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731.
A common variant in the MTNR1b gene is associated with increased risk of impaired fasting glucose (IFG) in youth with obesity 下载免费PDF全文
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734.
Anne-Gaelle Besnard Rodrigo Guabiraba Wanda Niedbala Jennifer Palomo Flora Reverchon Tovah N. Shaw Kevin N. Couper Bernhard Ryffel Foo Y. Liew 《PLoS pathogens》2015,11(2)
Cerebral malaria (CM) is a complex parasitic disease caused by Plasmodium sp. Failure to establish an appropriate balance between pro- and anti-inflammatory immune responses is believed to contribute to the development of cerebral pathology. Using the blood-stage PbA (Plasmodium berghei ANKA) model of infection, we show here that administration of the pro-Th2 cytokine, IL-33, prevents the development of experimental cerebral malaria (ECM) in C57BL/6 mice and reduces the production of inflammatory mediators IFN-γ, IL-12 and TNF-α. IL-33 drives the expansion of type-2 innate lymphoid cells (ILC2) that produce Type-2 cytokines (IL-4, IL-5 and IL-13), leading to the polarization of the anti-inflammatory M2 macrophages, which in turn expand Foxp3 regulatory T cells (Tregs). PbA-infected mice adoptively transferred with ILC2 have elevated frequency of M2 and Tregs and are protected from ECM. Importantly, IL-33-treated mice deleted of Tregs (DEREG mice) are no longer able to resist ECM. Our data therefore provide evidence that IL-33 can prevent the development of ECM by orchestrating a protective immune response via ILC2, M2 macrophages and Tregs. 相似文献
735.
Background
Previous studies have reported an inverse association between vitamin D and childhood dental caries, but whether this is causal is unclear.Objective
To determine the causal effect of circulating 25-hydroxyvitamin D concentration on dental caries experience, early caries onset and the requirement for a dental general anesthetic.Design
A Mendelian randomization study was undertaken, using genetic variants known to be associated with circulating 25-hydroxyvitamin D concentrations in 5,545 European origin children from the South West of England. Data on caries and related characteristics were obtained from parental and child completed questionnaires between 38 and 91 months and clinical assessments in a random 10% sample at 31, 44 and 61 months.Results
In multivariable confounder adjusted analyses no strong evidence for an association of 25-hydroxyvitamin D with caries experience or severity was found but there was evidence for an association with early caries onset, or having a general anesthetic for dental problems. In Mendelian randomization analysis the odds ratio for caries experience per 10 nmol/L increase in 25-hydroxyvitamin D was 0.93 (95% confidence interval: 0.83, 1.05; P = 0.26) and the odds ratio for dental general anaesthetic per 10 nmol/L increase in 25-hydroxyvitamin D was 0.96 (95% confidence interval: 0.75, 1.22; P = 0.72).Conclusions
This Mendelian randomization study provides little evidence to support an inverse causal effect of 25-hydroxyvitamin D on dental caries. However, the estimates are imprecise and a larger study is required to refine these analyses. 相似文献736.
Claudio Casanova Fernanda E. Colla-Jacques James G. C. Hamilton Reginaldo P. Brazil Jeffrey J. Shaw 《PLoS neglected tropical diseases》2015,9(3)
BackgroundAmerican visceral leishmaniasis (AVL) is an emerging disease in the state of São Paulo, Brazil. Its geographical expansion and the increase in the number of human cases has been linked to dispersion of Lutzomyia longipalpis into urban areas. To produce more accurate risk maps we investigated the geographic distribution and routes of expansion of the disease as well as chemotype populations of the vector.Conclusion/SignificanceThe maps in the present study show that there are two distinct epidemiological patterns of AVL in São Paulo State and that the expansion of human and canine AVL cases through the Western region has followed the same dispersion route of only one of the two species of the L. longipalpis complex, (S)-9-methylgermacrene-B. Entomological vigilance based on the routes of dispersion and identification of the chemotype population could be used to identify at-risk areas and consequently define the priorities for control measures. 相似文献
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Michael P. Lerario Gino Gialdini Daniel M. Lapidus Mesha M. Shaw Babak B. Navi Alexander E. Merkler Gregory Y. H. Lip Jeff S. Healey Hooman Kamel 《PloS one》2015,10(12)
Background
We aimed to estimate the risk of ischemic stroke after intracranial hemorrhage in patients with atrial fibrillation.Materials and Methods
Using discharge data from all nonfederal acute care hospitals and emergency departments in California, Florida, and New York from 2005 to 2012, we identified patients at the time of a first-recorded encounter with a diagnosis of atrial fibrillation. Ischemic stroke and intracranial hemorrhage were identified using validated diagnosis codes. Kaplan-Meier survival statistics and Cox proportional hazard analyses were used to evaluate cumulative rates of ischemic stroke and the relationship between incident intracranial hemorrhage and subsequent stroke.Results
Among 2,084,735 patients with atrial fibrillation, 50,468 (2.4%) developed intracranial hemorrhage and 89,594 (4.3%) developed ischemic stroke during a mean follow-up period of 3.2 years. The 1-year cumulative rate of stroke was 8.1% (95% CI, 7.5–8.7%) after intracerebral hemorrhage, 3.9% (95% CI, 3.5–4.3%) after subdural hemorrhage, and 2.0% (95% CI, 2.0–2.1%) in those without intracranial hemorrhage. After adjustment for the CHA2DS2-VASc score, stroke risk was elevated after both intracerebral hemorrhage (hazard ratio [HR], 2.8; 95% CI, 2.6–2.9) and subdural hemorrhage (HR, 1.6; 95% CI, 1.5–1.7). Cumulative 1-year rates of stroke ranged from 0.9% in those with subdural hemorrhage and a CHA2DS2-VASc score of 0, to 33.3% in those with intracerebral hemorrhage and a CHA2DS2-VASc score of 9.Conclusions
In a large, heterogeneous cohort, patients with atrial fibrillation faced a substantially heightened risk of ischemic stroke after intracranial hemorrhage. The risk was most marked in those with intracerebral hemorrhage and high CHA2DS2-VASc scores. 相似文献738.
739.
Susan J. Bartlett Ana-Maria Orbai Trisha Duncan Elaine DeLeon Victoria Ruffing Katherine Clegg-Smith Clifton O. Bingham III 《PloS one》2015,10(9)
Purpose
To evaluate the reliability and validity of 11 PROMIS measures to assess symptoms and impacts identified as important by people with rheumatoid arthritis (RA).Methods
Consecutive patients (N = 177) in an observational study completed PROMIS computer adapted tests (CATs) and a short form (SF) assessing pain, fatigue, physical function, mood, sleep, and participation. We assessed test-test reliability and internal consistency using correlation and Cronbach’s alpha. We assessed convergent validity by examining Pearson correlations between PROMIS measures and existing measures of similar domains and known groups validity by comparing scores across disease activity levels using ANOVA.Results
Participants were mostly female (82%) and white (83%) with mean (SD) age of 56 (13) years; 24% had ≤ high school, 29% had RA ≤ 5 years with 13% ≤ 2 years, and 22% were disabled. PROMIS Physical Function, Pain Interference and Fatigue instruments correlated moderately to strongly (rho’s ≥ 0.68) with corresponding PROs. Test-retest reliability ranged from .725–.883, and Cronbach’s alpha from .906–.991. A dose-response relationship with disease activity was evident in Physical Function with similar trends in other scales except Anger.Conclusions
These data provide preliminary evidence of reliability and construct validity of PROMIS CATs to assess RA symptoms and impacts, and feasibility of use in clinical care. PROMIS instruments captured the experiences of RA patients across the broad continuum of RA symptoms and function, especially at low disease activity levels. Future research is needed to evaluate performance in relevant subgroups, assess responsiveness and identify clinically meaningful changes. 相似文献740.