242 research outputs found
CXC chemokines and antimicrobial peptides in rhinovirus-induced experimental asthma exacerbations
RATIONALE: Rhinoviruses (RVs) are the major triggers of asthma exacerbations. We have shown previously that lower respiratory tract symptoms, airflow obstruction, and neutrophilic airway inflammation were increased in experimental RV-induced asthma exacerbations. OBJECTIVES: We hypothesized that neutrophil-related CXC chemokines and antimicrobial peptides are increased and related to clinical, virologic, and pathologic outcomes in RV-induced exacerbations of asthma. METHODS: Protein levels of antimicrobial peptides (SLPI, HNP 1â3, elafin, and LL-37) and neutrophil chemokines (CXCL1/GRO-α, CXCL2/GRO-ÎČ, CXCL5/ENA-78, CXCL6/GCP-2, CXCL7/NAP-2, and CXCL8/IL-8) were determined in bronchoalveolar lavage (BAL) fluid of 10 asthmatics and 15 normal controls taken before, at day four during and 6 weeks post-experimental infection. RESULTS: BAL HNP 1â3 and Elafin were higher, CXCL7/NAP-2 was lower in asthmatics compared with controls at day 4 (P = 0.035, P = 0.048, and P = 0.025, respectively). BAL HNP 1â3 and CXCL8/IL-8 were increased during infection (P = 0.003 and P = 0.011, respectively). There was a trend to increased BAL neutrophils at day 4 compared with baseline (P = 0.076). BAL HNP 1â3 was positively correlated with BAL neutrophil numbers at day 4. There were no correlations between clinical parameters and HNP1â3 or IL-8 levels. CONCLUSIONS: We propose that RV infection in asthma leads to increased release of CXCL8/IL-8, attracting neutrophils into the airways where they release HNP 1â3, which further enhances airway neutrophilia. Strategies to inhibit CXCL8/IL-8 may be useful in treatment of virus-induced asthma exacerbations
Vascular time-activity variation in patients undergoing 123I-MIBG myocardial scintigraphy: implications for quantification of cardiac and mediastinal uptake
For the quantification of cardiac (123)I-metaiodobenzylguanidine (MIBG) uptake, the mediastinum is commonly used as a reference region reflecting nonspecific background activity. However, variations in the quantity of vascular structures in the mediastinum and the rate of renal clearance of (123)I-MIBG from the blood pool may contribute to increased interindividual variation in uptake. This study examined the relationship between changes in heart (H) and mediastinal (M) counts and the change in vascular (123)I-MIBG activity, including the effect of renal function. Fifty-one subjects with ischemic heart disease underwent early (15 min) and late (4 h) anterior planar images of the chest following injection of (123)I-MIBG. Vascular (123)I-MIBG activity was determined from venous blood samples obtained at 2 min, 15 min, 35 min, and 4 h post-injection. From the vascular clearance curve of each subject, the mean blood counts/min per ml at the time of each acquisition and the slope of the clearance curve were determined. Renal function was expressed as the estimated creatinine clearance (e-CC) and the estimated glomerular filtration rate (e-GFR). Relations between H and M region of interest (ROI) counts/pixel, vascular activity, and renal function were then examined using linear regression. Changes in ROI activity ratios between early and late planar images could not be explained by blood activity, the slope of the vascular clearance curves, or estimates of renal function. At most 3% of the variation in image counts could be explained by changes in vascular activity (pâ=â0.104). The e-CC and e-GFR could at best explain approximately 1.5% of the variation in the slopes of the vascular clearance curve (pâ=â0.194). The change in measured H and M counts between early and late planar (123)I-MIBG images is unrelated to intravascular levels of the radiopharmaceutical. This suggests that changes in M counts are primarily due to decrease in soft tissue activity and scatter from the adjacent lung
Two interferon gamma release assays for predicting active tuberculosis: the UK PREDICT TB prognostic test study
National Institute for Health Research (NIHR
Spatial competition shapes the dynamic mutational landscape of normal esophageal epithelium.
During aging, progenitor cells acquire mutations, which may generate clones that colonize the surrounding tissue. By middle age, normal human tissues, including the esophageal epithelium (EE), become a patchwork of mutant clones. Despite their relevance for understanding aging and cancer, the processes that underpin mutational selection in normal tissues remain poorly understood. Here, we investigated this issue in the esophageal epithelium of mutagen-treated mice. Deep sequencing identified numerous mutant clones with multiple genes under positive selection, including Notch1, Notch2 and Trp53, which are also selected in human esophageal epithelium. Transgenic lineage tracing revealed strong clonal competition that evolved over time. Clone dynamics were consistent with a simple model in which the proliferative advantage conferred by positively selected mutations depends on the nature of the neighboring cells. When clones with similar competitive fitness collide, mutant cell fate reverts towards homeostasis, a constraint that explains how selection operates in normal-appearing epithelium.This work was supported by grants from the Wellcome Trust to the Wellcome SangerInstitute (098051 and 296194) and Cancer Research UK Programme Grants to P.H.J.(C609/A17257 and C609/A27326). G.P. is supported by a Talento program fellowship from Comunidad de Madrid. B.A.H. and M.W.J.H. are supported by the MedicalResearch Council (Grant-in-Aid to the MRC Cancer unit grant no. MC_UU_12022/9 and NIRG to B.A.H. grant no. MR/S000216/1). M.W.J.H. acknowledges support fromthe Harrison Watson Fund at Clare College, Cambridge. B.A.H. acknowledges support from the Royal Society (grant no. UF130039). I.M. is funded by Cancer Research UK (C57387/A21777). S.D. benefited from the award of an ESPOD fellowship, 2018-21, from the Wellcome Sanger Institute and the European Bioinformatics Institute EMBL-EBI
Circulating CD62E+ Microparticles and Cardiovascular Outcomes
BACKGROUND: Activated endothelial cells release plasma membrane submicron vesicles expressing CD62E (E-selectin) into blood, known as endothelial microparticles (EMPs). We studied whether the levels of endothelial microparticles expressing CD62E(+), CD31(+)/Annexin-V(+), or CD31(+)/CD42(-) predict cardiovascular outcomes in patients with stroke history. METHODS/PRINCIPAL FINDINGS: Patients with stroke history at least 3 months prior to enrolment were recruited. Peripheral blood EMP levels were measured by flow cytometry. Major cardiovascular events and death were monitored for 36 months. Three hundred patients were enrolled, of which 298 completed the study according to protocol. Major cardiovascular events occurred in 29 patients (9.7%). Nine patients died, five from cardiovascular causes. Cumulative event-free survival rates were lower in patients with high levels of CD62E(+) microparticles. Multivariate Cox regression analysis adjusted for cardiovascular risk factors, medications and stroke etiologic groups showed an association between a high CD62E(+) microparticle level and a risk of major cardiovascular events and hospitalization. Levels of other kinds of EMPs expressing CD31(+)/Annexin-V(+) or CD31(+)/CD42(-) markers were not predictive of cardiovascular outcomes. CONCLUSION: A high level of CD62E(+) microparticles is associated with cardiovascular events in patients with stroke history, suggesting that the systemic endothelial activation increases the risk for cardiovascular morbidities
Deformation analysis of a metropolis from C- to X-band PSI: proof-of-concept with Cosmo-Skymed over Rome, Italy
Stability of monuments and subsidence of residential
quarters in Rome (Italy) are depicted based on geospatial
analysis of more than 310,000 Persistent Scatterers (PS)
obtained from Stanford Method for Persistent Scatterers
(StaMPS) processing of 32 COSMO-SkyMed 3m-resolution
HH StripMap ascending mode scenes acquired between 21
March 2011 and 10 June 2013. COSMO-SkyMed PS
densities and associated displacement velocities are
compared with almost 20 years of historical C-band ERS-
1/2, ENVISAT and RADARSAT-1/2 imagery. Accounting
for differences in image processing algorithms and satellite
acquisition geometries, we assess the feasibility of ground
motion monitoring in big cities and metropolitan areas by
coupling newly acquired and legacy SAR in full time series.
Limitations and operational benefits of the transition from
medium resolution C-band to high resolution X-band PS
data are discussed, alongside the potential impact on the
management of expanding urban environments
Broadening symptom criteria improves early case identification in SARS-CoV-2 contacts
Background The success of case isolation and contact tracing for the control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission depends on the accuracy and speed of case identification. We assessed whether inclusion of additional symptoms alongside three canonical symptoms (CS), i.e. fever, cough and loss or change in smell or taste, could improve case definitions and accelerate case identification in SARS-CoV-2 contacts. Methods Two prospective longitudinal London (UK)-based cohorts of community SARS-CoV-2 contacts, recruited within 5â
days of exposure, provided independent training and test datasets. Infected and uninfected contacts completed daily symptom diaries from the earliest possible time-points. Diagnostic information gained by adding symptoms to the CS was quantified using likelihood ratios and area under the receiver operating characteristic curve. Improvements in sensitivity and time to detection were compared with penalties in terms of specificity and number needed to test. Results Of 529 contacts within two cohorts, 164 (31%) developed PCR-confirmed infection and 365 (69%) remained uninfected. In the training dataset (n=168), 29% of infected contacts did not report the CS. Four symptoms (sore throat, muscle aches, headache and appetite loss) were identified as early-predictors (EP) which added diagnostic value to the CS. The broadened symptom criterion ââ„1 of the CS, or â„2 of the EPâ identified PCR-positive contacts in the test dataset on average 2â
days earlier after exposure (p=0.07) than ââ„1 of the CSâ, with only modest reduction in specificity (5.7%). Conclusions Broadening symptom criteria to include individuals with at least two of muscle aches, headache, appetite loss and sore throat identifies more infections and reduces time to detection, providing greater opportunities to prevent SARS-CoV-2 transmission. Tweetable abstract @ERSpublication
The Activities of Current Antimalarial Drugs on the Life Cycle Stages of Plasmodium: A Comparative Study with Human and Rodent Parasites
Michael Delves and colleagues compare the activity of 50 current and experimental antimalarials against liver, sexual blood, and mosquito stages of selected human and nonhuman parasite species, including Plasmodium falciparum, Plasmodium berghei, and Plasmodium yoelii
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