Monitoring to detect changes in water quality to meet policy objectives

Detecting change in water quality is key to providing evidence of progress towards meeting water quality objectives. A key measure for detecting change is statistical power. Here we calculate statistical power for all regularly (monthly) monitored streams in New Zealand to test the effectiveness of monitoring for policy that aims to decrease contaminant (phosphorus and nitrogen species, E. coli and visual clarity) concentrations to threshold levels in 5 or 20 years. While > 95% of all monitored sites had sufficient power and samples to detect change in nutrients and clarity over 20 years, on average, sampling frequency would have to double to detect changes in E. coli. Furthermore, to detect changes in 5 years, sampling for clarity, dissolved reactive phosphorus and E. coli would have to increase up to fivefold. The cost of sampling was predicted to increase 5.3 and 4.1 times for 5 and 20 years, respectively. A national model of statistical power was used to demonstrate that a similar number of samples (and cost) would be required for any new monitoring sites. Our work suggests that demonstrating the outcomes of implementing policy for water quality improvement may not occur without a step change in investment into monitoring systems. Emerging sampling technologies have potential to reduce the cost, but existing monitoring networks may also have to be rationalised to provide evidence that water quality is meeting objectives. Our study has important implications for investment decisions involving balancing the need for intensively sampled sites where changes in water quality occur rapidly versus other sites which provide long-term time series.

A Global Database of Soil Plant Available Phosphorus

Soil phosphorus drives food production that is needed to feed a growing global population. However, knowledge of plant available phosphorus stocks at a global scale is poor but needed to better match phosphorus fertiliser supply to crop demand. We collated, checked, converted, and filtered a database of c. 575,000 soil samples to c. 33,000 soil samples of soil Olsen phosphorus concentrations. These data represent the most up-to-date repository of freely available data for plant available phosphorus at a global scale. We used these data to derive a model (R² = 0.54) of topsoil Olsen phosphorus concentrations that when combined with data on bulk density predicted the distribution and global stock of soil Olsen phosphorus. We expect that these data can be used to not only show where plant available P should be boosted, but also where it can be drawn down to make more efficient use of fertiliser phosphorus and to minimise likely phosphorus loss and degradation of water quality.

1294 ASSESSMENT AND MANAGEMENT OF FRAILTY: A SURVEY OF HEALTHCARE PROFESSIONALS

Introduction

By 2030, it is estimated that 25% of Europeans will be aged over 65. [Dugarova; UN Development Programme; 2017] Frailty in this group is a key contributor to poorer outcomes. [Eamer; BMC Anesthesiology; 2017; 17:99] The term is common in healthcare but research into the issues faced by staff around assessment and management of frailty has been limited. We undertook a survey to identify challenges faced in providing care to those living with frailty and considered potential interventions.

Method

The survey was across three hospitals in our health board (which serves a population of around 390,000 with a range of services). [SBUHB;2022] It was developed iteratively through consultation in a multidisciplinary group and adapted questions from other similar validated surveys. [Eamer; BMC Anesthesiology; 2017; 17:99][Taylor; Future Healthcare Journal; 2017; 4(3):207-212].

Results

218 responses were received covering a variety of medical and surgical specialties. Participants showed a strong (80%) self-reported understanding of frailty as a clinical concept, but only 46% felt confident in their ability to assess patients for frailty. 74% stated they would benefit from more education on frailty. Other barriers included systemic challenges such as staffing and social care, but also a lack of understanding of frailty by patients and relatives which impacted shared decision-making.

Conclusions

The survey showed a significant demand for more education, especially awareness of pathways and assessment methods. It also highlighted the issue of patients’ (and relatives’) lack of understanding of frailty. In response, we are planning a targeted multi-disciplinary educational programme on frailty across the health board, as well as introducing patient information leaflets.

RedoxiFluor: A microplate technique to quantify target-specific protein thiol redox state in relative percentage and molar terms

Unravelling how reactive oxygen species regulate fundamental biological processes is hampered by the lack of an accessible microplate technique to quantify target-specific protein thiol redox state in percentages and moles. To meet this unmet need, we present RedoxiFluor. RedoxiFluor uses two spectrally distinct thiol-reactive fluorescent conjugated reporters, a capture antibody, detector antibody and a standard curve to quantify target-specific protein thiol redox state in relative percentage and molar terms. RedoxiFluor can operate in global mode to assess the redox state of the bulk thiol proteome and can simultaneously assess the redox state of multiple targets in array mode. Extensive proof-of-principle experiments robustly validate the assay principle and the value of each RedoxiFluor mode in diverse biological contexts. In particular, array mode RedoxiFluor shows that the response of redox-regulated phosphatases to lipopolysaccharide (LPS) differs in human monocytes. Specifically, LPS increased PP2A-, SHP1-, PTP1B-, and CD45-specific reversible thiol oxidation without changing the redox state of calcineurin, PTEN, and SHP2. The relative percentage and molar terms are interpretationally useful and define the most complete and extensive microplate redox analysis achieved to date. RedoxiFluor is a new antibody technology with the power to quantify relative target-specific protein thiol redox state in percentages and moles relative to the bulk thiol proteome and selected other targets in a widely accessible, simple and easily implementable microplate format.

Cryopreservation of Xenopus Sperm and In Vitro Fertilization Using Frozen Sperm Samples

The cryopreservation of Xenopus sperm allows for a significant reduction of the number of animals that must be kept, more efficient archiving of genetically altered (GA) lines, and easy exchange of lines with other laboratories, leading to improvements in animal welfare and cost efficiency. In this protocol, sperm from Xenopus laevis or Xenopus tropicalis are frozen using straightforward techniques and standard laboratory equipment. Testes are macerated in Leibovitz's L-15 medium, mixed with a simple cryoprotectant made from egg yolk and sucrose, and frozen slowly overnight in a polystyrene box at -80°C. Unlike mouse sperm, Xenopus sperm can be stored at -80°C rather than in liquid nitrogen, further reducing costs. The frozen sperm are then used for in vitro fertilization.

ALISA: A microplate assay to measure protein thiol redox state

Measuring protein thiol redox state is central to understanding redox signalling in health and disease. The lack of a microplate assay to measure target specific protein thiol redox state rate-limits progress on accessibility grounds: redox proteomics is inaccessible to most. Developing a microplate assay is important for accelerating discovery by widening access to protein thiol redox biology. Beyond accessibility, enabling high throughput time- and cost-efficient microplate analysis is important. To meet the pressing need for a microplate assay to measure protein thiol redox state, we present the Antibody-Linked Oxi-State Assay (ALISA). ALISA uses a covalently bound capture antibody to bind a thiol-reactive fluorescent conjugated maleimide (F-MAL) decorated target. The capture antibody-target complex is labelled with an amine-reactive fluorescent N-hydroxysuccinimide ester (F-NHS) to report total protein. The covalent bonds that immobilise the capture antibody to the epoxy group functionalised microplate enable one to selectively elute the target. Target specific redox state is ratiometrically calculated as: F-MAL (i.e., reversible thiol oxidation)/F-NHS (i.e., total protein). After validating the assay principle (i.e., increased target specific reversible thiol oxidation increases the ratio), we used ALISA to determine whether fertilisation-a fundamental biological process-changes Akt, a serine/threonine protein kinase, specific reversible thiol oxidation. Fertilisation significantly decreases Akt specific reversible thiol oxidation in Xenopus laevis 2-cell zygotes compared to unfertilised eggs. ALISA is an accessible microplate assay to advance knowledge of protein thiol redox biology in health and disease.

O8: DIRECT MANIPULATION OF THE INTESTINAL MICROBIOME TO INFLUENCE POST-OPERATIVE OUTCOMES

Introduction

Distal feeding (DF) involves intubation of the distal limb of a loop ileostomy to feed with a prebiotic mix. Studies suggest that distally feeding patients following anterior resection prior to ileostomy closure may be beneficial as a form of bowel pre-habilitation. These pilot data examine the adaptive immune response to DF.

Method

Ten healthy controls with an intact GI tract were compared with 10 patients following rectal cancer resection and chemo/radiotherapy, prior to closure of ileostomy over 8 weeks of DF. We examined B and T cell memory responses from peripheral blood using cell proliferation assays. Cells were cultured with dead antigen to reflect the microbiota in the small and large bowel. Two negative and two positive controls were used to assess minimal and maximum cell proliferation.

Result

B cell responses prior to DF were increased in the defunctioned group compared to the normal controls to significance (p=0.0014). After 8 weeks of DF the groups were comparable. T cell responses to bacteria had significant differences in proliferation rate following DF commencement, CD4 week 0 vs 3 p=0.0001, week 3 vs 8 p=0.000034, CD8 week 0 vs 3 p=0.0001, week 3-8 p=0.00024). In individual patients, CD4 responses were shown to shift from responses to facultative aerobic species, to strict anaerobes.

Conclusion

These data suggest that distal feeding fundamentally resets peripheral circulating memory and it may be of use in pre-habilitating the bowel prior to restoration of continuity. Early clinical data suggests that distal feeding improves post-operative outcomes.

Take-home message

distal feeding is an easy pre-operative intervention that has a significant effect on cell proliferation and antigen response, which may contribute to improved post operative outcomes.

Reversible Thiol Oxidation Inhibits the Mitochondrial ATP Synthase in Xenopus Laevis Oocytes

Oocytes are postulated to repress the proton pumps (e.g., complex IV) and ATP synthase to safeguard mitochondrial DNA homoplasmy by curtailing superoxide production. Whether the ATP synthase is inhibited is, however, unknown. Here we show that: oligomycin sensitive ATP synthase activity is significantly greater (~170 vs. 20 nmol/min^-1/mg^-1) in testes compared to oocytes in Xenopus laevis (X. laevis). Since ATP synthase activity is redox regulated, we explored a regulatory role for reversible thiol oxidation. If a protein thiol inhibits the ATP synthase, then constituent subunits must be reversibly oxidised. Catalyst-free trans-cyclooctene 6-methyltetrazine (TCO-Tz) immunocapture coupled to redox affinity blotting reveals several subunits in F₁ (e.g., ATP-α-F₁) and F_o (e.g., subunit c) are reversibly oxidised. Catalyst-free TCO-Tz Click PEGylation reveals significant (~60%) reversible ATP-α-F₁ oxidation at two evolutionary conserved cysteine residues (C²⁴⁴ and C²⁹⁴) in oocytes. TCO-Tz Click PEGylation reveals ~20% of the total thiols in the ATP synthase are substantially oxidised. Chemically reversing thiol oxidation significantly increased oligomycin sensitive ATP synthase activity from ~12 to 100 nmol/min^-1/mg^-1 in oocytes. We conclude that reversible thiol oxidation inhibits the mitochondrial ATP synthase in X. laevis oocytes.

Global mapping of freshwater nutrient enrichment and periphyton growth potential

Periphyton (viz. algal) growth in many freshwater systems is associated with severe eutrophication that can impair productive and recreational use of water by billions of people. However, there has been limited analysis of periphyton growth at a global level. To predict where nutrient over-enrichment and undesirable periphyton growth occurs, we combined several databases to model and map global dissolved and total nitrogen (N) and phosphorus (P) concentrations, climatic and catchment characteristics for up to 1406 larger rivers that were analysed between 1990 and 2016. We predict that 31% of the global landmass contained catchments may exhibit undesirable levels of periphyton growth. Almost three-quarters (76%) of undesirable periphyton growth was caused by P-enrichment and mapped to catchments dominated by agricultural land in North and South America and Europe containing 1.7B people. In contrast, undesirable periphyton growth due to N-enrichment was mapped to parts of North Africa and parts of the Middle East and India affecting 280 M people. The findings of this global modelling approach can be used by landowners and policy makers to better target investment and actions at finer spatial scales to remediate poor water quality owing to periphyton growth.

Liquid Chromatographic Determination of Glyphosate in Water-Soluble Granular Formulations: Collaborative Study

A liquid chromatographic (LC) method for the determination of glyphosate in various water-soluble granular formulations was tested by 28 laboratories. Samples were dissolved in mobile phase and injected directly into an LC system with a 25 cm SAX column and a mobile phase of 96% aqueous buffer solution, 0.0062M KH2PO4, and 4% methanol. Detection was by UV absorption at 195 nm. Manual or automated injections were made via fixed-volume loops. Calculations were based on peak area comparisons with external standards. The collaborative study analyzed 5 matched pairs of 4 water-soluble granular formulations, with one determination per sample. The study generated 138 matched pairs, which were analyzed by using the AOAC spreadsheet and Youden’s matched-pair calculations. Coefficients of variation for the 4 formulations ranged from 0.65 to 1.37%. The LC method for the determination of glyphosate in water-soluble granular formulations has been adopted first action by AOAC INTERNATIONAL.

Catalyst-free Click PEGylation reveals substantial mitochondrial ATP synthase sub-unit alpha oxidation before and after fertilisation

Using non-reducing Western blotting to assess protein thiol redox state is challenging because most reduced and oxidised forms migrate at the same molecular weight and are, therefore, indistinguishable. While copper catalysed Click chemistry can be used to ligate a polyethylene glycol (PEG) moiety termed Click PEGylation to mass shift the reduced or oxidised form as desired, the potential for copper catalysed auto-oxidation is problematic. Here we define a catalyst-free trans-cyclooctene-methyltetrazine (TCO-Tz) inverse electron demand Diels Alder chemistry approach that affords rapid (k ~2000 M⁻¹ s⁻¹), selective and bio-orthogonal Click PEGylation. We used TCO-Tz Click PEGylation to investigate how fertilisation impacts reversible mitochondrial ATP synthase F₁-F_o sub-unit alpha (ATP-α-F₁) oxidation—an established molecular correlate of impaired enzyme activity—in Xenopus laevis. TCO-Tz Click PEGylation studies reveal substantial (~65%) reversible ATP-α-F₁ oxidation at evolutionary conserved cysteine residues (i.e., C²⁴⁴ and C²⁹⁴) before and after fertilisation. A single thiol is, however, preferentially oxidised likely due to greater solvent exposure during the catalytic cycle. Selective reduction experiments show that: S-glutathionylation accounts for ~50–60% of the reversible oxidation observed, making it the dominant oxidative modification type. Intermolecular disulphide bonds may also contribute due to their relative stability. Substantial reversible ATP-α-F₁ oxidation before and after fertilisation is biologically meaningful because it implies low mitochondrial F₁-F_o ATP synthase activity. Catalyst-free TCO-Tz Click PEGylation is a valuable new tool to interrogate protein thiol redox state in health and disease.

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Catalyst-free TCO-Tz Click PEGylation can assess protein thiol redox state.

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ATP-α-F₁ is substantially oxidised before and after fertilisation.

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S-glutathionylation is the dominant oxidative modification type.

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A single thiol is preferentially oxidised due to greater solvent exposure.

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Catalyst-free TCO-Tz Click PEGylation is a valuable new tool.

Xenopus Resources: Transgenic, Inbred and Mutant Animals, Training Opportunities, and Web-Based Support

Two species of the clawed frog family, Xenopus laevis and X. tropicalis, are widely used as tools to investigate both normal and disease-state biochemistry, genetics, cell biology, and developmental biology. To support both frog specialist and non-specialist scientists needing access to these models for their research, a number of centralized resources exist around the world. These include centers that hold live and frozen stocks of transgenic, inbred and mutant animals and centers that hold molecular resources. This infrastructure is supported by a model organism database. Here, we describe much of this infrastructure and encourage the community to make the best use of it and to guide the resource centers in developing new lines and libraries.

Adipose tissue macrophages develop from bone marrow-independent progenitors in Xenopus laevis and mouse

ATMs have a metabolic impact in mammals as they contribute to metabolically harmful AT inflammation. The control of the ATM number may have therapeutic potential; however, information on ATM ontogeny is scarce. Whereas it is thought that ATMs develop from circulating monocytes, various tissue-resident Mϕs are capable of self-renewal and develop from BM-independent progenitors without a monocyte intermediate. Here, we show that amphibian AT contains self-renewing ATMs that populate the AT before the establishment of BM hematopoiesis. Xenopus ATMs develop from progenitors of aVBI. In the mouse, a significant amount of ATM develops from the yolk sac, the mammalian equivalent of aVBI. In summary, this study provides evidence for a prenatal origin of ATMs and shows that the study of amphibian ATMs can enhance the understanding of the role of the prenatal environment in ATM development.

Towards Attosecond High-Energy Electron Bunches: Controlling Self-Injection in Laser-Wakefield Accelerators Through Plasma-Density Modulation

Self-injection in a laser-plasma wakefield accelerator is usually achieved by increasing the laser intensity until the threshold for injection is exceeded. Alternatively, the velocity of the bubble accelerating structure can be controlled using plasma density ramps, reducing the electron velocity required for injection. We present a model describing self-injection in the short-bunch regime for arbitrary changes in the plasma density. We derive the threshold condition for injection due to a plasma density gradient, which is confirmed using particle-in-cell simulations that demonstrate injection of subfemtosecond bunches. It is shown that the bunch charge, bunch length, and separation of bunches in a bunch train can be controlled by tailoring the plasma density profile.

An optimized method for cryogenic storage of Xenopus sperm to maximise the effectiveness of research using genetically altered frogs

Cryogenic storage of sperm from genetically altered Xenopus improves cost effectiveness and animal welfare associated with their use in research; currently it is routine for X. tropicalis but not reliable for X. laevis. Here we compare directly the three published protocols for Xenopus sperm freeze-thaw and determine whether sperm storage temperature, method of testes maceration and delays in the freezing protocols affect successful fertilisation and embryo development in X. laevis. We conclude that the protocol is robust and that the variability observed in fertilisation rates is due to differences between individuals. We show that the embryos made from the frozen-thawed sperm are normal and that the adults they develop into are reproductively indistinguishable from others in the colony. This opens the way for using cryopreserved sperm to distribute dominant genetically altered (GA) lines, potentially saving travel-induced stress to the male frogs, reducing their numbers used and making Xenopus experiments more cost effective.

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Xenopus cryopreservation is robust using an optimized method.

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Success is dependent on the quality of animals from which the sperm are taken.

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Frozen sperm may now be used to distribute lines and wild-type male gametes around the world.

Follicular helper T cells are responsible for IgE responses to Der p 1 following house dust mite sensitization in mice

BACKGROUND

Th2 cells have long been considered responsible for the switching of B cells to production of IgE during cognate interaction, primarily due to their expression of CD40L and secretion of IL-4. This concept has been challenged by the more recent definition of follicular helper T cells (Tfh) as the key T cell subset in B cell isotype switching, due to their physical location at the boundary of T cell:B cell areas in lymphoid follicles and ability to express IL-4 and CD40L.

OBJECTIVE

To determine whether Tfh cells are responsible for IgE responses to Der p 1 allergen after house dust mite (HDM)-induced allergic sensitization.

METHODS

Mice deficient in Tfh cells were sensitized to HDM and Der p 1-specific IgE measured by ELISA.

RESULTS

Mice with a mutation in T cell-expressed IL-6R were unable to expand Tfh populations after HDM sensitization, and their anti-Der p 1 IgE, IgG1 and total IgE responses were reduced by 80-90% compared with wild-type mice. These animals displayed unaltered lung Th2 and eosinophilic responses after intranasal HDM challenge and normal IL-4 production, but B cell infiltration of the airways was abrogated.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data indicate that Tfh cells are largely responsible for switching B cells to IgE synthesis, most likely via an IgG1(+) intermediate. However, Th2 cells are the major source of IL-4 during HDM sensitization and this might contribute to IgE synthesis at a stage distal to Tfh-mediated isotype switching. The IL-6/follicular helper T cell pathway is a potential therapeutic target in allergic disease.

Inbreeding Ratio and Genetic Relationships among Strains of the Western Clawed Frog, Xenopus tropicalis

The Western clawed frog, Xenopus tropicalis, is a highly promising model amphibian, especially in developmental and physiological research, and as a tool for understanding disease. It was originally found in the West African rainforest belt, and was introduced to the research community in the 1990s. The major strains thus far known include the Nigerian and Ivory Coast strains. However, due to its short history as an experimental animal, the genetic relationship among the various strains has not yet been clarified, and establishment of inbred strains has not yet been achieved. Since 2003 the Institute for Amphibian Biology (IAB), Hiroshima University has maintained stocks of multiple X. tropicalis strains and conducted consecutive breeding as part of the National BioResource Project. In the present study we investigated the inbreeding ratio and genetic relationship of four inbred strains at IAB, as well as stocks from other institutions, using highly polymorphic microsatellite markers and mitochondrial haplotypes. Our results show successive reduction of heterozygosity in the genome of the IAB inbred strains. The Ivory Coast strains clearly differed from the Nigerian strains genetically, and three subgroups were identified within both the Nigerian and Ivory Coast strains. It is noteworthy that the Ivory Coast strains have an evolutionary divergent genetic background. Our results serve as a guide for the most effective use of X. tropicalis strains, and the long-term maintenance of multiple strains will contribute to further research efforts.

The emergence of Pax7-expressing muscle stem cells during vertebrate head muscle development

Pax7 expressing muscle stem cells accompany all skeletal muscles in the body and in healthy individuals, efficiently repair muscle after injury. Currently, the in vitro manipulation and culture of these cells is still in its infancy, yet muscle stem cells may be the most promising route toward the therapy of muscle diseases such as muscular dystrophies. It is often overlooked that muscular dystrophies affect head and body skeletal muscle differently. Moreover, these muscles develop differently. Specifically, head muscle and its stem cells develop from the non-somitic head mesoderm which also has cardiac competence. To which extent head muscle stem cells retain properties of the early head mesoderm and might even be able to switch between a skeletal muscle and cardiac fate is not known. This is due to the fact that the timing and mechanisms underlying head muscle stem cell development are still obscure. Consequently, it is not clear at which time point one should compare the properties of head mesodermal cells and head muscle stem cells. To shed light on this, we traced the emergence of head muscle stem cells in the key vertebrate models for myogenesis, chicken, mouse, frog and zebrafish, using Pax7 as key marker. Our study reveals a common theme of head muscle stem cell development that is quite different from the trunk. Unlike trunk muscle stem cells, head muscle stem cells do not have a previous history of Pax7 expression, instead Pax7 expression emerges de-novo. The cells develop late, and well after the head mesoderm has committed to myogenesis. We propose that this unique mechanism of muscle stem cell development is a legacy of the evolutionary history of the chordate head mesoderm.

Validation of the sperm chromatin dispersion (SCD) test in the amphibian Xenopus laevis using in situ nick translation and comet assay

The integrity of sperm DNA is becoming increasingly recognised as an important parameter of semen quality, but there are no published reports of this procedure for any amphibian. The primary aim of this study was to apply a modified sperm chromatin dispersion (SCD) test (Halomax) to an amphibian sperm model (African clawed frog; Xenopus laevis) and to validate the assay against in situ nick translation (ISNT) and the double-comet assay procedure. Inactivated spermatozoa were collected from fresh testes (n = 3). Sperm DNA fragmentation (SDF) for each sperm sample was conducted immediately following activation (T0) and again after 1 h (T1) and 24 h (T24) of incubation at room temperature in order to produce a range of spermatozoa with differing levels of DNA damage. The SCD procedure resulted in the production of three nuclear morphotypes; amphibian sperm morphotype 1 (ASM-1) and ASM-2 showed no evidence of DNA damage, whereas ASM-3 spermatozoa were highly fragmented with large halos of dispersed DNA fragments and a reduced nuclear core. ISNT confirmed that ASM-3 nuclei contained damaged DNA. There was a significant correlation (r = 0.9613) between the levels of ASM-3 detected by the SCD test and SDF revealed by the double-comet assay.

Patient Reported Experience Measures (PREMs) in chronic heart failure

BACKGROUND

Patient Reported Experience Measures (PREMs) is an essential tool for assessing the quality of chronic disease management. The optimal method for delivering a PREMs survey however is unknown. This study reports two methods for assessing PREMs in patients with chronic heart failure (CHF).

METHODS

A bespoke online and postal survey delivered to community-based CHF patients in Scotland.

RESULTS

A total of 121 patients (73 postal and 48 online) completed the survey. The online cohort were younger, had less contact with a CHF nurse, were more likely to see a CHF doctor and seemed less satisfied with the quality of clinical services. The postal cohort returned fewer negative comments (20 [27.4%] vs 28 [58.3%]; p<0.0001). Several recurring themes were identified.

CONCLUSIONS

There are differences in participation rates and responses between postal and online surveys; the accuracy of the feedback gathered using these methods is therefore difficult to determine. Clinicians should consider offering a range of options to enable patients to reflect and 'voice' their opinions regarding clinical services.

Can an epilepsy nurse specialist-led self-management intervention reduce attendance at emergency departments and promote well-being for people with severe epilepsy? A non-randomised trial with a nested qualitative phase

Objectives

To (1) describe the characteristics and service use of people with established epilepsy (PWE) who attend the emergency department (ED); (2) evaluate the economic impact of PWE who attend the ED; (3) determine the effectiveness and cost-effectiveness of an epilepsy nurse specialist (ENS)-led self-management intervention plus treatment as usual (TAU) compared with TAU alone in reducing ED use and promoting well-being; (4) describe patients' views of the intervention; and (5) explore their reasons for attending the ED.

Design

Non-randomised trial with nested qualitative study.

Setting

The EDs of three inner London hospitals. The EDs each offer similar services and support a similar local population, which made a comparison of patient outcomes reasonable.

Participants

Adults diagnosed with epilepsy for ≥ 1 year were prospectively identified from the EDs by presenting symptom/discharge diagnosis. We recruited 85 of 315 patients with 44 forming the intervention group and 41 the comparison group.

Intervention

Intervention participants were offered two one-to-one outpatient sessions delivered by an ENS who aimed to optimise self-management skills and knowledge of appropriate emergency service use. The first session lasted for 45–60 minutes and the second for 30 minutes.

Main outcome measures

The primary outcome was the number of ED visits that participants reported making over the 6 months preceding the 12-month follow-up. Secondary outcomes were visits reported at the 6-month follow-up and scores on psychosocial measures.

Results

In the year preceding recruitment, the 85 participants together made 270 ED visits. The frequency of their visits was positively skewed, with 61% having attended multiple times. The mean number of visits per participant was 3.1 [standard deviation (SD) 3.6] and the median was two (interquartile range 1–4). Mean patient service cost was £2355 (SD £2455). Compared with findings in the general epilepsy population, participants experienced more seizures and had greater anxiety, lower epilepsy knowledge and greater perceived stigma. Their outpatient care was, however, consistent with National Institute for Health and Clinical Excellence recommendations. In total, 81% of participants were retained at the 6- and 12-month follow-ups, and 80% of participants offered the intervention attended. Using intention-to-treat analyses, including those adjusted for baseline differences, we found no significant effect of the intervention on ED use at the 6-month follow-up [adjusted incidence rate ratio (IRR) 1.75, 95% confidence interval (CI) 0.93 to 3.28] or the 12-month follow-up (adjusted IRR 1.92, 95% CI 0.68 to 5.41), nor on any psychosocial outcomes. Because they spent less time as inpatients, however, the average service cost of intervention participants over follow-up was less than that of TAU participants (adjusted difference £558, 95% CI –£2409 to £648). Lower confidence in managing epilepsy and more felt stigma at baseline best predicted more ED visits over follow-up. Interviews revealed that patients generally attended because they had no family, friend or colleague nearby who had the confidence to manage a seizure. Most participants receiving the intervention valued it, including being given information on epilepsy and an opportunity to talk about their feelings. Those reporting most ED use at baseline perceived the most benefit.

Conclusions

At baseline, > 60% of participants who had attended an ED in the previous year had reattended in the same year. In total, 50% of their health service costs were accounted for by ED use and admissions. Low confidence in their ability to manage their epilepsy and a greater sense of stigma predicted frequent attendance. The intervention did not lead to a reduction in ED use but did not cost more, partly because those receiving the intervention had shorter average hospital stays. The most common reason reported by PWE for attending an ED was the lack of someone nearby with sufficient experience of managing a seizure. Those who attended an ED frequently and received the intervention were more likely to report that the intervention helped them. Our findings on predictors of ED use clarify what causes ED use and suggest that future interventions might focus more on patients' perceptions of stigma and on their confidence in managing epilepsy. If addressed, ED visits might be reduced and efficiency savings generated.

Trial registration

Current Controlled Trials ISRCTN06469947.

Funding

This project was funded by the NIHR Health Services and Delivery Research programme and will be published in full inHealth Services and Delivery Research; Vol. 1, No. 9. See the HSDR programme website for further project information.

Husbandry of Xenopus tropicalis

Xenopus tropicalis combine the advantages of X. laevis, for example using explants and targeted gain of function, with the ability to take classical genetics approaches to answering cell and developmental biology questions making it arguably the most versatile of the model organisms. Against this background, husbandry of X. tropicalis is less well developed than for its larger, more robust relative. Here we describe the methods used to keep and breed these frogs successfully.

The biology of platelet-rich plasma and its application in trauma and orthopaedic surgery: a review of the literature

Although mechanical stabilisation has been a hallmark of orthopaedic surgical management, orthobiologics are now playing an increasing role. Platelet-rich plasma (PRP) is a volume of plasma fraction of autologous blood having platelet concentrations above baseline. The platelet alpha granules are rich in growth factors that play an essential role in tissue healing, such as transforming growth factor-beta, vascular endothelial growth factor, and platelet-derived growth factor. PRP is used in various surgical fields to enhance bone and soft-tissue healing by placing supraphysiological concentrations of autologous platelets at the site of tissue damage. The easily obtainable PRP and its possible beneficial outcome hold promise for new regenerative treatment approaches. The aim of this literature review was to describe the bioactivities of PRP, to elucidate the different techniques for PRP preparation, to review animal and human studies, to evaluate the evidence regarding the use of PRP in trauma and orthopaedic surgery, to clarify risks, and to provide guidance for future research.

Association between human cases and poultry outbreaks of highly pathogenic avian influenza in Vietnam from 2003 to 2007: a nationwide study

This study quantifies the spatio-temporal association between outbreaks of highly pathogenic avian influenza H5N1 in domestic poultry (n = 3050) and human cases (n = 99) in Vietnam during 2003-2007, using rare events logistic regression. After adjusting for the effect of known confounders, the odds of a human case being reported to authorities increased by a factor of 6.17 [95% confidence interval (CI) 3.33-11.38] and 2.48 (95% CI 1.20 - 5.13) if poultry outbreaks were reported in the same district 1 week and 4 weeks later respectively. When jointly considering poultry outbreaks in the same and neighbouring districts, occurrence of poultry outbreaks in the same week, 1-week later, and 4 weeks later increased the odds of a human case by a factor of 2.75 (95% CI 1.43-5.30), 2.56 (95% CI 1.31-5.00) and 2.70 (95% CI 1.56-4.66) respectively. Our study found evidence of different levels of association between human cases and poultry outbreaks in the North and the South of the country. When considering the 9-week interval extending from 4 weeks before to 4 weeks after the week of reporting a human case, in the South poultry outbreaks were recorded in 58% of cases in the same district and 83% of cases in either the same or neighbouring districts, whereas in the North the equivalent results were only 23% and 42%. The strength of the association between human and poultry cases declined over the study period. We conclude that owner reporting of clinical disease in poultry needs to be enhanced by targeted agent-specific surveillance integrated with preventive and other measures, if human exposure is to be minimized.

Blockade of chronic graft-versus-host disease by alloantigen-induced CD4+CD25+Foxp3+ regulatory T cells in nonlymphopenic hosts

CD4(+)CD25(+) regulatory T cells (Tregs) are well known to suppress immunopathology induced in lymphopenic animals following T cell reconstitution, including acute graft-versus-host disease (GVHD) post-bone marrow transplantation. The regulatory potential of this subset in nonlymphopenic hosts and in chronic, Th2-mediated GVHD is less clear. We have generated alloantigen-specific cells from CD4(+)CD25(+) populations stimulated with MHC-disparate dendritic cells and found them to express a stable Treg forkhead box p3(+) phenotype with enhanced suppressive activity mediated by cell contact. When transferred into nonlymphopenic F1 hosts, nonspecific Tregs proliferated as rapidly as CD4(+)CD25(-) cells but displayed distinct growth kinetics in vitro. Tregs, expanded in response to alloantigen in vitro, displayed greatly enhanced suppressive activity, which was partially antigen-specific. They were effective inhibitors of chronic GVHD, blocking donor cell engraftment, splenomegaly, autoantibody production, and glomerulonephritis. CD25(+) and CD25(-) cells were equally susceptible to inhibition by immunosuppressive drugs targeting TCR signaling and rapamycin, but Tregs were resistant to inhibition by dexamethasone. The data indicate that alloantigen-driven expansion, rather than homeostatic proliferation, is key to the effectiveness of CD4(+)CD25(+) Tregs in GVHD and suggest that cellular therapy with alloantigen-induced Tregs in combination with glucocorticoid treatment would be effective in prevention of chronic GVHD after immune reconstitution.

Additional nucleoli and NOR activity during meiotic prophase I in larch (Larix decidua Mill.)

Transcriptional activity was investigated in successive stages of prophase I (male meiosis) of larch meiocytes. Br-UTP incorporated into RNA was detected by light and electron microscopy. Two peaks of RNA synthesis were identified in the nucleolus. The first occurred during the zygotene-pachytene stage and the second (not previously described in plant meiocytes) in the diplotene. These processes correlated with a considerable increase in nucleolus volume during these periods. At the end of the zygotene, several perinucleolar structures lying close to each other and containing rRNA, argyrophilic proteins, U3 small nucleolar RNA, and fibrillarin were observed. The occurrence of newly formed RNA was also observed in these structures. This suggests that the observed perinucleolar structures correspond to the additional nucleoli known from animals.

Preferences for aspects of a dermatology consultation

BACKGROUND

General practitioners with special interests (GPSIs) are increasingly being used to provide dermatology services in the U.K. Little is known about U.K. dermatology patient attitudes to proposed variations in secondary care service delivery or the values they attach to aspects of the care they receive.

OBJECTIVES

To quantify preferences for different attributes of care within dermatology secondary care services.

METHODS

Attributes of care that are important to dermatology patients were derived using in-depth qualitative interviews with 19 patients at different points in the care pathway. A discrete choice experiment using 'best-worst scaling' was sent by post to 119 patients referred to secondary care dermatology services and suitable for GPSI care who had agreed to participate in research.

RESULTS

Four attributes were derived from the qualitative work: waiting, expertise, thorough care and convenience. For the discrete choice experiment, 99 patients returned questionnaires, 93 of which contained sufficient data for analysis. All attributes were found to be quantitatively important. The attribute of greatest importance was expertise of the doctor, while waiting time was of least importance. Respondents were willing to wait longer than the current 3 months maximum to receive care that was thorough, 2.1 months to see a team led by an expert and 1.3 months to attend a consultation that is easy to get to.

CONCLUSIONS

Although the need to reduce outpatient waiting times is a key policy driver behind the expansion of GPSI services, this does not appear to be the most important issue for patients. The thoroughness with which the consultation is provided and the expertise of the clinician seen are higher priorities.