ESCRT-III-associated proteins and spastin inhibit protrudin-dependent polarised membrane traffic

Funder: National Institute for Health Research; doi: http://dx.doi.org/10.13039/501100000272Funder: Gates Cambridge Trust; doi: http://dx.doi.org/10.13039/501100005370Abstract: Mutations in the gene encoding the microtubule severing ATPase spastin are the most frequent cause of hereditary spastic paraplegia, a genetic condition characterised by length-dependent axonal degeneration. Here, we show that HeLa cells lacking spastin and embryonic fibroblasts from a spastin knock-in mouse model become highly polarised and develop cellular protrusions. In HeLa cells, this phenotype was rescued by wild-type spastin, but not by forms unable to sever microtubules or interact with endosomal ESCRT-III proteins. Cells lacking the spastin-interacting ESCRT-III-associated proteins IST1 or CHMP1B also developed protrusions. The protrusion phenotype required protrudin, a RAB-interacting protein that interacts with spastin and localises to ER–endosome contact sites, where it promotes KIF5-dependent endosomal motility to protrusions. Consistent with this, the protrusion phenotype in cells lacking spastin also required KIF5. Lack or mutation of spastin resulted in functional consequences for receptor traffic of a pathway implicated in HSP, as Bone Morphogenetic Protein receptor distribution became polarised. Our results, therefore, identify a novel role for ESCRT-III proteins and spastin in regulating polarised membrane traffic

Diesel exhaust particulate induces pulmonary and systemic inflammation in rats without impairing endothelial function ex vivo or in vivo

<p>Abstract</p> <p>Background</p> <p>Inhalation of diesel exhaust impairs vascular function in man, by a mechanism that has yet to be fully established. We hypothesised that pulmonary exposure to diesel exhaust particles (DEP) would cause endothelial dysfunction in rats as a consequence of pulmonary and systemic inflammation.</p> <p>Methods</p> <p>Wistar rats were exposed to DEP (0.5 mg) or saline vehicle by intratracheal instillation and hind-limb blood flow, blood pressure and heart rate were monitored <it>in situ </it>6 or 24 h after exposure. Vascular function was tested by administration of the endothelium-dependent vasodilator acetylcholine (ACh) and the endothelium-independent vasodilator sodium nitroprusside (SNP) <it>in vivo </it>and <it>ex vivo </it>in isolated rings of thoracic aorta, femoral and mesenteric artery from DEP exposed rats. Bronchoalveolar lavage fluid (BALF) and blood plasma were collected to assess pulmonary (cell differentials, protein levels & interleukin-6 (IL-6)) and systemic (IL-6), tumour necrosis factor alpha (TNFα) and C-reactive protein (CRP)) inflammation, respectively.</p> <p>Results</p> <p>DEP instillation increased cell counts, total protein and IL-6 in BALF 6 h after exposure, while levels of IL-6 and TNFα were only raised in blood 24 h after DEP exposure. DEP had no effect on the increased hind-limb blood flow induced by ACh <it>in vivo </it>at 6 or 24 h. However, responses to SNP were impaired at both time points. In contrast, <it>ex vivo </it>responses to ACh and SNP were unaltered in arteries isolated from rats exposed to DEP.</p> <p>Conclusions</p> <p>Exposure of rats to DEP induces both pulmonary and systemic inflammation, but does not modify endothelium-dependent vasodilatation. Other mechanisms <it>in vivo </it>limit dilator responses to SNP and these require further investigation.</p

Laboring to Mother in the Context of Past Trauma: The Transition to Motherhood

The occurrence of interpersonal trauma is a reality for many women, with effects that often persist long after the traumatic events end. The purpose of this feminist grounded theory study was to examine how past trauma shaped the lives of women as they became new mothers. We recruited a purposive sample of 32 women from two Canadian communities and conducted semistructured, dialogic interviews during the second trimester of pregnancy. We analyzed data using thematic content analytic methods, including open coding whereby we read transcripts line by line and applied codes to portions of text that illustrated concepts or themes. The substantive grounded theory, “laboring to mother in the context of past trauma,” describes the exceedingly difficult emotional and cognitive work undertaken by pregnant women with histories of trauma as they anticipate becoming mothers. In this article, we present key components of the theory and offer recommendations for health and social service providers

The impact of behavioral and mental health risk assessments on goal setting in primary care

Patient-centered health risk assessments (HRAs) that screen for unhealthy behaviors, prioritize concerns, and provide feedback may improve counseling, goal setting, and health. To evaluate the effectiveness of routinely administering a patient-centered HRA, My Own Health Report, for diet, exercise, smoking, alcohol, drug use, stress, depression, anxiety, and sleep, 18 primary care practices were randomized to ask patients to complete My Own Health Report (MOHR) before an office visit (intervention) or continue usual care (control). Intervention practice patients were more likely than control practice patients to be asked about each of eight risks (range of differences 5.3-15.8 %, p < 0.001), set goals for six risks (range of differences 3.8-16.6 %, p < 0.01), and improve five risks (range of differences 5.4-13.6 %, p < 0.01). Compared to controls, intervention patients felt clinicians cared more for them and showed more interest in their concerns. Patient-centered health risk assessments improve screening and goal setting.Trial RegistrationClinicaltrials.gov identifier: NCT01825746

Platelet activation independent of pulmonary inflammation contributes to diesel exhaust particulate-induced promotion of arterial thrombosis

BACKGROUND: Accelerated thrombus formation induced by exposure to combustion-derived air pollution has been linked to alterations in endogenous fibrinolysis and platelet activation in response to pulmonary and systemic inflammation. We hypothesised that mechanisms independent of inflammation contribute to accelerated thrombus formation following exposure to diesel exhaust particles (DEP). METHODS: Thrombosis in rats was assessed 2, 6 and 24 h after administration of DEP, carbon black (CB; control carbon nanoparticle), DQ12 quartz microparticles (to induce pulmonary inflammation) or saline (vehicle) by either intra-tracheal instillation (0.5 mg, except Quartz; 0.125 mg) or intravenous injection (0.5 mg/kg). Thrombogenicity was assessed by carotid artery occlusion, fibrinolytic variables and platelet-monocyte aggregates. Measures of inflammation were determined in plasma and bronchoalveolar lavage fluid. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI)-1 were measured following direct in vitro exposure of human umbilical vein endothelial cells (HUVECs) to DEP (10–150 μg/mL). RESULTS: Instillation of DEP reduced the time to thrombotic occlusion in vivo, coinciding with the peak of DEP-induced pulmonary inflammation (6 h). CB and DQ12 produced greater inflammation than DEP but did not alter time to thrombotic occlusion. Intravenous DEP produced an earlier (2 h) acceleration of thrombosis (as did CB) without pulmonary or systemic inflammation. DEP inhibited t-PA and PAI-1 release from HUVECs, and reduced the t-PA/PAI-1 ratio in vivo; similar effects in vivo were seen with CB and DQ12. DEP, but not CB or DQ12, increased platelet-monocyte aggregates. CONCLUSION: DEP accelerates arterial thrombus formation through increased platelet activation. This effect is dissociated from pulmonary and systemic inflammation and from impaired fibrinolytic function. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12989-016-0116-x) contains supplementary material, which is available to authorized users

Lung cancer stage-shift following a symptom awareness campaign

Background: Lung cancer outcomes in the UK are worse than in many other developed nations. Symptom awareness campaigns aim to diagnose patients at an earlier stage to improve cancer outcomes. Methods: An early diagnosis campaign for lung cancer commenced in Leeds, UK in 2011 comprising public and primary-care facing components. Rates of community referral for chest X-ray and lung cancer stage (TNM seventh edition) at presentation were collected from 2008 to 2015. Linear trends were assessed by χ2 test for trend in proportions. Headline figures are presented for the 3 years pre-campaign (2008–2010) and the three most recent years for which data are available during the campaign (2013–2015). Findings: Community-ordered chest X-ray rates per year increased from 18 909 in 2008–2010 to 34 194 in 2013–2015 (80.8% increase). A significant stage shift towards earlier stage lung cancer was seen (χ2(1)=32.2, p<0.0001). There was an 8.8 percentage point increase in the proportion of patients diagnosed with stage I/II lung cancer (26.5% pre-campaign vs 35.3% during campaign) and a 9.3% reduction in the absolute number of patients diagnosed with stage III/IV disease (1254 pre-campaign vs 1137 during campaign). Interpretation: This is the largest described lung cancer stage-shift in association with a symptom awareness campaign. A causal link between the campaign and stage-shift cannot be proven but appears plausible. Limitations of the analysis include a lack of contemporary control population

Diesel exhaust particulate increases the size and complexity of lesions in atherosclerotic mice

Abstract Objective Diesel exhaust particulate (DEP), a major component of urban air pollution, has been linked to atherogenesis and precipitation of myocardial infarction. We hypothesized that DEP exposure would increase and destabilise atherosclerotic lesions in apolipoprotein E deficient (ApoE−/−) mice. Methods ApoE−/− mice were fed a ‘Western diet’ (8 weeks) to induce ‘complex’ atherosclerotic plaques, with parallel experiments in normal chow fed wild-type mice. During the last 4 weeks of feeding, mice received twice weekly instillation (oropharyngeal aspiration) of 35 μL DEP (1 mg/mL, SRM-2975) or vehicle (saline). Atherosclerotic burden was assessed by en-face staining of the thoracic aorta and histological examination of the brachiocephalic artery. Results Brachiocephalic atherosclerotic plaques were larger in ApoE−/− mice treated with DEP (59±10%) than in controls (32±7%; P = 0.017). In addition, DEP-treated mice had more plaques per section of artery (2.4±0.2 vs 1.8±0.2; P = 0.048) and buried fibrous layers (1.2±0.2 vs 0.4±0.1; P = 0.028). These changes were associated with lung inflammation and increased antioxidant gene expression in the liver, but not with changes in endothelial function, plasma lipids or systemic inflammation. Conclusions Increased atherosclerosis is caused by the particulate component of diesel exhaust producing advanced plaques with a potentially more vulnerable phenotype. These results are consistent with the suggestion that removal of the particulate component would reduce the adverse cardiovascular effects of diesel exhaust