A customizable 3D printed device for enzymatic removal of drugs in water

The infiltration of drugs into water is a key global issue, with pharmaceuticals being detected in all nearly aqueous systems at often alarming concentrations. Pharmaceutical contamination of environmental water supplies has been shown to negatively impact ecological equilibrium and pose a risk to human health. In this study, we design and develop a novel system for the removal of drugs from water, termed as Printzyme. The device, fabricated with stereolithography (SLA) 3D printing, immobilises laccase sourced from Trametes Versicolor within a poly(ethylene glycol) diacrylate hydrogel. We show that SLA printing is a sustainable method for enzyme entrapment under mild conditions, and measure the stability of the system when exposed to extremes of pH and temperature in comparison to free laccase. When tested for its drug removal capacity, the 3D printed device substantially degraded two dissolved drugs on the European water pollution watch list. When configured in the shape of a torus, the device effectively removed 95% of diclofenac and ethinylestradiol from aqueous solution within 24 and 2 h, respectively, more efficiently than free enzyme. Being customizable and reusable, these 3D printed devices could help to efficiently tackle the world's water pollution crisis, in a flexible, easily scalable, and cost-efficient manner

Selective autophagy maintains centrosome integrity and accurate mitosis by turnover of centriolar satellites

The centrosome is the master orchestrator of mitotic spindle formation and chromosome segregation in animal cells. Centrosome abnormalities are frequently observed in cancer, but little is known of their origin and about pathways affecting centrosome homeostasis. Here we show that autophagy preserves centrosome organization and stability through selective turnover of centriolar satellite components, a process we termed doryphagy. Autophagy targets the satellite organizer PCM1 by interacting with GABARAPs via a C-terminal LIR motif. Accordingly, autophagy deficiency results in accumulation of large abnormal centriolar satellites and a resultant dysregulation of centrosome composition. These alterations have critical impact on centrosome stability and lead to mitotic centrosome fragmentation and unbalanced chromosome segregation. Our findings identify doryphagy as an important centrosome-regulating pathway and bring mechanistic insights to the link between autophagy dysfunction and chromosomal instability. In addition, we highlight the vital role of centriolar satellites in maintaining centrosome integrity

Assessment of genetic diversity among seed transfer zones for multiple grassland plant species across Germany

Species diversity and intraspecific genetic diversity play a critical role in conservation and restoration of grassland ecosystems. To maintain regional adaptations of native wild plants, seeds for restoration projects are produced regionally. The delineation of regions is organised by seed transfer zones (STZs). Generalised STZs that apply uniformly to many species have been established in several European countries. Ideally, generalised STZs should be based on comprehensive data of intraspecific genetic and phenotypic diversity for a larger number of species. However, such underlying data is missing. The project RegioDiv aims to fill this gap and generate empirical data on genetic variation of multiple grassland plant species across Germany. Here we describe the driving principles and main methods of the project. A total of 33 species were collected at an average density of ∼1 sample/1000 km2 across the 22 existing STZs, and a total of 11,976 samples were genotyped with SNP markers. The analysis of genetic population structure included cluster analysis and analyses of isolation-by-distance and isolation-by-environment. An exemplary within-species analysis for Agrostis capillaris, a widespread grass, revealed five intraspecific genetic clusters, distributed in spatially coherent ranges that did not fully match the STZs. Most of the STZs differed genetically following a pattern of isolation-by-distance and isolation-by-environment. In an across-species analysis, genetic differentiation was affected by mating system and ploidy. Outcrossed and polyploid species were less differentiated than self-compatible and diploid species. However, genetic differentiation did not significantly differ between grasses and herbs, highlighting the variability among species within these groups. The dataset of the RegioDiv project will advance both basic and applied research on genetic variation of grassland plant species. The results will allow the assessment of the current German STZ system and guide potential improvements

Culture of human mesenchymal stem cells on microcarriers in a 5 l stirred-tank bioreactor

This article was published in the journal, Biotechnology Letters [© Springer Science+Business Media] and the definitive version is available at: http://dx.doi.org/10.1007/s10529-013-1211-9For the first time, fully functional human mesenchymal stem cells (hMSCs) have been cultured at the litre-scale on microcarriers in a stirred-tank 5 l bioreactor, (2.5 l working volume) and were harvested via a potentially scalable detachment protocol that allowed for the successful detachment of hMSCs from the cell-microcarrier suspension. Over 12 days, the dissolved O2 concentration was >45 % of saturation and the pH between 7.2 and 6.7 giving a maximum cell density in the 5 l bioreactor of 1.7 × 105 cells/ml; this represents >sixfold expansion of the hMSCs, equivalent to that achievable from 65 fully-confluent T-175 flasks. During this time, the average specific O2 uptake of the cells in the 5 l bioreactor was 8.1 fmol/cell h and, in all cases, the 5 l bioreactors outperformed the equivalent 100 ml spinner-flasks run in parallel with respect to cell yields and growth rates. In addition, yield coefficients, specific growth rates and doubling times were calculated for all systems. Neither the upstream nor downstream bioprocessing unit operations had a discernible effect on cell quality with the harvested cells retaining their immunophenotypic markers, key morphological features and differentiation capacity