Lycopodiella inundata: insights into plant-fungal associations in early vascular plants

Recent studies have revealed that extant basal vascular plants associate with a wide range of Mucoromycotina and/or Glomeromycota fungi, paralleling the same in non-vascular liverworts and hornworts. This dispels the long-held paradigm that these early diverging lineages harbour Glomeromycota exclusively. Endophytes belonging to both fungal lineages have also been reported, for the first time, in a Devonian plant (Horneophyton ligneri). Together these discoveries point to much more diverse plant-fungus interactions in early vascular plants than previously assumed, however our understanding of these remains limited. In order to gain further insights into these key partnerships, especially those involving the early diverging Mucoromycotina, we are developing the lycophyte Lycopodiella inundata as an experimental system. L. inundata sporophytes have been shown to harbour solely Mucoromycotina fungi but equally fundamental, the identity of its gametophyte endophyte remains unknown. Using molecular and cytological approaches, we confirm that young L. inundata sporophytes are colonized exclusively by Mucoromycotina and show that the cytology of colonisation - consisting of both inter- and intracellular phases - closely resembles that in Haplomitriopsida liverwort-Mucoromycotina partnerships and the corm of H. ligneri. Our current isolation, resynthesis and molecular studies will provide further insights into both host and fungi specificity.This is a poster presented The Rhynie Chert – our earliest terrestrial ecosystem revisited. For more information on the conference consult the above links

Delayed bowel perforation following suprapubic catheter insertion

BACKGROUND: Complications of suprapubic catheter insertion are rare but can be significant. We describe an unusual complication of a delayed bowel perforation following suprapubic catheter insertion. CASE PRESENTATION: A gentleman presented with features of peritonitis and feculent discharge along a suprapubic catheter two months after insertion of the catheter. CONCLUSION: Bowel perforation is the most feared complication of suprapubic catheter insertion especially in patients with lower abdominal scar. The risk may be reduced with the use of ultrasound scan guidance

Functional regeneration of tissue engineered skeletal muscle in vitro is dependent on the inclusion of basement membrane proteins

Skeletal muscle has a high regenerative capacity, injuries trigger a regenerative program which restores tissue function to a level indistinguishable to the pre-injury state. However, in some cases where significant trauma occurs, such as injuries seen in military populations, the regenerative process is overwhelmed and cannot restore full function. Limited clinical interventions exist which can be used to promote regeneration and prevent the formation of non-regenerative defects following severe skeletal muscle trauma. Robust and reproducible techniques for modelling complex tissue responses are essential to promote the discovery of effective clinical interventions. Tissue engineering has been highlighted as an alternative method, allowing the generation of three-dimensional in vivo like tissues without laboratory animals. Reducing the requirement for animal models promotes rapid screening of potential clinical interventions, as these models are more easily manipulated genetically and pharmacologically and reduce the associated cost and complexity, whilst increasing access to models for laboratories without animal facilities. In this study an in vitro chemical injury using barium chloride is validated using the C2C12 myoblast cell line, and is shown to selectively remove multinucleated myotubes, whilst retaining a regenerative mononuclear cell population. Monolayer cultures showed limited regenerative capacity, with basement membrane supplementation or extended regenerative time incapable of improving the regenerative response. Conversely tissue engineered skeletal muscles, supplemented with basement membrane proteins, showed full functional regeneration, and a broader in vivo like inflammatory response. This work outlines a freely available and open access methodology to produce a cell line-based tissue engineered model of skeletal muscle regeneration

A mycorrhizal revolution.

It has long been postulated that symbiotic fungi facilitated plant migrations onto land through enhancing the scavenging of mineral nutrients and exchanging these for photosynthetically fixed organic carbon. Today, land plant-fungal symbioses are both widespread and diverse. Recent discoveries show that a variety of potential fungal associates were likely available to the earliest land plants, and that these early partnerships were probably affected by changing atmospheric CO2 concentrations. Here, we evaluate current hypotheses and knowledge gaps regarding early plant-fungal partnerships in the context of newly discovered fungal mutualists of early and more recently evolved land plants and the rapidly changing views on the roles of plant-fungal symbioses in the evolution and ecology of the terrestrial biosphere

Physiological and pathophysiological concentrations of fatty acids induce lipid droplet accumulation and impair functional performance of tissue engineered skeletal muscle

Fatty acids (FA) exert physiological and pathophysiological effects leading to changes in skeletal muscle metabolism and function, however, in vitro models to investigate these changes are limited. These experiments sought to establish the effects of physiological and pathophysiological concentrations of exogenous FA upon the function of tissue engineered skeletal muscle (TESkM). Cultured initially for 14 days, C2C12 TESkM was exposed to FA‐free bovine serum albumin alone or conjugated to a FA mixture (oleic, palmitic, linoleic, and α‐linoleic acids [OPLA] [ratio 45:30:24:1%]) at different concentrations (200 or 800 µM) for an additional 4 days. Subsequently, TESkM morphology, functional capacity, gene expression and insulin signaling were analyzed. There was a dose response increase in the number and size of lipid droplets within the TESkM (p < .05). Exposure to exogenous FA increased the messenger RNA expression of genes involved in lipid storage (perilipin 2 [p < .05]) and metabolism (pyruvate dehydrogenase lipoamide kinase isozyme 4 [p < .01]) in a dose dependent manner. TESkM force production was reduced (tetanic and single twitch) (p < .05) and increases in transcription of type I slow twitch fiber isoform, myosin heavy chain 7, were observed when cultured with 200 µM OPLA compared to control (p < .01). Four days of OPLA exposure results in lipid accumulation in TESkM which in turn results in changes in muscle function and metabolism; thus, providing insight ito the functional and mechanistic changes of TESkM in response to exogenous FA.</div

Mucoromycotina fine root endophyte fungi form nutritional mutualisms with vascular plants

Fungi and plants have engaged in intimate symbioses that are globally widespread and have driven terrestrial biogeochemical processes since plant terrestrialization >500 million years ago. Recently, hitherto unknown nutritional mutualisms involving ancient lineages of fungi and nonvascular plants have been discovered, although their extent and functional significance in vascular plants remain uncertain. Here, we provide evidence of carbon-for-nitrogen exchange between an early-diverging vascular plant (Lycopodiella inundata) and Mucoromycotina (Endogonales) fine root endophyte fungi. Furthermore, we demonstrate that the same fungal symbionts colonize neighboring nonvascular and flowering plants. These findings fundamentally change our understanding of the physiology, interrelationships, and ecology of underground plant–fungal symbioses in modern terrestrial ecosystems by revealing the nutritional role of Mucoromycotina fungal symbionts in vascular plants

Future challenges of occupational safety and health policy-making in the UK

Understanding the changing landscape of occupational safety and health (OSH) regulation and standards and its implications are of central importance for ensuring that OSH outcomes are not compromised and the needs of different types of organizations are met. It is also important for developing appropriate strategies to anticipate and deal with future challenges for OSH policy-making. This paper draws on findings from two qualitative studies with key OSH stakeholders in the UK that were conducted as part of a research programme funded the Institution of Occupational Safety & Health. The aim of the first study was to elicit the views of key stakeholders on changes in the current OSH landscape so as to understand the nature and implications of these changes. The second study explored stakeholder perspectives on how to secure the optimal OSH landscape in the UK by addressing key future challenges for OSH policy-making

Mechanistic studies on δ-aminolevulinic acid uptake and efflux in a mammary adenocarcinoma cell line

δ-aminolevulinic acid (ALA) is the precursor in the biosynthesis of porphyrins. The knowledge of both the regulation of ALA entrance and efflux from the cells and the control of porphyrin biosynthesis is essential to improve ALA-mediated photodynamic therapy. In this work, we studied the regulation of ALA uptake and efflux by endogenously accumulated ALA and/or porphyrins in murine mammary adenocarcinoma cells. Under our set of conditions, the haem synthesis inhibitor succinyl acetone completely prevented porphobilinogen and porphyrin synthesis from ALA, and led to an increase in the intracellular ALA pool. However, neither intracellular ALA nor porphyrin pools regulate ALA uptake or efflux during the first 15 min of the process. Based on temperature dependence data, ALA but not γ-aminobutyric acid (GABA) efflux is mediated by a diffusion mechanism. Moreover, the addition of extracellular GABA not only did not influence the rate of ALA efflux but on the contrary it affected ALA uptake, showing the contribution of a saturable mechanism for the uptake, but not for the efflux of ALA from the cells. © 2003 Cancer Research UK.Fil:Correa García, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Casas, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Perotti, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Batlle, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Bermúdez Moretti, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina