A temperate river estuary is a sink for methanotrophs adapted to extremes of pH, temperature and salinity

River Tyne (UK) estuarine sediments harbour a genetically and functionally diverse community of methane-oxidizing bacteria (methanotrophs), the composition and activity of which were directly influenced by imposed environmental conditions (pH, salinity, temperature) that extended far beyond those found in situ. In aerobic sediment slurries methane oxidation rates were monitored together with the diversity of a functional gene marker for methanotrophs (pmoA). Under near in situ conditions (4-30°C, pH 6-8, 1-15gl-1 NaCl), communities were enriched by sequences affiliated with Methylobacter and Methylomonas spp. and specifically a Methylobacter psychrophilus-related species at 4-21°C. More extreme conditions, namely high temperatures ≥40°C, high ≥9 and low ≤5 pH, and high salinities ≥35gl-1 selected for putative thermophiles (Methylocaldum), acidophiles (Methylosoma) and haloalkaliphiles (Methylomicrobium). The presence of these extreme methanotrophs (unlikely to be part of the active community in situ) indicates passive dispersal from surrounding environments into the estuary

Functional testing of topical skin formulations using an optimised ex vivo skin organ culture model.

A number of equivalent-skin models are available for investigation of the ex vivo effect of topical application of drugs and cosmaceuticals onto skin, however many have their drawbacks. With the March 2013 ban on animal models for cosmetic testing of products or ingredients for sale in the EU, their utility for testing toxicity and effect on skin becomes more relevant. The aim of this study was to demonstrate proof of principle that altered expression of key gene and protein markers could be quantified in an optimised whole tissue biopsy culture model. Topical formulations containing green tea catechins (GTC) were investigated in a skin biopsy culture model (n = 11). Punch biopsies were harvested at 3, 7 and 10 days, and analysed using qRT-PCR, histology and HPLC to determine gene and protein expression, and transdermal delivery of compounds of interest. Reduced gene expression of α-SMA, fibronectin, mast cell tryptase, mast cell chymase, TGF-β1, CTGF and PAI-1 was observed after 7 and 10 days compared with treated controls (p < 0.05). Histological analysis indicated a reduction in mast cell tryptase and chymase positive cell numbers in treated biopsies compared with untreated controls at day 7 and day 10 (p < 0.05). Determination of transdermal uptake indicated that GTCs were detected in the biopsies. This model could be adapted to study a range of different topical formulations in both normal and diseased skin, negating the requirement for animal models in this context, prior to study in a clinical trial environment

A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring

Wound healing after dermal injury is an imperfect process, inevitably leading to scar formation as the skin re-establishes its integrity. The resulting scars have different characteristics to normal skin, ranging from fine-line asymptomatic scars to problematic scarring including hypertrophic and keloid scars. Scars appear as a different colour to the surrounding skin and can be flat, stretched, depressed or raised, manifesting a range of symptoms including inflammation, erythema, dryness and pruritus, which can result in significant psychosocial impact on patients and their quality of life. In this paper, a comprehensive literature review coupled with an analysis of levels of evidence (LOE) for each published treatment type was conducted. Topical treatments identified include imiquimod, mitomycin C and plant extracts such as onion extract, green tea, Aloe vera, vitamin E and D, applied to healing wounds, mature scar tissue or fibrotic scars following revision surgery, or in combination with other more established treatments such as steroid injections and silicone. In total, 39 articles were included, involving 1703 patients. There was limited clinical evidence to support their efficacy; the majority of articles (n = 23) were ranked as category 4 LOE, being of limited quality with individual flaws, including low patient numbers, poor randomisation, blinding, and short follow-up periods. As trials were performed in different settings, they were difficult to compare. In conclusion, there is an unmet clinical need for effective solutions to skin scarring, more robust long-term randomised trials and a consensus on a standardised treatment regime to address all aspects of scarring

The bacteriohopanepolyol inventory of novel aerobic methane oxidising bacteria reveals new biomarker signatures of aerobic methanotrophy in marine systems

Aerobic methane oxidation (AMO) is one of the primary biologic pathways regulating the amount of methane (CH4) released into the environment. AMO acts as a sink of CH4, converting it into carbon dioxide before it reaches the atmosphere. It is of interest for (paleo)climate and carbon cycling studies to identify lipid biomarkers that can be used to trace AMO events, especially at times when the role of methane in the carbon cycle was more pronounced than today. AMO bacteria are known to synthesise bacteriohopanepolyol (BHP) lipids. Preliminary evidence pointed towards 35-aminobacteriohopane-30,31,32,33,34-pentol (aminopentol) being a characteristic biomarker for Type I methanotrophs. Here, the BHP compositions were examined for species of the recently described novel Type I methanotroph bacterial genera Methylomarinum and Methylomarinovum, as well as for a novel species of a Type I Methylomicrobium. Aminopentol was the most abundant BHP only in Methylomarinovum caldicuralii, while Methylomicrobium did not produce aminopentol at all. In addition to the expected regular aminotriol and aminotetrol BHPs, novel structures tentatively identified as methylcarbamate lipids related to C-35 amino-BHPs (MCBHPs) were found to be synthesised in significant amounts by some AMO cultures. Subsequently, sediments and authigenic carbonates from methane-influenced marine environments were analysed. Most samples also did not contain significant amounts of aminopentol, indicating that aminopentol is not a useful biomarker for marine aerobic methanotophic bacteria. However, the BHP composition of the marine samples do point toward the novel MC-BHPs components being potential new biomarkers for AMO

Strategies for Inhibiting Advanced Glycation Endproduct (Age) Induced Vascular Calcification in a Smooth Muscle Cell Culture Model

Vascular calcification is implicated in a range of cardiovascular disease mechanisms, leading to an associated increase in morbidity and mortality. One such trigger are advanced glycation endproducts (AGEs), the tissue accumulation of which increases with age and is more prevalent in diabetic subjects due to oxidative stress and poor glycaemic control. The aim of this study was to investigate the osteogenic potential of AGEs and elucidate mechanisms of inhibiting these processes in a smooth muscle cell (SMC) culture model. Osteogenic differentiation of SMCs was induced using β-glycerophosphate (β-GP), carboxymethyllysine (CML), carboxyethyllysine (CEL) methylglyoxal (MGO) and glycated low density lipoprotein (gly-LDL). The cells were subsequently treated with aminoguanidine (AG), an inhibitor of AGE formation, and novel glycomimetic compounds in order to determine their anti-calcification potential in vitro using qPCR, ELISA, Alkaline phosphatase (ALP) activity and Alizarin red staining. Gly-LDL (10 µg/ml) and CML (2.5nM) increased the level of calcification observed compared to the β-GP (5 mM) positive control after 21 days (p < 0.05), with gly-LDL induced calcification apparent after 14 days. Both AG (250 µM) and the novel glycomimetic compounds reduced the level of mineralisation observed at 21 days compared with osteogenic treatments (p < 0.05). CEL (2.5 nM) and MGO (0.1 mM) both induced calcification, however mineralization was not as extensive as with β-GP. When compared to the structure of CML, the side-chain of CEL contains an extra methyl group, suggesting this group impacts RAGE receptor binding. It was also shown that β-GP combined with increased glucose concentration induced more extensive calcification unlike low glucose levels and β-GP alone. ALP activity, when stimulated with β-GP, CML and gly-LDL was greater at day 4 than at day 7, with AG reducing ALP activity measurements at day 4. Gly-LDL increases gene expression of OCN at day 4 compared with β-GP and CML, however this was reduced at day 7, corresponding with an increased expression of OPN and OPG. NOTCH-3 gene expression was also reduced at day 7. Gene expression of OPN, OPG and NOTCH-3 were reduced at both day 4 and day 7 compared with osteogenic treatments (β-GP, CML and gly-LDL). In summary, we conclude that gly-LDL and CML are potent inducers of calcification compared with β-GP, and that their osteogenic potential can be modulated by both AG and novel glycomimetic compounds

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Stepping across the line: Information sharing, truth-telling and the role of the personal carer in the Australian Nursing Home

The author draws on an Australian study using multiple qualitative methods to investigate truth telling in aged care. Thematic analysis of data from five nursing homes involving 23 personal care assistants revealed participants’ role understanding as influencing their perceptions about truth telling in practice. Five themes emerged: role as the happy comfort carer, division of labor, division of disclosure, role tension and frustration, and managing the division of disclosure. Role emphasis on comfort and happiness and a dominant perception that telling the truth can cause harm mean that disclosure will be withheld, edited, or partial. Participants’ role understanding divides labor and disclosure responsibility between the personal carer and registered nurse. Personal carers’ strategies for managing the division of disclosure include game playing, obfuscation, lying (denial), and the use of nonverbals. These perceptions about personal carer role, information sharing, and truth telling are paramount for understanding and improving nursing home eldercare

Neutrinos in a gravitational background: a test for the universality of the gravitational interaction

In this work we propose an extended formulation for the interaction between neutrinos and gravitational fields. It is based on the parametrized post-Newtonian aproach, and includes a violation of the universality of the gravitational interaction which is non diagonal in the weak flavor space. We find new effects that are not considered in the standard scenario for violation of the equivalence principle. They are of the same order as the effects produced by the Newtonian potential, but they are highly directional dependent and could provide a very clean test of that violation. Phenomenological consequences are briefly discussed.Comment: 18 pages, revtex, no figure