Communicating cardiovascular risk based on individual vascular age (VA) is a well acknowledged concept in patient education and disease prevention. VA may be derived functionally, e.g. by measurement of pulse wave velocity (PWV), or morphologically, e.g. by assessment of carotid intima-media thickness (cIMT). The purpose of this study was to investigate whether both approaches produce similar results. Within the context of the German subset of the EUROASPIRE IV survey, 501 patients with coronary heart disease underwent (a) oscillometric PWV measurement at the aortic, carotid-femoral and brachial-ankle site (PWVao, PWVcf, PWVba) and derivation of the aortic augmentation index (AIao); (b) bilateral cIMT assessment by high-resolution ultrasound at three sites (common, bulb, internal). Respective VA was calculated using published equations. According to VA derived from PWV, most patients exhibited values below chronological age indicating a counterintuitive healthier-than-anticipated vascular status: for VA(PWVao) in 68% of patients; for VA\(_{AIao}\) in 52% of patients. By contrast, VA derived from cIMT delivered opposite results: e.g. according to VA\(_{total-cIMT}\) accelerated vascular aging in 75% of patients. To strengthen the concept of VA, further efforts are needed to better standardise the current approaches to estimate VA and, thereby, to improve comparability and clinical utility.

Background The spectrum of indications for the use of membranes and scaffolds in the field of oral and maxillofacial surgery includes, amongst others, guided bone regeneration (GBR). Currently available membrane systems face certain disadvantages such as difficult clinical handling, inconsistent degradation, undirected cell growth and a lack of stability that often complicate their application. Therefore, new membranes which can overcome these issues are of great interest in this field. Methods In this pilot study, we investigated polycaprolactone (PCL) scaffolds intended to enhance oral wound healing by means of melt electrospinning writing (MEW), which allowed for three-dimensional (3D) printing of micron scale fibers and very exact fiber placement. A singular set of box-shaped scaffolds of different sizes consisting of medical-grade PCL was examined and the scaffolds’ morphology was evaluated via scanning electron microscopy (SEM). Each prototype sample with box sizes of 225 μm, 300 μm, 375 μm, 450 μm and 500 μm was assessed for cytotoxicity and cell growth by seeding each scaffold with human osteoblast-like cell line MG63. Results All scaffolds demonstrated good cytocompatibility according to cell viability, protein concentration, and cell number. SEM analysis revealed an exact fiber placement of the MEW scaffolds and the growth of viable MG63 cells on them. For the examined box-shaped scaffolds with pore sizes between 225 μm and 500 μm, a preferred box size for initial osteoblast attachment could not be found. Conclusions These well-defined 3D scaffolds consisting of medical-grade materials optimized for cell attachment and cell growth hold the key to a promising new approach in GBR in oral and maxillofacial surgery.

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Insulin receptors were solubilized from rat liver microsomes by the nonionic detergent Triton X-100. After gel filtration of the extract on Sepharose CL-6B, two insulin-binding species (peak I and peak li) were obtained. The structure and binding properties of both peaks were characterized. Gel filtration yielded Stokes radii of 9.2 nm (peak I) and 8.0 nm (peak Il). Both peaks were glycoproteins. At 4°C peak 1 showed optimal insulin binding at pH 8.0 and high ionic strength. In contrast, peak li bad its binding optimum at pH 7.0 and low ionic strength, where peak I bindingwas minimal. For peak I the change in insulin binding under different conditions of pH and ionic strength was due to a change in receptor affinity only. For peak 11 an additional change in receptor number was found. Both peaks yielded non-linear Scatchard plots under most of the buffer conditions examined. At their binding optima at 4 oc the high affinity dissociation constants were 0.50 nM (peak I) and 0.55 nM (peak II). Sodium dodecyl sulfatejpolyacrylamide gel electrophoresis of peak I revealed five receptor bands with Mr 400000, 365000, 320000, 290000, and 245000 under non-reducing conditions. For peak II two major receptor bands with M\(_r\) 210000 and 115000 were found. The peak II receptor bands were also obtained aftermild reduction of peak I. After complete reduction both peaks showed one major receptor band with M\(_r\) 130000. The reductive generation of the peak II receptor together with molecular mass estimations suggest that the peak I receptor is the disulfide-linked dimer of the peak II receptor. Thus, Triton extracts from rat liver microsomes contain two receptor species, which are related, but differ considerably in their size and insulin-binding properties.

Although the DNA methyltransferase 2 family is highly conserved during evolution and recent reports suggested a dual specificity with stronger activity on transfer RNA (tRNA) than DNA substrates, the biological function is still obscure. We show that the Dictyostelium discoideum Dnmt2-homologue DnmA is an active tRNA methyltransferase that modifies C38 in \(tRNA^{Asp(GUC)}\) in vitro and in vivo. By an ultraviolet-crosslinking and immunoprecipitation approach, we identified further DnmA targets. This revealed specific tRNA fragments bound by the enzyme and identified \(tRNA^{Glu(CUC/UUC)}\) and \(tRNA^{Gly(GCC)}\) as new but weaker substrates for both human Dnmt2 and DnmA in vitro but apparently not in vivo. Dnmt2 enzymes form transient covalent complexes with their substrates. The dynamics of complex formation and complex resolution reflect methylation efficiency in vitro. Quantitative PCR analyses revealed alterations in dnmA expression during development, cell cycle and in response to temperature stress. However, dnmA expression only partially correlated with tRNA methylation in vivo. Strikingly, dnmA expression in the laboratory strain AX2 was significantly lower than in the NC4 parent strain. As expression levels and binding of DnmA to a target in vivo are apparently not necessarily accompanied by methylation, we propose an additional biological function of DnmA apart from methylation.