Microvesicles as vehicles for tissue regeneration: Changing of the guards

Purpose of Review: Microvesicles (MVs) have been recognised as mediators of stem cell function, enabling and guiding their regenerative effects. Recent Findings: MVs constitute one unique size class of extracellular vesicles (EVs) directly shed from the cell plasma membrane. They facilitate cell-to-cell communication via intercellular transfer of proteins, mRNA and microRNA (miRNA). MVs derived from stem cells, or stem cell regulatory cell types, have proven roles in tissue regeneration and repair processes. Their role in the maintenance of healthy tissue function throughout the life course and thus in age related health span remains to be elucidated. Summary: Understanding the biogenesis and mechanisms of action of MVs may enable the development of cell-free therapeutics capable of assisting in tissue maintenance and repair for a variety of age-related degenerative diseases. This review critically evaluates recent work published in this area and highlights important new findings demonstrating the use of MVs in tissue regeneration

Aristotelian rationality of animals: phantasia as a commonality of human and animal cognitive processes

This dissertation investigates Aristotle’s theory of phantasia as a cognitive ability, in terms of which mental content is available to the mind of rational beings. The focus is on Catherine Osborne’s extension of phantasia to nonhuman animals in order to allow for and explain non-human animal behaviour in terms of a rational paradigm, which de-emphasises, and does not rely on, linguistic ability. This paradigm for understanding animal behaviour as rational supports, and is supported by, modern theories of cognitive ethology, and argues for the ability of animals to share in conceptual thought. The recognition of rationality in animals by means of this paradigm bears ethical consequences for the treatment of animals.Classics and Modern European LanguagesM.A. (Classical Studies

Sensory System Responses to Human-Induced Environmental Change

Sensory input to the central nervous system is the primary means by which animals respond to variation in their physical and biological environments. It is well established that key threats such as habitat destruction, the introduction of non-native species, and climate change are imposing significant pressures on natural ecosystems, yet surprisingly few studies have examined how these threats impact the senses or determine species' responses to environmental change. This review focuses on how anthropogenic impacts on aquatic ecosystems can have a detrimental effect on the sensory systems of aquatic organisms and how these modalities can act to influence genetic and non-genetic (e.g., developmental) responses to environmental change, which in turn can cause knock-on effects in a range of other biological systems. Species often exhibit unique sensory specializations that are suited to their behavioral requirements; at present it is unclear whether and how sensory systems have the capacity to respond to environmental change through genetic adaptation and/or sensory plasticity, and on what timescale this might occur. Sensory systems lie at the forefront of how various species respond to environmental perturbation. As such, determining the important role they play in determining fitness is critical for understanding the effects of external processes such as habitat degradation and climate change. Given the current consensus that human impacts and environmental changes are potentially highly detrimental to the delicate balance of the biome, knowing how organisms respond, and to what degree adaptation is physiologically and behaviorally limited, warrants urgent attention

Visual pigments in a living fossil, the Australian lungfish Neoceratodus forsteri

Background. One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. Results. Here we identify and characterise five visual pigments (rh1, rh2, lws, sws1 and sws2) expressed in the retina of N. forsteri. Phylogenetic analysis of the molecular evolution of lungfish and other vertebrate visual pigment genes indicates a closer relationship between lungfish and amphibian pigments than to pigments in teleost fishes. However, the relationship between lungfish, the coelacanth and tetrapods could not be absolutely determined from opsin phylogeny, supporting an unresolved trichotomy between the three groups. Conclusion. The presence of four cone pigments in Australian lungfish suggests that the earliest tetrapods would have had a colorful view of their terrestrial environment

Crop response to amelioration of agricultural soils are mediated by contraint combinations and soil type

Over the past decade alternative strategic deep tillage approaches have been developed to complement more established soil amelioration methods. Strategic tillage takes the form of a one-off or occasional intervention, implemented to overcome a number of soil and biotic constraints. Deep ripping can effectively remove subsoil hardpans and potentially delve up some subsoil to the surface depending on tine design. Deep soil mixing, using rotary spaders or large disc ploughs, can mix and incorporate topsoil and amendments deeper into the soil profile and reduce topsoil repellence. Soil inversion, using mouldboard, square or one-way disc ploughs, can bury surface-applied amendments, as well as repellent topsoil and weed seeds. While these techniques principally address soil constraints, some also improve weed control and reduce frost damage

Crop Response to Amelioration of Agricultural Soils are Mediated by Constraint Combinations and Soil Type

Over the past decade alternative strategic deep tillage approaches have been developed to complement more established soil amelioration methods. Strategic tillage takes the form of a one-off or occasional intervention, implemented to overcome a number of soil and biotic constraints

Developmental dynamics of cone photoreceptors in the eel

Background: Many fish alter their expressed visual pigments during development. The number of retinal opsins expressed and their type is normally related to the environment in which they live. Eels are known to change the expression of their rod opsins as they mature, but might they also change the expression of their cone opsins?Results: The Rh2 and Sws2 opsin sequences from the European Eel were isolated, sequenced and expressed in vitro for an accurate measurement of their lambda(max) values. In situ hybridisation revealed that glass eels express only rh2 opsin in their cone photoreceptors, while larger yellow eels continue to express rh2 opsin in the majority of their cones, but also have <5% of cones which express sws2 opsin. Silver eels showed the same expression pattern as the larger yellow eels. This observation was confirmed by qPCR (quantitative polymerase chain reaction).Conclusions: Larger yellow and silver European eels express two different cone opsins, rh2 and sws2. This work demonstrates that only the Rh2 cone opsin is present in younger fish (smaller yellow and glass), the sws2 opsin being expressed additionally only by older fish and only in <5% of cone cells