Comparison of bacterioneuston and bacterioplankton dynamics during a phytoplankton bloom in a fjord mesocosm

The bacterioneuston is the community of Bacteria present in surface microlayers, the thin surface film that forms the interface between aquatic environments and the atmosphere. In this study we compared bacterial cell abundance and bacterial community structure of the bacterioneuston and the bacterioplankton (from the subsurface water column) during a phytoplankton bloom mesocosm experiment. Bacterial cell abundance, determined by flow cytometry, followed a typical bacterioplankton response to a phytoplankton bloom, with Synechococcus and high nucleic acid (HNA) bacterial cell numbers initially falling, probably due to selective protist grazing. Subsequently HNA and low nucleic acid (LNA) bacterial cells increased in abundance but Synechococcus did not. There was no significant difference between bacterioneuston and bacterioplankton cell abundances during the experiment. Conversely, distinct and consistent differences between the bacterioneuston and the bacterioplankton community structure were observed. This was monitored simultaneously by Bacteria 16S rRNA gene terminal restriction fragment length polymorphism (T-RFLP) and denaturing gradient gel electrophoresis (DGGE). The conserved patterns of community structure observed in all of the mesocosms indicate that the bacterioneuston is distinctive and non-random

Foetal developmental origins of adult onset non-insulin dependent diabetes mellitus

Abstract There is a global non-insulin dependent diabetes mellitus epidemic, and through understanding the foetal origins of the disease it may become possible to impact the development of the disease. During pregnancy a foetus is entirely dependent on nutrients supplied by the mother via the placenta, meaning alterations to the composition or quantity of maternal nutrition can lead to infants being born with low birth weights. Low birth weight is classified as a weight at birth of ≤ 2.5 kg by the World Health Organisation. In 1990 Dr. David Barker published the “foetal origins of adult disease” hypothesis in order to explain the observed epidemiological relationship between birth-weight and future disease development. It is now understood that alterations to gene expression occurring during foetal development, can then go on to increase the risk developing chronic non-communicable diseases, such as noninsulin dependent diabetes mellitus (NIDDM) in adulthood. However, the exact mechanisms through which this takes place remains unclear. The events during development which result in diminished foetal growth are multifactorial. A foetus’s maximal growth potential is determined genetically, however maternal nutrition both pre and post conception is capable of influencing growth trajectory. This review will examine the existing body of evidence regarding the role of adaptive changes occurring during foetal development in relation to the subsequent development of NIDDM in adulthood. As well as considering the potential mechanisms through which these events could be mediated

Sonic hedgehog functions upstream of disrupted-in-schizophrenia 1 (disc1): implications for mental illness

DISRUPTED-IN-SCHIZOPHRENIA (DISC1) has been one of the most intensively studied genetic risk factors for mental illness since it was discovered through positional mapping of a translocation breakpoint in a large Scottish family where a balanced chromosomal translocation was found to segregate with schizophrenia and affective disorders. While the evidence for it being central to disease pathogenesis in the original Scottish family is compelling, recent genome-wide association studies have not found evidence for common variants at the DISC1 locus being associated with schizophrenia in the wider population. It may therefore be the case that DISC1 provides an indication of biological pathways that are central to mental health issues and functional studies have shown that it functions in multiple signalling pathways. However, there is little information regarding factors that function upstream of DISC1 to regulate its expression and function. We herein demonstrate that Sonic hedgehog (Shh) signalling promotes expression of disc1 in the zebrafish brain. Expression of disc1 is lost in smoothened mutants that have a complete loss of Shh signal transduction, and elevated in patched mutants which have constitutive activation of Shh signalling. We previously demonstrated that disc1 knockdown has a dramatic effect on the specification of oligodendrocyte precursor cells (OPC) in the hindbrain and Shh signalling is known to be essential for the specification of these cells. We show that disc1 is prominently expressed in olig2-positive midline progenitor cells that are absent in smo mutants, while cyclopamine treatment blocks disc1 expression in these cells and mimics the effect of disc1 knock down on OPC specification. Various features of a number of psychiatric conditions could potentially arise through aberrant Hedgehog signalling. We therefore suggest that altered Shh signalling may be an important neurodevelopmental factor in the pathobiology of mental illness

A second independent audit of electroconvulsive therapy in England, 2019: Usage, demographics, consent, and adherence to guidelines and legislation

Objectives. To assess progress towards improving the administering of Electroconvulsive therapy (ECT) in England since an audit covering 2011, 2013 and 2015. The same information was gathered, for 2019, on usage, demographics, consent, and adherence to national guidelines and the Mental Health Act. Design and Methods. Freedom of Information Act requests were sent to 56 National Health Service Trusts. Results. Thirty-seven trusts (66%) provided data. The gradual decline in the use of ECT in England has levelled off at about 2,500 people per year. There was a 47-fold difference between the Trusts with the highest and lowest rates per capita. Most recipients are still women (67%), and over 60 (58%). Only one Trust could report how many people received psychological therapy prior to ECT, as required by government (N.I.C.E.) guidelines. More than a third of ECT (37%) is still given without consent, with 18% of Trusts non-compliant with legislation concerning second opinions. There were slight declines, compared to a previous audit, in the use of standardised depression scales, down to 30%, and standardised measures of cognitive dysfunction, down to 24%. Only six Trusts provided any data for positive outcomes; seven for adverse effects. None provided data on efficacy or adverse effects beyond end of treatment. Twelve used identical sentences to each other, verbatim, in response to one or more questions. Conclusions. Given the apparent failure of current monitoring and accrediting ECT clinics in England, by the Royal College of Psychiatrists’ ECT Accreditation Service (ECTAS), an independent government sponsored review is urgently needed

The role of Sox6 in zebrafish muscle fiber type specification

Background The transcription factor Sox6 has been implicated in regulating muscle fiber type-specific gene expression in mammals. In zebrafish, loss of function of the transcription factor Prdm1a results in a slow to fast-twitch fiber type transformation presaged by ectopic expression of sox6 in slow-twitch progenitors. Morpholino-mediated Sox6 knockdown can suppress this transformation but causes ectopic expression of only one of three slow-twitch specific genes assayed. Here, we use gain and loss of function analysis to analyse further the role of Sox6 in zebrafish muscle fiber type specification. Methods The GAL4 binary misexpression system was used to express Sox6 ectopically in zebrafish embryos. Cis-regulatory elements were characterized using transgenic fish. Zinc finger nuclease mediated targeted mutagenesis was used to analyse the effects of loss of Sox6 function in embryonic, larval and adult zebrafish. Zebrafish transgenic for the GCaMP3 Calcium reporter were used to assay Ca2+ transients in wild-type and mutant muscle fibres. Results Ectopic Sox6 expression is sufficient to downregulate slow-twitch specific gene expression in zebrafish embryos. Cis-regulatory elements upstream of the slow myosin heavy chain 1 (smyhc1) and slow troponin c (tnnc1b) genes contain putative Sox6 binding sites required for repression of the former but not the latter. Embryos homozygous for sox6 null alleles expressed tnnc1b throughout the fast-twitch muscle whereas other slow-specific muscle genes, including smyhc1, were expressed ectopically in only a subset of fast-twitch fibers. Ca2+ transients in sox6 mutant fast-twitch fibers were intermediate in their speed and amplitude between those of wild-type slow- and fast-twitch fibers. sox6 homozygotes survived to adulthood and exhibited continued misexpression of tnnc1b as well as smaller slow-twitch fibers. They also exhibited a striking curvature of the spine. Conclusions The Sox6 transcription factor is a key regulator of fast-twitch muscle fiber differentiation in the zebrafish, a role similar to that ascribed to its murine ortholog

Comparison of methods for evaluating the suitability of Vertisols for Gossypium hirsutum (Bt cotton) in two contrasting agro-ecological regions

This is the author accepted manuscript. The final version is available from Taylor and Francis (Routledge) via the DOI in this record.Cotton (Gossypium sp.) is a major crop grown under rainfed conditions in Vertisols and associated soils in semi-arid tropical (SAT) regions of Peninsular India. In recent years, cotton productivity has declined due to various biophysical factors including pest and diseases, seasonal water stress soil degradation and poor crop management practices. In this study, we compare two methods for evaluating the suitability of Vertisols for cotton in contrasting two agro-ecological regions viz., sub-humid moist (SHM) region and semi-arid dry(SAD) were characterized. Twelve cotton growing Vertisols (seven from SHM and five from SAD) were evaluated for their suitability for cotton cultivation using soil quality index (SQI) and modified Sys-FAO method. SQIs were calculated using the weighted additive index from transformed scores of selected indicators by principal component analysis. For Sys-FAO method both biophysical and soil characteristics were considered for suitability evaluation. We found that the soils of SHM region were moderately suitable for cotton cultivation with soil moisture as the major limiting factor, whereas the soils of SAD region are marginally suitable due to high exchangeable sodium percentage and poor hydraulic conductivity. From this, it may be concluded that the weighted SQI has better agreement with the cotton yield

Plasma-generated poly(allyl alcohol) antifouling coatings for cellular attachment

Conformal poly(allyl alcohol) (PAA) coatings were grown on a biomedical grade polyurethane scaffold using pulsed plasma polymerization of the allyl alcohol monomer. The creation of a continuous wave polymer primer layer increases the interfacial adhesion and stability of a subsequent pulsed plasma deposited PAA film. The resulting PAA coatings are strongly hydrophilic and stable following 7 days incubation in biological media. Films prepared through this energyefficient, two-step process promote human dermal fibroblast cell culture, while resisting E. coli biofilm formation

Cyber-enabled tradecraft and contemporary espionage: assessing the implications of the tradecraft paradox on agent recruitment in Russia and China

The acquisition of clandestine human sources – or agents – inside Russia and China likely remains the key priority for Western HUMINT agencies, and yet their ability to do this safely is quickly waning. This paper considers the utility of cyberspace for espionage recruitment in these two hard target states, and assesses its value as a potential solution to emerging surveillance threats. With the aid of history, this paper proposes that hard target espionage is fundamentally afflicted by a tradecraft paradox, one that will severely curtail the utility of cyberspace to agent recruitment