650 research outputs found

    Problem-based leadership: nurturing managers during turbulent times

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    Purpose – The paper explores problem-based learning (PBL) as a useful methodology in leadership development during turbulent times. It identifies several pertinent action points for managers to lead through problems while understanding their capacity to empower themselves and others to face challenges at work. Design/methodology/approach – Broad concepts of PBL are used to distil the characteristics of this methodology and how they might be applicable to leadership development. An actual case of PBL in leadership education and training is employed to illustrate the processes of problem solving and reflective action-taking. Findings – When confronted by problems, managers should adopt a learning-oriented mindset and draw on the strengths of others to generate immediate solutions for experimentation. In doing so, they need to accept failure as a prerequisite for creative tensions to be generated and applied in messy circumstances. Until they think out of the box, they will continue to solve problems in tried-and-tested ways obstructing the emergence of revolutionary solutions. Practical implications – In order for managers to make an impact on organizational process and improvement, they need to focus on the action and learn components of PBL. They should be given the space to listen to their own “voice” and internalize the “voice” of others through reflection and dialogue. They should also be recognized for their courage and boldness in confronting problems even if more problems are generated in the process. It is facing the goliath that managers truly grow to become real leaders. Originality/value – Although the concept of PBL has been around for a long while, its applicability to leadership development has not been sufficiently explored in both theory and practice. This paper brings another dimension to the common idea of problem solving where solution seeking is not an end it itself. At best, it is a means to discovering the potential of true leadership in those whose mindset is focused on learning and reflective decision-making

    Getting Lost to be Found: The Insider-Outsider Paradoxes in Relational Ethnography

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    Purpose: The paper draws on the direct experience of a practitioner undertaking real-time research in his organization to offer insights into the dual role of practical insider and theoretical outsider. The duality helps the researcher to live ‘in’ and think ‘out’ of the research context to develop a theory for practice and then transpose it to a practice for theory through the collaboration of an external theoretical insider. Design/Methodology/Approach: This is a theoretical account of the reflexive experience of the practitioner reintroducing relational ethnography, where the researcher regards processes and spaces as the objects of analysis rather than bounded groups and places. It emphasizes the relational significance of the researcher, researched, and theoretical insider in exploring the structures of relations and meanings in the field of professional practice. Findings: The paper argues that understanding the complementariness and paradoxes of the dual role helps the researcher to identify knowledge gaps and contest commonsense knowledge in search of critical knowledge and theoretical insights. Transition between the bounded (restrained) and unbounded (unrestrained) selves occurs in the holding space of research, influencing the position from which the researcher views himself, his subjects, and his social world. Originality/Value: The paper extends the dimension of ethnographic research, which de-centers the authority and control of the researcher to that of the relationship between the researcher and informants, by focusing on the relational significance between the researcher, researched, and theoretical insider. This perspective gives rise to a deeper understanding of relational ethnography, seen largely in sociological research, as relevant to organizational research, where structures of relations and actions explored in real-time could account for the configuration, conflict, and coordination of work practices

    Heme oxygenase-1 deficiency alters erythroblastic Island formation, steady-state erythropoiesis and red blood cell lifespan in mice

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    Heme oxygenase-1 is critical for iron recycling during red blood cell turnover, whereas its impact on steady-state erythropoiesis and red blood cell lifespan is not known. We show here that in 8- to 14-week old mice, heme oxygenase- 1 deficiency adversely affects steady-state erythropoiesis in the bone marrow. This is manifested by a decrease in Ter-119+-erythroid cells, abnormal adhesion molecule expression on macrophages and erythroid cells, and a greatly diminished ability to form erythroblastic islands. Compared with wild-type animals, red blood cell size and hemoglobin content are decreased, while the number of circulating red blood cells is increased in heme oxygenase-1 deficient mice, overall leading to microcytic anemia. Heme oxygenase-1 deficiency increases oxidative stress in circulating red blood cells and greatly decreases the frequency of macrophages expressing the phosphatidylserine receptor Tim4 in bone marrow, spleen and liver. Heme oxygenase-1 deficiency increases spleen weight and Ter119+-erythroid cells in the spleen, although α4β1-integrin expression by these cells and splenic macrophages positive for vascular cell adhesion molecule 1 are both decreased. Red blood cell lifespan is prolonged in heme oxygenase-1 deficient mice compared with wild-type mice. Our findings suggest that while macrophages and relevant receptors required for red blood cell formation and removal are substantially depleted in heme oxygenase- 1 deficient mice, the extent of anemia in these mice may be ameliorated by the prolonged lifespan of their oxidatively stressed erythrocytes

    A Variant PfCRT Isoform Can Contribute to Plasmodium falciparum Resistance to the First-Line Partner Drug Piperaquine

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    Current efforts to reduce the global burden of malaria are threatened by the rapid spread throughout Asia of Plasmodium falciparum resistance to artemisininbased combination therapies, which includes increasing rates of clinical failure with dihydroartemisinin plus piperaquine (PPQ) in Cambodia. Using zinc finger nucleasebased gene editing, we report that addition of the C101F mutation to the chloroquine (CQ) resistance-conferring PfCRT Dd2 isoform common to Asia can confer PPQ resistance to cultured parasites. Resistance was demonstrated as significantly higher PPQ concentrations causing 90% inhibition of parasite growth (IC90) or 50% parasite killing (50% lethal dose [LD50]). This mutation also reversed Dd2-mediated CQ resistance, sensitized parasites to amodiaquine, quinine, and artemisinin, and conferred amantadine and blasticidin resistance. Using heme fractionation assays, we demonstrate that PPQ causes a buildup of reactive free heme and inhibits the formation of chemically inert hemozoin crystals. Our data evoke inhibition of heme detoxification in the parasite’s acidic digestive vacuole as the primary mode of both the bisaminoquinoline PPQ and the related 4-aminoquinoline CQ. Both drugs also inhibit hemoglobin proteolysis at elevated concentrations, suggesting an additional mode of action. Isogenic lines differing in their pfmdr1 copy number showed equivalent PPQ susceptibilities. We propose that mutations in PfCRT could contribute to a multifactorial basis of PPQ resistance in field isolates

    A Variant PfCRT Isoform Can Contribute to Plasmodium falciparum Resistance to the First-Line Partner Drug Piperaquine

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    Current efforts to reduce the global burden of malaria are threatened by the rapid spread throughout Asia of Plasmodium falciparum resistance to artemisinin-based combination therapies, which includes increasing rates of clinical failure with dihydroartemisinin plus piperaquine (PPQ) in Cambodia. Using zinc finger nuclease-based gene editing, we report that addition of the C101F mutation to the chloroquine (CQ) resistance-conferring PfCRT Dd2 isoform common to Asia can confer PPQ resistance to cultured parasites. Resistance was demonstrated as significantly higher PPQ concentrations causing 90% inhibition of parasite growth (IC90) or 50% parasite killing (50% lethal dose [LD50]). This mutation also reversed Dd2-mediated CQ resistance, sensitized parasites to amodiaquine, quinine, and artemisinin, and conferred amantadine and blasticidin resistance. Using heme fractionation assays, we demonstrate that PPQ causes a buildup of reactive free heme and inhibits the formation of chemically inert hemozoin crystals. Our data evoke inhibition of heme detoxification in the parasite’s acidic digestive vacuole as the primary mode of both the bis-aminoquinoline PPQ and the related 4-aminoquinoline CQ. Both drugs also inhibit hemoglobin proteolysis at elevated concentrations, suggesting an additional mode of action. Isogenic lines differing in their pfmdr1 copy number showed equivalent PPQ susceptibilities. We propose that mutations in PfCRT could contribute to a multifactorial basis of PPQ resistance in field isolates

    Study protocol: differential effects of diet and physical activity based interventions in pregnancy on maternal and fetal outcomes--individual patient data (IPD) meta-analysis and health economic evaluation.

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    © 2014 Ruifrok et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.BACKGROUND: Pregnant women who gain excess weight are at risk of complications during pregnancy and in the long term. Interventions based on diet and physical activity minimise gestational weight gain with varied effect on clinical outcomes. The effect of interventions on varied groups of women based on body mass index, age, ethnicity, socioeconomic status, parity, and underlying medical conditions is not clear. Our individual patient data (IPD) meta-analysis of randomised trials will assess the differential effect of diet- and physical activity-based interventions on maternal weight gain and pregnancy outcomes in clinically relevant subgroups of women. METHODS/DESIGN: Randomised trials on diet and physical activity in pregnancy will be identified by searching the following databases: MEDLINE, EMBASE, BIOSIS, LILACS, Pascal, Science Citation Index, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Health Technology Assessment Database. Primary researchers of the identified trials are invited to join the International Weight Management in Pregnancy Collaborative Network and share their individual patient data. We will reanalyse each study separately and confirm the findings with the original authors. Then, for each intervention type and outcome, we will perform as appropriate either a one-step or a two-step IPD meta-analysis to obtain summary estimates of effects and 95% confidence intervals, for all women combined and for each subgroup of interest. The primary outcomes are gestational weight gain and composite adverse maternal and fetal outcomes. The difference in effects between subgroups will be estimated and between-study heterogeneity suitably quantified and explored. The potential for publication bias and availability bias in the IPD obtained will be investigated. We will conduct a model-based economic evaluation to assess the cost effectiveness of the interventions to manage weight gain in pregnancy and undertake a value of information analysis to inform future research. SYSTEMATIC REVIEW REGISTRATION: PROSPERO 2013: CRD42013003804.This study was funded by the National Institute for Health Research (NIHR) HTA (Health Technology Assessment) UK programme 12/01

    Metastatic disease to the pancreas and spleen

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    Isolated metastases to the pancreas and spleen are a rare occurrence. When they are diagnosed, pancreatic metastases are most often from renal cell carcinoma, lung cancer, and breast cancer. The most common source of splenic metastases is gynecological in origin; the overwhelming majority is ovarian. If extensive staging studies reveal these metastases to be isolated, then curative resection may be warranted. This review will demonstrate that long-term survival may be achieved in patients with isolated metastases and a prolonged disease-free interval

    Expansion of the human μ-opioid receptor gene architecture: novel functional variants

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    The μ-opioid receptor (OPRM1) is the principal receptor target for both endogenous and exogenous opioid analgesics. There are substantial individual differences in human responses to painful stimuli and to opiate drugs that are attributed to genetic variations in OPRM1. In searching for new functional variants, we employed comparative genome analysis and obtained evidence for the existence of an expanded human OPRM1 gene locus with new promoters, alternative exons and regulatory elements. Examination of polymorphisms within the human OPRM1 gene locus identified strong association between single nucleotide polymorphism (SNP) rs563649 and individual variations in pain perception. SNP rs563649 is located within a structurally conserved internal ribosome entry site (IRES) in the 5′-UTR of a novel exon 13-containing OPRM1 isoforms (MOR-1K) and affects both mRNA levels and translation efficiency of these variants. Furthermore, rs563649 exhibits very strong linkage disequilibrium throughout the entire OPRM1 gene locus and thus affects the functional contribution of the corresponding haplotype that includes other functional OPRM1 SNPs. Our results provide evidence for an essential role for MOR-1K isoforms in nociceptive signaling and suggest that genetic variations in alternative OPRM1 isoforms may contribute to individual differences in opiate responses

    Preclinical characterization and target validation of the antimalarial pantothenamide MMV693183.

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    Drug resistance and a dire lack of transmission-blocking antimalarials hamper malaria elimination. Here, we present the pantothenamide MMV693183 as a first-in-class acetyl-CoA synthetase (AcAS) inhibitor to enter preclinical development. Our studies demonstrate attractive drug-like properties and in vivo efficacy in a humanized mouse model of Plasmodium falciparum infection. The compound shows single digit nanomolar in vitro activity against P. falciparum and P. vivax clinical isolates, and potently blocks P. falciparum transmission to Anopheles mosquitoes. Genetic and biochemical studies identify AcAS as the target of the MMV693183-derived antimetabolite, CoA-MMV693183. Pharmacokinetic-pharmacodynamic modelling predict that a single 30 mg oral dose is sufficient to cure a malaria infection in humans. Toxicology studies in rats indicate a \u3e 30-fold safety margin in relation to the predicted human efficacious exposure. In conclusion, MMV693183 represents a promising candidate for further (pre)clinical development with a novel mode of action for treatment of malaria and blocking transmission
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