Characterization of Thin Polymer Layer Prepared from Liposomes and Polyelectrolytes for TGF-β Release in Tissue Engineering.

Implant-integrated drug delivery systems that enable the release of biologically active factors can be part of an in situ tissue engineering approach to restore biological function. Implants can be functionalized with drug-loaded nanoparticles through a layer-by-layer assembly. Such coatings can release biologically active levels of growth factors.

2PP-Hydrogel Covered Electrodes to Compensate for Media Effects in the Determination of Biomass in a Capillary Wave Micro Bioreactor.

Microbioreactors increase information output in biopharmaceutical screening applications because they can be operated in parallel without consuming large quantities of the pharmaceutical formulations being tested. A capillary wave microbioreactor (cwMBR) has recently been reported, allowing cost-efficient parallelization in an array that can be activated for mixing as a whole. Although impedance spectroscopy can directly distinguish between dead and viable cells, the monitoring of cells in suspension within bioreactors is challenging because the signal is influenced by the potentially varying properties of the culture medium.

Mechanical, Biological and In Vitro Degradation Investigation of Braided Scaffolds for Tendon and Ligament Tissue Engineering Based on Different Polycaprolactone Materials with Chitosan-Graft-PCL Surface Modification.

Injuries to tendons and ligaments are highly prevalent in the musculoskeletal system. Current treatments involve autologous transplants with limited availability and donor site morbidity. Tissue engineering offers a new approach through temporary load-bearing scaffolds.

Topographically and Chemically Enhanced Textile Polycaprolactone Scaffolds for Tendon and Ligament Tissue Engineering.

The use of tissue engineering to address the shortcomings of current procedures for tendons and ligaments is promising, but it requires a suitable scaffold that meets various mechanical, degradation-related, scalability-related, and biological requirements. Macroporous textile scaffolds made from appropriate fiber material have the potential to fulfill the first three requirements. This study aimed to investigate the biocompatibility, sterilizability, and functionalizability of a multilayer braided scaffold.

Application of electrospun chitosan-based nanofibers as immobilization matrix for biomolecules.

Nanofiber meshes from electrospun chitosan, highly modified with biotin and arylazides, are well-suited for application as enzyme immobilization matrices. To test this, catalytically active biomolecules were immobilized onto photocrosslinked nanofibrous nonwovens consisting mainly of biotinylated fungal chitosan and a small amount (10 w%) of poly ethylene oxide. In this study, we show that over 10 μg eugenol oxidase per milligram dry polymer matrix can be loaded on UV-crosslinked chitosan nanofibers.

Evaluation of the Immune Response to Chitosan--poly(caprolactone) Biopolymer Scaffolds.

Biomimetic scaffolds recreating key elements of the architecture and biological activity of the extracellular matrix have enormous potential for soft tissue engineering applications. Combining appropriate mechanical properties with select biological cues presents a challenge for bioengineering, as natural materials are most bioactive but can lack mechanical integrity, while synthetic polymers have strength but are often biologically inert. Blends of synthetic and natural materials, aiming to combine the benefits of each, have shown promise but inherently require a compromise, diluting down favorable properties in each polymer to accommodate the other.

Note on uncertainty in Monte Carlo dose calculations and its relation to microdosimetry.

Purpose: The Type A standard uncertainty in Monte Carlo (MC) dose calculations is usually determined using the "history by history" method. Its applicability is based on the assumption that the central limit theorem (CLT) can be applied such that the dispersion of repeated calculations can be modeled by a Normal distribution. The justification for this assumption, however, is not obvious.

Adhesion Forces of Oral Bacteria to Titanium and the Correlation with Biophysical Cellular Characteristics.

Bacterial adhesion to dental implants is the onset for the development of pathological biofilms. Reliable characterization of this initial process is the basis towards the development of anti-biofilm strategies. In the present study, single-cell force spectroscopy (SCFS), by means of an atomic force microscope connected to a microfluidic pressure control system (FluidFM), was used to comparably measure adhesion forces of different oral bacteria within a similar experimental setup to the common implant material titanium.

Polycaprolactone-Based 3D-Printed Scaffolds as Potential Implant Materials for Tendon-Defect Repair.

Chronic tendon ruptures are common disorders in orthopedics. The conventional surgical methods used to treat them often require the support of implants. Due to the non-availability of suitable materials, 3D-printed polycaprolactone (PCL) scaffolds were designed from two different starting materials as suitable candidates for tendon-implant applications.

Layer-by-Layer Deposition of 2D CdSe/CdS Nanoplatelets and Polymers for Photoluminescent Composite Materials.

Two-dimensional (2D) semiconductor nanoplatelets (NPLs) are strongly photoluminescent materials with interesting properties for optoelectronics. Especially their narrow photoluminescence paired with a high quantum yield is promising for light emission applications with high color purity. However, retaining these features in solid-state thin films together with an efficient encapsulation of the NPLs is a challenge, especially when trying to achieve high-quality films with a defined optical density and low surface roughness.

Spatially and Temporally Controllable BMP-2 and TGF-β Double Release From Polycaprolactone Fiber Scaffolds via Chitosan-Based Polyelectrolyte Coatings.

Temporally and spatially controlled growth factor release from a polycaprolactone fiber mat, which also provides a matrix for directional cell colonization and infiltration, could be a promising regenerative approach for degenerated tendon-bone junctions. For this purpose, polycaprolactone fiber mats were coated with tailored chitosan-based nanogels to bind and release the growth factors bone morphogenetic protein 2 (BMP-2) and transforming growth factor-β (TGF-β), respectively. In this work we provide meaningful data for the understanding of the drug delivery performance and sterilizability of novel implant prototypes in order to lay the foundation for testing.

Conditioning with fludarabine and treosulfan compared to FLAMSA-RIC in allogeneic stem cell transplantation for myeloid malignancies: a retrospective single-center analysis.

Reduced intensity conditioning (RIC) and reduced toxicity conditioning (RTC) regimens enable allogeneic hematopoietic stem cell transplantation (alloSCT) to more patients due to reduction in transplant-related mortality (TRM). The conditioning regimens with fludarabine and treosulfan (Flu/Treo) or fludarabine, amsacrine, cytarabine (FLAMSA)-RIC have shown their efficacy and tolerability in various malignancies. So far, no prospective study comparing the two regimens is available.

Thermoresponsive Glycopolypeptide Containing Block Copolymers, Particle Formation, and Lectin Interaction.

Amphiphilic block copolymers with a thermoresponsive poly(N-isopropylacrylamide) block and a glycopeptide block are synthesized and particle formation as well as interaction of the glyco-corona with lectins is investigated. The synthetic route comprises the preparation of block copolymers by N-carboxyanhydride polymerization and subsequent deprotection to obtain pH- and thermoresponsive poly(l-glutamic acid)-b-poly(N-isopropylacrylamide) (pGA-b-pNIPAM), which is then further modified with different amino sugars by a versatile coupling method with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholin-4-ium chloride (DMT-MM). The glycosylated pGA-b-pNIPAM block copolymers are investigated with regard to cloud point temperatures (T ), particle size, and stability.

Development of Neuronal Guidance Fibers for Stimulating Electrodes: Basic Construction and Delivery of a Growth Factor.

State-of-the-art treatment for sensorineural hearing loss is based on electrical stimulation of residual spiral ganglion neurons (SGNs) with cochlear implants (CIs). Due to the anatomical gap between the electrode contacts of the CI and the residual afferent fibers of the SGNs, spatial spreading of the stimulation signal hampers focused neuronal stimulation. Also, the efficiency of a CI is limited because SGNs degenerate over time due to loss of trophic support.

Optimization of Critical Parameters for Carbodiimide Mediated Production of Highly Modified Chitosan.

An optimization of the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and hydroxy benzotriazole mediated conjugation of the polysaccharide chitosan with functional carboxylic acids was shown. Optimal parameters that enable resource-efficient synthesis of highly functionalized chitosan were identified. In particular, use of only catalytic instead of stoichiometric amounts of hydroxy benzotriazole and tight control of pH in reaction mixture resulted in highly efficient incorporation of the desired moieties as side chains in chitosan.

Enzyme-Responsive Nanoparticles and Coatings Made from Alginate/Peptide Ciprofloxacin Conjugates as Drug Release System.

Infection-controlled release of antibacterial agents is of great importance, particularly for the control of peri-implant infections in the postoperative phase. Polymers containing antibiotics bound via enzymatically cleavable linkers could provide access to drug release systems that could accomplish this. Dispersions of nanogels were prepared by ionotropic gelation of alginate with poly-l-lysine, which was conjugated with ciprofloxacin as model drug via a copper-free 1,3-dipolar cycloaddition (click reaction).

ELISA- and Activity Assay-Based Quantification of BMP-2 Released Can Be Biased by Solubility in "Physiological" Buffers and an Interfering Effect of Chitosan.

Chitosan nanogel-coated polycaprolactone (PCL) fiber mat-based implant prototypes with tailored release of bone morphogenic protein 2 (BMP-2) are a promising approach to achieve implant-mediated bone regeneration. In order to ensure reliable release results, the robustness of a commercially available ELISA for -derived BMP-2 and the parallel determination of BMP-2 recovery using a quantitative biological activity assay were investigated within a common release setup, with special reference to solubility and matrix effects. Without bovine serum albumin and Tween 20 as solubilizing additives to release media buffed at physiological pH, BMP-2 recoveries after release were notably reduced.

The use of dose quantities in radiological protection: ICRP publication 147 Ann ICRP 50(1) 2021.

The International Commission on Radiological Protection has recently published a report (ICRP Publication 147;, 2021) on the use of dose quantities in radiological protection, under the same authorship as this Memorandum. Here, we present a brief summary of the main elements of the report. ICRP Publication 147 consolidates and clarifies the explanations provided in the 2007 ICRP Recommendations (Publication 103) but reaches conclusions that go beyond those presented in Publication 103.

Enzyme Degradable Polymersomes from Chitosan-g-[poly-l-lysine-block-ε-caprolactone] Copolymer.

The scope of this study includes the synthesis of chitosan-g-[peptide-poly-ε-caprolactone] and its self-assembly into polymeric vesicles employing the solvent shift method. In this way, well-defined core-shell structures suitable for encapsulation of drugs are generated. The hydrophobic polycaprolactone side-chain and the hydrophilic chitosan backbone are linked via an enzyme-cleavable peptide.

Varying the sustained release of BMP-2 from chitosan nanogel-functionalized polycaprolactone fiber mats by different polycaprolactone surface modifications.

Polycaprolactone (PCL) fiber mats with different surface modifications were functionalized with a chitosan nanogel coating to attach the growth factor human bone morphogenetic protein 2 (BMP-2). Three different hydrophilic surface modifications were compared with regard to the binding and in vitro release of BMP-2. The type of surface modification and the specific surface area derived from the fiber thickness had an important influence on the degree of protein loading.

Understanding Player Load: Meanings and Limitations.

We present a critical reflection on the mechanical variable Player Load, which is based on acceleration data and commonly used in sports. Our motivation to write this paper came from the difficulties that we encountered in the calculation and interpretation of Player Load using our own data, since we did not use the Catapult Sports equipment, which is a merchandise of the company that proposed this variable. We reviewed existing literature in order to understand Player Load better; we found many inconsistencies in PL calculation methods and in the meanings attached to it.

Sustained release of TGF-β from polysaccharide nanoparticles induces chondrogenic differentiation of human mesenchymal stromal cells.

Medical treatment of certain diseases and biomedical implants are tending to use delivery systems on the nanoscale basis for biologically active factors including drugs (e. g. antibiotics) or growth factors.

TGF-β3 Loaded Electrospun Polycaprolacton Fibre Scaffolds for Rotator Cuff Tear Repair: An in Vivo Study in Rats.

Biological factors such as TGF-β3 are possible supporters of the healing process in chronic rotator cuff tears. In the present study, electrospun chitosan coated polycaprolacton (CS-g-PCL) fibre scaffolds were loaded with TGF-β3 and their effect on tendon healing was compared biomechanically and histologically to unloaded fibre scaffolds in a chronic tendon defect rat model. The biomechanical analysis revealed that tendon-bone constructs with unloaded scaffolds had significantly lower values for maximum force compared to native tendons.