206 research outputs found
Effect of Mass Supplementation with Ready-to-Use Supplementary Food during an anticipated nutritional emergency
Previous studies have shown the benefits of ready-to-use supplementary food (RUSF) distribution in reducing the incidence and prevalence of severe acute malnutrition
Parliamentary co-evolution: national parliamentary reactions to the empowerment of the European Parliament
Existing research on the European Union's (EU) multilevel parliamentary system builds on the hypothesis of parallel evolution, situating explanations for European Parliament (EP) empowerment at the EU level and explanations for national parliamentary powers in EU affairs at the national level. We propose the hypothesis of co-evolution, which specifies a connection between national and European arenas of parliamentarization. We study whether the EP's empowerment enhances or reduces pressure on national parliaments to strengthen their own EU-related competences. First, we argue that national parliamentary parties take conscious positions on the powers of the EP. Second, support for the EP among the party composition of national parliaments tells us whether parliaments regard the EP as a competitor or ally, feeling pressed, or relieved of the pressure, to strengthen their EU-related competences
Immune phenotypes that are associated with subsequent COVID-19 severity inferred from post-recovery samples
Severe COVID-19 causes profound immune perturbations, but pre-infection immune signatures contributing to severe COVID-19 remain unknown. Genome-wide association studies (GWAS) identified strong associations between severe disease and several chemokine receptors and molecules from the type I interferon pathway. Here, we define immune signatures associated with severe COVID-19 using high-dimensional flow cytometry. We measure the cells of the peripheral immune system from individuals who recovered from mild, moderate, severe or critical COVID-19 and focused only on those immune signatures returning to steady-state. Individuals that suffered from severe COVID-19 show reduced frequencies of T cell, mucosal-associated invariant T cell (MAIT) and dendritic cell (DC) subsets and altered chemokine receptor expression on several subsets, such as reduced levels of CCR1 and CCR2 on monocyte subsets. Furthermore, we find reduced frequencies of type I interferon-producing plasmacytoid DCs and altered IFNAR2 expression on several myeloid cells in individuals recovered from severe COVID-19. Thus, these data identify potential immune mechanisms contributing to severe COVID-19
Superior T memory stem cell persistence supports long-lived T cell memory
Long-lived memory T cells are able to persist in the host in the absence of antigen; however, the mechanism by which they are maintained is not well understood. Recently, a subset of human T cells, stem cell memory T cells (TSCM cells), was shown to be self-renewing and multipotent, thereby providing a potential reservoir for T cell memory throughout life. However, their in vivo dynamics and homeostasis still remain to be defined due to the lack of suitable animal models. We identified T cells with a TSCM phenotype and stem cell–like properties in nonhuman primates. These cells were the least-differentiated memory subset, were functionally distinct from conventional memory cells, and served as precursors of central memory. Antigen-specific TSCM cells preferentially localized to LNs and were virtually absent from mucosal surfaces. They were generated in the acute phase of viral infection, preferentially survived in comparison with all other memory cells following elimination of antigen, and stably persisted for the long term. Thus, one mechanism for maintenance of long-term T cell memory derives from the unique homeostatic properties of TSCM cells. Vaccination strategies designed to elicit durable cellular immunity should target the generation of TSCM cells
Evaluation of psychological support for victims of sexual violence in a conflict setting: results from Brazzaville, Congo
ABSTRACT: BACKGROUND: Little is known about the impact of psychological support in war and transcultural contexts and in particular, whether there are lasting benefits. Here, we present an evaluation of the late effect of post-rape psychological support provided to women in Brazzaville, Republic of Congo. METHODS: Women who attended the Médecins Sans Frontières program for sexual violence in Brazzaville during the conflict were selected to evaluate the psychological consequences of rape and the late effect of post-rape psychological support. A total of 178 patients met the eligibility criteria: 1) Women aged more than 15 years; 2) raped by unknown person(s) wearing military clothes; 3) admitted to the program between the 1/1/2002 and the 30/4/2003; and 4) living in Brazzaville. RESULTS: The initial diagnosis according to DSM criteria showed a predominance of anxious disorders (54.1%) and acute stress disorders (24.6%). One to two years after the initial psychological care, 64 women were evaluated using the Trauma Screening Questionnaire (TSQ), the Global Assessment of Functioning scale (GAF) and an assessment scale to address medico-psychological care in emergencies (EUMP). Two patients (3.1%) met the needed criteria for PTSD diagnosis from the TSQ. Among the 56 women evaluated using GAF both as pre and post-test, global functioning was significantly improved by initial post-rape support (50 women (89.3%) had extreme or medium impairment at first post-rape evaluation, and 16 (28.6%) after psychological care; p = 0.04). When interviewed one to two years later, the benefit was fully maintained (16 women (28.6%) presenting extreme or medium impairment). CONCLUSION: We found the benefits of post-rape psychological support to be present and lasting in this conflict situation. However, we were unable to evaluate all women for the long-term impact, underscoring the difficulty of leading evaluation studies in unstable contexts. Future research is needed to validate these findings in other settings
Preventive Effects of Long-Term Supplementation with 2 Nutritious Food Supplements in Young Children in Niger
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Lithium abundances in CEMP stars
Carbon-enhanced metal-poor (CEMP) stars are believed to show the chemical
imprints of more massive stars (M > 0.8 Msun) that are now extinct. In
particular, it is expected that the observed abundance of Li should deviate in
these stars from the standard Spite lithium plateau. We study here a sample of
11 metal-poor stars and a double-lined spectroscopic binary with -1.8 <[Fe/H]<
-3.3 observed with VLT/UVES spectrograph. Among these 12 metal-poor stars,
there are 8 CEMP stars for which we measure or constrain the Li abundance. In
contrast to previous arguments, we demonstrate that an appropriate regime of
dilution permits the existence of "Li-Spite plateau and C-rich" stars, whereas
some of the "Li-depleted and C-rich" stars call for an unidentified additional
depletion mechanism that cannot be explained by dilution alone. We find
evidence that rotation is related to the Li depletion in some CEMP stars.
Additionally, we report on a newly recognized double-lined spectroscopic binary
star in our sample. For this star, we develop a new technique from which
estimates of stellar parameters and luminosity ratios can be derived based on a
high-resolution spectrum alone, without the need for input from evolutionary
models.Comment: 62 pages, 16 figures, accepted for publication in Ap
Performance of Small Cluster Surveys and the Clustered LQAS Design to estimate Local-level Vaccination Coverage in Mali
<p>Abstract</p> <p>Background</p> <p>Estimation of vaccination coverage at the local level is essential to identify communities that may require additional support. Cluster surveys can be used in resource-poor settings, when population figures are inaccurate. To be feasible, cluster samples need to be small, without losing robustness of results. The clustered LQAS (CLQAS) approach has been proposed as an alternative, as smaller sample sizes are required.</p> <p>Methods</p> <p>We explored (i) the efficiency of cluster surveys of decreasing sample size through bootstrapping analysis and (ii) the performance of CLQAS under three alternative sampling plans to classify local VC, using data from a survey carried out in Mali after mass vaccination against meningococcal meningitis group A.</p> <p>Results</p> <p>VC estimates provided by a 10 × 15 cluster survey design were reasonably robust. We used them to classify health areas in three categories and guide mop-up activities: i) health areas not requiring supplemental activities; ii) health areas requiring additional vaccination; iii) health areas requiring further evaluation. As sample size decreased (from 10 × 15 to 10 × 3), standard error of VC and ICC estimates were increasingly unstable. Results of CLQAS simulations were not accurate for most health areas, with an overall risk of misclassification greater than 0.25 in one health area out of three. It was greater than 0.50 in one health area out of two under two of the three sampling plans.</p> <p>Conclusions</p> <p>Small sample cluster surveys (10 × 15) are acceptably robust for classification of VC at local level. We do not recommend the CLQAS method as currently formulated for evaluating vaccination programmes.</p
A density-temperature description of the outer electron radiation belt during geomagnetic storms
Bi-Maxwellian fits are made to energetic-electron flux measurements from seven satellites in geosynchronous orbit, yielding a number density (n) and temperature (T) description of the outer electron radiation belt. For 54.5 spacecraft years of measurements the median value of n is 3.7 × 10−4 cm−3, and the median value of T is 148 keV. General statistical properties of n, T, and the 1.1–1.5 MeV flux F are investigated, including local-time and solar-cycle dependencies. Using superposed-epoch analysis where the zero epoch is convection onset, the evolution of the outer electron radiation belt through high-speed-stream-driven storms is investigated. The number-density decay during the calm before the storm, relativistic-electron dropouts and recoveries, and the heating of the outer electron radiation belt during storms are analyzed. Using four different “triggers” (sudden storm commencement (SSC), southward interplanetary magnetic field (IMF) portions of coronal mass ejection (CME) sheaths, southward-IMF portions of magnetic clouds, and minimum Dst) a selection of CME-driven storms are analyzed with superposed-epoch techniques. For CME-driven storms, only a very modest density decay prior to storm onset is found. In addition, the compression of the outer electron radiation belt at the time of SSC is analyzed, the number-density increase and temperature decrease during storm main phase are characterized, and the increase in density and temperature during storm recovery phase is determined. During the different phases of storms, changes in the flux are sometimes in response to changes in the temperature, sometimes to changes in the number density, and sometimes to changes in both. Differences are found between the density-temperature and flux descriptions, and it is concluded that more information is available using the density-temperature description
T Cells Specific for a Mycobacterial Glycolipid Expand after Intravenous Bacillus Calmette-Guérin Vaccination
Intradermal vaccination with Mycobacterium bovis bacillus Calmette-Guérin (BCG) protects infants from disseminated tuberculosis, and i.v. BCG protects nonhuman primates (NHP) against pulmonary and extrapulmonary tuberculosis. In humans and NHP, protection is thought to be mediated by T cells, which typically recognize bacterial peptide Ags bound to MHC proteins. However, during vertebrate evolution, T cells acquired the capacity to recognize lipid Ags bound to CD1a, CD1b, and CD1c proteins expressed on APCs. It is unknown whether BCG induces T cell immunity to mycobacterial lipids and whether CD1-restricted T cells are resident in the lung. In this study, we developed and validated Macaca mulatta (Mamu) CD1b and CD1c tetramers to probe ex vivo phenotypes and functions of T cells specific for glucose monomycolate (GMM), an immunodominant mycobacterial lipid Ag. We discovered that CD1b and CD1c present GMM to T cells in both humans and NHP. We show that GMM-specific T cells are expanded in rhesus macaque blood 4 wk after i.v. BCG, which has been shown to protect NHP with near-sterilizing efficacy upon M. tuberculosis challenge. After vaccination, these T cells are detected at high frequency within bronchoalveolar fluid and express CD69 and CD103, markers associated with resident memory T cells. Thus, our data expand the repertoire of T cells known to be induced by whole cell mycobacterial vaccines, such as BCG, and show that lipid Ag-specific T cells are resident in the lungs, where they may contribute to protective immunity
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