Recent Developments in Fisheries Science and Their Prospects for Improving Fisheries Contributions to Food Security

Marine reserves, areas permanently closed to all fishing, are frequently proposed as a tool for managing fisheries. Fishery benefits claimed for reserves include increases in spawning stock size, animal body size, and reproductive output of exploited species. Reserves are predicted to augment catches through export of offspring to fishing grounds, and spillover of juveniles and adults from reserves to fisheries. Protection of stocks and development of extended age structures of populations in reserves are argued to offer insurance against environmental variability and management failure. Models also suggest reserves will reduce year-to-year variability in catches, and offer greater simplicity of management and enforcement. Reserves are predicted to lead to habitat recovery from fishing disturbance which can also enhance benefits to fisheries. Extensive field research confirms many of these predictions. Reserves worldwide have led to increases in abundance, body size, biomass and reproductive output of exploited species. Such measures often increase many times over, sometimes by an order of magnitude or more. Population build up is usually rapid with effects detectable within 2-3 years of protection. Increases are often sustained over extended periods, particularly for longer-lived species and for measures of habitat recovery. Reserves have benefitted species from a wide taxonomic spectrum that covers most economically important taxa, including many species of fish, crustaceans, mollusks and echinoderms. Encouraged by these results, many countries and states have embarked upon initiatives to establish networks of marine reserves. However, reserves remain highly controversial among fishers and fishing industry bodies who argue that fishery benefits remain unproven. In the last three years there has been rapid growth in the number of cases where fisheries have been shown to benefit from reserves. In this report, we critically analyze this body of evidence, drawing upon studies of reserves and fishery closures. Fishery managers have long used fishery closures, areas temporarily closed to fishing for one or more species or to specific fishing gears. They are employed to help rebuild depleted stocks, reduce gear conflicts, protect vulnerable life stages of exploited species or protect sensitive habitats from damaging gears. Such areas can tell us much about the potential effects of marine reserves. Fishery benefits from reserves and fishery closures typically develop quickly, in most cases within five years of their creation. Perhaps the most persuasive evidence of fishery effects of reserves comes from changing fishing patterns. In most places where well-respected reserves or fishery closures exist, fishers tend to move their fishing activities closer to their boundaries. Fishing-the-line, as it is called, allows fishers to benefit from spillover of animals from reserves to fishing grounds. There are now well-documented cases of spillover from more than a dozen countries and including a wide range of species. It is more technically demanding to prove fishery enhancement through export of offspring on ocean currents. Existing reserves are generally small, making it hard to detect increased recruitment to fisheries at a regional scale. However, there are now several cases in which export of eggs and larvae have been confirmed, including dramatic enhancement of scallop fisheries in Georges Bank and clam fisheries in Fiji. Small reserves have worked well and repeatedly produce local benefits. However, regional fisheries enhancement will require more extensive networks of reserves. Some of the most convincing success stories come from places in which between 10 and 35% of fishing grounds have been protected. In several cases there is evidence that yields with reserves have risen to higher levels than prior to protection, despite a reduction in the area of fishing grounds. In other cases, smaller reserves have stabilized catches from intensively exploited fisheries or slowed existing rates of decline. We describe experiences that prove that success of marine reserves is not contingent on habitat type, geographical location, the kind of fishery involved, or the technological sophistication of management. Reserve benefits are not restricted to habitats like coral reefs, or to artisanal fisheries, as some critics claim. Fishery benefits have been demonstrated from reserves established in tropical, warm- and cold-temperate waters, and in many habitats, including coral reefs, rocky reefs, kelp forests, seagrass beds, mangroves, estuaries, soft sediments, continental shelves and deep sea. Reserves and fishery closures have worked well for a wide range of fisheries, spanning recreational fisheries, artisanal fisheries like those of coral reefs, through small-scale nearshore fisheries for species like lobsters, up to industrial-scale fisheries for animals like flatfish and scallops. They have worked across a similarly broad spectrum of management sophistication, from self-policing by committed fishers, through warden patrols to satellite monitoring of distant fishing activities. We now have strong evidence that with the support of local communities, marine reserves offer a highly effective management tool. However, reserves will only rarely be adequate as a stand-alone management approach, although we describe cases where they have worked in the absence of other measures. They will be most effective when implemented as part of a package of limits on fishing effort and protect exploited species and their habitats

Development of an outcome measure to assess performance of physiotherapy cardiorespiratory skills: A Delphi Study

Current evidence regarding high-fidelity simulation (HFS) in physiotherapy education focuses on student perceptions producing very positive responses from students. HFS has the potential to improve skill performance and consequently better prepare students for gaining the best learning from clinical placement, but it is an expensive teaching method. Before the impact of HFS can be investigated, a valid and reliable tool to assess skill performance is required. The purpose of this study is to develop such a tool in order to assess student competency in core cardiorespiratory skills. The study implemented a Delphi method - a method of gaining convergence of opinion. Using pre-defined criteria, cardiorespiratory experts were identified and invited to participate. They were sent a questionnaire that used open questions in order to identify participants' expectations of students, in relation to core respiratory physiotherapy assessment and treatment techniques. Data from the first questionnaire ('round one') were analysed and used to generate the questionnaire for round two, in which participants were asked to indicate their level of agreement with various statements using Likert scales. The second round focused on: explanations about techniques to patients; instructions given prior to- and during techniques; hand positions used; positioning of patients, and; safety considerations. Round three will further clarify outstanding aspects, prior to the development of a draft outcome measure - this will then be circulated for comment in round four. The study will use the content validity index to calculate levels of agreement with statements in round four. In terms of results so far, there was a 31% (6/13) response rate for round one, representing Australia, Canada and the UK. Sixteen further panelists were identified for round two, following a search of staff lists and biographies from universities in all three countries. The response rate for round two was 51% (15/29), and round three is currently underway. The conference presentation will summarise conclusions from the study alongside presenting the outcome measure, ready for testing to establish its reliability and validity

TRACE METALS IN BLOOD AND URINE AS POTENTIAL MARKERS OF BONE BREAKDOWN IN PATIENTS WITH BONE METASTASES

In the western world cancer is the second most important cause of death, after heart disease, accounting for 20-25% of all mortalities, and is today probably one of the most feared diseases. Approximately one third of all cancer patients will develop skeletal metastases (secondary bone cancer). Early diagnosis and effective monitoring during treatment is therefore essential in terms of making any impact on survival rates and developing new cancer therapies. Unfortunately, the current methods for diagnosing and measuring bone metastases, such as bone scans and urinary hydroxyproline determinations, lack sensitivity and specificity. The urinary pyridinium crosslinks, pyridinoline (PYD) and deoxypyridinoline (DPYD), have recently been identified as sensitive and specific markers of bone breakdown. However the analysis of the pyridinium crosslinks using high performance liquid chromatography (HPLC) has proved far from ideal for routine clinical assessment. The results from studies to critically evaluate this method are presented and particular problems encountered when the crosslinks are extracted from the urine samples are discussed. The tedious, time consuming and cumbersome sample preparation procedure are also shown to adversely effect the robustness and reproducibility of the method. The recent introduction of an immunoassay method potentially overcomes many of the inherent problems with the HPLC analysis. This enzyme linked immunoasorbant assay (ELISA) is evaluated and found to compare favourably with the HPLC method, offering several distinct advantages. The method is quick, simple, robust, demonstrates good accuracy and precision, is less prone to interferences and can be easily introduced into clinical laboratories on a routine basis. In addition it also minimises sample preparation time. However, there is still a requirement for alternative and better biochemical markers to measure bone breakdown. It is well known that bone is an active, living tissue and that bone metabolism and remodelling are tightly coupled processes, where the rate of bone formation equals the rate of bone resorption in healthy bone. When an imbalance occurs, this leads to unhealthy bone and ultimately a clinical disease of the skeleton. Some trace metals, e.g lead, accumulate in the bone and since the development of bone metastases results in extensive bone breakdown, the subsequent release of these metals into the blood and urine may potentially serve as markers. In this work inductively coupled plasma-mass spectrometry (ICP-MS) has been used and methods developed to determine such metals in clinical matrices. The development of a simple dilution method is described for use in preliminary trials to measure the blood lead levels and other trace metal profiles, in patients with bone metastases. The blood lead results attained agree closely with a certified reference material, and the method is shown to remain under analytical control. The trial results are presented and discussed with reference to further and more detailed investigations. The selection criteria for other suitable elements such as AI, Ba, Cd, Ce, Pb, Sr, and Zr in blood and urine, along with an assessment of the analytical and clinical praticalities of the methodology which must be considered for subsequent full clinical trials is also discussed following a critical evaluation. Finally the results obtained in a extended clinical trial are presented. The crosslink levels (serving as the reference marker), measured by ELISA, were compared with the trace metal levels (Cd, Pb and Sr) in blood and urine samples, measured by ICP-MS, in order to assess their diagnostic potential and effectiveness in monitoring treatment. The blood lead levels were found to offer the greatest potential, correlating well with the DPYD values in the majority of cases. The blood strontium levels also showed some promise. However the blood cadmium and the urinary trace metal levels proved less suitable. The results attained in this feasibility study support a more detailed clinical investigation, on a much larger scale, and over a longer period of time. The need to incorporate a full statistical evaluation of all factors that can influence the final results is highlighted.Freedom Fields Hospital, Plymout

Development of a tool to assess core cardiorespiratory physiotherapy skills: a Delphi study.

Purpose: This study reports on the development of an outcome measure designed to evaluate pre-registration physiotherapy students’ ability in performing core cardiorespiratory skills. Method: A four round, e-Delphi study using an international panel of expert cardiorespiratory physiotherapists involved in pre-registration student education was undertaken. In round one participants identified what they look for in students competently performing core cardio-respiratory physiotherapy assessment and treatment skills. These items were refined in rounds two and three. Item content validity score (iCVI) of ≥ 0.8 at round four identified consensus. Scale content validity index (SCVI) was calculated. Results: Response rate for round one was 46% (6/13). Additional experts were invited to participate and response rates increased to 71% (round 2), 88% (round 3) and 100% (round 4). Of the 207 items across the seven skills identified in round one, 140 were presented in round four. Of these, consensus was achieved for 128 items, with 12 being excluded. The SCVI was 0.907. Conclusion: This e-Delphi study enabled the development of a draft outcome measure, which aims to assess performance of seven cardiorespiratory physiotherapy skills. This tool will enable rigorous evaluation of different education methods to establish their effectiveness. However, it is first necessary to establish construct validity and assess inter and intra-rater reliability

Effectiveness of expiratory muscle strength training on expiratory strength, pulmonary function and cough in the adult population: a systematic review.

Background: Respiratory muscle strength declines in certain disease states, leading to impaired cough, reduced airway clearance and an increased risk of aspiration pneumonia. Respiratory muscle training may therefore reduce this risk. Objectives: To assess current evidence of expiratory muscle strength training (EMST) on maximum expiratory pressure, cough flow and spirometry. Data sources: Databases including CINAHL, Medline, Science Direct and PEDRo were searched. Eligibility Criteria: Randomised controlled trials investigating expiratory muscle strength training on maximum expiratory pressure, pulmonary function or cough in any adult population, published before December 2017. Study appraisal: Data were extracted to a trial description form and study quality evaluated by 2 reviewers. Meta-analysis was performed with calculation of mean differences and 95% confidence intervals. Results: Nine studies met inclusion criteria and ranged in size from 12 to 42 participants. Trials investigated EMST in healthy adults (2), multiple sclerosis (3), COPD (2), acute stroke (1) and spinal cord injury (1). Overall, EMST improved maximum expiratory pressure (15.95cmH2O; 95% CI: 7.77 to 24.12; P [less than] 0.01) with no significant impact on cough flow (4.63 L/minute; 95%CI −27.48 to 36.74; P = 0.78), forced vital capacity (−0.16 L; 95%CI −0.35 to 0.02; P = 0.09) or forced expiratory volume in 1 second (−0.09 L; 95%CI −0.10 to −0.08; P [less than] 0.001) vs control or sham training. Conclusions: Meta-analysis indicated a small significant increase in maximum expiratory pressure following EMST. Improvements in maximum expiratory pressure did not lead to improvements in cough or pulmonary function. Limitations: Variations in protocol design and population limited the overall effect size

Impact of simulated patients on physiotherapy students' skill performance in cardiorespiratory practice classes: a pilot study.

Purpose: To date, no evidence exists that high-fidelity simulation improves skill development among physiotherapy students in the university setting. With pressures to reduce costs and maintain or improve the quality of the learning experience, and with pressures on clinical placement, it is essential to investigate methods that might improve students’ skill performance before they undertake clinical practice. Our study set out to investigate (1) the impact of using simulated patients (SPs) in a practical class on physiotherapy students’ skill acquisition and (2) the students’ reflections on the intervention. Method: We devised a pilot study using a single-centre randomized controlled trial. A total of 28 undergraduate physiotherapy students, matched using previous practical examination grades, undertook a 2-hour practical class in which they practised their core cardiorespiratory skills. Pre-session resources were identical. The control group practised on peers; the intervention group practised on SPs. The students’ skill performance was assessed 2 weeks later using the Mini-Clinical Evaluation Exercise (MiniCEX), including gathering qualitative data from the students’ reflections. Twenty-eight students undertook the practical class and subsequent MiniCEX assessment. Results: A statistically significant difference was found for all aspects of the MiniCEX except medical interview ( p = 0.07) and physical interview (p = 0.69), and a large effect size was found for all areas except physical interview (0.154) and medical interview (0.378). The students’ reflections focused on three key themes: behaviours and attitudes, teaching the active cycle of breathing technique, and feedback. Conclusions: Our findings suggest that interacting with SPs improves student skill performance, but further research using a larger sample size and an outcome measure validated for this population is required to confirm this

Molecular basis for resistance of acanthamoeba tubulins to all major classes of antitubulin compounds

Tubulin is essential to eukaryotic cells and is targeted by several antineoplastics, herbicides, and antimicrobials. We demonstrate that Acanthamoeba spp. are resistant to five antimicrotubule compounds, unlike any other eukaryote studied so far. Resistance correlates with critical amino acid differences within the inhibitor binding sites of the tubulin heterodimers

Toxoplasma gondii: Histopathological, Biochemical and Pharmacological Aspects

Toxoplasma gondii, a protozoan parasite, can cause severe, life-threatening disease, especially in newborns and immunosuppressed patients. It is an important cause of ocular disease and is considered to be the most common recognisable cause of posterior uveitis in immunocompetent individuals. The clinical and pathological manifestations of congenital toxoplasmosis in infants, children and adults are well characterised. However, until now, this disease has not been extensively studied in fetuses and there remain certain gaps in our understanding of the earliest stages of congenital disease. The first section of this thesis describes the early pathological changes in the eyes of fetuses and infants. The second section provides evidence for two novel biochemical pathways in T. gondii. These pathways are more commonly associated with plants and algae and may provide new targets for antimicrobial agents. This study of fetal and infant eyes represents the biggest most comprehensive study of its kind to date. Eyes from 10 fetuses and 2 infants with congenital toxoplasmosis were studied by light microscopy. In addition, immunohistochemistry was performed for infiltrating inflammatory cells and T. gondii antigens. The characteristic findings were of retinitis, retinal necrosis, disruption of the retinal pigment epithelium and choroidal inflammation and congestion. Optic neuritis was present in 5 fetal eyes. The eye obtained from a 32 week old fetus showed a well established retinochoroidal scar. At the edge of the scar the retinal architecture was disrupted with formation of rosettes. This was interpreted as focal retinal dysplasia. Mechanisms leading to abnormal retinal development is discussed. T cells, in particular CD4+ T cells, predominated within the retinal lesions and choroid. This demonstrates that the fetus is capable of mounting an immune response to T. gondii. However, this immune response may be less effective than in the child or adult. T gondii organisms were identified in 5 fetuses and two infants by immunohistochemical staining. In one infant eye and one fetal eye parasites were identified in a perivascular location supporting a haematogenous route of dissemination to the eye. These findings demonstrate that ocular toxoplasmosis causes severe irreversible damage to the retina in utero. The significance of these findings to current strategies for prenatal diagnosis and management is discussed. Current treatments are only effective against the rapidly dividing tachyzoite form associated with active disease. There are no treatments capable of eliminating the quiescent cystic bradyzoite stage. This is the source of disease reactivation in the congenitally infected and immunocompromised host. A combination of pyrimethamine and sulphadiazine, both anti-folate agents, is the most effective therapy for active disease currently available. However, there are significant side effects associated with both these drugs. For these reasons, new antimicrobial agents are urgently needed for the treatment of this disease. In recent years there has been considerable interest in the vestigial plastid organelle of T. gondii and Apicomplexans (the subphylum of parasites which include Plasmodium, Theileria, Babesia, Eimeria, Hepatozoon, Sarcocystis and T.gondii) in general. In addition certain other plant-like characteristics have been reported in Apicomplexans. These observations may provide exploitable differences between these parasites and their mammalian hosts. In the second part of this thesis, the possibility that T.gondii may depend on biochemical processes more normally restricted to plants is investigated. The shikimate pathway occurs within the plastid of plants and algae. It is a seven step reaction which catalyses the conversion of phosphoenol pyruvate to chorismate. Chorismate is then used for the synthesis of virtually all aromatic compounds, notably, p-aminobenzoic acid which is required for de novo folic acid synthesis; ubiquinone an essential component of the mitochondrial electron transport chain; and the aromatic amino acids. The studies described in this section of the thesis provide chemotherapeutic and genetic evidence for the shikimate pathway in T. gondii. Firstly, the in vitro growth of T. gondii was inhibited by the herbicide glyphosate, also known as N-(phosphonomethyl)glycine (NPMG), a well characterised inhibitor of the shikimate pathway enzyme 5-enolpyruvyl shikimate 3-phosphate (EPSP) synthase. Furthermore, the effect of NPMG on T.gondii was reversed by treatment with p-aminobenzoic acid, which suggests that the shikimate pathway supplies folate precursors for their growth