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Introduction: This study investigated the distribution pattern of tenascin‐C and syndecan‐1 in the dental mesenchyme during root development of immature swine teeth in order to define the differentiation dynamics of both pulp tissue progenitors and apical papilla cells, as well as to assess the adequacy criticize of the apical papilla to induce dentin–pulp regeneration. Methods: Three 7‐month‐old miniature swine were used in this study. A total of 12 teeth, including two immature permanent incisors and two premolar teeth of each case, were extracted and processed for histological and immunohistochemical analysis. Different populations of mesenchymal cells located at the root apex were morphologically evaluated in hematoxylin–eosin serial sections. Additionally, the distribution patterns of tenascin‐C and syndecan‐1 were assessed immunohistochemically. Results: Syndecan‐1 was strongly expressed in the dental pulp, particularly along the odontoblasts of the root and the newly deposited predentin layer. Tenascin‐C was intensely expressed in the dental pulp. The apical papilla and dental follicle showed no expression of either molecule. Conclusions: Cell differentiation potential in the developing swine apex is progressively restricted to the newly formed dental pulp, whereas phenotypic expression of apical papilla cells remains undetermined unless the new microenvironment triggers cell differentiation towards the odontoblastic lineage. [ABSTRACT FROM AUTHOR]

Over the past two decades, with recognition that the ocean's sea-ice cover is neither insensitive to climate change nor a barrier to light and matter, research in sea-ice biogeochemistry has accelerated significantly, bringing together a multi-disciplinary community from a variety of fields. This disciplinary diversity has contributed a wide range of methodological techniques and approaches to sea-ice studies, complicating comparisons of the results and the development of conceptual and numerical models to describe the important biogeochemical processes occurring in sea ice. Almost all chemical elements, compounds, and biogeochemical processes relevant to Earth system science are measured in sea ice, with published methods available for determiningbiomass, pigments, net community production, primary production, bacterial activity, macronutrients, numerous natural and anthropogenic organic compounds, trace elements, reactive and inert gases, sulfur species, the carbon dioxide system parameters, stable isotopes, and water-ice-Atmosphere fluxes of gases, liquids, and solids. For most of these measurements, multiple sampling and processing techniques are available, but to date there has been little intercomparison or intercalibration between methods. In addition, researchers collect different types of ancillary data and document their samples differently, further confounding comparisons between studies. These problems are compounded by the heterogeneity of sea ice, in which even adjacent cores can have dramatically different biogeochemical compositions. We recommend that, in future investigations, researchers design their programs based on nested sampling patterns, collect a core suite of ancillary measurements, and employ a standard approach for sample identification and documentation. In addition, intercalibration exercises are most critically needed for measurements of biomass, primary production, nutrients, dissolved and particulate organic matter (including exopolymers), the CO2 system, air-ice gas fluxes, and aerosol production. We also encourage the development of in situ probes robust enough for long-Term deployment in sea ice, particularly for biological parameters, the CO2 system, and other gases.

Research evidence from several educational systems indicates that students with developmental disabilities who exhibit challenging behaviors are in the bottom of the agenda as candidates for inclusion. The present investigation of the perspectives of 85 Greek teachers in primary education indicates that they are in need of training that it will enable them to deal with the presence of a student with challenging behaviors in their classroom and that it will assist them to overcome their concerns about the impact of inclusion of students with challenging behaviors on their time and emotional well-being, the routine of the class, the peer acceptance and the educational progress of the student with challenging behaviors. The implications for training are briefly discussed.

Vassilios Karavelidis1,2, Evangelos Karavas2, Dimitrios Giliopoulos1, Sofia Papadimitriou1, Dimitrios Bikiaris11Laboratory of Polymer Chemistry and Technology, Chemistry Department, Aristotle University of Thessaloniki, Thessaloniki, 2Pharmathen SA, Pharmaceutical Industry, Pallini Attikis, Attiki, GreeceAbstract: Four new polyesters based on 1,3-propanediol and different aliphatic dicarboxylic acids were used to prepare ropinirole HCl-loaded nanoparticles. The novelty of this study lies in the use of polyesters with similar melting points but different degrees of crystallinity, varying from 29.8% to 67.5%, as drug nanocarriers. Based on their toxicity to human umbilical vein endothelial cells, these aliphatic polyesters were found to have cytotoxicity similar to that of polylactic acid and so may be considered as prominent drug nanocarriers. Drug encapsulation in polyesters was performed via an emulsification/solvent evaporation method. The mean particle size of drug-loaded nanoparticles was 164–228 nm, and the drug loading content was 16%–23%. Wide angle X-ray diffraction patterns showed that ropinirole HCl existed in an amorphous state within the nanoparticle polymer matrices. Drug release diagrams revealed a burst effect for ropinirole HCl in the first 6 hours, probably due to release of drug located on the nanoparticle surface, followed by slower release. The degree of crystallinity of the host polymer matrix seemed to be an important parameter, because higher drug release rates were observed in polyesters with a low degree of crystallinity.Keywords: biocompatible polyesters, nanoparticles, ropinirole, release, crystallinity

Megafaunal burrows were detected in boxcores from the two cites in the bathyal north-east Atlantic, which was analysed to asses the significance to sediment radiotracer profiles and organic composition. The result showed that (super 210)Pb(sub excess) and organic content indicated a phytodetrital origin, and extended linear bands of faecal pellets were present in three boxcars at 13-17 cm dept. The results suggest that 'catching' of phytodetritus and subsurface deposition of faeces are two mechanisms for the rapid, deep burial of relatively fresh organic matter.

Aim: To investigate pulp responses after pulpotomy and EDTA conditioning of pulp chamber dentinal walls with or without the placement of a collagenous scaffold in the experimental model of miniature swine teeth. Methodology: Forty‐two fully developed permanent premolars and molars of healthy miniature swines were used. After preparation of pulp exposures through Class I cavities, the tissue of the pulp chamber was completely removed. The haemorrhage was controlled, and the root pulp was protected using a polyurethane film. The circumpulpal pulp chamber dentine was treated for 3 min with normal saline (group 1), or 17% EDTA solution (groups 2 and 3). The film was removed, and the pulp chamber cavities were left empty (groups 1 and 2), or filled with swine collagenous sponge (group 3). The access cavities were restored with a Teflon disc and glass ionomer. Teeth were evaluated histo‐morphologically after 10 weeks. Data were compared using the nonparametric Fisher's exact test. Results: Teeth after treatment of dentine with saline (group 1) were associated with no or only traces of hard tissue formation along the root canal walls. Atubular tertiary dentine deposition in the form of matrix deposition along root canal walls, or dentine bridge formation at the orifice of root canals or complete pulp canal obliteration, was found after treatment of dentine with EDTA in both experiments (groups 2 and 3). Significantly different types of mineralization in the root canals of groups 2 and 3 were seen (P = 0.001). Tissue changes in the pulp cavity, characterized by soft tissue growth and osteodentine or atubular tertiary dentine formation, were only seen after EDTA conditioning of dentine, in 6.2% of the teeth without scaffold and 64.7% of the teeth with scaffold application. Newly deposited mineralized matrix in the pulp chamber was always in continuation with hard tissue deposited in the root canals. Conclusions: The EDTA conditioning of pulp cavity dentinal walls after pulpotomy induced dentinogenic events in the root pulp. Application of collagenous scaffold in the pulp chamber enhanced soft tissue growth and mineralized tissue formation along the treated circumpulpal dentine. [ABSTRACT FROM AUTHOR]