Reversible 2D networks of oligo(ε-caprolactone) at the air-water interface.

Hydroxyl terminated oligo(ε-caprolactone) (OCL) monolayers were reversibly cross-linked forming two dimensional networks (2D) at the air-water interface. The equilibrium reaction with glyoxal as the cross-linker is pH-sensitive. Pronounced contraction in the area of the prepared 2D OCL films in dependence of surface pressure and time revealed the process of the reaction.

Fibroblast origin shapes tissue homeostasis, epidermal differentiation, and drug uptake.

Preclinical studies frequently lack predictive value for human conditions. Human cell-based disease models that reflect patient heterogeneity may reduce the high failure rates of preclinical research. Herein, we investigated the impact of primary cell age and body region on skin homeostasis, epidermal differentiation, and drug uptake.

Comparison of exercise electrocardiography and magnetocardiography for detection of coronary artery disease using ST-segment fluctuation score.

Background: Exercise electrocardiography (ECG) is frequently used as a diagnostic measure in patients with suspected coronary artery disease (CAD). However, it has low sensitivity for the detection of CAD. Magnetocardiography (MCG) has been proposed as an alternative tool to accurately diagnose CAD.

Generation of a human induced pluripotent stem cell line (BIHi002-A) from a patient with CLCN7-related infantile malignant autosomal recessive osteopetrosis.

Autosomal recessive osteopetrosis (ARO) is a genetic bone disease that can be caused by mutations in the CLCN7 gene preventing osteoclast-mediated bone resorption. We generated a human induced pluripotent stem cell (hiPSC) line, BIHi002-A, from peripheral blood mononuclear cells of an ARO patient carrying the CLCN7 mutations c.875G>A and c.

Therapeutic potential of menstrual blood-derived endometrial stem cells in cardiac diseases.

Despite significant developments in medical and surgical strategies, cardiac diseases remain the leading causes of morbidity and mortality worldwide. Numerous studies involving preclinical and clinical trials have confirmed that stem cell transplantation can help improve cardiac function and regenerate damaged cardiac tissue, and stem cells isolated from bone marrow, heart tissue, adipose tissue and umbilical cord are the primary candidates for transplantation. During the past decade, menstrual blood-derived endometrial stem cells (MenSCs) have gradually become a promising alternative for stem cell-based therapy due to their comprehensive advantages, which include their ability to be periodically and non-invasively collected, their abundant source material, their ability to be regularly donated, their superior proliferative capacity and their ability to be used for autologous transplantation.

BloodSurf 2017: News from the blood-biomaterial frontier.

From stents and large-diameter vascular grafts, to mechanical heart valves and blood pumps, blood-contacting devices are enjoying significant clinical success owing to the application of systemic antiplatelet and anticoagulation therapies. On the contrary, research into material and device hemocompatibility aimed at alleviating the need for systemic therapies has suffered a decline. This research area is undergoing a renaissance fueled by recent fundamental insights into coagulation and inflammation that are offering new avenues of investigation, the growing recognition of the limitations facing existing therapeutic approaches, and the severity of the cardiovascular disorders epidemic.

Shear-induced platelet adherence and activation in an in-vitro dynamic multiwell-plate system.

Circulating blood cells are prone to varying flow conditions when contacting cardiovascular devices. For a profound understanding of the complex interplay between the blood components/cells and cardiovascular implant surfaces, testing under varying shear conditions is required. Here, we study the influence of arterial and venous shear conditions on the in vitro evaluation of the thrombogenicity of polymer-based implant materials.

Evaluation of Laser-Doppler-Fluxmetry for the diagnosis of microcirculatory disorders.

Background: The laser Doppler fluxmetry (LDF) is a non-invasive method to assess skin blood perfusion, measuring the flow of blood cells inside a tissue volume without harming the tissue. In the diagnosis of skin circulation disorders, the results of the LDF measurement are generally used in such a way that "normal" (or non-ill) or "pathological" values are achieved by comparison with a reference sample, for example of apparently healthy subjects.

Material And Methods: In this study, the values of LDF for the diagnosis of microcirculatory disorders in patients with coronary artery disease (n = 20) or in patients with microcirculatory disorders, already diagnosed by capillary microscopy (n = 46), were examined.

Collagen type-IV Langmuir and Langmuir-Schäfer layers as model biointerfaces to direct stem cell adhesion.

In biomaterial development, the design of material surfaces that mimic the extra-cellular matrix (ECM) in order to achieve favorable cellular instruction is rather challenging. Collagen-type IV (Col-IV), the major scaffolding component of Basement Membranes (BM), a specialized ECM with multiple biological functions, has the propensity to form networks by self-assembly and supports adhesion of cells such as endothelial cells or stem cells. The preparation of biomimetic Col-IV network-like layers to direct cell responses is difficult.

Modulating human mesenchymal stem cells using poly(n-butyl acrylate) networks in vitro with elasticity matching human arteries.

Non-swelling hydrophobic poly(n-butyl acrylate) network (cPnBA) is a candidate material for synthetic vascular grafts owing to its low toxicity and tailorable mechanical properties. Mesenchymal stem cells (MSCs) are an attractive cell type for accelerating endothelialization because of their superior anti-thrombosis and immune modulatory function. Further, they can differentiate into smooth muscle cells or endothelial-like cells and secret pro-angiogenic factors such as vascular endothelial growth factor (VEGF).

Metabolic activity testing can underestimate acute drug cytotoxicity as revealed by HepG2 cell clones overexpressing cytochrome P450 2C19 and 3A4.

Preclinical drug safety assessment includes in vitro studies with physiologically relevant cell cultures. As an in vitro system for hepatic toxicology testing, we have been generating cell clones of human hepatoblastoma cell line HepG2 by lentiviral transduction of phase I cytochrome P450 (CYP) enzymes. Here, we present a stable CYP2C19-overexpressing HepG2 cell clone (HepG2-2C19 C1) showing an enzyme activity of approximately 82 pmol x min x mg total cellular protein.

Langmuir Monolayers as Tools to Study Biodegradable Polymer Implant Materials.

Langmuir monolayers provide a fast and elegant route to analyze the degradation behavior of biodegradable polymer materials. In contrast to bulk materials, diffusive transport of reactants and reaction products in the (partially degraded) material can be neglected at the air-water interface, allowing for the study of molecular degradation kinetics in experiments taking less than a day and in some cases just a few minutes, in contrast to experiments with bulk materials that can take years. Several aspects of the biodegradation behavior of polymer materials, such as the interaction with biomolecules and degradation products, are directly observable.

Enhancement of human induced pluripotent stem cells adhesion through multilayer laminin coating.

Bioengineered cell substrates are a highly promising tool to govern the differentiation of stem cells in vitro and to modulate the cellular behavior in vivo. While this technology works fine for adult stem cells, the cultivation of human induced pluripotent stem cells (hiPSCs) is challenging as these cells typically show poor attachment on the bioengineered substrates, which among other effects causes substantial cell death. Thus, very limited types of surfaces have been demonstrated suitable for hiPSC cultures.

VueBox® perfusion analysis of contrast-enhanced ultrasound (CEUS) examinations in patients with primary hyperparathyroidism for preoperative detection of parathyroid gland adenoma.

Aim: Aim of this study was to firstly describe reproducible, objective perfusion parameters of contrast-enhanced ultrasound (CEUS) kinetics of parathyroid gland adenoma (PA) using perfusion analysis software (VueBox®, Bracco, Italy). Thereby the efficiency of quantitative CEUS for characterization of PA should be evaluated comparing US to postoperative histopathological findings after PA resection.

Material And Methods: 42 patients with symptoms/lab work suggestive of pHPT presented a parathyroid gland lesion in B-mode US, which was consequently analyzed by dynamic CEUS.

Remote ischemic preconditioning of the heart: Combining lower limb ischemia and electronic stimulation of the gastrocnemius muscle.

Background: Remote ischemic preconditioning (RIPC) has been demonstrated to induce potent cardioprotection in individuals experiencing coronary ischemia. A protocol combining limb ischemia and electronic muscle stimulation of the ischemic skeletal muscle (RIPC+), performed in advance of coronary artery occlusion, was superior in terms of infarct size reduction when compared to RIPC alone.

Methods: This study was performed to evaluate the benefit of RIPC + in humans compared to a standard RIPC protocol and a control group.

Magnetocardiography scoring system to predict the presence of obstructive coronary artery disease.

Background: Magnetocardiography (MCG) has been proposed as a non-invasive and functional technique with high accuracy for diagnosis of myocardial ischemia.

Objective: This study sought to develop a novel scoring system of MCG for predicting the presence of significant obstructive coronary artery disease (CAD).

Methods: In a training set of 108 subjects, predictors of ≥70% stenosis in at least one major coronary vessel were prospectively identified from MCG variables.

Synthesis of Well-Defined Dihydroxy Telechelics by (Co)polymerization of Morpholine-2,5-Diones Catalyzed by Sn(IV) Alkoxide.

Well-defined dihydroxy telechelic oligodepsipeptides (oDPs), which have a high application potential as building blocks for scaffold materials for tissue engineering applications or particulate carrier systems for drug delivery applications are synthesized by ring-opening polymerization (ROP) of morpholine-2,5-diones (MDs) catalyzed by 1,1,6,6-tetra-n-butyl-1,6-distanna-2,5,7,10-tetraoxacyclodecane (Sn(IV) alkoxide). In contrast to ROP catalyzed by Sn(Oct) , the usage of Sn(IV) alkoxide leads to oDPs, with less side products and well-defined end groups, which is crucial for potential pharmaceutical applications. A slightly faster reaction of the ROP catalyzed by Sn(IV) alkoxide compared to the ROP initiated by Sn(Oct) /EG is found.

Turning fibroblasts into cardiomyocytes: technological review of cardiac transdifferentiation strategies.

To date, no viable therapeutic options exist for the effective and sustained reversal of cardiac failure, other than heart transplantation and mechanical circulatory assist devices. Therefore, divergent strategies aiming at the de novo formation of contractile tissue, as a prerequisite for the restoration of cardiac pump function, are currently being pursued. Clinical trials involving the transplantation of somatic progenitor cells failed.

Epigenetic immune cell counting in human blood samples for immunodiagnostics.

Immune cell profiles provide valuable diagnostic information for hematologic and immunologic diseases. Although it is the most widely applied analytical approach, flow cytometry is limited to liquid blood. Moreover, either analysis must be performed with fresh samples or cell integrity needs to be guaranteed during storage and transport.

The predictive value of a modified Carpentier classification in patients with coincidental mitral regurgitation undergoing TAVI for severe aortic valve stenosis1.

Introduction: Concomitant mitral-regurgitation (MR) is frequently observed in patients undergoing trans-catheter aortic valve implantation (TAVI). The predictive value of MR etiology remains to be elucidated.

Methods: 600 patients with coincidental MR (≥moderate) undergoing TAVI were categorized according to a modified Carpentier classification [Groups: no/mild MR, n = 477; left atrial (LA) functional MR, n = 18; MR due to left ventricular dilatation, n = 29; degenerative MR, n = 50; MR with restricted leaflet motion n = 26].

Exceptionally Ductile and Tough Biomimetic Artificial Nacre with Gas Barrier Function.

Synthetic mimics of natural high-performance structural materials have shown great and partly unforeseen opportunities for the design of multifunctional materials. For nacre-mimetic nanocomposites, it has remained extraordinarily challenging to make ductile materials with high stretchability at high fractions of reinforcements, which is however of crucial importance for flexible barrier materials. Here, highly ductile and tough nacre-mimetic nanocomposites are presented, by implementing weak, but many hydrogen bonds in a ternary nacre-mimetic system consisting of two polymers (poly(vinyl amine) and poly(vinyl alcohol)) and natural nanoclay (montmorillonite) to provide efficient energy dissipation and slippage at high nanoclay content (50 wt%).

A multifunctional multimaterial system for on-demand protein release.

In order to provide best control of the regeneration process for each individual patient, the release of protein drugs administered during surgery may need to be timely adapted and/or delayed according to the progress of healing/regeneration. This study aims to establish a multifunctional implant system for a local on-demand release, which is applicable for various types of proteins. It was hypothesized that a tubular multimaterial container kit, which hosts the protein of interest as a solution or gel formulation, would enable on-demand release if equipped with the capacity of diameter reduction upon external stimulation.

Tumor targeting with pH-responsive poly(2-oxazoline)-based nanogels for metronomic doxorubicin treatment.

The synthesis of a new nanogel drug carrier system loaded with the anti-cancer drug doxorubicin (DOX) is presented. Poly(2-oxazoline) (POx) based nanogels from block copolymer micelles were cross-linked and covalently loaded with DOX using pH-sensitive Schiff' base chemistry. DOX loaded POx based nanogels showed a toxicity profile comparable to the free drug, while unloaded drug carriers showed no toxicity.

Comparison of two substrate materials used as negative control in endothelialization studies: Glass versus polymeric tissue culture plate.

The endothelialization of synthetic surfaces applied as cardiovascular implant materials is an important issue to ensure the anti-thrombotic quality of a biomaterial. However, the rapid and constant development of a functionally-confluent endothelial cell monolayer is challenging. In order to investigate the compatibility of potential implant materials with endothelial cells several in vitro studies are performed.