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Intraoral scanners have significantly improved over the last decade. Nevertheless, data comparing intraoral digital scans with conventional impressions are sparse. The purpose of this systematic review and meta-analysis was to determine the impact of impression technique (digital scans versus conventional impressions) on the clinical time, patient comfort, and marginal fit of tooth-supported prostheses. The authors conducted a literature search based on the Population, Intervention, Comparison, and Outcome (PICO) framework in 3 databases to identify clinical trials with no language or date restrictions. The mean clinical time, patient comfort, and marginal fit values of each study were independently extracted by 2 review authors and categorized according to the scanning or impression method. The authors assessed the study-level risk of bias. A total of 16 clinical studies met the inclusion criteria. The mean clinical time was statistically similar for digital scan procedures (784 ±252 seconds) and for conventional impression methods (1125 ±159 seconds) (P >.05). The digital scan techniques were more comfortable for patients than conventional impressions; the mean visual analog scale score was 67.8 ±21.7 for digital scans and 39.6 ±9.3 for conventional impressions (P <.05). The mean marginal fit was 80.9 ±31.9 μm and 92.1 ±35.4 μm for digital scan and conventional impressions, respectively, with no statistically significant difference (P >.05). Digital scan techniques are comparable with conventional impressions in terms of clinical time and marginal fit but are more comfortable for patients than conventional impression techniques. [ABSTRACT FROM AUTHOR]

Periodontal diseases are inflammatory lesions initiated by oral bacteria and lead to the destruction of the supporting structures of the teeth (gingiva, periodontal ligament and alveolar bone) in susceptible patient. Via several biological mechanisms, periodontal diseases have been associated with multiple systemic diseases, such as rheumatoid arthritis, diabetes, cardiovascular diseases, Alzheimer's disease and adverse pregnancy outcomes. Similarly certain eye diseases have been associated with systemic diseases of the inflammatory pathway. We hypothesized that periodontal diseases are associated with eye diseases. Thus using literature data we find that several studies have reported that eye disorders are associated with the presence of periodontal diseases. But the mechanisms of this relationship are not clear. However the innate immune response involvement, the sharing of similar risk factors in pathogenesis and the changes of eye choroid thickness may be suggested as several hypotheses to explain this potential association. [ABSTRACT FROM AUTHOR]

Background: New reconstruction algorithms allow reduction in acquisition times or the amount of injected radioactivity. We examined the impact of different corrections on low-count clinical SPECT myocardial perfusion images (MPI) and compared to (82)Rb PET/CT. We compared no corrections (NC) to attenuation correction (AC) with and without scatter correction by either a dual-energy-window (AC-DEW) or model-based (AC-ESSE) approach. All reconstructions included resolution recovery.Methods: 56 patients were imaged using a standard rest/stress Tc-99m-tetrofosmin MPI SPECT/CT protocol with an additional half-time acquisition. A (82)Rb-rest/stress PET/CT MPI was acquired within 4 weeks. Reconstruction methods were compared using summed rest/stress/difference scores from an objective algorithm (SRS/SSS/SDS).Results: The SRS and SSS for NC were significantly (P < .01) higher than for AC, but well correlated (r ≥ 0.87). The correlation in SRS/SSS among AC, AC-DEW, and AC-ESSE was excellent (r ≥ 0.98). AC-ESSE and AC-DEW had higher SRS (P ≤ .05) than AC, but the SDS values were not significantly different. Concordance with PET normal/abnormal classification was 76% for NC and ≥85% for the AC methods.Conclusion: AC significantly improves the accuracy of low-count myocardial perfusion SPECT half-time imaging for the detection of disease compared to NC. Compared to PET, there was no significant difference among AC, AC-DEW, and AC-ESSE. [ABSTRACT FROM AUTHOR]

Background: New reconstruction algorithms allow reduction in acquisition times or the amount of injected radioactivity. We examined the impact of different corrections on low-count clinical SPECT myocardial perfusion images (MPI) and compared to Rb PET/CT. We compared no corrections (NC) to attenuation correction (AC) with and without scatter correction by either a dual-energy-window (AC-DEW) or model-based (AC-ESSE) approach. All reconstructions included resolution recovery. Methods: 56 Patients were imaged using a standard rest/stress Tc-99m-tetrofosmin MPI SPECT/CT protocol with an additional half-time acquisition. A Rb-rest/stress PET/CT MPI was acquired within 4 weeks. Reconstruction methods were compared using summed rest/stress/difference scores from an objective algorithm (SRS/SSS/SDS). Results: The SRS and SSS for NC were significantly ( P < .01) higher than for AC, but well correlated ( r ≥ 0.87). The correlation in SRS/SSS among AC, AC-DEW, and AC-ESSE was excellent ( r ≥ 0.98). AC-ESSE and AC-DEW had higher SRS ( P ≤ .05) than AC, but the SDS values were not significantly different. Concordance with PET normal/abnormal classification was 76% for NC and ≥85% for the AC methods. Conclusion: AC significantly improves the accuracy of low-count myocardial perfusion SPECT half-time imaging for the detection of disease compared to NC. Compared to PET, there was no significant difference among AC, AC-DEW, and AC-ESSE. [ABSTRACT FROM AUTHOR]

Background: For SPECT, CT-based attenuation correction is preferred. Many different models of CT are available with SPECT/CT systems. Our study compares clinical cardiac SPECT images that were attenuation corrected using slow-rotation CT and high-speed CT transmission scans. Methods: We evaluated 59 rest/stress perfusion studies from patients who had undergone both a SPECT/CT with a slow-rotation CT and a perfusion study on a PET/CT camera equipped with a high-speed CT scanner. Each SPECT study was reconstructed with transmission maps from both CT scans and the relative perfusion was assessed using semi-automated software. The summed stress/rest/and difference scores (SSS/SRS/SDS) were compared as well as the test classification. Results: The intraclass correlation coefficients for the SSS, SRS, and SDS were 0.97, 0.96, and 0.80 respectively. There were no significant differences in the mean SSS, SRS, or SDS with the use of either CT for attenuation corrections. Classifying SSS > 3 as abnormal, there was 97% concordance (κ = 0.88). Classifying SDS > 1 as abnormal, there was 95% concordance (κ = 0.54). A McNemar's test showed no significant differences. Conclusions: There were no significant differences between using a high-speed CT and using a slow-rotation CT for attenuation correction of SPECT myocardial perfusion images. [ABSTRACT FROM AUTHOR]

Abstract: In this contribution, two methods are presented for the removal of benzyl-type protecting groups attached to the nitrogen atom of 2-azabicyclo[3.1.0]hexane and 2-azabicyclo[4.1.0]heptane systems. The first, based on the Polonovski reaction, is suitable for [3.1.0] systems. The second relies on an elimination process, starting from derivatives of O-methyl phenylglycinol, and is more general in terms of the substrates tolerated. Secondary bicyclic cyclopropylamines, including enantiomerically pure molecules, can thus be accessed. These compounds are then ready for further functionalisation. [Copyright &y& Elsevier]

Abstract: A facile and rapid synthetic approach of N-benzyl-2-substituted piperazine building-blocks via an Ugi strategy is described. This strategy is high yielding (80–92% overall yield), step-efficient and fast using microwave heating and tert-butylisocyanide as a convertible isocyanide. This method is useful for the obtention of key intermediates in medicinal chemistry. [Copyright &y& Elsevier]

Abstract: The aim of this work is to elucidate the mechanism involved in the 3C–SiC formation during growth by a vapor–liquid–solid mechanism on 6H–SiC substrate. Polytype selection is shown to occur at the first stage of the experiments, before propane injection into the reactor. The contact of the seed with a Si–Ge melt during the initial heating ramp causes the formation of 3C–SiC islands on the seed surface, probably below 1200°C. The proposed mechanism first involves a partial dissolution of the seed in a Ge-rich liquid which becomes C-supersaturated. Then the Si content of the liquid rapidly increases, which provokes the precipitation of the dissolved carbon in the form of 3C–SiC islands. When growth starts upon propane injection, these islands enlarge and coalesce to form a continuous 3C–SiC layer. If the growth temperature is too high (⩾1550°C), the initial 3C–SiC islands are dissolved and homoepitaxial layers are obtained. [Copyright &y& Elsevier]

Abstract: The osseointegration rate of titanium dental implants is related to their composition and surface roughness. Rough-surfaced implants favor both bone anchoring and biomechanical stability. Osteoconductive calcium phosphate coatings promote bone healing and apposition, leading to the rapid biological fixation of implants. The different methods used for increasing surface roughness or applying osteoconductive coatings to titanium dental implants are reviewed. Surface treatments, such as titanium plasma-spraying, grit-blasting, acid-etching, anodization or calcium phosphate coatings, and their corresponding surface morphologies and properties are described. Most of these surfaces are commercially available and have proven clinical efficacy (>95% over 5 years). The precise role of surface chemistry and topography on the early events in dental implant osseointegration remain poorly understood. In addition, comparative clinical studies with different implant surfaces are rarely performed. The future of dental implantology should aim to develop surfaces with controlled and standardized topography or chemistry. This approach will be the only way to understand the interactions between proteins, cells and tissues, and implant surfaces. The local release of bone stimulating or resorptive drugs in the peri-implant region may also respond to difficult clinical situations with poor bone quality and quantity. These therapeutic strategies should ultimately enhance the osseointegration process of dental implants for their immediate loading and long-term success. [Copyright &y& Elsevier]

Abstract: Samarium diiodide is an efficient precatalyst for the Friedel–Crafts reaction involving various aromatic substrates and chelating electrophiles. Alkyl 3,3,3-trifluoropyruvates are transformed into α-hydroxyesters in good yields with total regioselectivity. In reactions involving an ethyl glyoxylate or a glyoxylic imine, α-hydroxyesters or α-aminoesters are obtained with variable amounts of products resulting from a double Friedel–Crafts reaction. [Copyright &y& Elsevier]

The May River, South Carolina watershed has undergone rapid increases in population and development from 1999 to 2017. This study aimed to understand the factors that influence salinity and fecal coliform levels in this estuary and how these levels changed from 1999 to 2017. This analysis revealed that salinity levels decreased in the headwaters, while variability increased. Additionally, fecal coliform increased from 1999 to 2017 throughout the hydrological network, with drastic changes occurring in the headwaters. Salinity and fecal coliform were influenced by spatial (distance from the mouth of the river), temporal (year, season, and tidal cycles), environmental (El Niño Southern Oscillation and rainfall), and anthropogenic parameters (population). This analysis suggests that the synergistic nature of climate change, resulting in more intense and frequent El Niño events, and watershed development may lead to further decreases in salinity and increases in fecal coliform levels in the May River estuary. • From 1999 to 2017, salinity levels decreased and variability increased in the headwaters of the May River, South Carolina. • From 1999 to 2017, fecal coliform levels increased dramatically in the headwaters of the estuary. • Fecal coliform correlated positively with rainfall, population, and El Niño but negatively with salinity. • Increasing development and more frequent, intense El Niño episodes may lead to further degradation of the May River. [ABSTRACT FROM AUTHOR]

Le nombre de cas d’ostéonécroses des mâchoires est en constante augmentation. Certaines surviennent chez des patients traités par bisphosphonates oraux pour ostéoporose ou maladie de Paget, mais la plupart concerne des patients traités par bisphosphonates par voie intraveineuse dans le cadre d’un traitement oncologique. La prise en charge est pluridisciplinaire. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is to determine periodontal disease''s prevalence in preterm delivery (before 37weeks of gestation) and find a significant association between preterm birth and periodontal diseases. Periodontal status was determined. Status and severity were noted and correlated to term of delivery. Fifty-two patients were included in the study. Periodontal disease''s prevalence was 33% for gingivitis and 44% for periodontitis. No significant correlation was found (P =0.41). Periodontal disease''s prevalence is agreed with litterature review. The different opinion are largely discussed. Methodological harmonization of periodontal definitions is needed to increase study''s power. [Copyright &y& Elsevier]

Abstract: The reductive coupling of imines in the presence of the lanthanide-originated zirconocene equivalent allows the synthesis of vicinal diamines or imidazolidines under mild conditions in good yields with high diastereoselectivity. [Copyright &y& Elsevier]

Abstract: Trimethylvinylsilane and disubstituted alkynes underwent coupling reactions in the presence of the lanthanide-originated zirconocene equivalent. Both reactions, stoichiometric and catalytic in zirconium, could be carried out; in the latter case the addition of a stoichiometric amount of AlCl3 was needed. The catalytic cycle involving bimetallic polarization and a transmetallation step has been proposed. [Copyright &y& Elsevier]

Periodontal pockets are the major clinical manifestation of Periodontitis, a chronic inflammatory oral disease affecting the teeth-supporting tissues and has high prevalence in the adult population. Periodontal pockets are ideal environments for subgingival bacterial biofilms, that interact with the supragingival oral cavity, mucosal tissues of the pocket and a peripheral circulatory system. Periodontal pockets have been found to harbor viral species such as the Herpes simplex viruses' family. Recently, the SARS-CoV-2 has gained major interest of the scientific/medical community as it caused a global pandemic (Covid-19) and paralyzed the globe with high figures of infected people worldwide. This virus behavior is still partially understood, and by analyzing some of its features we hypothesized that periodontal pocket could be a favorable anatomical niche for the virus and thus acting as a reservoir for SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Periodontitis is an oral inflammatory disease affecting the teeth supportive tissue. Its bacterial infectious etiology is well established. Periodontitis has been associated with increased prevalence of systemic diseases such as cardiovascular diseases, diabetes, rheumatoid arthritis, preeclampsia, preterm birth and inflammatory bowel disease. The rational of considering periodontitis as risk factor for systemic disease is the passage of inflammatory cytokines and/or bacteria in the bloodstream, thus affecting distant organs. Membrane microparticles are released by multiple cells in inflammatory environment. Recent data suggested the role of these microparticles in the pathogenic process of many systemic diseases, that can be also associated to periodontitis. We hypothesized that periodontitis could be a chronic reservoir of microparticles, hence elucidating partially the interaction with systemic diseases initiation or progression. [ABSTRACT FROM AUTHOR]

Abstract: An efficient method for a stereoselective synthesis of optically pure N-Boc-3-arylpiperazines has been developed. After optimization of the protecting group strategy and experimental conditions, compounds were obtained via a highly stereoselective synthesis in up to 45% overall yield. This is a practical route to optically pure piperazines for medicinal chemistry. [Copyright &y& Elsevier]

One type of gem-bisphosphonate (Zoledronate) has been chemically associated onto calcium phosphate (CaP) compounds of various compositions. For that purpose, CaP powders of controlled granulometry have been suspended in aqueous Zoledronate solutions of variable concentrations. Using mainly 31P NMR spectroscopy, two different association modes have been observed, according to the nature of the CaP support and/or the initial concentration of the Zoledronate solution. β-tricalcium phosphate (β-TCP) and mixtures of hydroxyapatite and β-TCP (BCPs) appear to promote Zoledronate-containing crystals formation. On the other hand, at concentrations <0.05 mol l-1 CDAs (calcium deficients apatites) seem to undergo chemisorption of the drug through a surface adsorption process, due to PO3 for PO4 exchange, that is well described by Freundlich equations. At concentrations >0.05 mol l-1, crystalline needles of a Zoledronate complex form onto the CDAs surface. The ability of such materials to release Zoledronate, resulting in the inhibition of osteoclastic activity, was shown using a specific in vitro bone resorption model. [Copyright &y& Elsevier]

Abstract: A Passerini three component condensation between a carboxylic acid, an aldehyde, and an isocyanide at high temperature under solvent-free conditions was developed. This methodology allows the formation of a broad range of α-acyloxyamides in excellent yields in short reaction times. [Copyright &y& Elsevier]

The stability and reliability at high temperature of Ti 3 SiC 2 based ohmic contacts on p-type 4H-SiC (0001) 4°-off substrates were studied. The contact was grown from Ti 100-x Al x alloys annealed at high temperature (from 900 °C to 1200 °C). The Specific Contact Resistance (SCR) at room temperature and at high temperature (up to 600 °C) was in the 10−4–10−5 Ω.cm2 range. A Schottky barrier height of 0.71 to 0.85 eV was calculated for the set of samples. After aging period at 600 °C for 1500 h, the SCR was very stable for Al contents x < 80 at.%. This was correlated with chemical and physical stability of these contacts, where the residual stress located on 4H-SiC/Ti 3 SiC 2 interface decreased after aging, for which the Ti 3 SiC 2 phase was preserved. Whereas, in the case of x = 80 at.%, the Ti 3 SiC 2 phase disappeared and the contacts were not ohmic anymore after long time aging. The obtained results showed that Ti 3 SiC 2 /4H-SiC system is thermodynamically stable at high temperatures and can therefore be a good candidate, with high potential, for high power and high temperature electronic applications. • Stable and reliable electrical contacts on silicon carbide for high power applications • Low and stable electrical resistivity in Ti3SiC2-based contact on silicon carbide • MAX phase-based contact on silicon carbide is physically stable at high temperatures. [ABSTRACT FROM AUTHOR]

Lead-free Bi 0.5 Na 0.5 TiO 3 (BNT) piezoelectric thin films were deposited on Pt/TiO x /SiO 2 /Si substrates by Sol-Gel method. A dense and well crystallized thin film with a perovskite phase was obtained by annealing the film at 700 °C in a rapid thermal processing system. The relative dielectric constant and loss tangent at 12 kHz, of BNT thin film with 350 nm thickness, were 425 and 0.07, respectively. Ferroelectric hysteresis measurements indicated a remnant polarization value of 9 μC/cm 2 and a coercive field of 90 kV/cm. Piezoelectric measurements at the macroscopic level were also performed: a piezoelectric coefficient (d 33effmax ) of 47 pm/V at E = 190 kV/cm was obtained. The piezoresponse force microscopy data confirmed that BNT thin films present ferroelectric and piezoelectric behavior at the nanoscale level. [ABSTRACT FROM AUTHOR]

The objective of this work is to define the conditions for improving the use of laser Doppler flowmetry (LDF) and to determine the limits for the use of this technique. This article systematically reviews the literature on the evaluation of oral soft tissue blood microcirculation by LDF. We analysed the available literature through October 2016 using the database resources Medline/PubMed, the Cochrane Oral Health Group Specialist Trials Register and the ISI Web of Knowledge. Several points emerged from this literature review The use of LDF involves specific constraints; however, the influence of different factors (temperature, tobacco, pressure etc.) must be adequately controlled when using LDF. LDF measurements of soft tissue within the oral cavity vary depending on the anatomical site. In dentistry, LDF can be used to track healing progress in periodontal surgery and to diagnose vascular flow changes in the connective tissue of mucosae covered by a removable prosthesis at an early stage prior to the onset of clinical inflammation signs. [ABSTRACT FROM AUTHOR]

Reelin and its receptor, ApoER2, play important roles in prenatal brain development and postnatally in synaptic plasticity, learning, and memory. Previous reports suggest that reelin's central fragment binds to ApoER2 and receptor clustering is involved in subsequent intracellular signaling. However, limitations of currently available assays have not established cellular evidence of ApoER2 clustering upon binding of the central reelin fragment. In the present study, we developed a novel, cell-based assay of ApoER2 dimerization using a "split-luciferase" approach. Specifically, cells were co-transfected with one recombinant ApoER2 receptor fused to the N-terminus of luciferase and one ApoER2 receptor fused to the C-terminus of luciferase. Using this assay, we directly observed basal ApoER2 dimerization/clustering in transfected HEK293T cells and, significantly, an increase in ApoER2 clustering in response to that central fragment of reelin. Furthermore, the central fragment of reelin activated intracellular signal transduction of ApoER2, indicated by increased levels of phosphorylation of Dab1, ERK1/2, and Akt in primary cortical neurons. Functionally, we were able to demonstrate that injection of the central fragment of reelin rescued phenotypic deficits observed in the heterozygous reeler mouse. These data are the first to test the hypothesis that the central fragment of reelin contributes to facilitating the reelin intracellular signaling pathway through receptor clustering. • Development of ApoER2 dimerization/clustering assay • Reelin central fragment R3456 can dimerize ApoER2 and cause Dab1 phosphorylation. • R3456 activates ERK1/2 via SRK and PI3K, and it activates Akt via PI3K and SRK. • R3456 rescues cognitive deficits in the HRM model. [ABSTRACT FROM AUTHOR]

Résumé: Objectifs: L’abondance d’études récentes sur la relation entre les affections buccodentaires et les complications de grossesse conduit à s’interroger sur les connaissances des professionnels de santé sur ce sujet. Cette étude a pour objectif d’établir un état des lieux des connaissances et des pratiques des professionnels de santé en France sur ce sujet. Patientes et méthodes: Un questionnaire portant sur les connaissances des relations entre pathologies buccodentaires et grossesse a été adressé à des gynécologues-obstétriciens, sages-femmes et chirurgiens-dentistes (CD). Cette étude a été réalisée au centre hospitalier universitaire (CHU) de Nantes et à l’hôpital général du Mans. Résultats: Quatre-vingt-sept rofessionnels de grossesse et 259 CD ont répondu au questionnaire. Les saignements gingivaux et la gingivite gravidique sont les manifestations buccodentaires les plus citées par tous les praticiens. Alors que les résultats concernant le risque carieux et l’épulis diffèrent selon les spécialités. Les complications de grossesse les plus citées sont la menace d’accouchement prématuré et la chorioamniotite. Seuls les CD avaient reçu une formation initiale sur les complications de grossesse. Enfin, l’ensemble des professionnels de santé soulignent l’absence de formation continue sur ce sujet. Discussion et conclusion: Il existe une bonne connaissance des complications de grossesse liées aux maladies buccodentaires malgré l’absence de formation des professionnels de la grossesse (PG), qui ne traduisent pas une prise en charge optimale. Il apparaît nécessaire de renforcer la formation de tous les praticiens dans ce domaine. La conception et la mise en place d’un questionnaire spécifique sur l’état buccodentaires pourrait permettre une meilleure identification des patientes à risque par les PG, et optimiser ainsi la prise en charge des femmes enceintes. [ABSTRACT FROM AUTHOR]

The structure-specific ERCC1-XPF endonuclease is essential for repairing bulky DNA lesions and helix distortions induced by UV radiation, which forms cyclobutane pyrimidine dimers (CPDs), or chemicals that crosslink DNA strands such as cyclophosphamide and platinum-based chemotherapeutic agents. Inhibition of the ERCC1-XPF endonuclease activity has been shown to sensitize cancer cells to these chemotherapeutic agents. In this study, we have conducted a structure activity relationship analysis based around the previously identified hit compound, 4-((6-chloro-2-methoxyacridin-9-yl)amino)-2-((4-methylpiperazin1-yl)methyl)phenol (F06), as a reference compound. Three different series of compounds have been rationally designed and successfully synthesized through various modifications on three different sites of F06 based on the corresponding suggestions of the previous pharmacophore model. The in vitro screening results revealed that 2-chloro-9-((3-((4-(2-(dimethylamino)ethyl)piperazin-1-yl)methyl)-4-hydroxyphenyl)amino)acridin-2-ol (B9) has a potent inhibitory effect on the ERCC1-XPF activity (IC 50 = 0.49 μM), showing 3-fold improvement in inhibition activity compared to F06. In addition, B9 not only displayed better binding affinity to the ERCC1-XPF complex but also had the capacity to potentiate the cytotoxicity effect of UV radiation and inhibiting the nucleotide excision repair, by the inhibition of removal of CPDs, and cyclophosphamide toxicity to colorectal cancer cells. Image 1 • A series of ERCC1-XPF generations was developed by structure-based design. • 24 compounds were synthesized via a facile route, and their in vitro inhibition of ERCC1-XPF endonuclease activity was successfully assessed. • B9 elicits a potent inhibitory effect on ERCC1-XPF activity, and higher binding affinity relative to the reference compound F06. • B9 sensitized colorectal cancer cells to treatment with cyclophosphamide and UV radiation. [ABSTRACT FROM AUTHOR]