34 research outputs found

    Piezosebészeti eszköz és a sagittalis csontfűrész intraossealis hőtermelésének in vitro összehasonlító vizsgálata.

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    Vizsgálatunkban in vitro körülmények között összehasonlítottuk a piezosebészeti eszköz és a sagittalis csontfűrész által termelt hőmennyiséget. Sertésbordába K-típusú hőérzékelőt rögzítettünk, amitől 1 mm távolságra, "legyezőszerű" folyamatos mozgással 30-30 bordát vágtunk át sagittalis fűrésszel (S-8 S - Elcomed, W&H) és piezosebészeti eszközzel (B6 - Piezomed, W&H). Utóbbival hűtési ciklusokat közbeiktatva 30 mintán szakaszos vágást is végeztünk. Sagittalis fűrésszel végzett osteotomia során nem mértünk 47°C feletti értéket. Piezoelektromos eszközzel "legyezőszerű", folyamatos mozgással végzett vágás mellett a mérési eredmények 16,2 +- 3,53%-a elérte a kritikus hőmérséklet-értéket, hűtési ciklusok közbeiktatásával ez az érték 2,6 +- 0,96%-ra csökkent (p < 0.001). A hőmérséklet egyetlen esetben sem haladta meg a 47°C-ot több mint 20 másodpercig. A piezosebészeti eszköz biztonságosan használható, azonban az osteonecrosis kialakulásának esélyét tovább csökkenthetjük hűtési ciklusok közbeiktatásával, intermittáló műszerhasználattal és maximális vízhűtéssel

    Assessment of putative protein targets derived from the SARS genome

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    AbstractThe ability to rapidly and reliably develop hypotheses on the function of newly discovered protein sequences requires systematic and comprehensive analysis. Such an analysis, embodied within the DS GeneAtlas™ pipeline, has been used to critically evaluate the severe acute respiratory syndrome (SARS) genome with the goal of identifying new potential targets for viral therapeutic intervention. This paper discusses several new functional hypotheses on the roles played by the constituent gene products of SARS, and will serve as an example of how such assignments can be developed or extended on other systems of interest

    Effect of Ceramic and Dentin Thicknesses and Type of Resin-Based Luting Agents on Intrapulpal Temperature Changes during Luting of Ceramic Inlays

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    The adhesive cementation of ceramic inlays may increase pulpal temperature (PT) and induce pulpal damage due to heat generated by the curing unit and the exothermic reaction of the luting agent (LA). The aim was to measure the PT rise during ceramic inlay cementation by testing different combinations of dentin and ceramic thicknesses and LAs. The PT changes were detected using a thermocouple sensor positioned in the pulp chamber of a mandibular molar. Gradual occlusal reduction obtained dentin thicknesses of 2.5, 2.0, 1.5, and 1.0 mm. Light-cured (LC) and dual-cured (DC) adhesive cements and preheated restorative resin-based composite (RBC) were applied to luting of 2.0, 2.5, 3.0, and 3.5 mm lithium disilicate ceramic blocks. Differential scanning calorimetry was used to compare the thermal conductivity of dentin and ceramic slices. Although ceramic reduced heat delivered by the curing unit, the exothermic reaction of the LAs significantly increased it in each investigated combination (5.4-7.9 °C). Temperature changes were predominantly influenced by dentin thickness followed by LA and ceramic thickness. Thermal conductivity of dentin was 24% lower than that of ceramic, and its thermal capacity was 86% higher. Regardless of the ceramic thickness, adhesive inlay cementation can significantly increase the PT, especially when the remaining dentin thickness is <2 mm

    Pre-Heating Effect on Monomer Elution and Degree of Conversion of Contemporary and Thermoviscous Bulk-Fill Resin-Based Dental Composites

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    Detection of unreacted monomers from pre-heated resin-based dental composites (RBC) is not a well-investigated topic so far. The objectives were to determine the temperature changes during the application and polymerization, the degree of conversion (DC) and unreacted monomer elution of room temperature (RT), and pre-heated thermoviscous [VisCalor Bulk(VCB)] and high-viscosity full-body contemporary [Filtek One Bulk(FOB)] bulk-fill RBCs. The RBCs' temperatures during the sample preparation were recorded with a K-type thermocouple. The DC at the top and bottom was measured with micro-Raman spectroscopy and the amounts of eluted BisGMA, UDMA, DDMA, and TEGDMA were assessed with High-Performance Liquid Chromatography. The temperatures of the pre-heated RBCs decreased rapidly during the manipulation phase. The temperature rise during photopolymerization reflects the bottom DCs. The differences in DC% between the top and the bottom were significant. RT VCB had a lower DC% compared to FOB. Pre-heating did not influence the DC, except on the bottom surface of FOB where a significant decrease was measured. Pre-heating significantly decreased the elution of BisGMA, UDMA, DDMA in the case of FOB, meanwhile, it had no effect on monomer release from VCB, except TEGDMA, which elution was decreased. In comparison, RBC composition had a stronger influence on DC and monomer elution, than pre-cure temperature

    The effect of high-irradiance rapid polymerization on degree of conversion, monomer elution, volumetric change and porosity of bulk-fill resin composites

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    The purpose was to compare the degree of conversion (DC), monomer elution (ME), polymerization shrinkage (PS) and porosity of two addition-fragmentation chain transfer (AFCT) modified resin-based composites (RBC) light-cured with rapid- (RP), turbo- (TP) or conventional polymerization (CP) settings.Cylindrical samples (6-mm wide, 4-mm thick) were prepared from Tetric PowerFill (TPF) and Filtek One Bulk (FOB). Four groups were established according to the polymerization settings: 3s-RP, 5s-TP, 10s-CP and 20s-CP. Samples in 1 mm thickness with 20s-CP settings served as controls. The DC at the top and bottom surfaces was measured with micro-Raman spectroscopy. ME was detected with high-performance liquid chromatography. PS and porosity were analyzed by micro-computed tomography. ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics were used to analyze the data (p < 0.05).FOB showed higher DC values (61.5-77.5 %) at the top compared to TPF (43.5-67.8 %). At the bottom TPF samples achieved higher DCs (39.9-58.5 %) than FOB (18.21-66.18 %). Extending the curing time increased DC (except the top of FOB) and decreased ME. BisGMA release was the highest among the detected monomers from both RBCs. The amount was three-fold more from TPF. The factor Material and Exposure significantly influenced DC and ME. PS (1.8-2.5 %) did not differ among the groups and RBCs except for the lowest value of TPF cured with the 3s_RP setting (p = 0.03). FOB showed 4.5-fold lower porosity (p < 0.001). Significantly higher pore volume was detected after polymerization in 3s_RP (p < 0.001).High-irradiance rapid 3-s curing of AFCT modified RBCs resulted in inferior results for some important material properties. A longer exposure time is recommended in a clinical situation

    Effective knowledge management in translational medicine

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    <p>Abstract</p> <p>Background</p> <p>The growing consensus that most valuable data source for biomedical discoveries is derived from human samples is clearly reflected in the growing number of translational medicine and translational sciences departments across pharma as well as academic and government supported initiatives such as Clinical and Translational Science Awards (CTSA) in the US and the Seventh Framework Programme (FP7) of EU with emphasis on translating research for human health.</p> <p>Methods</p> <p>The pharmaceutical companies of Johnson and Johnson have established translational and biomarker departments and implemented an effective knowledge management framework including building a data warehouse and the associated data mining applications. The implemented resource is built from open source systems such as i2b2 and GenePattern.</p> <p>Results</p> <p>The system has been deployed across multiple therapeutic areas within the pharmaceutical companies of Johnson and Johnsons and being used actively to integrate and mine internal and public data to support drug discovery and development decisions such as indication selection and trial design in a translational medicine setting. Our results show that the established system allows scientist to quickly re-validate hypotheses or generate new ones with the use of an intuitive graphical interface.</p> <p>Conclusions</p> <p>The implemented resource can serve as the basis of precompetitive sharing and mining of studies involving samples from human subjects thus enhancing our understanding of human biology and pathophysiology and ultimately leading to more effective treatment of diseases which represent unmet medical needs.</p

    Anti-calmodulins and Tricyclic Adjuvants in Pain Therapy Block the TRPV1 Channel

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    Ca2+-loaded calmodulin normally inhibits multiple Ca2+-channels upon dangerous elevation of intracellular Ca2+ and protects cells from Ca2+-cytotoxicity, so blocking of calmodulin should theoretically lead to uncontrolled elevation of intracellular Ca2+. Paradoxically, classical anti-psychotic, anti-calmodulin drugs were noted here to inhibit Ca2+-uptake via the vanilloid inducible Ca2+-channel/inflamatory pain receptor 1 (TRPV1), which suggests that calmodulin inhibitors may block pore formation and Ca2+ entry. Functional assays on TRPV1 expressing cells support direct, dose-dependent inhibition of vanilloid-induced 45Ca2+-uptake at µM concentrations: calmidazolium (broad range)≥trifluoperazine (narrow range)>chlorpromazine/amitriptyline>fluphenazine>>W-7 and W-13 (only partially). Most likely a short acidic domain at the pore loop of the channel orifice functions as binding site either for Ca2+ or anti-calmodulin drugs. Camstatin, a selective peptide blocker of calmodulin, inhibits vanilloid-induced Ca2+-uptake in intact TRPV1+ cells, and suggests an extracellular site of inhibition. TRPV1+, inflammatory pain-conferring nociceptive neurons from sensory ganglia, were blocked by various anti-psychotic and anti-calmodulin drugs. Among them, calmidazolium, the most effective calmodulin agonist, blocked Ca2+-entry by a non-competitive kinetics, affecting the TRPV1 at a different site than the vanilloid binding pocket. Data suggest that various calmodulin antagonists dock to an extracellular site, not found in other Ca2+-channels. Calmodulin antagonist-evoked inhibition of TRPV1 and NMDA receptors/Ca2+-channels was validated by microiontophoresis of calmidazolium to laminectomised rat monitored with extracellular single unit recordings in vivo. These unexpected findings may explain empirically noted efficacy of clinical pain adjuvant therapy that justify efforts to develop hits into painkillers, selective to sensory Ca2+-channels but not affecting motoneurons
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