Development and set-up of a portable device to monitor airway exhalation and deposition of particulate matter

The aim of this study was to assess and monitor airway exhalation and deposition of particulate matter (PM). After standardizing inspiratory/expiratory flow and volumes, a novel device was tested on a group of 20 volunteers and in a field study on workers exposed to cristobalite. Both male and female subjects showed a higher percentage of deposition in the 0.5?μm channel than in the 0.3?μm channel on a laser particle counter, but it was higher in the males because of their higher exhaled lung volumes. The device was tested on a wider range of particles (0.3–0.5–1.0–2.5?μm) in the cristobalite productive division. The device has low intrasubject variability and good reproducibility, with geometric mean of %CV?相似文献   

Efficient plasmid-mediated gene transfection of ovine bone marrow mesenchymal stromal cells

Background aimsGiven the close similarity between ovine and human cardiomyocytes, sheep models of myocardial infarction and heart failure are increasingly used in studies of stem cell-mediated heart regeneration. In these studies, mesenchymal stromal cells (MSCs) are frequently employed. To enhance the paracrine effects of these MSCs, ex vivo transfection with genes encoding growth factors has been proposed. Although viral vectors exhibit higher transfection efficiency than plasmids, they entail the risks of uncontrolled transgene expression and immune reactions that preclude repeated administration. Our aim was to optimize the efficiency of plasmid-mediated transfection of ovine MSCs, while preserving cell viability.MethodsVarying amounts of diverse cationic lipids were used to obtain the reagent-to-DNA mass ratio showing highest luciferase activity. Transfection efficiency (flow cytometry) was tested on plasmid-green fluorescent protein-transfected MSCs at increasing DNA mass.ResultsLipofectamine LTX 5 μL and Plus reagent 4 μL with 2 μg of DNA yielded 42.3 ± 4.7% transfection efficiency, while preserving cell viability. Using these transfection conditions, we transfected MSCs with a plasmid encoding human vascular endothelial growth factor (VEGF) and found high VEGF protein concentrations in the culture supernatant from day 2 (1968 ± 324 pg/mL per μg DNA) through at least day 12 (888 ± 386 pg/mL per μg DNA) after transfection.ConclusionsPlasmid-mediated transfection of ovine MSCs to over-express paracrine heart-regenerative growth factors is feasible and efficient and overcomes the risks and limitations associated with the use of viral vectors.     

Cigarette smoke metabolically promotes cancer,via autophagy and premature aging in the host stromal microenvironment

Cigarette smoke has been directly implicated in the disease pathogenesis of a plethora of different human cancer subtypes, including breast cancers. The prevailing view is that cigarette smoke acts as a mutagen and DNA damaging agent in normal epithelial cells, driving tumor initiation. However, its potential negative metabolic effects on the normal stromal microenvironment have been largely ignored. Here, we propose a new mechanism by which carcinogen-rich cigarette smoke may promote cancer growth, by metabolically “fertilizing” the host microenvironment. More specifically, we show that cigarette smoke exposure is indeed sufficient to drive the onset of the cancer-associated fibroblast phenotype via the induction of DNA damage, autophagy and mitophagy in the tumor stroma. In turn, cigarette smoke exposure induces premature aging and mitochondrial dysfunction in stromal fibroblasts, leading to the secretion of high-energy mitochondrial fuels, such as L-lactate and ketone bodies. Hence, cigarette smoke induces catabolism in the local microenvironment, directly fueling oxidative mitochondrial metabolism (OXPHOS) in neighboring epithelial cancer cells, actively promoting anabolic tumor growth. Remarkably, these autophagic-senescent fibroblasts increased breast cancer tumor growth in vivo by up to 4-fold. Importantly, we show that cigarette smoke-induced metabolic reprogramming of the fibroblastic stroma occurs independently of tumor neo-angiogenesis. We discuss the possible implications of our current findings for the prevention of aging-associated human diseases and, especially, common epithelial cancers, as we show that cigarette smoke can systemically accelerate aging in the host microenvironment. Finally, our current findings are consistent with the idea that cigarette smoke induces the “reverse Warburg effect,” thereby fueling “two-compartment tumor metabolism” and oxidative mitochondrial metabolism in epithelial cancer cells.     

CpG Methylation Changes within the IL2RA Promoter in Type 1 Diabetes of Childhood Onset

None of the polymorphic variants of the IL2RA gene found associated with Type 1 Diabetes (T1D) was shown to have a functional effect. To test if the epigenetic variation could play a role at this locus, we studied the methylation of 6 CpGs located within the proximal promoter of IL2RA gene in 252 T1D patients compared with 286 age-matched controls. We found that DNA methylation at CpGs −373 and −456 was slightly but significantly higher in patients than in controls (40.4±4.6 vs 38.3±5.4, p = 1.4E4; 91.4±2.8 vs 89.5±5.3, p = 1.8E-6), while other CpG showed a strictly comparable methylation. Among 106 single nucleotide polymorphisms (SNPs) located in the neighboring 180kb region, we found that 28 SNPs were associated with DNA methylation at CpG −373. Sixteen of these SNPs were known to be associated with T1D. Our findings suggest that the effect of IL2RA risk alleles on T1D may be partially mediated through epigenetic changes.     

Progression,Symptoms and Psychosocial Concerns among Those Severely Affected by Multiple Sclerosis: A Mixed-Methods Cross-Sectional Study of Black Caribbean and White British People

Objective

Multiple sclerosis is now more common among minority ethnic groups in the UK but little is known about their experiences, especially in advanced stages. We examine disease progression, symptoms and psychosocial concerns among Black Caribbean (BC) and White British (WB) people severely affected by MS.

Design

Mixed methods study of 43 BC and 43 WB people with MS (PwMS) with an Expanded Disability Status Scale (EDSS) ≥6 involving data from in clinical records, face-to-face structured interviews and a nested-qualitative component. Progression Index (PI) and Multiple Sclerosis Severity Score (MSSS) were calculated. To control for selection bias, propensity scores were derived for each patient and adjusted for in the comparative statistical analysis; qualitative data were analysed using the framework approach.

Results

Median EDSS for both groups was (6.5; range: 6.0–9.0). Progression Index (PI) and Multiple Sclerosis Severity Score (MSSS) based on neurological assessment of current EDSS scores identified BC PwMS were more likely to have aggressive disease (PI F = 4.04, p = 0.048, MSSS F = 10.30, p<0.001). Patients’ reports of the time required to reach levels of functional decline equivalent to different EDSS levels varied by group; EDSS 4: BC 2.7 years v/s WB 10.2 years (U = 258.50, p = 0.013), EDSS 6∶6.1 years BC v/s WB 12.7 years (U = 535.500, p = 0.011), EDSS 8: BC 8.7 years v/s WB 10.2 years. Both groups reported high symptom burden. BC PwMS were more cognitively impaired than WB PwMS (F = 9.65, p = 0.003). Thematic analysis of qualitative interviews provides correspondence with quantitative findings; more BC than WB PwMS referred to feelings of extreme frustration and unresolved loss/confusion associated with their rapidly advancing disease. The interviews also reveal the centrality, meanings and impact of common MS-related symptoms.

Conclusions

Delays in diagnosis should be avoided and more frequent reviews may be justified by healthcare services. Culturally acceptable interventions to better support people who perceive MS as an assault on identity should be developed to help them achieve normalisation and enhance self-identity.