2,056 research outputs found

    Development and application of an assay for uranyl complexation by fungal metabolites, including siderophores

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    An assay to detect UO2 2+ complexation was developed based on the chrome azurol S (CAS) assay for siderophores (B. Schwyn and J. B. Neilands, Anal. Biochem. 160:47-56, 1987) and was used to investigate the ability of fungal metabolites to complex actinides. In this assay the discoloration of two dyed agars (one containing a CAS-Fe3+ dye and the other containing a CAS-UO2 2+ dye) caused by ligands was quantified. The assay was tested by using the siderophore desferrioxamine B (DFO), and the results showed that there was a regular, reproducible relationship between discoloration and the amount of siderophore added. The ratio of the discoloration on the CAS-UO2 2+ agar to the discoloration on the CAS-Fe3+ agar was independent of the amount of siderophore added. A total of 113 fungi and yeasts were isolated from three soil samples taken from the Peak District National Park. The fungi were screened for the production of UO2 2+ chelators by using the CAS-based assay and were also tested specifically for hydroxamate siderophore production by using the hydroxamate siderophore auxotroph Aureobacterium flavescens JG-9. This organism is highly sensitive to the presence of hydroxamate siderophores. However, the CAS-based assay was found to be less sensitive than the A. flavescens JG-9 assay. No significant difference between the results for each site for the two tests was found. Three isolates were selected for further study and were identified as two Pencillium species and a Mucor species. Our results show that the new assay can be effectively used to screen fungi for the production of UO2 2+ chelating ligands. We suggest that hydroxamate siderophores can be produced by mucoraceous fungi

    Enhancing the experience of carers in the chemotherapy outpatient setting: an exploratory randomised controlled trial to test impact, acceptability and feasibility of a complex intervention co-designed by carers and staff

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    PurposeSupporting someone through chemotherapy can be emotionally and physically demanding. However, research has yet to establish the type of support carers require or the best way to provide this. This study tested the feasibility and acceptability of a complex intervention for carers that was co-designed by staff and carers of patients starting chemotherapy.MethodsForty-seven carers were recruited, randomised between the intervention (n?=?24) and control (n?=?23) groups. A questionnaire was completed pre- and post-intervention measuring knowledge of chemotherapy and its side effects, experience of care, satisfaction with outpatient services, coping and emotional wellbeing. The intervention process was evaluated by carers and healthcare professionals (HCPs) in focus groups.ResultsRecruitment to the study was unproblematic and attrition from it was low, suggesting the intervention and study processes were acceptable to patients and carers. Carers in receipt of the ‘Take Care’ intervention reported statistically significantly better understanding of symptoms and side effects and their information needs being more frequently met than carers in the control. Confidence in coping improved between baseline and follow-up for the intervention group and declined for the control although differences were insufficient to achieve statistical significance. There was no significant difference between the two groups’ emotional wellbeing. HCP and carer focus groups confirmed the feasibility and acceptability of the intervention.ConclusionsThe ‘Take Care’ intervention proved acceptable to carers and HCPs and demonstrates considerable promise and utility in practice. Study findings support the conduct of a fully powered RCT to determine the intervention’s effectiveness and cost-effectiveness

    Magnetic Oculomotor Prosthetics for Acquired Nystagmus

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    PURPOSE: Acquired nystagmus, a highly symptomatic consequence of damage to the substrates of oculomotor control, often is resistant to pharmacotherapy. Although heterogeneous in its neural cause, its expression is unified at the effector-the eye muscles themselves-where physical damping of the oscillation offers an alternative approach. Because direct surgical fixation would immobilize the globe, action at a distance is required to damp the oscillation at the point of fixation, allowing unhindered gaze shifts at other times. Implementing this idea magnetically, herein we describe the successful implantation of a novel magnetic oculomotor prosthesis in a patient. DESIGN: Case report of a pilot, experimental intervention. PARTICIPANT: A 49-year-old man with longstanding, medication-resistant, upbeat nystagmus resulting from a paraneoplastic syndrome caused by stage 2A, grade I, nodular sclerosing Hodgkin's lymphoma. METHODS: We designed a 2-part, titanium-encased, rare-earth magnet oculomotor prosthesis, powered to damp nystagmus without interfering with the larger forces involved in saccades. Its damping effects were confirmed when applied externally. We proceeded to implant the device in the patient, comparing visual functions and high-resolution oculography before and after implantation and monitoring the patient for more than 4 years after surgery. MAIN OUTCOME MEASURES: We recorded Snellen visual acuity before and after intervention, as well as the amplitude, drift velocity, frequency, and intensity of the nystagmus in each eye. RESULTS: The patient reported a clinically significant improvement of 1 line of Snellen acuity (from 6/9 bilaterally to 6/6 on the left and 6/5-2 on the right), reflecting an objectively measured reduction in the amplitude, drift velocity, frequency, and intensity of the nystagmus. These improvements were maintained throughout a follow-up of 4 years and enabled him to return to paid employment. CONCLUSIONS: This work opens a new field of implantable therapeutic devices-oculomotor prosthetics-designed to modify eye movements dynamically by physical means in cases where a purely neural approach is ineffective. Applied to acquired nystagmus refractory to all other interventions, it is shown successfully to damp pathologic eye oscillations while allowing normal saccadic shifts of gaze

    Death within 8 years after childhood convulsive status epilepticus:a population-based study

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    The risk of long-term mortality and its predictors following convulsive status epilepticus in childhood are uncertain. We report mortality within 8 years after an episode of convulsive status epilepticus, and investigate its predictors from a paediatric, prospective, population-based study from north London, UK. In the current study, we followed-up a cohort previously ascertained during a surveillance study of convulsive status epilepticus in childhood. After determining the survival status of the cohort members, we defined cause of death as that listed on their death certificates. We estimated a standardized mortality ratio to compare mortality in our cohort with that expected in the reference population. Multivariable Cox regression analysis was used to investigate any association between the clinical and demographic factors at the time of status epilepticus and subsequent risk of death. The overall case fatality was 11% (95% confidence interval 7.5–16.2%); seven children died within 30 days of their episode of convulsive status epilepticus and 16 during follow-up. The overall mortality in our cohort was 46 times greater than expected in the reference population, and was predominantly due to higher mortality in children who had pre-existing clinically significant neurological impairments when they had their acute episode of convulsive status epilepticus. Children without prior neurological impairment who survived their acute episode of convulsive status epilepticus were not at a significantly increased risk of death during follow-up. There were no deaths in children following prolonged febrile convulsions and idiopathic convulsive status epilepticus. A quarter of deaths during follow-up were associated with intractable seizures/convulsive status epilepticus, and the rest died as a complication of their underlying medical condition. On regression analysis, presence of clinically significant neurological impairments prior to convulsive status epilepticus was the only independent risk factor for mortality. In conclusion, there is a high risk of death within 8 years following childhood convulsive status epilepticus but most deaths are not seizure related. Presence of pre-existing clinically significant neurological impairments at the time of convulsive status epilepticus is the main risk factor for mortality within 8 years after the acute episode. The attributable role of convulsive status epilepticus on mortality remains uncertain, but appears less than is generally perceived

    Scans for signatures of selection in Russian cattle breed genomes reveal new candidate genes for environmental adaptation and acclimation

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    Domestication and selective breeding has resulted in over 1000 extant cattle breeds. Many of these breeds do not excel in important traits but are adapted to local environments. These adaptations are a valuable source of genetic material for efforts to improve commercial breeds. As a step toward this goal we identified candidate regions to be under selection in genomes of nine Russian native cattle breeds adapted to survive in harsh climates. After comparing our data to other breeds of European and Asian origins we found known and novel candidate genes that could potentially be related to domestication, economically important traits and environmental adaptations in cattle. The Russian cattle breed genomes contained regions under putative selection with genes that may be related to adaptations to harsh environments (e.g., AQP5, RAD50, and RETREG1). We found genomic signatures of selective sweeps near key genes related to economically important traits, such as the milk production (e.g., DGAT1, ABCG2), growth (e.g., XKR4), and reproduction (e.g., CSF2). Our data point to candidate genes which should be included in future studies attempting to identify genes to improve the extant breeds and facilitate generation of commercial breeds that fit better into the environments of Russia and other countries with similar climates

    Lamotrigine for people with borderline personality disorder: a RCT

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    Background: No drug treatments are currently licensed for the treatment of borderline personality disorder (BPD). Despite this, people with this condition are frequently prescribed psychotropic medications and often with considerable polypharmacy. Preliminary studies have indicated that mood stabilisers may be of benefit to people with BPD. Objective: To examine the clinical effectiveness and cost-effectiveness of lamotrigine for people with BPD. Design: A two-arm, double-blind, placebo-controlled individually randomised trial of lamotrigine versus placebo. Participants were randomised via an independent and remote web-based service using permuted blocks and stratified by study centre, the severity of personality disorder and the extent of hypomanic symptoms. Setting: Secondary care NHS mental health services in six centres in England. Participants: Potential participants had to be aged ≥ 18 years, meet diagnostic criteria for BPD and provide written informed consent. We excluded people with coexisting psychosis or bipolar affective disorder, those already taking a mood stabiliser, those who spoke insufficient English to complete the baseline assessment and women who were pregnant or contemplating becoming pregnant. Interventions: Up to 200 mg of lamotrigine per day or an inert placebo. Women taking combined oral contraceptives were prescribed up to 400 mg of trial medication per day. Main outcome measures: Outcomes were assessed at 12, 24 and 52 weeks after randomisation. The primary outcome was the total score on the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) at 52 weeks. The secondary outcomes were depressive symptoms, deliberate self-harm, social functioning, health-related quality of life, resource use and costs, side effects of treatment and adverse events. Higher scores on all measures indicate poorer outcomes. Results: Between July 2013 and October 2015 we randomised 276 participants, of whom 195 (70.6%) were followed up 52 weeks later. At 52 weeks, 49 (36%) of those participants prescribed lamotrigine and 58 (42%) of those prescribed placebo were taking it. At 52 weeks, the mean total ZAN-BPD score was 11.3 [standard deviation (SD) 6.6] among those participants randomised to lamotrigine and 11.5 (SD 7.7) among those participants randomised to placebo (adjusted mean difference 0.1, 95% CI –1.8 to 2.0; p = 0.91). No statistically significant differences in secondary outcomes were seen at any time. Adjusted costs of direct care for those prescribed lamotrigine were similar to those prescribed placebo. Limitations: Levels of adherence in this pragmatic trial were low, but greater adherence was not associated with better mental health. Conclusions: The addition of lamotrigine to the usual care of people with BPD was not found to be clinically effective or provide a cost-effective use of resources. Future work: Future research into the treatment of BPD should focus on improving the evidence base for the clinical effectiveness and cost-effectiveness of non-pharmacological treatments to help policy-makers make better decisions about investing in specialist treatment services

    Going DEEP: an evaluation of a social pedagogy-informed approach to evidence-enriched practice in social care

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    Social care workers benefit from multiple types of evidence to enhance citizen well-being, support their own well-being and improve social care services. Building capacity within social care to find, collect and use different forms of evidence is an international concern. The Developing Evidence Enriched Practice (DEEP) programme in Wales is informed by the values and aims of social pedagogy. It aspires to enhance both the generation and use of evidence in social care. To learn about what works in the programme, we conducted an evaluation based on contribution analysis that explored programme impacts between 2020 and 2023. Based on a co-produced theory of change the evaluation drew on exemplar cases, questionnaire responses, documentary evidence, process data and unsolicited feedback. There was evidence that the DEEP programme contributed to people better valuing and gaining a better understanding of different forms of evidence. Citizen voice could become more central in decision-making, and there were examples of practice, policy and research being informed by diverse evidence. Many people who attended the DEEP learning course enhanced their confidence and skills by using the DEEP approach and said that they would put their learning into practice. It was harder to evidence longer-term impacts and the sustainability of the approach. These findings suggest that there can be merit in developing capacity-building programmes informed by social pedagogy. Such programmes can be characterised as relational, holistic, practice-focused, multifaceted, contextualised and co-produced with intended beneficiaries

    HACE1 deficiency causes an autosomal recessive neurodevelopmental syndrome

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    Background: The genetic etiology of neurodevelopmental defects is extremely diverse, and the lack of distinctive phenotypic features means that genetic criteria are often required for accurate diagnostic classification. We aimed to identify the causative genetic lesions in two families in which eight affected individuals displayed variable learning disability, spasticity and abnormal gait. Methods: Autosomal recessive inheritance was suggested by consanguinity in one family and by sibling recurrences with normal parents in the second. Autozygosity mapping and exome sequencing, respectively, were used to identify the causative gene. Results: In both families, biallelic loss-of-function mutations in HACE1 were identified. HACE1 is an E3 ubiquitin ligase that regulates the activity of cellular GTPases, including Rac1 and members of the Rab family. In the consanguineous family, a homozygous mutation p.R219* predicted a truncated protein entirely lacking its catalytic domain. In the other family, compound heterozygosity for nonsense mutation p.R748* and a 20-nt insertion interrupting the catalytic HECT domain was present; Western analysis of patient cells revealed an absence of detectable HACE1 protein. Conclusion: HACE1 mutations underlie a new autosomal recessive neurodevelopmental disorder. Previous studies have implicated HACE1 as a tumour suppressor gene; however, since cancer predisposition was not observed either in homozygous or heterozygous mutation carriers, this concept may require re-evaluation

    Modeling the Effects of Doliolids on the Plankton Community Structure of the Southeastern US Continental Shelf

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    A model of the lower trophic levels that consists of a system of coupled ordinary differential equations was developed to investigate the time-dependent behavior of doliolid populations associated with upwelling features on the outer southeastern US continental shelf. Model equations describe the interactions of doliolids with two phytoplankton size fractions, five copepod developmental stages and a detrital pool. Additional equations describe nitrate and ammonia. Model dynamics are based primarily upon data obtained from field and laboratory experiments for southeastern US continental shelf plankton populations. Variations on a reference simulation, which represents average upwelling conditions without doliolids, were carried out to determine the effect of inclusion of doliolids, temperature and nutrient variations, and variations in ambient food concentrations on the basic plankton community structure. These simulations provide a measure of the role of environmental versus biological interactions in structuring the planktonic food web on the southeastern US continental shelf. Simulations show that the copepod population is significantly reduced when doliolids are present. This happens primarily as a result of direct predation of the doliolids on copepod eggs and juveniles as opposed to an increase in competition for phytoplankton, the primary food source. Additional simulations show that the cooler temperatures associated with the newly upwelled water temporarily decrease the growth rates of the doliolids and copepods, bestowing an even greater advantage on the rapidly reproducing doliolids
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