference compounds (PAINS) prior to in vivo screening. This workflow identified quercetin as a potent inhibitor of angiogenesis which warrants further study for chemoprevention through diet. Funding Sources National Cancer Institute Division of Cancer Prevention, National Cancer Institute Center for Cancer Research.

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Targeting Fibronectin To Disrupt In Vivo Candida albicans Biofilms

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.03094-15 ◽

2016 ◽

Vol 60 (5) ◽

pp. 3152-3155 ◽

Cited By ~ 7

Author(s):

Jeniel E. Nett ◽

Jonathan Cabezas-Olcoz ◽

Karen Marchillo ◽

Deane F. Mosher ◽

David R. Andes

Keyword(s):

Candida Albicans ◽

Biofilm Formation ◽

Drug Targets ◽

Venous Catheter ◽

Surface Adhesion ◽

Inhibitory Protein ◽

Content Type ◽

Novel Target

ABSTRACTNew drug targets are of great interest for the treatment of fungal biofilms, which are routinely resistant to antifungal therapies. We theorized that the interaction ofCandida albicanswith matricellular host proteins would provide a novel target. Here, we show that an inhibitory protein (FUD) targetingCandida-fibronectin interactions disrupts biofilm formationin vitroandin vivoin a rat venous catheter model. The peptide appears to act by blocking the surface adhesion ofCandida, halting biofilm formation.

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Bidirectional induction of the cognate receptor-ligand α4/VCAM-1 pair defines a novel mechanism of tumor intravasation

Blood ◽

10.1182/blood.v95.7.2397.007k07_2397_2406 ◽

2000 ◽

Vol 95 (7) ◽

pp. 2397-2406

Author(s):

Laura Bogetto ◽

Elena Gabriele ◽

Roberta Cariati ◽

Riccardo Dolcetti ◽

Paola Spessotto ◽

...

Keyword(s):

Endothelial Cells ◽

Neutralizing Antibodies ◽

Interferon Γ ◽

Leukemic Cells ◽

Surface Adhesion ◽

T Cell Lymphomas ◽

Tumor Dissemination ◽

Macrophage Colony

Engagement of cell surface adhesion receptors with extracellular constituents and with cellular counter-receptors is crucial for the extravasation of blood-borne neoplastic cells and their seeding at distant sites; however, the early events of tumor dissemination—ie, the intravasation step(s)—have been largely neglected. A role for the 4β7 integrin was hypothesized to explain the high leukemogenicity exhibited by one (NQ22) among several T-cell lymphomas studied. To clarify the mechanisms of early aggressivity, the behavior of highly and poorly leukemogenic cell lines were compared in vitro. Cocultivation of physically separated leukemic cells with resting endothelial cells resulted in the up-regulation of VCAM-1 expression. NQ22 cells expressed mRNA of different cytokines that up-regulate VCAM-1 and at higher levels than cells of a nonaggressive lymphoma, and they migrated more efficiently through an activated endothelial cell layer. With the use of neutralizing antibodies against interferon-γ, granulocyte macrophage colony-stimulating factor, and tumor necrosis factor (TNF)-, it was determined that TNF- is one of the soluble factors released by NQ22 cells involved in the up-regulation of VCAM-1. The finding that vascular cells within the early local growth were strongly positive for VCAM-1 indicated that NQ22 cells could activate endothelial cells also in vivo. Finally, cocultivation of preleukemic 4−NQ22 cells with TNF--activated endothelial cells induced the expression of 4 integrins on the former cells. Reciprocal up-regulation and engagement of 4/VCAM-1 pairs determined the sequential transmigration and intravasation steps, and similar mechanisms might affect the aggressivity of human T lymphoblastic lymphomas.

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