675 research outputs found

    Assessing the fidelity of marine vertebrate microfossil δ18O signatures and their potential for palaeo-ecological and -climatic reconstructions

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    Conodont biogenic apatite has become a preferred analytical target for oxygen isotope studies investigating ocean temperature and palaeoclimate changes in the Palaeozoic. Despite the growing application in geochemically-based palaeoenvironmental reconstructions, the paucity or absence of conodont fossils in certain facies necessitates greater flexibility in selection of robust oxygen-bearing compounds for analysis. Vertebrate microfossils (teeth, dermal denticles, spines) offer a potential substitute for conodonts from the middle Palaeozoic. Vertebrate bioapatite is particularly advantageous given a fossil record extending to the present with representatives across freshwater to fully marine environments, thus widening the scope of oxygen isotope studies on bioapatite. However, significant tissue heterogeneity within vertebrates and differential susceptibility of these tissues to diagenetic alteration have been raised as potential problems affecting the reliability of the oxygen isotope ratios as palaeoclimatic proxies. Well-preserved vertebrate microfossils and co-occurring conodont fossils from the Upper Devonian and Lower Carboniferous of the Lennard Shelf, Canning Basin, Western Australia, were analysed using bulk (gas isotope ratio mass spectrometry, GIRMS) and in-situ (secondary ion mass spectrometry, SIMS) methodologies, with the latter technique allowing investigation of specific tissues within vertebrate elements. The d18Oconodont results may be interpreted in terms of palaeolatitudinally and environmentally sensible palaeo-salinity and -temperature and provide a baseline standard for comparison against vertebrate microfossil d18O values. Despite an absence of obvious diagenetic modification, GIRMS of vertebrate denticles yielded d18O values depleted in 18O by 2–4‰ relative to co-occurring conodonts. SIMS analysis of dentine tissues exhibited significant heterogeneity, while hypermineralised tissues in both scales and teeth produced d18O values comparable with those of associated conodonts. The susceptibility of permeable phosphatic fossil tissues to microbial activity, fluid interaction and introduction of mineral precipitates post-formation is demonstrated in the dentine of vertebrate microfossils, which showed significant heterogeneity and consistent depletion in 18O relative to conodonts. The hypermineralised tissues present in both teeth and scales appear resistant to many diagenetic processes and indicate potential for palaeoclimatic reconstructions and palaeoecological investigations

    Immediate chest X-ray for patients at risk of lung cancer presenting in primary care: randomised controlled feasibility trial

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    Background: Achieving earlier stage diagnosis is one option for improving lung cancer outcomes in the United Kingdom. Patients with lung cancer typically present with symptoms to general practitioners several times before referral or investigation. Methods: We undertook a mixed methods feasibility individually randomised controlled trial (the ELCID trial) to assess the feasibility and inform the design of a definitive, fully powered, UK-wide, Phase III trial of lowering the threshold for urgent investigation of suspected lung cancer. Patients over 60, with a smoking history, presenting with new chest symptoms to primary care, were eligible to be randomised to intervention (urgent chest X-ray) or usual care. Results: The trial design and materials were acceptable to GPs and patients. We randomised 255 patients from 22 practices, although the proportion of eligible patients who participated was lower than expected. Survey responses (89%), and the fidelity of the intervention (82% patients X-rayed within 3 weeks) were good. There was slightly higher anxiety and depression in the control arm in participants aged >75. Three patients (1.2%) were diagnosed with lung cancer. Conclusions: We have demonstrated the feasibility of individually randomising patients at higher risk of lung cancer, to a trial offering urgent investigation or usual care

    Mutual aid groups in psychiatry and substance misuse

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    Background: Mutuality is a feature of many ‘self-help groups’ for people with mental health and/or substance misuse needs. These groups are diverse in terms of membership, aims, organisation and resources. Collectively, in terms of the pathways for seeking help, support, social capital or simply validation as people, mutual aid groups figure at some time in the life story of many psychiatric and/or substance misuse patients. From the viewpoint of clinical services, relations with such groups range from formal collaboration, through incidental shared care, via indifference, to incomprehension, suspicion, or even hostility. How should mental health and substance misuse clinicians relate to this informal care sector, in practice? Aims: To synthesise knowledge about three aspects of the relationship between psychiatric/substance misuse services and mutual aid groups: profile groups' engagement of people with mental health and/or substance misuse needs at all stages of vulnerability, illness or recovery; characterise patterns of health benefit or harm to patients, where such outcome evidence exists; identify features of mutual aid groups that distinguish them from clinical services. Method: A search of both published and unpublished literature with a focus on reports of psychiatric and substance misuse referral routes and outcomes, compiled for meta-synthesis. Results: Negative outcomes were found occasionally, but in general mutual aid group membership was repeatedly associated with positive benefits. Conclusions: Greater awareness of this resource for mental health and substance misuse fields could enhance practice

    Effects of demand-side financing on utilisation, experiences and outcomes of maternity care in low- and middle-income countries: a systematic review.

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    Demand-side financing, where funds for specific services are channelled through, or to, prospective users, is now employed in health and education sectors in many low- and middle-income countries. This systematic review aimed to critically examine the evidence on application of this approach to promote maternal health in these settings. Five modes were considered: unconditional cash transfers, conditional cash transfers, short-term payments to offset costs of accessing maternity services, vouchers for maternity services, and vouchers for merit goods. We sought to assess the effects of these interventions on utilisation of maternity services and on maternal health outcomes and infant health, the situation of underprivileged women and the healthcare system

    Recommendations from the European Working Group for Value Assessment and Funding Processes in Rare Diseases (ORPH-VAL)

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    International audienceAbstractRare diseases are an important public health issue with high unmet need. The introduction of the EU Regulation on orphan medicinal products (OMP) has been successful in stimulating investment in the research and development of OMPs. Despite this advancement, patients do not have universal access to these new medicines. There are many factors that affect OMP uptake, but one of the most important is the difficulty of making pricing and reimbursement (P&R) decisions in rare diseases. Until now, there has been little consensus on the most appropriate assessment criteria, perspective or appraisal process. This paper proposes nine principles to help improve the consistency of OMP P&R assessment in Europe and ensure that value assessment, pricing and funding processes reflect the specificities of rare diseases and contribute to both the sustainability of healthcare systems and the sustainability of innovation in this field. These recommendations are the output of the European Working Group for Value Assessment and Funding Processes in Rare Diseases (ORPH-VAL), a collaboration between rare disease experts, patient representatives, academics, health technology assessment (HTA) practitioners, politicians and industry representatives. ORPH-VAL reached its recommendations through careful consideration of existing OMP P&R literature and through a wide consultation with expert stakeholders, including payers, regulators and patients. The principles cover four areas: OMP decision criteria, OMP decision process, OMP sustainable funding systems and European co-ordination. This paper also presents a guide to the core elements of value relevant to OMPs that should be consistently considered in all OMP appraisals. The principles outlined in this paper may be helpful in drawing together an emerging consensus on this topic and identifying areas where consistency in payer approach could be achievable and beneficial. All stakeholders have an obligation to work together to ensure that the promise of OMP’s is realised

    Non-steroidal Anti-inflammatory Drug (NSAID)-, Potassium Supplement-, Bisphosphonate-, and Doxycycline-Mediated Peptic Ulcer Effects: A Narrative Review

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    Peptic ulcers are a common condition that arises from an imbalance between acid production and gastroduodenal protective factors. Various drugs, including non-steroidal anti-inflammatory drugs (NSAIDs), potassium supplements, bisphosphonates, and doxycycline, can increase the development of peptic ulcers. NSAIDs are one of the most common medications prescribed for pain relief, and they also inhibit the formation of cyclooxygenase-1 (COX-1). COX-1 helps in the production of mucus that lines the stomach, so by inhibiting COX-1, NSAIDs reduce the mucus produced by the stomach and increase the likelihood of gastric ulcer formation. Additionally, NSAIDs are acidic, and increasing the amount of any acid in the stomach can result in promoting ulcer development. Potassium supplements are used to reduce the effects of hypertension, decrease the development of kidney stones, and treat hypokalemia. The various types of transporters and channels used to move potassium across cell membranes increase hydrogen being pumped, increasing gastric acid production and ulcer formation. Bisphosphonates are used to treat a variety of skeletal disorders that require inhibition of osteoclast activity. Nitric oxide (NO) has been shown to have a therapeutic effect on gastric ulcers, and some bisphosphonates have been shown to decrease the production of nitric oxide, resulting in increased damage to the gastric mucosa. Finally, doxycycline is a broad-spectrum tetracycline antibiotic that is typically used to treat anthrax poisoning, skin lesions, and sexually transmitted diseases. A harmful adverse effect of doxycycline is the formation of peptic and gastric ulcers related to the drug being highly acidic once it has dissolved

    Bayesian inference reveals positive but subtle effects of experimental fishery closures on marine predator demographics

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    Global forage-fish landings are increasing, with potentially grave consequences for marine ecosystems. Predators of forage fish may be influenced by this harvest, but the nature of these effects is contentious. Experimental fishery manipulations offer the best solution to quantify population-level impacts, but are rare. We used Bayesian inference to examine changes in chick survival, body condition and population growth rate of endangered African penguins Spheniscus demersus in response to 8 years of alternating time-area closures around two pairs of colonies. Our results demonstrate that fishing closures improved chick survival and condition, after controlling for changing prey availability. However, this effect was inconsistent across sites and years, highlighting the difficultly of assessing management interventions in marine ecosystems. Nevertheless, modelled increases in population growth rates exceeded 1% at one colony; i.e. the threshold considered biologically meaningful by fisheries management in South Africa. Fishing closures evidently can improve the population trend of a forage-fish-dependent predator-we therefore recommend they continue in South Africa and support their application elsewhere. However, detecting demographic gains for mobile marine predators from small no-take zones requires experimental time frames and scales that will often exceed those desired by decision makers
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