Histone Methylation Marks on Circulating Nucleosomes as Novel Blood-Based Biomarker in Colorectal Cancer

Circulating nucleic acids (CNAs) are under investigation as a liquid biopsy in cancer as potential non-invasive biomarkers, as stable structure in circulation nucleosomes could be valuable sources for detection of cancer-specific alterations in histone modifications. Our interest is in histone methylation marks with a focus on colorectal cancer, one of the leading cancers respective the incidence and mortality. Our previous work included the analysis of trimethylations of lysine 9 on histone 3 (H3K9me3) and of lysine 20 on histone 4 (H4K20me3) by chromatin immuno- precipitation-related PCR in circulating nucleosomes. Here we asked whether global immunologic measurement of histone marks in circulation could be a suitable approach to show their potential as biomarkers. In addition to H3K9me3 and H4K20me3 we also measured H3K27me3 in plasma samples from CRC patients (n = 63) and cancer free individuals (n = 40) by ELISA-based methylation assays. Our results show that of three marks, the amounts of H3K27me3 (p = 0.04) and H4K20me3 (p < 0.001) were significantly lower in CRC patients than in healthy controls. For H3K9me3 similar amounts were measured in both groups. Areas under the curve (AUC) in receiver operating characteristic (ROC) curves indicating the power of CRC detection were 0.620 for H3K27me3, 0.715 for H4K20me3 and 0.769 for the combination of both markers. In conclusion, findings of this preliminary study reveal the potential of blood-based detection of CRC by quantification of histone methylation marks and the additive effect of the marker combination.     

Varnish layer hardness of oriental beech (fagus orientalist L.) wood as affected by impregnation and bleaching

The impacts of impregnation and bleaching on the varnish layer hardness of Oriental beech (Fagus orientalist L.) wood were investigated. A number of bleaching combinations {[NaOH−H₂O₂], [NaOH−Ca(OH)₂−H₂O₂], [NaOH−MgSO₄−H₂O₂] [NaHSO₃−H₂C₂O₄], [NaSiO₃−H₂O₂], [KMnO₄+NaHSO₃+H₂O₃]} were applied at 18% concentration for bleaching to both impregnated and unimpregnated specimens of Oriental beech wood. Subsequently, water-based (WB) varnish was coated over the samples and the varnish layer hardness values were determined in accordance with ASTM D 4366-95. All of the chemicals used for bleaching reduced the surface hardness. However, after varnish coating, the hardness of most samples was similar to that of the varnish-coated natural (control) samples.     

Surface analysis and adsorption behavior of caffeine as an environmentally friendly corrosion inhibitor at the copper/aqueous chloride solution interface

Abstract

Corrosion inhibitors based on environmentally friendly and harmless products are currently being studied and developed. The corrosion inhibition properties of caffeine (1,3,7-trimethylxanthine) on copper corrosion in aqueous chloride solution (3.5?wt.% NaCl) are analysed here using stationary and transient electrochemical methods, and a theoretical study based on density functional theory is carried out. Caffeine is a very competitive compared to the chemical inhibitors that are often used for copper protection. Electrochemical and impedance experiments reveal that the protective efficiency of caffeine reaches a value of 96% at a concentration of 10^?2?mol L^?1. Based on these results, the Langmuir model appears to be the best representation of the adsorption of caffeine onto the copper surface. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and X-ray diffraction (XRD) were used to determine the surface morphology and the chemical composition of the copper surface in chloride media, in the absence and presence of caffeine. The results show the development of a mechanism of corrosion inhibition. In order to confirm the correlation between the inhibitory effect and the molecular structure of caffeine, quantum chemical parameters are used to calculate its electronic properties.     

Investigation of PSt-MWCNT concentration on epoxyacrylate photopolymerization and conductivity of polymer films

Photopolymerization kinetics and conductivity changes of epoxyacrylate composites for various loading modified PSt-MWCNT weight fractions changing from 0.0025 to 0.2 wt.% were evaluated by performing photo differential scanning calorimetry (photo-DSC) and four point conductivity measurements. 0.2% PSt-MWCNT additive polymeric films had their electrical conductivity boosted by 6% more than non-additive polymeric films.     

Improvements in microstructural,mechanical, and biocompatibility properties of nano-sized hydroxyapatites doped with yttrium and fluoride

Hydroxyapatite was doped with Y³⁺ (2.5, 5 and 7.5 mol%) and F⁻ (2.5 mol%) ions (2.5YFHA, 5YFHA, 7.5YFHA, respectively) to compare its structural and mechanical properties and cellular response with pure-hydroxyapatite. No second phases were observed by X-ray diffraction spectra of 2.5YFHA. Doped hydroxyapatites had F⁻ bonds in addition to OH⁻ bonds. Hydroxyapatites sintered at 900 and 1100 °C were in nano-size. 7.5YFHA sintered at 1300 °C had the highest microhardness value. 2.5YFHA sintered at 1100 °C had the highest fracture toughness value. MTT viability assays showed high cell attachments on 2.5YFHA. Cell proliferation on 2.5YFHA and 5YFHA sintered at 1100 and 1300 °C was comparable with the control after 5-day culture. The highest ALP production and calcium deposition were observed on all hydroxyapatites sintered at 1100 °C. 2.5YFHA sintered at 1100 °C can be an alternative for hydroxyapatite in orthopedic applications.     

Tensile Bond Strength of a Highly Cross-Linked Denture Tooth to the Compression-Molded and Injection-Molded Denture Base Polymers

This study compared tensile bond strengths between conventional compression-molded heat (HC)-, auto (AP)-, and microwave-polymerized (MC) poly(methyl methacrylate)-based denture resins and a relatively new injection-molded, microwave-polymerized polyurethane based resin (MI) bonded to a highly cross-linked denture tooth. In the first part of the experiments, denture teeth were used as received. In the second part, they were treated with dichloromethane to see its effect on bonding of conventional denture bases (HCS and APS). Bond strength was tested in tension according to ADA specification No.15. The results showed that the HC group failed cohesively because of higher interface bonding (49.95 MPa) compared with those of the others (AP: 25.41 MPa; MC: 22.06 MPa; MI: 20.02 MPa). The application of dichloromethane improved bond strengths of HCS and APS groups (60.61 and 32.03 MPa, respectively). It was suggested that dichloromethane could be applied on the denture teeth ridge lap area prior to denture base processing to enhance adhesion between the tooth/resin.     

Impacts of impregnation with Imersol-Aqua on the compression strength of some solid wood materials

The aim of this study was to investigate the effects of impregnation with Imersol-Aqua on the compression strength of some solid wood materials. For this aim, Oriental beech (Fagus orientalis Lipsky), European oak (Quercus petrea Liebl.), Scotch pine (Pinus sylvestris Lipsky), Uludag fir (Abies Bornmülleriana Mattf.), Oriental spruce (Picea orientalis Lipsky) and Lombardy poplar (Populus nigra Lipsky) wood samples were prepared according to TS 2595 and impregnated with Imersol-Aqua, commonly being used in construction wood materials by the method of short, medium and long-term of dipping according to ASTM D 1413 and producers’ definition. After the impregnation process, compression strength was measured according to TS 2595. Consequently, among the non-impregnated wood materials, the highest compression strength was obtained in beech and pine samples. Compression strength at this situation from the highest to lowest can be enumerated beech, pine, oak, spruce, fir and poplar. With regard to the impregnation period, the sequence form the highest to lowest was as long-term, medium-term and short-term dipping. In the interaction of wood material and impregnation period, the highest compression strength values were obtained in Scotch pine (71.220 N mm⁻²) impregnated with long-term dipping method whereas the lowest in Lombardy poplar (35.710 N mm⁻²) impregnated with short-term dipping method.

In consequence, in the massive constructions and furniture elements that the compression strength after the impregnation is of great concern, long-term impregnation of solid wood material could be recommended.     

Switched-capacitor resonator structure with improved performance

A novel switched-capacitor resonator circuit is proposed. Its centre frequency is insensitive to the finite bandwidth and gain of the opamps used