Wet-Spun Trojan Horse Cell Constructs for Engineering Muscle

Engineering of 3D regenerative skeletal muscle tissue constructs (skMTCs) using hydrogels containing muscle precursor cells (MPCs) is of potential benefit for repairing Volumetric Muscle Loss (VML) arising from trauma (e.g., road/industrial accident, war injury) or for restoration of functional muscle mass in disease (e.g., Muscular Dystrophy, muscle atrophy). Additive Biofabrication (AdBiofab) technologies make possible fabrication of 3D regenerative skMTCs that can be tailored to specific delivery requirements of VML or functional muscle restoration. Whilst 3D printing is useful for printing constructs of many tissue types, the necessity of a balanced compromise between cell type, required construct size and material/fabrication process cyto-compatibility can make the choice of 3D printing a secondary alternative to other biofabrication methods such as wet-spinning. Alternatively, wet-spinning is more amenable to formation of fibers rather than (small) layered 3D-Printed constructs. This study describes the fabrication of biosynthetic alginate fibers containing MPCs and their use for delivery of dystrophin-expressing cells to dystrophic muscle in the mdx mouse model of Duchenne Muscular Dystrophy (DMD) compared to poly(DL-lactic-co-glycolic acid) copolymer (PLA:PLGA) topically-seeded with myoblasts. In addition, this study introduces a novel method by which to create 3D layered wet-spun alginate skMTCs for bulk mass delivery of MPCs to VML lesions. As such, this work introduces the concept of “Trojan Horse” Fiber MTCs (TH-fMTCs) and 3d Mesh-MTCs (TH-mMTCs) for delivery of regenerative MPCs to diseased and damaged muscle, respectively

Selected ions and major and trace elements as contaminants in coalwaste dump water from the Lower and Upper Silesian Coal Basins (Poland)

Many temporary and permanent reservoirs of water occur on or near coal-waste dumps in the Lower- and Upper Silesian Coal Basins (Poland). Little or nothing is known of the degree to which their water chemistry might reflect (i) reservoir type, i.e., whether permanent or temporary, (ii) level of coal-waste thermal activity, i.e., whether inactive or self-heating or burnt-out or (iii) region, i.e., whether the dumps are in Upper- or Lower Silesia. To provide some answers, concentrations of selected ions (NH4 ?, HCO3 -, F-, Cl-, Br-, NO2-, NO3 -, PO43-,SO4 2-) were determined by ion chromatography and of nineteen elements (Al, B, Ba, Ca, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Na, P, Pb, S, Si, Sr, Zn) by inductively coupled plasma mass spectrometry (ICP-MS). The data allow a number of the following observations. When permanent reservoirs are considered, there is a clear relationship between concentrations of ions and major and trace elements and dump thermal activity. The highest concentrations occur where the thermal activity is high as inorganic components are transformed into more water-soluble forms. As dump thermal activity shows a regional pattern, it follows also that elemental and ion concentrations in the dump waters show significant regional differences. In temporary reservoirs, concentrations of ions and major and trace elements are much lower and any correlations between components less significant than in the permanent reservoirs; these reservoirs exist for too short a time for any balance between coal wasteand water components to be established

In vitro growth and differentiation of primary myoblasts on thiophene based conducting polymers

Polythiophenes are attractive candidate polymers for use in synthetic cell scaffolds as they are amenable to modification of functional groups as a means by which to increase biocompatibility. In the current study we analysed the physical properties and response of primary myoblasts to three thiophene polymers synthesized from either a basic bithiophene monomer or from one of two different thiophene monomers with alkoxy functional groups. In addition, the effect of the dopants pTS- and ClO4 - was investigated. In general, it was found that pTS- doped polymers were significantly smoother and tended to be more hydrophilic than their ClO 4 - doped counterparts, demonstrating that the choice of dopant significantly affects the polythiophene physical properties. These properties had a significant effect on the response of primary myoblasts to the polymer surfaces; LDH activity measured from cells harvested at 24 and 48 h post-seeding revealed significant differences between numbers of cells attaching to the different thiophene polymers, whilst all of the polymers equally supported cell doubling over the 48 h period. Differences in morphology were also observed, with reduced cell spreading observed on polymers with alkoxy groups. In addition, significant differences were seen in the polymers\u27 ability to support myoblast fusion. In general pTS- doped polymers were better able to support fusion than their ClO4 - doped counterparts. These studies demonstrate that modification of thiophene polymers can be used to promote specific cellular response (e.g. proliferation over differentiation) without the use of biological agents. 2013 The Royal Society of Chemistry

Sterol biosensor reveals LAM-family Ltc1-dependent sterol flow to endosomes upon Arp2/3 inhibition.

Sterols are crucial components of biological membranes, which are synthetized in the ER and accumulate in the plasma membrane (PM). Here, by applying a genetically encoded sterol biosensor (D4H), we visualize a sterol flow between PM and endosomes in the fission yeast Schizosaccharomyces pombe. Using time-lapse and correlative light-electron microscopy, we found that inhibition of Arp2/3-dependent F-actin assembly promotes the reversible relocalization of D4H from the PM to internal sterol-rich compartments (STRIC) labeled by synaptobrevin Syb1. Retrograde sterol internalization to STRIC is independent of endocytosis or an intact Golgi, but depends on Ltc1, a LAM/StARkin-family protein localized to ER-PM contact sites. The PM in ltc1Δ cells over-accumulates sterols and upon Arp2/3 inhibition forms extended ER-interacting invaginations, indicating that sterol transfer contributes to PM size homeostasis. Anterograde sterol movement from STRIC is independent of canonical vesicular trafficking but requires Arp2/3, suggesting a novel role for this complex. Thus, transfer routes orthogonal to vesicular trafficking govern the flow of sterols in the cell

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms