1,104 research outputs found
Artemether resistance in vitro is linked to mutations in PfATP6 that also interact with mutations in PfMDR1 in travellers returning with Plasmodium falciparum infections.
BACKGROUND: Monitoring resistance phenotypes for Plasmodium falciparum, using in vitro growth assays, and relating findings to parasite genotype has proved particularly challenging for the study of resistance to artemisinins.
METHODS: Plasmodium falciparum isolates cultured from 28 returning travellers diagnosed with malaria were assessed for sensitivity to artemisinin, artemether, dihydroartemisinin and artesunate and findings related to mutations in pfatp6 and pfmdr1.
RESULTS: Resistance to artemether in vitro was significantly associated with a pfatp6 haplotype encoding two amino acid substitutions (pfatp6 A623E and S769N; (mean IC50 (95% CI) values of 8.2 (5.7 - 10.7) for A623/S769 versus 623E/769 N 13.5 (9.8 - 17.3) nM with a mean increase of 65%; p = 0.012). Increased copy number of pfmdr1 was not itself associated with increased IC50 values for artemether, but when interactions between the pfatp6 haplotype and increased copy number of pfmdr1 were examined together, a highly significant association was noted with IC50 values for artemether (mean IC50 (95% CI) values of 8.7 (5.9 - 11.6) versus 16.3 (10.7 - 21.8) nM with a mean increase of 87%; p = 0.0068). Previously described SNPs in pfmdr1 are also associated with differences in sensitivity to some artemisinins.
CONCLUSIONS: These findings were further explored in molecular modelling experiments that suggest mutations in pfatp6 are unlikely to affect differential binding of artemisinins at their proposed site, whereas there may be differences in such binding associated with mutations in pfmdr1. Implications for a hypothesis that artemisinin resistance may be exacerbated by interactions between PfATP6 and PfMDR1 and for epidemiological studies to monitor emerging resistance are discussed
Realistic constraints on the doubly charged bilepton couplings from Bhabha scattering with LEP data
Upper limits on doubly charged bilepton couplings and masses are extracted
from LEP data for Bhabha scattering at energy range GeV
using standard model program ZFITTER which calculates radiative corrections. We
find that at 95% C.L. for scalar and
vector bileptons.Comment: 5 pages, 1 EPS figur
A Longitudinal Study Of Post-traumatic Growth And Psychological Distress In Colorectal Cancer Survivors
The stability of post-traumatic growth overtime and the relationship between post-traumatic growth and traditional distress outcomes remains unclear. We tracked post-traumatic growth in a population-based sample of colorectal cancer patients from soon after diagnosis to five years subsequently to assess the heterogeneity of a post-traumatic growth response to cancer over time and describe the simultaneous and longitudinal relationships between post-traumatic growth and psychological distress. 1966 colorectal patients who were five months post diagnosis were assessed six times over a five year period. There was considerable heterogeneity associated with both psychological distress and benefit finding scores over time. However, both for benefit finding and psychological distress, the variation in individual scores suggested an underlying positive linear trend and both lagged and lagged change components. Specifically, benefit finding and psychological distress are mutual leading indicators of each other. First, benefit finding served as a leading indicator of distress, in that increases in reported benefit finding from year to year predicted higher future increases in psychological distress. As well, in an inverse relationship, psychological distress served as a leading indicator of benefit finding, such that increases in reported distress from year to year predicted lower future increases in benefit finding. Post-traumatic growth may reflect patients coping efforts to enhance perceptions of wellbeing in response to escalating cancer-related threats, acting as harbinger of increasing trajectories of psychological distress. This explanation is consistent with a cognitive dissonance response in which threats to the integrity of the self then lead to a tendency to accentuate positive aspects of the self
Microcanonical Treatment of Hadronizing the Quark-Gluon Plasma
We recently introduced a completely new way to study ultrarelativistic
nuclear scattering by providing a link between the string model approach and a
statistical description. A key issue is the microcanonical treatment of
hadronizing individual quark matter droplets. In this paper we describe in
detail the hadronization of these droplets according to n-body phase space, by
using methods of statistical physics, i.e. constructing Markov chains of hadron
configurations.Comment: Complete paper enclosed as postscript file (uuencoded
The effects of the spontaneous presence of a spouse/partner and others on cardiovascular reactions to an acute psychological challenge
The presence of supportive others has been associated with attenuated cardiovascular reactivity in the laboratory. The effects of the presence of a spouse and others in a more naturalistic setting have received little attention. Blood pressure and heart rate reactions to mental stress were recorded at home in 1028 married/partnered individuals. For 112 participants, their spouse/partner was present; for 78, at least one other person was present. Women tested with a spouse/partner present showed lower magnitude systolic blood pressure and heart rate reactivity than those tested without. Individuals tested with at least one nonspousal other present also displayed attenuated reactivity. This extends the results of laboratory studies and indicates that the spontaneous presence of others is associated with a reduction in cardiovascular reactivity in an everyday environment; spouse/partner presence would appear to be especially effective for women.\ud
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Toward Common Data Elements for International Research in Long-term Care Homes: Advancing Person-Centered Care
To support person-centered, residential long-term care internationally, a consortium of researchers in medicine, nursing, behavioral, and social sciences from 21 geographically and economically diverse countries have launched the WE-THRIVE consortium to develop a common data infrastructure. WE-THRIVE aims to identify measurement domains that are internationally relevant, including in low-, middle-, and high-income countries, prioritize concepts to operationalize domains, and specify a set of data elements to measure concepts that can be used across studies for data sharing and comparisons. This article reports findings from consortium meetings at the 2016 meeting of the Gerontological Society of America and the 2017 meeting of the International Association of Gerontology and Geriatrics, to identify domains and prioritize concepts, following best practices to identify common data elements (CDEs) that were developed through the US National Institutes of Health/National Institute of Nursing Research's CDEs initiative. Four domains were identified, including organizational context, workforce and staffing, person-centered care, and care outcomes. Using a nominal group process, WE-THRIVE prioritized 21 concepts across the 4 domains. Several concepts showed similarity to existing measurement structures, whereas others differed. Conceptual similarity (convergence; eg, concepts in the care outcomes domain of functional level and harm-free care) provides further support of the critical foundational work in LTC measurement endorsed and implemented by regulatory bodies. Different concepts (divergence; eg, concepts in the person-centered care domain of knowing the person and what matters most to the person) highlights current gaps in measurement efforts and is consistent with WE-THRIVE's focus on supporting resilience and thriving for residents, family, and staff. In alignment with the World Health Organization's call for comparative measurement work for health systems change, WE-THRIVE's work to date highlights the benefits of engaging with diverse LTC researchers, including those in low-, middle-, and high-income countries, to develop a measurement infrastructure that integrates the aspirations of person-centered LTC
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Person-centered nursing home care in the United States, United Kingdom, and Sweden: Why building cross-comparative capacity may help us radically rethink nursing home care and the role of the RN
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