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Purpose: Vortioxetine an anti-depressant FDA-drug recently reported showing better in vitro efficacy against SARS-CoV-2. Methods: In this study, we have synthesized ten new derivatives having alkenes, alkynes, benzyl, aryl, and mixed carbamate at the N-terminal of vortioxetine. Then the binding energy and interactions with the crucial amino acid residues in the binding pocket of main protease (Mpro) of SARS-CoV-2, of reported and ten newly synthesized vortioxetine derivatives (total thirty-one) in comparison with remdesivir are analyzed and presented in this paper. Results: Based on the docking scores predicted by ADV and AD, most vortioxetine derivatives showed better binding efficiency towards Mpro of SARS-CoV-2 in comparison with remdesivir (an EUA approved drug against SARS-CoV-2 Mpro) and vortioxetine. Conclusion: This study shows that some vortioxetine derivatives can be developed into promising drugs for COVID-19 treatment. [ABSTRACT FROM AUTHOR]

This paper presents the largest cohort to date of infants under 1 year of age treated with mebendazole. We evaluated the occurrence of mebendazole-associated clinical and laboratory toxicity as safety data in this age group are currently lacking. [ABSTRACT FROM AUTHOR]

Desmodium canum (Strong back) commonly consumed as a tea or tonic is believed to possess hypoglycaemic activity. This paper sets out to isolate potential hypoglycaemic compounds present within the plant and investigate their synergistic effects on blood glucose levels in euglycaemic Sprague Dawley rats. The milled plant was sequentially extracted using hexane, ethyl acetate and methanol. The ethyl acetate extract was subjected to column chromatography yielding seven major fractions and were subsequently bioassayed using the Oral Glucose Tolerance Test (OGTT). Further chromatographic separation and analysis using Gas Chromatography–Mass Spectroscopy and Fourier Transform Infrared Spectroscopy enabled the identification of two hypoglycaemic compounds, oleic acid (OA) and succinic acid (SA). These were bioassayed individually and as a cocktail to determine the synergistic effects using OGTT. Intravenous administration of these compounds individually indicated both are very potent in retarding blood glucose levels. However, the most significant activity was observed on synergistic administration. The cocktail (1 : 1) displayed significant hypoglycaemic activity throughout the entire study. It also significantly differed from OA at the 120 min interval (3.43 ± 0.22 mmol/L vs. 4.98 ± 0.19 mmol/L, resp., p = 4.29 × 10 − 7 ) and significantly differed from SA at 30 min (3.95 ± 0.43 mmol/L vs. 5.17 ± 0.32 mmol/L, resp., p = 0.003), 90 min (4.35 ± 0.36 mmol/L vs. 5.49 ± 0.69 mmol/L, resp., p = 0.04), and 120 min intervals (3.43 ± 0.22 mmol/L vs. 4.94 ± 0.31, resp., p = 1.54 × 10 − 5 ). Oral administration of the cocktail showed comparable potency to that of metformin (p > 0.05) throughout the OGTT curve. The synergistic effects of the naturally isolated compounds yielded higher potency levels than individual administration and when administered orally, the hypoglycaemic effect was similar to that of metformin. This may assist in paving a way to attempt a novel method in approaching antidiabetic therapy. [ABSTRACT FROM AUTHOR]

Problems of stability were found for biomarkers of alcohol consumption: ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanols (PEths), and fatty acid ethyl esters (FAEEs) in whole blood. The purpose of this study was to establish a method for the determination of these four kinds of ethanol's non-oxidative metabolites in dried blood spots (DBS) by liquid chromatography tandem mass spectrometry (LC-MS/MS), and to evaluate their stability. In this method, 50 μL of human blood was spotted onto a filter paper for DBS analysis. Samples were extracted by methanol, reconstituted by 2-propanol, and injected into the LC-MS/MS system. Limits of detection were among 0.5-50 ng/mL, and deviations in accuracy and precision were all lower than 15% at three quality control levels. The stability of the four kinds of ethanol non-oxidative metabolites in DBS was investigated during a 90-day range under three temperatures, -20 °C, 4 °C, and 25 °C. EtG and EtS showed a high level of stability in DBS in the 90-day range, regardless of the temperature. FAEEs were unstable after three days. PEths showed stability within 15 days in postmortem DBS and 60 days in antemortem DBS, respectively, at all temperatures. [ABSTRACT FROM AUTHOR]

Background: Bisphenol A (BPA) is a ubiquitous, endocrine-disrupting environmental contaminant that increases risk of some adverse developmental effects. Thus, it is important to characterize BPA levels, metabolic fate and sources of exposure in pregnant women.Methods: We used an improved liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytic method to directly and simultaneously measure unconjugated BPA (uBPA), BPA glucuronide and BPA sulfate in the urine of a population of ethnically and racially diverse, and predominately low-income pregnant women (n = 112) in their second trimester. We also administered a questionnaire on dietary and non-dietary sources of exposure to BPA.Results: We found universal and high exposure to uBPA and its metabolites: median concentrations were 0.25, 4.67, and 0.31 μg/g creatinine for uBPA, BPA glucuronide, and BPA sulfate, respectively. The median Total BPA (uBPA + BPA in glucuronide and sulfate forms) level was more than twice that measured in U.S. pregnant women in NHANES 2005-2006, while 30 % of the women had Total BPA levels above the 95th percentile. On average, Total BPA consisted of 71 % BPA in glucuronide form, 15 % BPA in sulfate form and 14 % uBPA, however the proportion of BPA in sulfate form increased and the proportion of uBPA decreased with Total BPA levels. Occupational and non-occupational contact with paper receipts was positively associated with BPA in conjugated (glucuronidated + sulfated) form after adjustment for demographic characteristics. Recent consumption of foods and beverages likely to be contaminated with BPA was infrequent among participants and we did not observe any positive associations with BPA analyte levels.Conclusion: The high levels of BPA analytes found in our study population may be attributable to the low-income status of the majority of participants and/or our direct analytic method, which yields a more complete evaluation of BPA exposure. We observed near-universal exposure to BPA among pregnant women, as well as substantial variability in BPA metabolic clearance, raising additional concerns for effects on fetal development. Our results are consistent with studies showing thermal paper receipts to be an important source of exposure, point to the difficulty pregnant women have avoiding BPA exposure on an individual level, and therefore underscore the need for changes in BPA regulation and commerce. [ABSTRACT FROM AUTHOR]

This paper firstly describes the synthesis of a series of ( Z )-4-((3-chloro-4-fluorophenyl)amino)-1,1,1-trifluorobut-3-en-2-ones ( 3a–f ) as well as 1-(1-((3-chloro-4-fluorophenyl)amino)-3,4-dihydronaphthalen-2-yl)-2,2,2-trifluoroethanone ( 3g ), from the O,N-exchange reaction of some 4-methoxy-4-alkyl(aryl)-1,1,1-trifluoroalk-3-en-2-ones ( 1 ) with 3-chloro-4-fluoroaniline ( 2 ), at 70–90% yields. Subsequently, in concentrated sulfuric acid, the enaminoketones 3 underwent a successful and regioselective intramolecular cyclocondensation reaction, which furnished a novel series of 2-alkyl(aryl)-7-chloro-6-fluoro-4-(trifluoromethyl)-quinolines ( 4 ) at 70–85% yields. To demonstrate synthetic applicability through the Sonogashira coupling reaction for obtaining quinolines with potential antimicrobial activity, the synthesis of a novel series of 2-alkyl(aryl)-6-fluoro-7-(phenylethynyl)-4-(trifluoromethyl)-quinolines ( 5 ) was performed, using quinolines 4 and phenylacetylene, via a regioselective Sonogashira coupling reaction (25–50% yield). Unfortunately, the new series of heterocycles 4 and 5 did not produce significant results against bacteria and fungi at the concentrations of 80–0.31 μg/mL. [ABSTRACT FROM AUTHOR]

Rationale, aims, and objectives The United States is in the midst of a public health epidemic with more than 40 people dying each day from prescription opioid overdoses. Health care systems are taking steps to address the opioid overdose epidemic by implementing policy and practice interventions to mitigate the risks of long-term opioid therapy. Kaiser Permanente Southern California launched a comprehensive initiative to transform the way that chronic pain is viewed and treated. Kaiser Permanente Southern California created prescribing and dispensing policies, monitoring and follow-up processes, and clinical coordination through electronic health record integration. The purpose of this paper is to describe the implementation of these interventions and assess the impact of this set of interventions on opioid prescribing. Method The study used a retrospective pre-post evaluation design to track outcomes before and after the intervention. Kaiser Permanente Southern California members age 18 and older excluding cancer, hospice, and palliative care patients and this sub-population of 3 203 880 was approximately 75% of all Kaiser Permanente Southern California members. All data are from Kaiser Permanente's pharmacy data systems and electronic health record collected on a rolling basis as interventions were implemented from January 2010 to December 2015. Results There were reductions in all tracked outcomes: a 30% reduction in prescribing opioids at high doses; a 98% reduction in the number of prescriptions with quantities greater than 200 pills; a 90% decrease in the combination of an opioid prescription with benzodiazepines and carisoprodol; a 72% reduction in the prescribing of Long Acting/Extended Release opioids; and a 95% reduction in prescriptions of brand name opioid-acetaminophen products. In addition, methadone prescribing did not increase during this period. Conclusions This study adds promising results that a comprehensive system-level strategy has the ability to positively affect opioid prescribing. The basic components of the intervention are generalizable and applicable to other health care settings. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) are ubiquitous contaminants found worldwide, including in South Korea. As a result, they are frequently detected in Koreans. However, there is limited representative data and information on potential sources in Korea. Therefore, we measured the serum concentrations of ten PFASs in nationally representative samples of the Korean population (n=1874, 18-69 years) and evaluated the factors associated with their exposure. Serum PFOS, PFDA, PFOA, and PFNA were detected in nearly all participants (83.1-99.9%). However, serum PFPA, PFHxA, and PFHpA were almost undetected (<0.5% of participants). PFOS had the highest population-weighted geometric mean of 10.23ng/mL (95% CI: 9.99-10.47), which was followed by PFOA with 2.85ng/mL (95% CI: 2.73-2.97) and PFDA with 2.17ng/mL (95% CI: 2.12-2.23). PFNA, PFDA, PFHxS, PFOA, and PFOS concentrations were higher in males (p<0.001) and older adults (p<0.001). PFNA was higher in those who used wax, polish, and water-resistant materials (adjusted proportional change=1.14; 95% CI: 1.08-1.22), and those who ate cooked fish (1.16; 95% CI: 1.03-1.31) compared to those who ate nearly no fish. PFDA was higher in those who used herbicides and pesticides (1.05; 95% CI: 1.02-1.09), those who drank beverages in a plastic bag on a daily basis (1.10; 95% CI: 1.03-1.19), and those who ate raw fish (1.15; 95% CI: 1.03-1.29) or cooked fish (1.13; 95% CI: 1.05-1.23) compared to those who ate nearly no fish. PFHxS was higher in those who used traditional Korean health supplement foods (1.08; 95% CI: 1.01-1.15). PFOA was higher in those who used plastic wrap in a microwave daily or weekly (1.08; 95% CI: 1.00-1.16), and those who used disposable paper cups (1.07; 95% CI: 1.01-1.13). PFOS was lower in underweight participants (0.84; 95%CI: 0.75-0.93) compared to those who were obese, and higher in those who exercised regularly (1.08; 95% CI: 1.03-1.14) or irregularly (1.06, 95% CI: 1.01-1.12) compared to those who did not exercise. Subjects who used severely damaged Teflon appliances had lower concentrations of PFOA (0.78, 95% CI: 0.65-0.95), while regular use of Gore-Tex goods was related to higher PFNA (1.15, 95% CI: 1.03-1.28) and PFDA (1.11; 95% CI: 1.02-1.20) levels. These findings suggest that most Koreans are frequently exposed to PFASs, and that serum concentrations of PFASs vary with age, sex, and exposure factors. [ABSTRACT FROM AUTHOR]

Tension energies for acyclic and cyclic assemblies of adamantane units sharing hexagons of carbon atoms converge in a size-extensive manner for large numbers n of adamantane units. In most cases the convergence features diagrams of strain energy per adamantane unit E (n-1) versus n-2 for cyclic aggregates and versus n-1 for acyclic aggregates having linear dependence with slopes of opposite signs. However, we found two exceptions which are discussed in the present paper, with convergence involving linear dependence with slopes of the same sign. [ABSTRACT FROM AUTHOR]

This review outlines the most recent papers describing the stereoselective synthesis of γ-amino acids. In this update, the γ-amino acids have been classified according to the type of compounds, position and number of substituents, and depending on the type of substrate, acyclic, carbocyclic or azacyclic derivatives, following in the first case an order related to the strategy used, whereas in the second and third cases the classification is based on the ring size. [ABSTRACT FROM AUTHOR]

As an increase in gastroesophageal reflux disease (GERD) has been reported in Japan, and public interest in GERD has been increasing, the Japanese Society of Gastroenterology published the Evidence-based Clinical Practice Guidelines for GERD (1st edition) in 2009. Six years have passed since its publication, and there have been a large number of reports in Japan concerning the epidemiology, pathophysiology, treatment, and Barrett's esophagus during this period. By incorporating the contents of these reports, the guidelines were completely revised, and a new edition was published in October 2015. The revised edition consists of eight items: epidemiology, pathophysiology, diagnosis, internal treatment, surgical treatment, esophagitis after surgery of the upper gastrointestinal tract, extraesophageal symptoms, and Barrett's esophagus. This paper summarizes these guidelines, particularly the parts related to the treatment for GERD. In the present revision, aggressive proton pump inhibitor (PPI) maintenance therapy is recommended for severe erosive GERD, and on-demand therapy or continuous maintenance therapy is recommended for mild erosive GERD or PPI-responsive non-erosive GERD. Moreover, PPI-resistant GERD (insufficient symptomatic improvement and/or esophageal mucosal break persisting despite the administration of PPI at a standard dose for 8 weeks) is defined, and a standard-dose PPI twice a day, change in PPI, change in the PPI timing of dosing, addition of a prokinetic drug, addition of rikkunshito (traditional Japanese herbal medicine), and addition of histamine H2-receptor antagonist are recommended for its treatment. If no improvement is observed even after these treatments, pathophysiological evaluation with esophageal impedance-pH monitoring or esophageal manometry at an expert facility for diseases of the esophagus is recommended. [ABSTRACT FROM AUTHOR]

Both IONCELL-P(ulp) and IONCELL-F(iber) are emerging new cellulose processing technologies utilizing ionic liquids (ILs). IONCELL-P is upgrading paper pulp into dissolving pulp with mixtures of IL and water. IONCELL-F is an IL based cellulose fiber spinning technology. In this work, these two processes were combined using the same ionic liquid, 1,5-diazabicyclo[4.3.0]non-5-ene acetate [DBNH][OAc], in both processes. In the IONCELL-P to achieve dissolving pulp quality cellulose (hemicellulose content below 5%) from birch kraft pulp, different pretreatments and optimization steps, such as targeted enzymatic predegradation of the xylans, preadjusting the viscosity of the pulp, and decreased pulp consistency (2%) in the fractionation, were implemented. From the obtained cellulose fraction containing 4.2% xylan, a dope was prepared from which high tenacity (50 cN/tex) and Young's modulus (23.6 GPa) fibers were spun with IONCELL-F dry jet wet spinning. The produced fibers surpassed the mechanical properties of commercially available viscose and Lyocell fibers. [ABSTRACT FROM AUTHOR]

1-Deoxynojirimycin (DNJ), the main hypoglycemic constituent in mulberry (Morus alba) latex, has been extensively researched. Although there is considerable interest in the biological effects of DNJ, the roles of 1-deoxynojirimycin (DNJ) in glycometabolism and energy metabolism in insects have received little attention. In this paper, 1H nuclear magnetic resonance (1H NMR) based metabonomic was performed to study the effects of the oral supplementation of 0.25% DNJ, 0.5% DNJ, latex, and the mixture of 0.5% DNJ and latex (1 : 1) on the fat body glycometabolism and energy metabolism of the fourth-instar larvae of Eri silkworms, Samia cynthia ricini. Metabolic pattern recognition analysis (partial least square-discriminant analysis, PLS-DA) of fat body extracts indicated that the groups of 0.25% DNJ, 0.5% DNJ, latex, and the mixture of 0.5% DNJ and latex (1 : 1) were significantly different from the control group. Further, compared to the control group, the metabolites levels of lactate, trehalose, succinate, malate, and fumarate were remarkably changed in experimental groups, which were involved in glycolysis, hydrolysis of trehalose, and tricarboxylic acid (TCA) cycle. Our results indicate that DNJ has a positive impact on the reverse energy metabolism of Eri silkworms and metabonomic analysis based on NMR can be used as a tool to identify potential biomarkers. [ABSTRACT FROM AUTHOR]

Furfural is one of the most valuable biomass-derived platform molecules which is primarily produced from hemicellulose. It is of significant importance but still highly challenging to produce furfural from hexoses, which are extensively distributed in nature. In this paper, carbohydrates (cellulose, starch, inulin, maltose, sucrose, glucose and fructose) were transformed into furfural efficiently over Hβ zeolite in a γ-butyrolactone–water solvent. The key process for converting hexoses into furfural is the selective cleavage of the C–C bond in hexoses to pentoses. The Hβ zeolite was discovered to induce the formation of acyclic hexoses, and the synergy between Hβ and solvent enables the selective C–C bond cleavage of acyclic hexoses into pentoses and promotes the subsequent dehydration of pentoses into furfural. Furfural yields for converting fructose and glucose reached 63.5% and 56.5% under milder conditions (150 °C), respectively. Moreover, a favorable yield of 38.5% for furfural can be achieved by direct conversion of cellulose. [ABSTRACT FROM AUTHOR]

Ytterbium (Yb), a widely used rare earth element, is treated as highly toxic to human being and adverseness to plant. Mitochondria play a significant role in plant growth and development, and are proposed as a potential target for ytterbium toxicity. In this paper, the biological effect of Yb(3+) on isolated rice mitochondria was investigated. We found that Yb(3+) with high concentrations (200 ~ 600 μM) not only induced mitochondrial membrane permeability transition (mtMPT), but also disturbed the mitochondrial ultrastructure. Moreover, Yb(3+) caused the respiratory chain damage, ROS formation, membrane potential decrease, and mitochondrial complex II activity reverse. The results above suggested that Yb(3+) with high concentrations could induce mitochondrial membrane dysfunction. These findings will support some valuable information to the safe application of Yb-based agents. [ABSTRACT FROM AUTHOR]

In this paper both the mechanistic and kinetic aspects of furfural formation from pentoses in aqueous acidic media have been reviewed. Based on the reviewed literature, a comprehensive reaction mechanism has been proposed consisting of more than one route, all starting from acyclic xylose, and involving alternately 1,2-enolization, β-elimination or isomerization via 1,2-hydride shift as key steps. Those studies that employ combined acid-base catalysts, soluble halide salts and trivalent cations in aqueous solutions appear to be most promising. Next, a detailed overview is presented of the results of kinetic studies on furfural formation from pentoses and furfural disappearance in aqueous acidic media. Although these results span over a very wide range of both experimental conditions and different kinetic models employed, an attempt has been made to present the published kinetic data in such a manner that it allows a global comparison. Since even in those cases where the reaction conditions seemed to be comparable, the reported kinetic constants often agree merely in the order of magnitude, thus, the validity of most of the data presented here is restricted to the specific conditions as used by each author. Additionally, a very concise overview is included of research on direct furfural production from lignocellulosic materials. In conclusion, the intricate set of reactions accompanying furfural formation from pentoses, although appearing well established in some aspects, is yet to be fully unraveled, especially with regard to the complex set of side and loss reactions seemingly involving largely unknown reaction intermediates. Such uncertainties are reflected in the contradictory kinetic models exploited and kinetic data presented in the literature, which still prevent a common and coherent interpretation. [ABSTRACT FROM AUTHOR]

Abstract: In alkaline pulping wood pulp is reacted with concentrated aqueous alkali at elevated temperatures. In addition to producing cellulose for the manufacture of paper, alkaline pulping also generates large amounts of isosaccharinic acids as waste products. Isosaccharinic acids are potentially useful raw materials: they are good metal chelating agents and, in their enantiomerically pure form, they are valuable carbon skeletons with predefined stereochemistry that can be easily functionalised for use in synthesis. Despite this, there is no simple procedure for isolating pure beta-(gluco)isosaccharinic acid and very limited work has been undertaken to determine the chemical and physical properties of this compound. We report here a very simple but effective method for the synthesis of a mixture containing equal portions of the two isosaccharinic acids ((2S,4S)-2,4,5-trihydroxy-2-(hydroxymethyl)pentanoic acid and (2R,4S)-2,4,5-trihydroxy-2-(hydroxymethyl)pentanoic acid) and the separation of the two as their tribenzoate esters. We also report for the first time the aqueous pK a of beta-(gluco)isosaccharinic acid (3.61). [Copyright &y& Elsevier]

Abstract: Mixed culture fermentation of Bacillus megaterium and Gluconobacter oxydans is widely used to produce 2-keto-l-gulonic acid (2-KGA), a key precursor for l-ascorbic acid synthesis. For such mixed cultivation, kinetic modelling is difficult because the interactions between the two strains are not well known yet. In this paper, data-driven prediction of the product formation is presented for the purpose of better process monitoring. A rolling learning-prediction approach based on neural networks is practiced to predict 2-KGA formation. Techniques associated with the approach, such as the data pretreatment and the rolling learning-prediction mechanism, are given in more detail. The validation results by using the data from commercial scale 2-KGA cultivation indicate that the prediction error is less than 5% in the later phase of fermentation and the reliable prediction time span is 8h. The robustness of the prediction approach is further tested by adding extra noises to the process variables. [Copyright &y& Elsevier]

Abstract: Process intensification (PI) has the potential to improve existing processes or create new process options, which are needed in order to produce products using more sustainable methods. In principle, an enormous number of process options can be generated but where and how the process should be intensified for the biggest improvement is difficult to identify. In this paper the development of a systematic computer aided model-based synthesis and design methodology incorporating PI is presented. In order to manage the complexities involved, the methodology employs a decomposition-based solution approach. Starting from an analysis of existing processes, the methodology generates a set of process options and reduces their number through several screening steps until from the remaining options, the optimal is found. The application of the methodology is highlighted through a case study involving the chemo-enzymatic synthesis of N-acetyl-d-neuraminic acid (Neu5Ac). [Copyright &y& Elsevier]

Abstract: Recently, we reported a new mutation of phosphoglycerate kinase (PGK), called PGK-Barcelona, which causes chronic hemolytic anemia associated with progressive neurological impairment. We found a 140T→A substitution that produces an Ile46Asn change located at the N-domain of the enzyme and we suggested that the decrease of the PGK activity is probably related to a loss of enzyme stability. In this paper, by analyzing whole hemolysates and cloned enzymes, we show that both enzymes possess similar kinetic properties (although some differences are observed in the Km values) and the same electrophoretic mobility. However, PGK-Barcelona has higher thermal instability. Therefore, we confirm that the decrease of the red blood cell (RBC) PGK activity caused by the PGK-Barcelona mutation is more closely related to a loss of enzyme stability than to a decrease of enzyme catalytic function. Furthermore, we have measured the levels of glycolytic metabolites and adenine nucleotides in the RBC from controls and from the patient. The increase of 2,3-bisphosphoglycerate and the decrease of ATP RBC levels are the only detected metabolic changes that could cause hemolytic anemia. [Copyright &y& Elsevier]

In this paper we apply a recursive neural network (RNN) model to the prediction of the standard Gibbs energy of solvation in water of mono- and polyfunctional organic compounds. The proposed model is able to directly take as input a structured representation of the molecule and to model a direct and adaptive relationship between the molecular structure and the target property. A data set of 339 mono- and polyfunctional acyclic compounds including alkanes, alkenes, alkynes, alcohols, ethers, thiols, thioethers, aldehydes, ketones, carboxylic acids, esters, amines, amides, haloalkanes, nitriles, and nitroalkanes was considered. As a result of the statistical analysis, we obtained for the predictive capability estimated on a test set of molecules a mean absolute residual of about 1 kJ·mol−1and a standard deviation of 1.8 kJ·mol−1. This results is quite satisfactory by considering the intrinsic difficulty of predicting solvation properties in water of compounds containing more than one functional group. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the influence of Bis-EMA 30 on the resin-to-dentin microtensile bond strength (microTBS) and structural reliability of the experimental three-step etch-and-rinse adhesive systems.Methods: Five experimental primers containing different dimethacrylate monomer concentrations (0, 10, 20, 40, 60 wt% of the Bis-EMA 30, P0.P60) added to acid monomer and solvents (ethanol/water), and a resin bond (Bis-GMA/TEGDMA, 50/50 wt%) were formulated. The adhesive system Scotchbond MultiPurpose (SBMP, 3M ESPE) was tested as commercial reference. Sixty bovine incisors were randomly separated into six groups, and their superficial coronal dentin was exposed. After acid etching and rinsing, the excess water was removed from the surface with absorbent paper. Each experimental primer was actively applied (30 s), followed by a mild air stream (10 s). The experimental adhesive resin was applied and light activated for 20 s. Resin composite restorations were incrementally built up. The restored teeth were stored in distilled water at 37 degrees C for 24 h, and then sectioned to obtain sticks with a cross-sectional area of approximately 0.5 mm(2), after which 24 specimens per group were subjected to the microTBS test. Data (MPa) were analyzed by One-way ANOVA, Tukey test (alpha=0.05) and Weibull analysis.Results: The P40 group showed microTBS means similar to those of the control (SBMP), whereas both had statistically higher values when compared with the other groups (p<0.001). Moreover, P40 showed higher structural reliability, represented by the high Weibull modulus and characteristic strength values. The lowest microTBS was observed in the P0, P10 and P20 groups, which also had low structural reliability.Significance: Bis-EMA 30 is a promising monomer to be considered as a substitute for HEMA in adhesive system compositions. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To evaluate the quality of bonded resin–dentine interfaces produced by two self-etching primer adhesives after casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) treatment, in comparison to untreated dentine. Methods: Thirty-four adult molar teeth were sectioned to obtain dentine with tubule orientations parallel/oblique or perpendicular to the surface. The specimens were divided into ‘smear layer’ (1A, 1B) and ‘no smear layer’ groups, after treatment with 15% EDTA (2A, 2B). The specimens were then left either untreated (1A, 2A) or treated (1B, 2B) with CPP–ACP paste (Tooth Mousse, GC Corp.) for 60min×7 days. Each treatment group was divided into three subgroups and specimens etched/conditioned (no conditioning; 30–40% phosphoric acid (H3PO4); 20% polyacrylic acid) and bonded with either a 2-step self-etching primer adhesive (Clearfil SE Bond, Kuraray Medical) or an ‘all-in-one’ adhesive (G-Bond, GC Corp.) and a hybrid resin composite. After 24-h water storage, the bonded specimens were sectioned, polished up to 4000-grit abrasive silicon carbide paper and 0.25-μm diamond paste, prepared for FE-SEM using the acid–base technique, critical point-dried, gold-coated and examined. Bonded and fractured dentine interfaces were also prepared and examined. Results: The 2-step adhesive produced a similar appearance of bonded resin–dentine interface irrespective of smear layer group, treatment or etching/conditioning. After polyacrylic acid conditioning, the ‘all-in-one’ adhesive exhibited more areas with bond failures. The bond failures were within the hybrid layer and more pronounced following CPP–ACP treatment. Conclusion: The quality of the bonded resin–dentine interface produced after CPP–ACP treatment may depend on the adhesive system used. [Copyright &y& Elsevier]

Objectives: The provision of antiplaque benefits to dentifrices assists patients in improving hygiene and reducing susceptibility to gingivitis and caries. Chemical plaque control involves different mechanisms and is mostly associated with antibacterial effects, but also includes effects on pellicle surface chemistry to improve cleansing or discourage renewed plaque formation. It is the aim of this paper to analyze in vitro detachment of co-aggregating oral actinomyces and streptococci from pellicle surfaces by dentifrice supernates and to study subsequent de novo streptococcal deposition.Methods: Detachment by dentifrices of a co-adhering bacterial pair was studied in the parallel plate flow chamber on a 16 h pellicle coated surface. After detachment by perfusing the chamber with a dentifrice, re-deposition was initiated by flowing with a fresh streptococcal suspension. The dentifrices included both a regular, SLS-fluoride based formulation as well a pyrophosphate, anticalculus and antimicrobial formulations.Results: All dentifrice supernates containing SLS were effective in detaching co-adhering bacteria from pellicles surfaces, except in combination with SnF(2). When hexametaphosphate was added immediate detachment was relatively low, but continued even during re-deposition. The re-deposition of streptococci after detachment by other, NaF containing dentifrices involved relatively few large aggregates, presumably because fluoride was able to block bi-dentate calcium binding sites on the bacterial cell surfaces, mediating co-adhesion. When pyrophosphate was present in addition to NaF, re-deposition involved significantly more large aggregates, likely because pyrophosphate served as a bi-dentate bridge between calcium bound on the bacterial cell surfaces.Conclusion: Commercially available dentifrice formulations differ in their ability to stimulate bacterial detachment from pellicles and dependent on their composition yield the formation of large co-adhering aggregates of actinomyces and streptococci in de novo deposition. [ABSTRACT FROM AUTHOR]