266 research outputs found

    A One Health approach to antimicrobial resistance surveillance: is there a business case for it?

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    Antimicrobial resistance is a global problem of complex epidemiology, suited to a broad, integrated One Health approach. Resistant organisms exist in humans, animals, food and the environment, and the main driver of this resistance is antimicrobial usage. A One Health conceptual framework for surveillance is presented to include all of these aspects. Global and European (regional and national) surveillance systems are described, highlighting shortcomings compared with the framework. Policy decisions rely on economic and scientific evidence, so the business case for a fully integrated system is presented. The costs of integrated surveillance are offset by the costs of unchecked resistance and the benefits arising from interventions and outcomes. Current estimates focus on costs and benefits of human health outcomes. A One Health assessment includes wider societal costs of lost labour, changes in health-seeking behaviour, impacts on animal health and welfare, higher costs of animal-origin food production, and reduced consumer confidence in safety and international trade of such food. Benefits of surveillance may take years to realise and are dependent on effective and accepted interventions. Benefits, including the less tangible, such as improved synergies and efficiencies in service delivery and more timely and accurate risk identification, should also be recognised. By including these less tangible benefits to society, animal welfare, ecosystem health and resilience, together with the savings and efficiencies through shared resources and social capital-building, a stronger business case for a One Health approach to surveillance can be made

    An appraisal of the indigenous chicken market in Tanzania and Zambia. Are the markets ready for improved outputs from village production systems?

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    Traditional or village poultry, consisting primarily of indigenous chickens, make up over 80% of poultry in Africa. Most are kept as small flocks in free-ranging, scavenging, low input production systems. They provide vital nutritional and financial needs especially for children, women of reproductive age, people with HIV/AIDS and the poor. Poultry meat and eggs provide animal source protein and essential micronutrients which improves growth and cognitive development in children. While productivity of indigenous chickens is low due to uncontrolled disease and an unreliable scavenging resource base, the minimal inputs result in a high benefit-cost ratio. By increasing supplementary feeding through improved crop yields and improving disease control through vaccination, a higher number of chickens of greater bodyweight will be available to market. An appraisal of the indigenous chicken market in Tanzania and Zambia was conducted to identify the key individuals (including gender imbalances), market channels, commercialisation margins, market trends and competition from exotic, commercial chickens (broilers and spent layers). Consumers preferred indigenous chickens and urban consumers paid their significantly higher price, which resulted from the accumulative costs of intermediary traders’ fees, transport costs and market fees. Commercial chickens in urban markets sold at a lower price but were vulnerable to fluctuating costs of high inputs. Indigenous chicken producers’ margins were favourable enough to suggest that some additional costs were sustainable, provided the off take channels and consumer confidence is sustained. Markets for indigenous chickens were informal and consequently, their response to increased production may be unpredictable

    A systems analysis and conceptual system dynamics model of the livestock-derived food system in South Africa : a tool for policy guidance

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    Global food production systems are currently under scrutiny, in particular the health, nutrition, and environmental impacts of livestock-derived food (LDF). Despite South Africa’s recent socio­economic transformation and increased per-capita LDF consumption, the triple burden of malnutri­tion persists. Policy responses to such complex problems often fail because of linear thinking with short-term goals. However, a systems approach helps identify root causes, feedback mechanisms, potential unintended consequences, and opportu­nities for integrated, durable solutions. Participa­tion in the systems-thinking process improves stakeholder understanding and buy-in. Our par­ticipatory workshop facilitated the development of a systems map for South African LDF, identifying key system elements, linkages, and nexus points. The latter included climate change, land access and management, livestock management and produc­tivity, farming systems, food safety, policy articula­tion, agricultural knowledge, and income. Based on these findings, and an overview of related litera­ture, we produced a conceptual system dynamics model of the LDF system. We identified key vari­ables and causal relationships, vicious and virtuous loops, system archetypes, conceptual stock and flows, and links to Sustainable Development Goals. The LDF system is complex and dynamic, with a dominance of commercial enterprises across agriculture and food retail, presenting barriers for small and medium-scale individuals. Other key elements relate to population growth and urbaniza­tion, land access, deregulation of international trade, climate change vulnerability, feed production limitations, and food safety. Our work provides a unique reference for policymakers, identifying the need for deep structural change, highlighting the possible unintended consequences, and thereby mitigating the risk of system destabilization

    A national surveillance project on chronic kidney disease management in Canadian primary care: a study protocol.

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    INTRODUCTION: Effective chronic disease care is dependent on well-organised quality improvement (QI) strategies that monitor processes of care and outcomes for optimal care delivery. Although healthcare is provincially/territorially structured in Canada, there are national networks such as the Canadian Primary Care Sentinel Surveillance Network (CPCSSN) as important facilitators for national QI-based studies to improve chronic disease care. The goal of our study is to improve the understanding of how patients with chronic kidney disease (CKD) are managed in primary care and the variation across practices and provinces and territories to drive improvements in care delivery. METHODS AND ANALYSIS: The CPCSSN database contains anonymised health information from the electronic medical records for patients of participating primary care practices (PCPs) across Canada (n=1200). The dataset includes information on patient sociodemographics, medications, laboratory results and comorbidities. Leveraging validated algorithms, case definitions and guidelines will help define CKD and the related processes of care, and these enable us to: (1) determine prevalent CKD burden; (2) ascertain the current practice pattern on risk identification and management of CKD and (3) study variation in care indicators (eg, achievement of blood pressure and proteinuria targets) and referral pattern for specialist kidney care. The process of care outcomes will be stratified across patients' demographics as well as provider and regional (provincial/territorial) characteristics. The prevalence of CKD stages 3-5 will be presented as age-sex standardised prevalence estimates stratified by province and as weighted averages for population rates with 95% CIs using census data. For each PCP, age-sex standardised prevalence will be calculated and compared with expected standardised prevalence estimates. The process-based outcomes will be defined using established methods. ETHICS AND DISSEMINATION: The CPCSSN is committed to high ethical standards when dealing with individual data collected, and this work is reviewed and approved by the Network Scientific Committee. The results will be published in peer-reviewed journals and presented at relevant national and international scientific meetings

    Exploring local knowledge and perceptions on zoonoses among pastoralists in northern and eastern Tanzania

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    Background: Zoonoses account for the most commonly reported emerging and re-emerging infectious diseases in Sub-Saharan Africa. However, there is limited knowledge on how pastoral communities perceive zoonoses in relation to their livelihoods, culture and their wider ecology. This study was carried out to explore local knowledge and perceptions on zoonoses among pastoralists in Tanzania. Methodology and principal findings: This study involved pastoralists in Ngorongoro district in northern Tanzania and Kibaha and Bagamoyo districts in eastern Tanzania. Qualitative methods of focus group discussions, participatory epidemiology and interviews were used. A total of 223 people were involved in the study. Among the pastoralists, there was no specific term in their local language that describes zoonosis. Pastoralists from northern Tanzania possessed a higher understanding on the existence of a number of zoonoses than their eastern districts' counterparts. Understanding of zoonoses could be categorized into two broad groups: a local syndromic framework, whereby specific symptoms of a particular illness in humans concurred with symptoms in animals, and the biomedical framework, where a case definition is supported by diagnostic tests. Some pastoralists understand the possibility of some infections that could cross over to humans from animals but harm from these are generally tolerated and are not considered as threats. A number of social and cultural practices aimed at maintaining specific cultural functions including social cohesion and rites of passage involve animal products, which present zoonotic risk. Conclusions: These findings show how zoonoses are locally understood, and how epidemiology and biomedicine are shaping pastoralists perceptions to zoonoses. Evidence is needed to understand better the true burden and impact of zoonoses in these communities. More studies are needed that seek to clarify the common understanding of zoonoses that could be used to guide effective and locally relevant interventions. Such studies should consider in their approaches the pastoralists' wider social, cultural and economic set up

    Bistability coordinates activation of the EGFR and DPP pathways in Drosophila vein differentiation

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    Cell differentiation in developing tissues is controlled by a small set of signaling pathways, which must coordinate the timing and levels of activation to ensure robust and precise outcomes. Highly coordinated activation of signaling pathways can result from cross-regulatory interactions in multi-pathway networks. Here we explore the dynamics and function of pathway coordination between the EGFR and DPP pathways during Drosophila wing-vein differentiation. We show that simultaneous activation of both the EGFR and DPP pathways must be maintained for vein cell differentiation and that above-threshold ectopic activation of either pathway is sufficient to drive vein cell differentiation outside the proveins. The joint activation of the EGFR and DPP signaling systems is ensured by a positive feedback loop, in which the two pathways stimulate each other at the level of ligand production

    Voluntary exercise can strengthen the circadian system in aged mice

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    Consistent daily rhythms are important to healthy aging according to studies linking disrupted circadian rhythms with negative health impacts. We studied the effects of age and exercise on baseline circadian rhythms and on the circadian system's ability to respond to the perturbation induced by an 8 h advance of the light:dark (LD) cycle as a test of the system's robustness. Mice (male, mPer2luc/C57BL/6) were studied at one of two ages: 3.5 months (n = 39) and >18 months (n = 72). We examined activity records of these mice under entrained and shifted conditions as well as mPER2::LUC measures ex vivo to assess circadian function in the suprachiasmatic nuclei (SCN) and important target organs. Age was associated with reduced running wheel use, fragmentation of activity, and slowed resetting in both behavioral and molecular measures. Furthermore, we observed that for aged mice, the presence of a running wheel altered the amplitude of the spontaneous firing rate rhythm in the SCN in vitro. Following a shift of the LD cycle, both young and aged mice showed a change in rhythmicity properties of the mPER2::LUC oscillation of the SCN in vitro, and aged mice exhibited longer lasting internal desynchrony. Access to a running wheel alleviated some age-related changes in the circadian system. In an additional experiment, we replicated the effect of the running wheel, comparing behavioral and in vitro results from aged mice housed with or without a running wheel (>21 months, n = 8 per group, all examined 4 days after the shift). The impact of voluntary exercise on circadian rhythm properties in an aged animal is a novel finding and has implications for the health of older people living with environmentally induced circadian disruption

    D-Cbl Binding to Drk Leads to Dose-Dependent Down-Regulation of EGFR Signaling and Increases Receptor-Ligand Endocytosis

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    Proper control of Epidermal Growth Factor Receptor (EGFR) signaling is critical for normal development and regulated cell behaviors. Abnormal EGFR signaling is associated with tumorigenic process of various cancers. Complicated feedback networks control EGFR signaling through ligand production, and internalization-mediated destruction of ligand-receptor complexes. Previously, we found that two isoforms of D-Cbl, D-CblS and D-CblL, regulate EGFR signaling through distinct mechanisms. While D-CblL plays a crucial role in dose-dependent down-regulation of EGFR signaling, D-CblS acts in normal restriction of EGFR signaling and does not display dosage effect. Here, we determined the underlying molecular mechanism, and found that Drk facilitates the dose-dependent regulation of EGFR signaling through binding to the proline-rich motif of D-CblL, PR. Furthermore, the RING finger domain of D-CblL is essential for promoting endocytosis of the ligand-receptor complex. Interestingly, a fusion protein of the two essential domains of D-CblL, RING- PR, is sufficient to down-regulate EGFR signal in a dose-dependent manner by promoting internalization of the ligand, Gurken. Besides, RING-SH2Drk, a fusion protein of the RING finger domain of D-Cbl and the SH2 domain of Drk, also effectively down-regulates EGFR signaling in Drosophila follicle cells, and suppresses the effects of constitutively activated EGFR. The RING-SH2Drk suppresses EGFR signaling by promoting the endosomal trafficking of ligand-receptor complexes, suggesting that Drk plays a negative role in EGFR signaling by enhancing receptor endocytosis through cooperating with the RING domain of D-Cbl. Interfering the recruitment of signal transducer, Drk, to the receptor by the RING-SH2Drk might further reduces EGFR signaling. The fusion proteins we developed may provide alternative strategies for therapy of cancers caused by hyper-activation of EGFR signaling

    Localization of the Drosophila Rad9 Protein to the Nuclear Membrane Is Regulated by the C-Terminal Region and Is Affected in the Meiotic Checkpoint

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    Rad9, Rad1, and Hus1 (9-1-1) are part of the DNA integrity checkpoint control system. It was shown previously that the C-terminal end of the human Rad9 protein, which contains a nuclear localization sequence (NLS) nearby, is critical for the nuclear transport of Rad1 and Hus1. In this study, we show that in Drosophila, Hus1 is found in the cytoplasm, Rad1 is found throughout the entire cell and that Rad9 (DmRad9) is a nuclear protein. More specifically, DmRad9 exists in two alternatively spliced forms, DmRad9A and DmRad9B, where DmRad9B is localized at the cell nucleus, and DmRad9A is found on the nuclear membrane both in Drosophila tissues and also when expressed in mammalian cells. Whereas both alternatively spliced forms of DmRad9 contain a common NLS near the C terminus, the 32 C-terminal residues of DmRad9A, specific to this alternative splice form, are required for targeting the protein to the nuclear membrane. We further show that activation of a meiotic checkpoint by a DNA repair gene defect but not defects in the anchoring of meiotic chromosomes to the oocyte nuclear envelope upon ectopic expression of non-phosphorylatable Barrier to Autointegration Factor (BAF) dramatically affects DmRad9A localization. Thus, by studying the localization pattern of DmRad9, our study reveals that the DmRad9A C-terminal region targets the protein to the nuclear membrane, where it might play a role in response to the activation of the meiotic checkpoint
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