bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibiofilm and Antimicrobial Activity of Polyethylenimine: An Interesting Compound for Endodontic Treatment
Authors: Pina-Vaz Irene , Barros Joana , Dias Ana , Rodrigues Miguel A , Pina-Vaz Cidália , Lopes Maria A 
Published: October 2015

ABSTRACT

Aim
Bacteria levels of necrotic teeth are greatly reduced after endodontic treatment procedures but the presence of persisting microorganisms leads to continuous efforts to develop materials with antimicrobial properties. The purpose of the study was to determine the antimicrobial activity of polyethylenimine (PEI) against common bacteria and yeasts, regarding planktonic cells and biofilm, and to clarify its antimicrobial mechanism of action through flow cytometry.

Materials and methods
The antibiofilm and antimicrobial effect of PEI was determined against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Candida albicans strains using reference protocols. The effect of PEI was evaluated regarding adhesion, biofilm formation and biofilm disaggregation. In order to understand PEI cellular effects flow cytometric analysis was performed with different fluorescent markers.

Results
It was verified that minimal inhibitory concentrations (MIC) values and minimal lethal concentrations (MLC) obtained for PEI were similar and ranged between 50 and 400 mg/l, proving the microbicidal and fungicidal activity of this compound. Antibiofilm activity was also proved for all the microorganisms. Severe lesion of the membrane and cell depolarization was demonstrated.

Conclusion
Polyethylenimine showed antimicrobial and antibiofilm activity against microorganisms often associated with apical periodontitis.

Clinical significance
Theoretically, prolonging the antibacterial effects of materials used in endodontics may be interesting to help prevent reinfection and possibly to affect residual bacteria that survived the treatment procedures.

How to cite this article
Barros J, Dias A, Rodrigues MA, Pina-Vaz C, Lopes MA, Pina-Vaz I. Antibiofilm and Antimicrobial Activity of Polyethylenimine: An Interesting Compound for Endodontic Treatment. J Contemp Dent Pract 2015;16(6):427-432.
Effectiveness of a Chlorhexidine Digluconate 0.12% and Cetylpyridinium Chloride 0.05% Solution in eliminating Candida albicans Colonizing Dentures: A Randomized Clinical in vivo Study
Authors: Cassia Antoine 
Published: October 2015

ABSTRACTBackgroundEffective denture hygiene is important for patients suffering from denture stomatitis (DS). This study aimed to evaluate the efficacy of a solution containing 0.12% chlorhexidine (CHX) digluconate and 0.05% cetylpyridinium chloride (CPC) in eliminatingCandida albicanscolonizing dentures.Materials and methodsForty denture wearers (11 men, 29 women; age range 40 to 80 years) with clinical evidence of DS were randomly divided into two groups, one test and one control. The dentures of the test group were treated by immersion in a solution of 0.12% CHX and 0.05% CPC while those of the control group were immersed in distilled water. Swabs were collected from the fitting surfaces of the upper dentures prior and post cleaner use and examined mycologically.ResultsReduction in the number of colony-forming units (CFU) ofCandida albicansafter immersion of the dentures in a solution of 0.12% CHX and 0.05% CPC was significantly greater than that of the control group.ConclusionA solution of 0.12% CHX and 0.05% CPC tested as a product of disinfection of the acrylic dentures showed significant results after immersion of 8 night hours for 4 days.How to cite this articleAoun G, Cassia A, Berberi A. Effectiveness of a Chlorhexidine Digluconate 0.12% and Cetylpyridinium Chloride 0.05% Solution in eliminatingCandida albicansColonizing Dentures: A Randomized Clinicalin vivoStudy. J Contemp Dent Pract 2015;16(6):433-436.
Determination of Root Canal Cleanliness by Different Irrigation Methods and Morphometric Analysis of Apical Third
Authors: Estrela Carlos , Seixas Fábio Heredia , Bueno Mike Reis , Sousa-Neto Manoel Damião , Pécora Jesus Djalma 
Published: October 2015

ABSTRACT

Aim
The aim of this study was to determine the root canal area before and after the instrumentation 1 mm short of the apical foramen by clinical and cone beam computed tomography (CBCT) methods, and to evaluate the cleanliness of the apical region in mesiodistal flattened teeth by using optical microscopy.

Materials and methods
Forty-two human single-canal mandibular incisors were instrumented using the Free Tip Preparation technique up to three, four or five instruments from the initial. Cone beam computed tomography scans were acquired of the samples before and after root canal preparation (RCP). Irrigation was performed by conventional or hydrodynamic means, using 2.5% sodium hypochlorite. The samples were prepared for observation under an optical microscope. Images were digitally obtained, analyzed and the results were submitted to statistical analysis (two-way ANOVA complemented by Bonferroni's post-test).

Results
There was no significant difference between the studied anatomical areas with both CBCT and clinical methods. There were no differences between irrigation methods. It was verified differences between instrumentation techniques. Instrumentation with four instruments from the initial instrument determined a significant increase in the contact area when compared to preparation with three instruments, but RCP with 5 instruments did not result in a better cleanliness.

Conclusion
The analysis with CBCT was not capable to determine the precise shape of surgical apical area comparing to the clinical method.

Clinical significance
Both the conventional and hydrodynamic irrigation techniques were not able to promote root canals debris-free. The instruments action in root canal walls was proportional to the number of instruments used from the initial apical instrument.

How to cite this article
Seixas FH, Estrela C, Bueno MR, Sousa-Neto MD, Pécora JD. Determination of Root Canal Cleanliness by Different Irrigation Methods and Morphometric Analysis of Apical Third. J Contemp Dent Pract 2015;16(6):442-450.
Calcium Hydroxide Dressing Influences the Obturation of Simulated Lateral Canals
Authors: Jorge Karin Milena , de Carvalho Roberta Ferreira , Vieira Verena Luzia Bredt , Gabardo Marilisa Carneiro Leão , Gonçalves Letícia Machado , Deonizio Marili Doro Andrade 
Published: October 2015

ABSTRACTAimThe aim of this study was to investigate the influence of calcium hydroxide dressing on the filling of simulated lateral canals by different obturation techniques.Materials and methodsSixty single-root-premolars were instrumented. Simulated lateral canals were drilled on each third of the roots. The teeth were divided into four groups: no dressing and obturation by lateral condensation technique (G1), dressing with calcium hydroxide and obturation by lateral condensation technique (G2), no dressing and obturation by hybrid technique (G3) and, dressing with calcium hydroxide and obturation by hybrid technique (G4). The teeth were maintained at 37°C in 100% humidity for 7 days, and obturation techniques were performed. Radiographs were taken and filled or unfilled lateral canals were counted. Data were analyzed using analysis of variance (ANOVA) followed by Tukey's test (α = 5%).ResultsThe hybrid technique filled large number of lateral canals as compared to lateral condensation technique, regardless the use of intracanal medication (p < 0.05). Calcium hydroxide decreased the number of lateral canals filled for both lateral and hybrid techniques (p < 0.05). Significant differences were observed when comparing the number of filled and unfilled lateral canals in the same root third of each group (p < 0.05).ConclusionRegardless the obturation technique, calcium hydroxide dressing reduced the penetration of filling material in simulated lateral canals.Clinical significanceThe persistence of calcium hydroxide residues reduces the penetration of filling material in simulated lateral canals, possibly representing a potential cause of failure in the future.How to cite this articleJorge KM, de Carvalho RF, Vieira VLB, Gabardo MCL, Gonçalves LM, Deonizio MDA. Calcium hydroxide Dressing Influences the Obturation of Simulated Lateral Canals. J Contemp Dent Pract 2015;16(6):468-473.
A Study on Duration of Effect of Transcutaneous Electrical Nerve Stimulation Therapy on Whole Saliva Flow
Authors: Bhasin Neha , Reddy Sreedevi , Nagarajappa Anil Kumar , Kakkad Ankur 
Published: October 2015

ABSTRACT

Background
Saliva is a complex fluid, whose important role is to maintain the well being of oral cavity. Salivary gland hypofunction or hyposalivation is the condition of having reduced saliva production which leads to the subjective complaint of oral dryness termed xerostomia.7 Management of xerostomia includes palliative therapy using topical agents or systemic therapy. Electrostimulation to produce saliva was studied in the past and showed moderate promise but never became part of mainstream therapy. Hence, this study was undertaken to evaluate the effect of transcutaneous electrical nerve stimulation (TENS) on whole salivary flow rate in healthy adults and to evaluate how long this effect of TENS lasts on salivary flow.

Materials and methods
One hundred healthy adult subjects were divided into five age groups with each group containing 20 subjects equally divided into males and females in each group. Unstimulated saliva was collected using a graduated test tube fitted with funnel and quantity was measured. Transcutaneous electrical nerve stimulation unit was activated and stimulated saliva was collected. Saliva was again collected 30 minutes and 24 hours post stimulation.

Results
The mean unstimulated whole saliva flow rate for all subjects (n = 100) was 2.60 ml/5 min. During stimulation, it increased to 3.60 ± 0.39 ml/5 min. There was 38.46% increase in salivary flow. Ninety six out of 100 responded positively to TENS therapy. Salivary flow remained increased 30 minutes and 24 hours post stimulation with the values being 3.23 ± 0.41 ml/5 min and 2.69 ± 0.39 ml/5 min respectively. Repeated measures One way analysis of variance (ANOVA) test showed that the difference between these values were statistically significant.

Conclusion
Transcutaneous electrical nerve stimulation therapy was effective for stimulation of whole saliva in normal, healthy subjects and its effect retained till 30 minutes and a little up to 24 hours. Transcutaneous electrical nerve stimulation may work best synergistically with other sialagogues and can be used for the management of xerostomia.

How to cite this article
Bhasin N, Reddy S, Nagarajappa AK, Kakkad A. A Study on Duration of Effect of Transcutaneous Electrical Nerve Stimulation Therapy on Whole Saliva Flow. J Contemp Dent Pract 2015;16(6):479-485.
De Nederlandse wetgever en andere normenstelsels: op zoek naar het recht der werkelijkheid
Authors: Smits Jan 
Published: October 2015

The Dutch legislator and other normative systems
It is well known that the role of the national legislator in setting legally relevant norms is rapidly changing under the influence of increasing Europeanization, globalization and privatization. Today the national legislator is only one of the relevant norm-setters. This contribution considers the role that the Dutch legislator sees for itself in this emerging multilevel legal order. To this end, six themes of fundamental importance in a multilevel order are explored: (1) the question of when government regulation is to be preferred over private regulation; (2) the question of at which level of government (national, European, sub-national or supranational) a topic is preferably dealt with; (3) the role of the national legislator in realizing the cognoscibility and coherence of law; (4) the preferred way of implementing EU directives; (5) the question of whether the national legislator must refer to codes of conduct, certification and norms of standards bodies, and if so how; (6) the question of whether the national legislator must position its own national law on the international ‘law market.’
Influence of explicit Phaeocystis parameterizations on the global distribution of marine dimethyl sulfide
Authors: Wang Shanlin , Elliott Scott , Maltrud Mathew , Cameron‐Smith Philip 
Published: October 2015

AbstractDimethyl sulfide (DMS) is a biogenic organosulfur compound which contributes strongly to marine aerosol mass and the determination of cloud condensation nuclei over the remote oceans. Since uncertainties in DMS flux to the atmosphere lead to large variations in climate forcing, the global DMS distribution has been the subject of increasingly complex dynamic simulations. DMS concentrations are directly controlled by marine ecosystems. Phaeocystis is a major DMS producer but is often omitted from global reduced sulfur mechanisms. Here we incorporate this phytoplankton group into the marine ecosystem‐biogeochemical module of the Community Earth System Model. To examine its role in the ocean sulfur cycle, an earlier DMS model has been enhanced to include new knowledge gained over the last few years. Results from the baseline run show that simulated Phaeocystis biomass generally agrees with observations, with high concentrations near the Antarctic continent and between 50° and 60° north. Given the new explicit Phaeocystis representation, the DMS distribution shows significant improvements, especially regarding the amplitude and location of high‐latitude peaks. The simulated global mean surface DMS value is 2.26 nM, comparable to an estimate of 2.34 nM from the latest climatology extrapolated based on observations. The total oceanic DMS source to the atmosphere is 20.4 Tg S/yr, on the low side of previous estimates. Comparisons with and without Phaeocystis show that the group dominates DMS distributions in temperate and cold waters, contributing 13% of the global flux. The proportion may increase as sea ice declines and should be considered in climate projections.
Allergic rhinitis and associated risk of migraine among children: a nationwide population‐based cohort study
Authors: Wang I‐Chung , Tsai Jeng‐Dau , Lin Cheng‐Li , Shen Te‐Chun , Li Tsai‐Chung , Wei Chang‐Ching 
Published: October 2015

BackgroundIncreased frequency of migraine was reported in adults with allergic rhinitis (AR). Although migraine is less common in children than in adults, it can begin in early childhood and persist into adulthood. We conducted this population‐based cohort study to investigate the incidence and subsequent risk of migraine in children with AR.MethodsFrom 2000 to 2007, 461,850 children with recently diagnosed AR and 460,718 non‐AR controls were included in the study. By the end of 2008, incidences of migraine in both cohorts, the AR to non‐AR cohort hazard ratios (HRs), and confidence intervals (CIs) were measured.ResultsThe incidence of migraine during the study period was 3.2‐fold higher in the AR cohort (95% CI, 2.97 to 3.46) than in the non‐AR cohort (11.4 vs 3.49 per 10000 person‐years). The risk was greater for boys than for girls, and for children aged <6 years. The HR for migraine in children with AR was 1.44 (95% CI, 1.31 to 1.58) for those with ≤2 annual AR‐related medical visits, whereas, 14.8 (95% CI, 13.6 to 16.2) for those with >4 visits (p < 0.0001, the trend test). The risk of migraine development in the AR cohort was highest within the first year after AR diagnosis (HR 4.89; 95% CI, 3.98 to 6.00). Children with AR were more likely to have migraine without aura than migraine with aura.ConclusionChildren with AR had a higher incidence and subsequent risk of migraine. Physicians should be more aware of migraine in children with AR who complain of headache.
Charge Tunneling along Short Oligoglycine Chains
Authors: Baghbanzadeh Mostafa , Bowers Carleen M. , Rappoport Dmitrij , Żaba Tomasz , Gonidec Mathieu , Al‐Sayah Mohammad H. , Cyganik Piotr , Aspuru‐Guzik Alan , Whitesides George M. 
Published: October 2015

AbstractThis work examines charge transport (CT) through self‐assembled monolayers (SAMs) of oligoglycines having an N‐terminal cysteine group that anchors the molecule to a gold substrate, and demonstrate that CT is rapid (relative to SAMs of n‐alkanethiolates). Comparisons of rates of charge transport‐using junctions with the structure AuTS/SAM//Ga2O3/EGaIn (across these SAMs of oligoglycines, and across SAMs of a number of structurally and electronically related molecules) established that rates of charge tunneling along SAMs of oligoglycines are comparable to that along SAMs of oligophenyl groups (of comparable length). The mechanism of tunneling in oligoglycines is compatible with superexchange, and involves interactions among high‐energy occupied orbitals in multiple, consecutive amide bonds, which may by separated by one to three methylene groups. This mechanistic conclusion is supported by density functional theory (DFT).
Circularly Polarized Luminescence of Chiral Pt(pppb)Cl (pppbH=1‐pyridyl‐3‐(4,5‐pinenopyridyl)benzene) Aggregate in the Excited State
Authors: Tanaka Saori , Sato Kyohei , Ichida Kyoko , Abe Taichi , Tsubomura Taro , Suzuki Takayoshi , Shinozaki Kazuteru 
Published: October 2015

AbstractWe prepared enantiomers of chiral PtII complexes, Pt(pppb)Cl and Pt(pppb)CN (pppbH=1‐pyridyl‐3‐(4,5‐pinenopyridyl)benzene), and measured their CPL (circularly polarized luminescence) spectra for excimer and trimer emission. The contribution of the pinene moiety to CPL was considerably low for the π–π* emission of the monomer but large for MMLCT (metal‐metal‐to‐ligand charge‐transfer) of the excimer and trimer which had a helical structure induced in a face‐to‐face stacking fashion. The trimer CPL for (+)‐Pt(pppb)Cl was larger in intensity than that of excimer CPL; on the other hand, that for (+)‐Pt(pppb)CN was opposite in sign compared with that of excimer CPL. We conclude that differences in the excited‐state structure of the aggregate between Pt(pppb)Cl and Pt(pppb)CN account for the variation in the CPL spectra. By the aid of TD‐DFT calculations it was predicted that the dihedral angle θ(Cl‐Pt‐Pt‐Cl) was 50–60° or 110–140° for Pt(pppb)Cl aggregates and 160° for Pt(pppb)CN aggregates.
Convenient Reductive Methylation of Amines with Carbonates at Room Temperature
Authors: Li Yuehui , Sorribes Iván , Vicent Cristian , Junge Kathrin , Beller Matthias 
Published: October 2015

AbstractMethylation of amines is a fundamental and commonly used reaction in organic synthesis. Many methods are known including various reductive methylations using formaldehyde, formic acid, or carbon dioxide in the presence of reductants. However, several of these methods suffer from limited substrate scope and chemoselectivity because of the different nucleophilicities of substrates. In this respect, the combination of carbonates and hydrosilanes is a valuable methylation source in the presence of Pt‐based catalysts. This highly tunable method allows for methylation of both aromatic and aliphatic amines, and chemoselective methylation of aminoalcohols and diamines. Notably, the in situ‐formed catalyst can also be used for the reduction of carbonates to methanol at room temperature. Mechanistic insights on intermediates formed during the reaction pathway were obtained by using ESI mass spectrometry.
Redox Active Compounds in Controlled Radical Polymerization and Dye‐Sensitized Solar Cells: Mutual Solutions to Disparate Problems
Authors: Ballard Nicholas , Mecerreyes David , Asua José M. 
Published: October 2015

AbstractControlled radical polymerization (CRP) and dye‐sensitized solar cells (DSSCs) are two fields of research that at an initial glance appear to have little in common. However, despite their obvious differences, both in application and in scientific nature, a closer look reveals a striking similarity between many of the compounds widely used as control agents in radical polymerization and as redox couples in dye‐sensitized solar cells. Herein, we review the various redox active compounds used and examine the characteristics that give them the ability to perform this dual function. In addition we explore the advances in the understanding of the structural features that enhance their activity in both CRP and DSSCs. It is hoped that such a comparison will be conducive to improving process performance in both fields.
Chiral N,N′‐Dioxide–Scandium(III)‐Catalyzed Asymmetric Dearomatization of 2‐Naphthols through an Amination Reaction
Authors: Lian Xiangjin , Lin Lili , Wang Guojin , Liu Xiaohua , Feng Xiaoming 
Published: October 2015

AbstractA catalytic asymmetric dearomatization of 2‐naphthols with azodicarboxylates has been accomplished by using a N,N′‐dioxide‐scandium(III) complex as a chiral catalyst. A number of optically active β‐naphthalenone compounds with a nitrogen‐containing quaternary carbon stereocenter were obtained in up to 99 % yield and up to 99 % ee under mild reaction conditions. The reaction could be scaled up to a gram‐scale with the yield and ee maintained. Based on these experiments and on previous reports, a possible transition state was proposed.
Construction of Bridged Polycyclic Systems by Polyene Cyclization
Authors: Suzuki Keisuke , Yamakoshi Hiroyuki , Nakamura Seiichi 
Published: October 2015

AbstractA stereoselective construction of bridged tri‐ and tetracyclic systems embedded in some 3,5‐dimethylorsellinic acid (DMOA)‐derived meroterpenoids was achieved by exploiting a polyene cyclization of suitably functionalized epoxyallylsilanes. Both the olefinic substituent on the epoxide and allylic trimethylsilyl (TMS) group were found to play pivotal roles in the success of the present reaction. The fact that the cyclization of monocyclized byproducts did not proceed strongly suggests that the reaction could be a concerted transformation.