‘Inverted’ analogs of the antibiotic gramicidin S with an improved biological profile

A series of gramicidin S derivatives 4–15 are presented that have four ornithine residues as polar protonated side chains and two central hydrophobic amino acids with unaltered turn regions. These peptides were screened against human erthrocytes and our standard panel of Gram negative- and Gram positive bacteria, including four MRSA strains. Based on the antibacterial- and hemolytic data, peptides 13 and 14 have an improved biological profile compared to the clinically applied topical antibiotic gramicidin S.     

The Hypothetical Protein ‘All4779’, and Not the Annotated ‘Alr0088’ and ‘Alr7579’ Proteins,Is the Major Typical Single-Stranded DNA Binding Protein of the Cyanobacterium,Anabaena sp. PCC7120

Single-stranded DNA binding (SSB) proteins are essential for all DNA-dependent cellular processes. Typical SSB proteins have an N-terminal Oligonucleotide-Binding (OB) fold, a Proline/Glycine rich region, followed by a C-terminal acidic tail. In the genome of the heterocystous nitrogen-fixing cyanobacterium, Anabaena sp. strain PCC7120, alr0088 and alr7579 are annotated as coding for SSB, but are truncated and have only the OB-fold. In silico analysis of whole genome of Anabaena sp. strain PCC7120 revealed the presence of another ORF ‘all4779’, annotated as a hypothetical protein, but having an N-terminal OB-fold, a P/G-rich region and a C-terminal acidic tail. Biochemical characterisation of all three purified recombinant proteins revealed that they exist either as monomer or dimer and bind ssDNA, but differently. The All4779 bound ssDNA in two binding modes i.e. (All4779)₃₅ and (All4779)₆₆ depending on salt concentration and with a binding affinity similar to that of Escherichia coli SSB. On the other hand, Alr0088 bound in a single binding mode of 50-mer and Alr7579 only to large stretches of ssDNA, suggesting that All4779, in all likelihood, is the major typical bacterial SSB in Anabaena. Overexpression of All4779 in Anabaena sp. strain PCC7120 led to enhancement of tolerance to DNA-damaging stresses, such as γ-rays, UV-irradiation, desiccation and mitomycinC exposure. The tolerance appears to be a consequence of reduced DNA damage or efficient DNA repair due to increased availability of All4779. The ORF all4779 is proposed to be re-annotated as Anabaena ssb gene.     

Parkinson’s Protein α-Synuclein Binds Efficiently and with a Novel Conformation to Two Natural Membrane Mimics

Binding of human α-Synuclein, a protein associated with Parkinson’s disease, to natural membranes is thought to be crucial in relation to its pathological and physiological function. Here the binding of αS to small unilamellar vesicles mimicking the inner mitochondrial and the neuronal plasma membrane is studied in situ by continuous wave and pulsed electron paramagnetic resonance. Local binding information of αS spin labeled by MTSL at positions 56 and 69 respectively shows that also helix 2 (residues 50–100) binds firmly to both membranes. By double electron-electron resonance (DEER) on the mutant spin labeled at positions 27 and 56 (αS 27/56) a new conformation on the membrane is found with a distance of 3.6 nm/ 3.7 nm between residues 27 and 56. In view of the low negative charge density of these membranes, the strong interaction is surprising, emphasizing that function and pathology of αS could involve synaptic vesicles and mitochondria.     

Natural fermentation of soybean (glycine max) with added salt for ‘soy-daddawa’ production

Microbial growth, pH and titratable acidity decreased with increasing NaCl concentration during the fermentation of soybeans. NaCl at 1% (w/w) in the fermenting mash improved the organoleptic quality of soy-daddawa.The author is with the Department of Microbiology, Obafemi Awolowo University, lle-lfe, Nigeria.     

Can the stress protein response be controlled by ‘membrane-lipid therapy’?

In addition to high temperature, other stresses and clinical conditions such as cancer and diabetes can lead to the alteration of heat-shock protein (HSP) levels in cells. Moreover, HSPs can associate with either specific lipids or with areas of special membrane topology (such as lipid rafts), and changes in the physical state of cellular membranes can alter hsp gene expression. We propose that membrane microheterogeneity is important for regulating the HSP response. In support of this hypothesis, when particular membrane intercalating compounds are used to alter membrane properties, the simultaneous normalization of dysregulated expression of HSPs causes beneficial responses to disease states. Therefore, these compounds (such as hydroxylamine derivatives) have the potential to become a new class of pharmaceuticals for use in 'membrane-lipid therapy'.     

Natural climate solutions versus bioenergy: Can carbon benefits of natural succession compete with bioenergy from short rotation coppice?

Short rotation plantations are often considered as holding vast potentials for future global bioenergy supply. In contrast to raising biomass harvests in forests, purpose‐grown biomass does not interfere with forest carbon (C) stocks. Provided that agricultural land can be diverted from food and feed production without impairing food security, energy plantations on current agricultural land appear as a beneficial option in terms of renewable, climate‐friendly energy supply. However, instead of supporting energy plantations, land could also be devoted to natural succession. It then acts as a long‐term C sink which also results in C benefits. We here compare the sink strength of natural succession on arable land with the C saving effects of bioenergy from plantations. Using geographically explicit data on global cropland distribution among climate and ecological zones, regionally specific C accumulation rates are calculated with IPCC default methods and values. C savings from bioenergy are given for a range of displacement factors (DFs), acknowledging the varying efficiency of bioenergy routes and technologies in fossil fuel displacement. A uniform spatial pattern is assumed for succession and bioenergy plantations, and the considered timeframes range from 20 to 100 years. For many parameter settings—in particular, longer timeframes and high DFs—bioenergy yields higher cumulative C savings than natural succession. Still, if woody biomass displaces liquid transport fuels or natural gas‐based electricity generation, natural succession is competitive or even superior for timeframes of 20–50 years. This finding has strong implications with climate and environmental policies: Freeing land for natural succession is a worthwhile low‐cost natural climate solution that has many co‐benefits for biodiversity and other ecosystem services. A considerable risk, however, is C stock losses (i.e., emissions) due to disturbances or land conversion at a later time.     

‘Canis empathicus’? A proposal on dogs' capacity to empathize with humans

Empathy has long attracted the attention of philosophers and psychologists, and more recently, of evolutionary biologists. Interestingly, studies suggest that empathy is a phylogenetically continuous phenomenon, ranging across animals from automatic emotional activation in response to the emotions of others, to perspective-taking that becomes increasingly complex with increasing brain size. Although suggestions have been made that the domestic dog may have the capacity to empathize with humans, no discussion has yet addressed the topic, nor have experimental routes been proposed to further explore the level of emotional and cognitive processing underlying dogs' seemingly empathic behaviour towards humans. In this opinion piece, we begin by contextualizing our topic of interest within the larger body of literature on empathy. Thereafter we: (i) outline the reasons for why we believe dogs may be capable of empathizing with humans, perhaps even at some level beyond emotional contagion; (ii) review available evidence both pro and against our opinion; and (iii) propose routes for future studies to accurately address the topic. Also, we consider the use of dogs to further explore open questions regarding empathy in humans.     

iPAD or PADi — ‘tablets’ with therapeutic disease potential?

The PAD enzymes.

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Can optimality models and an ‘optimality research program’ help us understand some plant–fungal relationships?

In this paper we suggest that the field of fungal ecology may benefit from the use of optimality models in the context of an ‘optimality research program’ (ORP). An ORP is a research program in the sense of modern philosopher of science Lakatos' [1978. The Methodology of Scientific Research Programmes: philosophical papers, vol. 1. Cambridge University Press, Cambridge] seminal work. An optimality research program has a lengthy history and record of success in the field of behavioural ecology, but has been seldom employed in fungal ecology. We discuss the ORP and provide some examples of how optimality models may be useful in fungal ecology. We suggest that such an approach may benefit experimental fungal ecologists by: providing a framework for organizing knowledge; generating hypotheses; helping in the planning of experiments; aiding in the interpretation of results; and directing the next steps of an experimental research program. We illustrate these benefits by sketching out how an ORP might be used to answer some fundamental questions about the interactions between host plants and arbuscular mycorrhizal fungi.     

Can Schools Support HIV/AIDS-Affected Children? Exploring the ‘Ethic of Care’ amongst Rural Zimbabwean Teachers

How realistic is the international policy emphasis on schools ‘substituting for families’ of HIV/AIDS-affected children? We explore the ethic of care in Zimbabwean schools to highlight the poor fit between the western caring schools literature and daily realities of schools in different material and cultural contexts. Interviews and focus groups were conducted with 44 teachers and 55 community members, analysed in light of a companion study of HIV/AIDS-affected pupils’ own accounts of their care-related experiences. We conceptualise schools as spaces of engagement between groups with diverse needs and interests (teachers, pupils and surrounding community members), with attention to the pathways through which extreme adversity impacts on those institutional contexts and social identifications central to giving and receiving care. Whilst teachers were aware of how they might support children, they seldom put these ideas into action. Multiple factors undermined caring teacher-pupil relationships in wider contexts of poverty and political uncertainty: loss of morale from low salaries and falling professional status; the inability of teachers to solve HIV/AIDS-related problems in their own lives; the role of stigma in deterring HIV/AIDS-affected children from disclosing their situations to teachers; authoritarian teacher-learner relations and harsh punishments fuelling pupil fear of teachers; and lack of trust in the wider community. These factors undermined: teacher confidence in their skills and capacity to support affected pupils and motivation to help children with complex problems; solidarity and common purpose amongst teachers, and between teachers and affected children; and effective bridging alliances between schools and their surrounding communities–all hallmarks of HIV-competent communities. We caution against ambitious policy expansions of teachers'' roles without recognition of the personal and social costs of emotional labour, and the need for significant increases in resources and institutional recognition to enable teachers to adopt support roles. We highlight the need for research into how best to create opportunities for teacher recognition in deprived and disorganised institutional settings, and the development of more culturally appropriate notions of caring.     

‘Saviour Siblings’? The Distinction between PGD with HLA Tissue Typing and Preimplantation HLA Tissue Typing

One of the more controversial uses of preimplantation genetic diagnosis (PGD) involves selecting embryos with a specific tissue type so that the child to be born can act as a donor to an existing sibling who requires a haematopoietic stem cell transplant. PGD with HLA tissue typing is used to select embryos that are free of a familial genetic disease and that are also a tissue match for an existing sibling who requires a transplant. Preimplantation HLA tissue typing occurs when parents select embryos that are not at risk of a familial genetic disease to be a match for an existing sibling who requires a transplant. In Victoria, Australia, applications to use PGD with HLA tissue typing are reviewed by the Infertility Treatment Authority on a case by case basis. Preimplantation HLA tissue typing is prohibited prima facie because the embryo to be tested would not be at risk for a genetic abnormality or disease. Arguments for or against the use of PGD/HLA tissue typing are based on several key issues including the commodification and welfare of the donor child. This essay aims to show that that the same arguments apply to both PGD with HLA tissue typing and Preimplantation HLA tissue typing, and that the policy distinction between the two procedures is therefore ethically inconsistent.     

What exactly is ‘local song’ in a population of ortolan buntings with a common dialect?

Previous studies have shown that ortolan buntings (Emberiza hortulana) exhibit apparent dialect variation. Neighbouring males typically share the same final phrase of a simple two-part song. Consequently, the final phrase was considered to be the dialect cue important for discriminating between males from a local population and strangers. Recently, it was shown that in an isolated and fragmented population of the ortolan buntings in Norway there was no local dialect in the above-mentioned sense. Norwegian males often had song types with different final phrases in their repertoire, and had larger repertoires and a lower level of song type sharing than in other populations. It was experimentally revealed that only local songs (L) evoked a strong response in Norwegian males, while these birds did not respond strongly to foreign (F) or hybrid songs composed of local and foreign initial and final phrases in any composition (i.e. both FL and LF songs). These results suggest that, in the Norwegian population, the final phrase of the song is not a sufficient cue for local song dialect recognition. This paper is a further study in which we tested the response of the ortolan bunting males to L, F, FL and LF songs in a typical continuous population (in Poland) in which males share the same single final phrase, i.e. have a common dialect. We found that ortolan bunting males in Poland responded with similar strength to L, FL and LF songs. The majority of males did not respond as strongly to playback of only F songs. Our results suggest that a common final phrase for a population should not be treated as the only signal of ‘locality’. Our results show clear asymmetry in response to hybrid songs with non-local phrases in different populations.     

Are biodiversity ‘hotspots’ correlated with current ecoclimatic stability? A pilot study using the NOAA-AVHRR remote sensing data

The GAC (Global Area Coverage) by the NOAA-AVHRR satellites represents an excellent data set for studying global and regional patterns of variations in surface conditions driven in part by climatic variation. In this pilot study we examined whether biodiversity hotspots, defined from peak concentrations of neoendemics as well as geographically relict forms, differ in ecoclimatic stability from surrounding areas under present-day climatic conditions. Coefficients of variation of the ratio between brightness surface temperature (Ts) and the Normalized Difference Vegetation Index (NDVI) based upon 10 years' monthly composited scenes of tropical Africa revealed distinctive geographical patterns of interannual variability in surface conditions. Regions with a predominance of old species are characterized by spatial uniformity in the ecoclimatic variability, while regions where rapidly radiating groups dominate are spatially complex in this respect. However, the exact hotspots, with peak concentrations of endemic species, are characterized by a local reduction in ecoclimatic variability, or placement on the boundary to a stable region. This relationship was supported statistically by comparing ecoclimatic profiles across montane forests representing hotspots, and those of other montane forests. It is suggested that, because of interactions between prevailing atmospheric flows, topography and vegetation, the impact of extreme weather is moderated locally. The correlation between current stability and aggregates of neoendemics as well as old relics indicate that local moderation of climatic extremes persist through shifting climatic periods, permitting populations of unique species to survive in these places. The results are used to identify study sites for better ground truthing and for paleoclimatological studies which may be useful for more thorough studies of these relationships.     

‘Can he have the test for bipolar,doctor? His dad's got it’: exploring the potential of general practitioners to work with children and young people presenting in primary care with common mental health problems – a clinical initiative

Background General practitioners (GPs) play a key role in assessing and managing adult mental health problems, but this input is not seen in their management of child and adolescent mental health. Mental health problems in 5–19-year-olds are common, yet detection rates in primary care are low. The symptoms of most adult diagnoses of mental health problems are present by mid-adolescence, yet the typical time from onset to diagnosis is 5–15 years. The role of general practice in this area has been underexplored.Aim This pilot study explores the potential of GPs to respond to common mental health problems in children and adolescents.Design Children and young people who would have ordinarily been referred to Child and Adolescent Mental Health Services (CAMHS) were seen in a GP setting. In a UK general practice surgery serving a disadvantaged population.Method Children and young people were seen for an initial biopsychosocial assessment and formulation of the presenting concerns. GP-based interventions were offered as appropriate or referred to CAMHS.Results Data from the first 50 children (2–19 years) are presented. Twenty younger children (10 years and under) and 30 older children (11 years and above) were seen. Eighteen referrals were made to CAMHS. GP interventions included watchful waiting, brief behavioural interventions, non-directive counselling, brief cognitive– behavioural therapy (CBT) and liaison with colleagues in education, CAMHS and the voluntary sector.Conclusion This clinical pilot demonstrates that with adequate time, access to supervision and practice support, children and young people experiencing emotional and behavioural problems associated with common mental health issues can be helped in primary care.