158 research outputs found

    Ex vivo characterization of neuroinflammatory and neuroreceptor changes during epileptogenesis using candidate positron emission tomography biomarkers

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    Objective: Identification of patients at risk of developing epilepsy before the first spontaneous seizure may promote the development of preventive treatment providing opportunity to stop or slow down the disease. // Methods: As development of novel radiotracers and on‐site setup of existing radiotracers is highly time‐consuming and expensive, we used dual‐centre in vitro autoradiography as an approach to characterize the potential of innovative radiotracers in the context of epilepsy development. Using brain slices from the same group of rats, we aimed to characterise the evolution of neuroinflammation and expression of inhibitory and excitatory neuroreceptors during epileptogenesis using translational positron emission tomography (PET) tracers; 18F‐flumazenil (18F‐FMZ; GABAA receptor), 18F‐FPEB (metabotropic glutamate receptor 5; mGluR5), 18F‐flutriciclamide (translocator protein; TSPO, microglia activation) and 18F‐deprenyl (monoamine oxidase B, astroglia activation). Autoradiography images from selected time points after pilocarpine‐induced status epilepticus (SE; baseline, 24 and 48 hours, 5, 10 and 15 days and 6 and 12‐14 weeks after SE) were normalized to a calibration curve, co‐registered to an MRI‐based 2D region‐of‐interest atlas, and activity concentration (Bq/mm2) was calculated. // Results: In epileptogenesis‐associated brain regions, 18F‐FMZ and 18F‐FPEB showed an early decrease after SE. 18F‐FMZ decrease was maintained in the latent phase and further reduced in the chronic epileptic animals, while 18F‐FPEB signal recovered from day 10, reaching baseline levels in chronic epilepsy. 18F‐flutriciclamide showed an increase of activated microglia at 24 hours after SE, peaking at 5‐15 days and decreasing during the chronic phase. On the other hand, 18F‐deprenyl autoradiography showed late astrogliosis, peaking in the chronic phase. // Significance: Autoradiography revealed different evolution of the selected targets during epileptogenesis. Our results suggest an advantage of combined imaging of inter‐related targets like glutamate and GABAA receptors, or microglia and astrocyte activation, in order to identify important interactions, especially when using PET imaging for the evaluation of novel treatments

    Urinary Iodine, Perchlorate, and Thiocyanate Concentrations in U.S. Lactating Women

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    Background: Iodine is an essential micronutrient for thyroid hormone production. Adequate iodine intake and normal thyroid function are important during early development, and breastfed infants rely on maternal iodine excreted in breast milk for their iodine nutrition. The proportion of women in the United States of childbearing age with urinary iodine concentration (UIC) <50 Όg/L has been increasing, and a subset of lactating women may have inadequate iodine intake. UIC may also be influenced by environmental exposure to perchlorate and thiocyanate, competitive inhibitors of iodine transport into thyroid, and lactating mammary glands. Data regarding UIC in U.S. lactating women are limited. To adequately assess the iodine sufficiency of lactating women and potential associations with environmental perchlorate and thiocyanate exposure, we conducted a multicenter, cross-sectional study of urinary iodine, perchlorate, and thiocyanate concentrations in healthy U.S. lactating women. Methods: Lactating women ≄18 years of age were recruited from three U.S. geographic regions: California, Massachusetts, and Ohio/Illinois from November 2008 to June 2016. Demographic information and multivitamin supplements use were obtained. Iodine, perchlorate, and thiocyanate levels were measured from spot urine samples. Correlations between urinary iodine, perchlorate, and thiocyanate levels were determined using Spearman's rank correlation. Multivariable regression models were used to assess predictors of urinary iodine, perchlorate, and thiocyanate levels, and UIC <100 Όg/L. Results: A total of 376 subjects (≄125 from each geographic region) were included in the final analyses [mean (SD) age 31.1 (5.6) years, 37% white, 31% black, and 11% Hispanic]. Seventy-seven percent used multivitamin supplements, 5% reported active cigarette smoking, and 45% were exclusively breastfeeding. Median urinary iodine, perchlorate, and thiocyanate concentrations were 143 Όg/L, 3.1 Όg/L, and 514 Όg/L, respectively. One-third of women had UIC <100 Όg/L. Spot urinary iodine, perchlorate, and thiocyanate levels all significantly positively correlated to each other. No significant predictors of UIC, UIC <100 Όg/L, or urinary perchlorate levels were identified. Smoking, race/ethnicity, and marital status were significant predictors of urinary thiocyanate levels. Conclusion: Lactating women in three U.S. geographic regions are iodine sufficient with an overall median UIC of 143 Όg/L. Given ubiquitous exposure to perchlorate and thiocyanate, adequate iodine nutrition should be emphasized, along with consideration to decrease these exposures in lactating women to protect developing infants

    Tocilizumab in systemic sclerosis: a randomised, double-blind, placebo-controlled, phase 3 trial

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    BACKGROUND: A phase 2 trial of tocilizumab showed preliminary evidence of efficacy in systemic sclerosis. We assessed skin fibrosis and systemic sclerosis-associated interstitial lung disease (SSc-ILD) in a phase 3 trial to investigate the safety and efficacy of tocilizumab, an anti-interleukin-6 receptor antibody, in the treatment of systemic sclerosis. METHODS: In this multicentre, randomised, double-blind, placebo-controlled, phase 3 trial, participants were recruited from 75 sites in 20 countries across Europe, North America, Latin America, and Japan. Adults with diffuse cutaneous systemic sclerosis for 60 months or less and a modified Rodnan skin score (mRSS) of 10-35 at screening were randomly assigned (1:1) with a voice-web-response system to receive subcutaneous tocilizumab 162 mg or placebo weekly for 48 weeks, stratified by IL-6 levels; participants and investigators were masked to treatment group. The primary endpoint was the difference in change from baseline to week 48 in mRSS. Percentage of predicted forced vital capacity (FVC% predicted) at week 48, time to treatment failure, and patient-reported and physician-reported outcomes were secondary endpoints. This trial is registered with ClinicalTrials.gov (number NCT02453256) and is closed to accrual. FINDINGS: Between Nov 20, 2015, and Feb 14, 2017, 210 individuals were randomly assigned to receive tocilizumab (n=104) or placebo (n=106). In the intention-to-treat population, least squares mean [LSM] change from baseline to week 48 in mRSS was -6·14 for tocilizumab and -4·41 for placebo (adjusted difference -1·73 [95% CI -3·78 to 0·32]; p=0·10). The shift in distribution of change from baseline in FVC% predicted at week 48 favoured tocilizumab (van Elteren nominal p=0·002 vs placebo), with a difference in LSM of 4·2 (95% CI 2·0-6·4; nominal p=0·0002), as did time to treatment failure (hazard ratio 0·63 [95% CI 0·37-1·06]; nominal p=0·08). Change in LSM from baseline to week 48 in Health Assessment Questionnaire-Disability Index and in patient-global and physician-global visual analogue scale assessments did not differ between tocilizumab and placebo. In the safety set, infections were the most common adverse events (54 [52%] of 104 participants in the tocilizumab group, 53 [50%] of 106 in the placebo group). Serious adverse events were reported in 13 participants treated with tocilizumab and 18 with placebo, primarily infections (three events, eight events) and cardiac events (two events, seven events). INTERPRETATION: The primary skin fibrosis endpoint was not met. Findings for the secondary endpoint of FVC% predicted indicate that tocilizumab might preserve lung function in people with early SSc-ILD and elevated acute-phase reactants. Safety was consistent with the known profile of tocilizumab. FUNDING: F Hoffmann-La Roche Ltd

    Lupin protein isolate versus casein modifies cholesterol excretion and mRNA expression of intestinal sterol transporters in a pig model

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    Abstract Background Lupin proteins exert hypocholesterolemic effects in man and animals, although the underlying mechanism remains uncertain. Herein we investigated whether lupin proteins compared to casein modulate sterol excretion and mRNA expression of intestinal sterol transporters by use of pigs as an animal model with similar lipid metabolism as humans, and cellular cholesterol-uptake by Caco-2 cells. Methods Two groups of pigs were fed cholesterol-containing diets with either 230 g/kg of lupin protein isolate from L. angustifolius or 230 g/kg casein, for 4 weeks. Faeces were collected quantitatively over a 5 d period for analysis of neutral sterols and bile acids by gas chromatographically methods. The mRNA abundances of intestinal lipid transporters were analysed by real-time RT-PCR. Cholesterol-uptake studies were performed with Caco-2 cells that were incubated with lupin conglutin \u3b3, phytate, ezetimibe or albumin in the presence of labelled [4-14C]-cholesterol. Results Pigs fed the lupin protein isolate revealed lower cholesterol concentrations in total plasma, LDL and HDL than pigs fed casein (P < 0.05). Analysis of faeces revealed a higher output of cholesterol in pigs that were fed lupin protein isolate compared to pigs that received casein (+57.1%; P < 0.05). Relative mRNA concentrations of intestinal sterol transporters involved in cholesterol absorption (Niemann-Pick C1-like 1, scavenger receptor class B, type 1) were lower in pigs fed lupin protein isolate than in those who received casein (P < 0.05). In vitro data showed that phytate was capable of reducing the uptake of labelled [4-14C]-cholesterol into the Caco-2 cells to the same extend as ezetimibe when compared to control ( 1220.5% vs. 1221.1%; P < 0.05). Conclusions Data reveal that the cholesterol-lowering effect of lupin protein isolate is attributable to an increased faecal output of cholesterol and a reduced intestinal uptake of cholesterol. The findings indicate phytate as a possible biofunctional ingredient of lupin protein isolate.Background: Lupin proteins exert hypocholesterolemic effects in man and animals, although the underlying mechanism remains uncertain. Herein we investigated whether lupin proteins compared to casein modulate sterol excretion and mRNA expression of intestinal sterol transporters by use of pigs as an animal model with similar lipid metabolism as humans, and cellular cholesterol-uptake by Caco-2 cells. Methods. Two groups of pigs were fed cholesterol-containing diets with either 230 g/kg of lupin protein isolate from L. angustifolius or 230 g/kg casein, for 4 weeks. Faeces were collected quantitatively over a 5 d period for analysis of neutral sterols and bile acids by gas chromatographically methods. The mRNA abundances of intestinal lipid transporters were analysed by real-time RT-PCR. Cholesterol-uptake studies were performed with Caco-2 cells that were incubated with lupin conglutin \u3b3, phytate, ezetimibe or albumin in the presence of labelled [4- 14C]-cholesterol. Results: Pigs fed the lupin protein isolate revealed lower cholesterol concentrations in total plasma, LDL and HDL than pigs fed casein (P < 0.05). Analysis of faeces revealed a higher output of cholesterol in pigs that were fed lupin protein isolate compared to pigs that received casein (+57.1%; P < 0.05). Relative mRNA concentrations of intestinal sterol transporters involved in cholesterol absorption (Niemann-Pick C1-like 1, scavenger receptor class B, type 1) were lower in pigs fed lupin protein isolate than in those who received casein (P < 0.05). In vitro data showed that phytate was capable of reducing the uptake of labelled [4- 14C]-cholesterol into the Caco-2 cells to the same extend as ezetimibe when compared to control (-20.5% vs. -21.1%; P < 0.05). Conclusions: Data reveal that the cholesterol-lowering effect of lupin protein isolate is attributable to an increased faecal output of cholesterol and a reduced intestinal uptake of cholesterol. The findings indicate phytate as a possible biofunctional ingredient of lupin protein isolate

    Therapeutic interleukin-6 blockade reverses transforming growth factor-beta pathway activation in dermal fibroblasts: insights from the faSScinate clinical trial in systemic sclerosis

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    OBJECTIVES: Skin fibrosis mediated by activated dermal fibroblasts is a hallmark of systemic sclerosis (SSc), especially in the subset of patients with diffuse disease. Transforming growth factor-beta (TGFÎČ) and interleukin-6 (IL-6) are key candidate mediators in SSc. Our aim was to elucidate the specific effect of IL-6 pathway blockade on the biology of SSc fibroblasts in vivo by using samples from a unique clinical experiment-the faSScinate study-in which patients with SSc were treated for 24 weeks with tocilizumab (TCZ), an IL-6 receptor-α inhibitor. METHODS: We analysed the molecular, functional and genomic characteristics of explant fibroblasts cultured from matched skin biopsy samples collected at baseline and at week 24 from 12 patients receiving placebo (n=6) or TCZ (n=6) and compared these with matched healthy control fibroblast strains. RESULTS: The hallmark functional and molecular-activated phenotype was defined in SSc samples and was stable over 24 weeks in placebo-treated cases. RNA sequencing analysis robustly defined key dysregulated pathways likely to drive SSc fibroblast activation in vivo. Treatment with TCZ for 24 weeks profoundly altered the biological characteristics of explant dermal fibroblasts by normalising functional properties and reversing gene expression profiles dominated by TGFÎČ-regulated genes and molecular pathways. CONCLUSIONS: We demonstrated the exceptional value of using explant dermal fibroblast cultures from a well-designed trial in SSc to provide a molecular framework linking IL-6 to key profibrotic pathways. The profound impact of IL-6R blockade on the activated fibroblast phenotype highlights the potential of IL-6 as a therapeutic target in SSc and other fibrotic diseases. TRIAL REGISTRATION NUMBER: NCT01532869; Post-results

    The host metabolite D-serine contributes to bacterial niche specificity through gene selection

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    Escherichia coli comprise a diverse array of both commensals and niche-specific pathotypes. The ability to cause disease results from both carriage of specific virulence factors and regulatory control of these via environmental stimuli. Moreover, host metabolites further refine the response of bacteria to their environment and can dramatically affect the outcome of the host–pathogen interaction. Here, we demonstrate that the host metabolite, D-serine, selectively affects gene expression in E. coli O157:H7. Transcriptomic profiling showed exposure to D-serine results in activation of the SOS response and suppresses expression of the Type 3 Secretion System (T3SS) used to attach to host cells. We also show that concurrent carriage of both the D-serine tolerance locus (dsdCXA) and the locus of enterocyte effacement pathogenicity island encoding a T3SS is extremely rare, a genotype that we attribute to an ‘evolutionary incompatibility’ between the two loci. This study demonstrates the importance of co-operation between both core and pathogenic genetic elements in defining niche specificity

    Molecular control of sucrose utilization in Escherichia coli W, an efficient sucrose-utilizing strain

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    Sucrose is an industrially important carbon source for microbial fermentation. Sucrose utilization in Escherichia coli, however, is poorly understood, and most industrial strains cannot utilize sucrose. The roles of the chromosomally encoded sucrose catabolism (csc) genes in E. coli W were examined by knockout and overexpression experiments. At low sucrose concentrations, the csc genes are repressed and cells cannot grow. Removal of either the repressor protein (cscR) or the fructokinase (cscK) gene facilitated derepression. Furthermore, combinatorial knockout of cscR and cscK conferred an improved growth rate on low sucrose. The invertase (cscA) and sucrose transporter (cscB) genes are essential for sucrose catabolism in E. coli W, demonstrating that no other genes can provide sucrose transport or inversion activities. However, cscK is not essential for sucrose utilization. Fructose is excreted into the medium by the cscK-knockout strain in the presence of high sucrose, whereas at low sucrose (when carbon availability is limiting), fructose is utilized by the cell. Overexpression of cscA, cscAK, or cscAB could complement the W Delta cscRKAB knockout mutant or confer growth on a K-12 strain which could not naturally utilize sucrose. However, phenotypic stability and relatively good growth rates were observed in the K-12 strain only when overexpressing cscAB, and full growth rate complementation in W Delta cscRKA Balso required cscAB. Our understanding of sucrose utilization can be used to improve E. coli Wand engineer sucrose utilization in strains which do not naturally utilize sucrose, allowing substitution of sucrose for other, less desirable carbon sources in industrial fermentations

    Integrative inference of gene-regulatory networks in Escherichia coli using information theoretic concepts and sequence analysis

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    <p>Abstract</p> <p>Background</p> <p>Although <it>Escherichia coli </it>is one of the best studied model organisms, a comprehensive understanding of its gene regulation is not yet achieved. There exist many approaches to reconstruct regulatory interaction networks from gene expression experiments. Mutual information based approaches are most useful for large-scale network inference.</p> <p>Results</p> <p>We used a three-step approach in which we combined gene regulatory network inference based on directed information (DTI) and sequence analysis. DTI values were calculated on a set of gene expression profiles from 19 time course experiments extracted from the Many Microbes Microarray Database. Focusing on influences between pairs of genes in which one partner encodes a transcription factor (TF) we derived a network which contains 878 TF - gene interactions of which 166 are known according to RegulonDB. Afterward, we selected a subset of 109 interactions that could be confirmed by the presence of a phylogenetically conserved binding site of the respective regulator. By this second step, the fraction of known interactions increased from 19% to 60%. In the last step, we checked the 44 of the 109 interactions not yet included in RegulonDB for functional relationships between the regulator and the target and, thus, obtained ten TF - target gene interactions. Five of them concern the regulator LexA and have already been reported in the literature. The remaining five influences describe regulations by Fis (with two novel targets), PhdR, PhoP, and KdgR. For the validation of our approach, one of them, the regulation of lipoate synthase (LipA) by the pyruvate-sensing pyruvate dehydrogenate repressor (PdhR), was experimentally checked and confirmed.</p> <p>Conclusions</p> <p>We predicted a set of five novel TF - target gene interactions in <it>E. coli</it>. One of them, the regulation of <it>lipA </it>by the transcriptional regulator PdhR was validated experimentally. Furthermore, we developed DTInfer, a new R-package for the inference of gene-regulatory networks from microarrays using directed information.</p

    Filgotinib versus placebo or adalimumab in patients with rheumatoid arthritis and inadequate response to methotrexate: a phase III randomised clinical trial

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    Objective To evaluate the efficacy and safety of the Janus kinase-1-preferential inhibitor filgotinib versus placebo or tumour necrosis factor-alpha inhibitor therapy in patients with active rheumatoid arthritis (RA) despite ongoing treatment with methotrexate (MTX).Methods This 52-week, multicentre, double-blind, placebo-controlled and active-controlled phase III trial evaluated once-daily oral filgotinib in patients with RA randomised 3:3:2:3 to filgotinib 200 mg (FIL200) or filgotinib 100 mg (FIL100), subcutaneous adalimumab 40 mg biweekly, or placebo (through week 24), all with stable weekly background MTX. The primary endpoint was the proportion of patients achieving 20% improvement in American College of Rheumatology criteria (ACR20) at week 12. Additional efficacy outcomes were assessed sequentially. Safety was assessed from adverse events and laboratory abnormalities.Results The proportion of patients (n=1755 randomised and treated) achieving ACR20 at week 12 was significantly higher for FIL200 (76.6%) and FIL100 (69.8%) versus placebo (49.9%; treatment difference (95% CI), 26.7% (20.6% to 32.8%) and 19.9% (13.6% to 26.2%), respectively; both p<0.001). Filgotinib was superior to placebo in key secondary endpoints assessing RA signs and symptoms, physical function and structural damage. FIL200 was non-inferior to adalimumab in terms of Disease Activity Score in 28 joints with C reactive protein <= 3.2 at week 12 (p<0.001); FIL100 did not achieve non-inferiority. Adverse events and laboratory abnormalities were comparable among active treatment arms.Conclusions Filgotinib improved RA signs and symptoms, improved physical function, inhibited radiographic progression and was well tolerated in patients with RA with inadequate response to MTX. FIL200 was non-inferior to adalimumab.Pathophysiology and treatment of rheumatic disease
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