Introducing and embedding innovation practices in a UK medical engineering degree course

Exposing medical engineering students to innovation and entrepreneurial practices and training them in concepts and models encountered in industry in a simulated start-up company environment allowed students to explore whether this career route was of interest to them and is expected to enhance the employability of all participants. A module, MedTech BEST (Business and Entrepreneurial Skills Training), was developed to focus on the needs of the medical technology industry sector and piloted at the University of Leeds in 2016/2017. Students acquired the skills and knowledge to be able to pitch a hypothetical medical device product together with its supporting business case, developed over the course of the module, to a panel of experienced judges

Electrospun bioresorbable tissue repair scaffolds: From laboratory to clinic

The healing of soft tissue wounds and injury sites is a complex process requiring the participation of many different cells, tissues, proteins and tissue components in a coordinated manner. We describe the development of regenerative, electrospun, bioresorbable advanced material tissue scaffolds providing three dimensional (3D) structure for cells involved in the repair of soft tissue injuries. One product, EktoTherix™ provides a micron-scale 3D architecture to enhance the recruitment of reparative cells onto this temporary support and in this way the body's capacity to repair itself is utilised. EktoTherix and other electrospun tissue scaffolds have been translated from early stage laboratory work through manufacturing process development and clinical investigation

Phylogeography of a successful aerial disperser: the golden orb spider Nephila on Indian Ocean islands

Abstract Background The origin and diversification patterns of lineages across the Indian Ocean islands are varied due to the interplay of the complex geographic and geologic island histories, the varying dispersal abilities of biotas, and the proximity to major continental landmasses. Our aim was to reconstruct phylogeographic history of the giant orbweaving spider (Nephila) on western Indian Ocean islands (Madagascar, Mayotte, Réunion, Mauritius, Rodrigues), to test its origin and route of dispersal, and to examine the consequences of good dispersal abilities for colonization and diversification, in comparison with related spiders (Nephilengys) inhabiting the same islands, and with other organisms known for over water dispersal. We used mitochondrial (COI) and nuclear (ITS2) markers to examine phylogenetic and population genetic patterns in Nephila populations and species. We employed Bayesian and parsimony methods to reconstruct phylogenies and haplotype networks, respectively, and calculated genetic distances, fixation indices, and estimated clade ages under a relaxed clock model. Results Our results suggest an African origin of Madagascar Nephila inaurata populations via Cenozoic dispersal, and the colonization of the Mascarene islands from Madagascar. We find evidence of gene flow across Madagascar and Comoros. The Mascarene islands share a common 'ancestral' COI haplotype closely related to those found on Madagascar, but itself absent, or as yet unsampled, from Madagascar. Each island has one or more unique haplotypes related to the ancestral Mascarene haplotype. The Indian Ocean N. inaurata are genetically distinct from the African populations. Conclusions Nephila spiders colonized Madagascar from Africa about 2.5 (0.6-5.3) Ma. Our results are consistent with subsequent, recent and rapid, colonization of all three Mascarene islands. On each island, however, we detected unique haplotypes, consistent with a limited gene flow among the islands subsequent to colonization, a scenario that might be referred to as speciation in progress. However, due to relatively small sample sizes, we cannot rule out that we simply failed to collect Mascarene haplotypes on Madagascar, a scenario that might imply human mediated dispersal. Nonetheless, the former interpretation better fits the available data and results in a pattern similar to the related Nephilengys. Nephilengys, however, shows higher genetic divergences with diversification on more remote islands. That the better disperser of the two lineages, Nephila, has colonized more islands but failed to diversify, demonstrates how dispersal ability can shape both the patterns of colonization and formation of species across archipelagos.</p

Late Cretaceous Vicariance in Gondwanan Amphibians

Overseas dispersals are often invoked when Southern Hemisphere terrestrial and freshwater organism phylogenies do not fit the sequence or timing of Gondwana fragmentation. We used dispersal-vicariance analyses and molecular timetrees to show that two species-rich frog groups, Microhylidae and Natatanura, display congruent patterns of spatial and temporal diversification among Gondwanan plates in the Late Cretaceous, long after the presumed major tectonic break-up events. Because amphibians are notoriously salt-intolerant, these analogies are best explained by simultaneous vicariance, rather than by oceanic dispersal. Hence our results imply Late Cretaceous connections between most adjacent Gondwanan landmasses, an essential concept for biogeographic and palaeomap reconstructions

Predicting plant diversity patterns in Madagascar : understanding the effects of climate and land cover change in a biodiversity hotspot

Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs) calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover) based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar's plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future

Photodynamically Active Electrospun Fibers for Antibiotic-Free Infection Control

Antimicrobial biomaterials are critical to aid in the regeneration of oral soft tissue and prevent or treat localized bacterial infections. With the rising trend in antibiotic resistance, there is a pressing clinical need for new antimicrobial chemistries and biomaterial design approaches enabling on-demand activation of antibiotic-free antimicrobial functionality following an infection that are environment-friendly, flexible and commercially viable. This study explores the feasibility of integrating a bioresorbable electrospun polymer scaffold with localized antimicrobial photodynamic therapy (aPDT) capability. To enable aPDT, we encapsulated a photosensitizer (PS) in polyester fibers in the PS inert state, so that the antibacterial function would be activated on-demand via a visible light source. Fibrous scaffolds were successfully electrospun from FDA-approved polyesters, either poly(ε-caprolactone (PCL) or poly[(rac-lactide)-co-glycolide] (PLGA), with encapsulated PS (either methylene blue (MB) or erythrosin B (ER)). These were prepared and characterized with regards to their loading efficiency (UV–vis spectroscopy), microarchitecture (SEM, porometry, and BET (Brunauer–Emmett–Teller) analysis), tensile properties, hydrolytic behavior (contact angle, dye release capability, degradability), and aPDT effect. The electrospun fibers achieved an ∼100 wt % loading efficiency of PS, which significantly increased their tensile modulus and reduced their average fiber diameter and pore size with respect to PS-free controls. In vitro, PS release varied between a burst release profile to limited release within 100 h, depending on the selected scaffold formulation, while PLGA scaffolds displayed significant macroscopic shrinkage and fiber merging, following incubation in phosphate buffered saline solution. Exposure of PS-encapsulated PCL fibers to visible light successfully led to at least a 1 log reduction in Escherichia coli viability after 60 min of light exposure, whereas PS-free electrospun controls did not inactive microbes. This study successfully demonstrates the significant potential of PS-encapsulated electrospun fibers as photodynamically active biomaterial for antibiotic-free infection control

THE METABOLISM OF DOPAMINE, NN-DIALKYLATED DOPAMINES AND DERIVATIVES OF THE DOPAMINE AGONIST 2-AMINO-DIHYDROXY-1,2,3,4-TETRAHYDRONAPHTHALENE (ADTN) BY CATECHOL-O-METHYLTRANSFERASE

A variety of dopamine derivatives and analogues were investigated to assess their potential to act as catechol-O-methyltransferase (COMT) substrates using purified, homogeneous pig liver enzyme. This enabled accurate kinetic constants to be determined as opposed to previous in-vivo studies (Rollema et al 1980; Horn et al 1981; Costall et al 1982; Feenstra et al 1983). 2-Amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (A-6,7-DTN) proved to be a far better substrate (Km = 0.082 mM; Vmax = 300 mu mg-1 protein) than its 5,6-dihydroxy isomer (Km = 2.60 mM; Vmax = 113.9 mu mg-1 protein). This result supports evidence suggesting that differences in brain concentration of these isomers are due to their differential susceptibility to O-methylation by COMT (Rollema et al 1980). A similar result was obtained with a series of NN-di-n-alkyl substituted ADTN derivatives: the same pattern of preferential O-methylation of A-6,7-DTN derivatives over the corresponding A-5,6-DTN isomers was observed. However, increasing the length of the alkyl chain increased the susceptibility of both isomers to metabolism by COMT as shown by a decline in Km. An homologous series of NN-di-n-alkylated dopamines showed a similar trend implying that more hydrophobic compounds are better COMT substrates

Synthesis and Fabrication of Surface-Active Microparticles Using a Membrane Emulsion Technique and Conjugation of Model Protein via Strain-Promoted Azide–Alkyne Click Chemistry in Physiological Conditions

The rapid surface immobilization of protein on monodispersed polyester microcarriers is reported. A model protein, functionalized with a dibenzocyclooctyne core, immobilizes on the surface of azide-terminal polycaprolactone microcarriers within 10 min compared to 12 h for other conjugation techniques, and it is conducted in physiological conditions and in the absence of coupling reagents