An evaluation of root phytochemicals derived from Althea officinalis (Marshmallow) and Astragalus membranaceus as potential natural components of UV-protecting dermatological formulations

Open access journalAs lifetime exposure to ultraviolet (UV) radiation has risen, the deleterious effects have also become more apparent. Numerous sunscreen and skincare products have therefore been developed to help reduce the occurrence of sunburn, photo-ageing and skin carcinogenesis. This has stimulated research into identifying new natural sources of effective skin protecting compounds. Alkaline single cell gel electrophoresis (comet assay) was employed to assess aqueous extracts derived from soil or hydroponically glasshouse-grown roots of Althea officinalis (Marshmallow) and Astragalus membranaceus, compared with commercial, field-grown roots. Hydroponically grown root extracts from both plant species were found to significantly reduce UVA-induced DNA damage in cultured human lung and skin fibroblasts, although initial Astragalus experimentation detected some genotoxic effects, indicating that Althea root extracts may be better suited as potential constituents of dermatological formulations. Glasshouse-grown soil and hydroponic Althea root extracts afforded lung fibroblasts with statistically significant protection against UVA irradiation for a greater period of time than the commercial field-grown roots. No significant reduction in DNA damage was observed when total ultraviolet irradiation (including UVB) was employed (data not shown), indicating that the extracted phytochemicals predominantly protected against indirect UVA-induced oxidative stress. Althea phytochemical root extracts may therefore be useful components in dermatological formulations.UK Department of Trade and IndustryUK Department for Environment, Food and Rural AffairsBiotechnology and Biological Sciences Research Council (BBSRC

Density-and trait-mediated effects of a parasite and a predator in a tri-trophic food web

1. Despite growing interest in ecological consequences of parasitism in food webs, relatively little is known about effects of parasites on long-term population dynamics of non-host species or about whether such effects are density- or trait- mediated. 2. We studied a tri-trophic food chain comprised of: (i) a bacterial basal resource (Serratia fonticola), (ii) an intermediate consumer (Paramecium caudatum), (iii) a top predator (Didinium nasutum), and (iv) a parasite of the intermediate consumer (Holospora undulata). A fully-factorial experimental manipulation of predator and parasite presence/absence was combined with analyses of population dynamics, modelling, and analyses of host (Paramecium) morphology and behavior. 3. Predation and parasitism each reduced the abundance of the intermediate consumer (Paramecium), and parasitism indirectly reduced the abundance of the basal resource (Serratia). However, in combination, predation and parasitism had non-additive effects on the abundance of the intermediate consumer, as well as on that of the basal resource. In both cases, the negative effect of parasitism seemed to be effaced by predation. 4. Infection of the intermediate consumer reduced predator abundance. Modelling and additional experimentation revealed that this was most likely due to parasite reduction of intermediate host abundance (a density-mediated effect), as opposed to changes in predator functional or numerical response. 5. Parasitism altered morphological and behavioural traits, by reducing host cell length and increasing the swimming speed of cells with moderate parasite loads. Additional tests showed no significant difference in Didinium feeding rate on infected and uninfected hosts, suggesting that the combination of these modifications does not affect host vulnerability to predation. However, estimated rates of encounter with Serratia based on these modifications were higher for infected Paramecium than for uninfected Paramecium. 6. A mixture of density-mediated and trait-mediated indirect effects of parasitism on non- host species creates rich and complex possibilities for effects of parasites in food webs that should be included in assessments of possible impacts of parasite eradication or introduction

The role of mTOR-mediated signals during haemopoiesis and lineage commitment

The serine/threonine protein kinase mechanistic target of rapamycin (mTOR) has been implicated in the regulation of an array of cellular functions including protein and lipid synthesis, proliferation, cell size and survival. Here, we describe the role of mTOR during haemopoiesis within the context of mTORC1 and mTORC2, the distinct complexes in which it functions. The use of conditional transgenic mouse models specifically targeting individual mTOR signalling components, together with selective inhibitors, have generated a significant body of research emphasising the critical roles played by mTOR, and individual mTOR complexes, in haemopoietic lineage commitment and development. This review will describe the profound role of mTOR in embryogenesis and haemopoiesis, underscoring the importance of mTORC1 at the early stages of haemopoietic cell development, through modulation of stem cell potentiation and self-renewal, and erythroid and B cell lineage commitment. Furthermore, the relatively discrete role of mTORC2 in haemopoiesis will be explored during T cell development and B cell maturation. Collectively, this review aims to highlight the functional diversity of mTOR signalling and underline the importance of this pathway in haemopoiesis

Endocrine regulation of placental phenotype

Hormones have an important role in regulating fetal development. They act as environmental signals and integrate tissue growth and differentiation with relation to nutrient availability. While hormones control the developmental fate of resources available to the fetus, the actual supply of nutrients and oxygen to the fetus depends on the placenta. However, much less is known about the role of hormones in regulating placental development, even though the placenta has a wide range of hormone receptors and produces hormones itself from early in gestation. The placenta is, therefore, exposed to hormones by autocrine, paracrine and endocrine mechanisms throughout its lifespan. It is known to adapt its phenotype in response to environmental cues and fetal demand signals, particularly when there is a disparity between the fetal genetic drive for growth and the nutrient supply. These adaptive responses help to maintain fetal growth during adverse conditions and are likely to depend, at least in part, on the hormonal milieu. This review examines the endocrine regulation of placental phenotype with particular emphasis on the glucocorticoid hormones. It focuses on the availability of placental hormone receptors and on the effects of hormones on the morphology, transport capacity and endocrine function of the placenta.We would like to thank the many members of the Department of Physiology, Development and Neuroscience who have contributed to discussions and helped with our own studies cited here. We are also grateful for financial support from the BBSRC (BB/I011773/1), Horserace Betting Levy Board (VET/PRJ/726 and 736), the Wellcome Trust 084804/2/08/Z and the Centre for Trophoblast Research at the University of Cambridge.This is the accepted manuscript. The final version is available from Elsevier at http://dx.doi.org/10.1016/j.placenta.2014.11.01

"He's going to be a doctor in August": A narrative interview study of medical students' and their educators' experiences of aligned and misaligned assistantships

Objective To explore final-year students’ and clinical supervisors’ experiences of alignment and misalignment with future Foundation Year 1 (F1) posts in an assistantship programme in the UK. Setting Assistantships are clinical placements in which students assist junior doctors by undertaking similar duties under supervision. Models of assistantship programmes vary across curricula. Some actively seek to align with students’ initial postgraduate F1 post. To date, no research has examined the implications of this association for teaching and learning. Qualitative individual and group narrative interviews were conducted with students and supervisors of 2 Welsh medical schools to address: RQ1: How do students and supervisors understand the purpose of the longitudinal assistantship? RQ2: Does alignment/misalignment of the assistantship with students’ initial F1 post influence students’ and supervisors’ teaching and learning experiences? Audio-recordings of interviews were transcribed, participants anonymised and framework analysis was used. Participants A convenience sample of 4 participant groups comprised (1) final-year medical students whose assistantship and F1 post were aligned (n=27), (2) final-year medical students whose assistantship and F1 post were misaligned (n=18) and (3) supervisors (n=10, junior doctors; n=11, consultants). Results All participant groups highlighted increased student confidence in undertaking the duties of an F1 doctor arising from their assistantship period. Learning transferable skills was also highlighted. Many students considered themselves to be team members, ‘learning the trade’ as they shadowed their F1. Opportunities for caring for acutely unwell patients were scarce. The evidence shows enhanced engagement for students aligned to their first F1 post with greater opportunities for workplace acclimatisation. Those who were misaligned were perceived as being disadvantaged. Conclusions Our findings suggest that alignment with students’ first F1 post enhances the assistantship experience. Further longitudinal assessment is required to examine whether and how this translates into improvement

Evaluating Total Environmental Impact for a Computing Infrastructure

In this paper we outline the results of a project to evaluate the total climate/carbon impact of a digital research infrastructure for a defined snapshot period. We outline the carbon model used to calculate the impact and the data collected to quantify that impact for a defined set of resources. We discuss the variation in potential impact across both the active and embodied carbon for computing hardware and produce a range of estimates on the amount of carbon equivalent climate impact for the snapshot period

Reduced physical activity and increased sedentary behaviour: The damage on young people during the COVID-19 pandemic

Health childhood development is fostered through movement behaviours, including sufficient physical activity (Moore et al. 2020). This article reviews some of the recently published global studies that have examined the impact of COVID-19 on children’s physical activity and sedentary behaviours, the majority of which have indicated that children’s physical activity behaviours have lessened significantly during these times, while their sedentary behaviours have risen significantly. The authors then go on to make some suggestions of ways in which to encourage and foster physical activity for both children and their families, for example by showing people different ways of staying active, and offering other opportunities for physical activity, as well as ensuring the feeling of staying safe and protected