Trehalose is required for the acquisition of tolerance to a variety of stresses in the filamentous fungus Aspergillus nidulans

Trehalose is a non-reducing disaccharide found at high concentrations in Aspergillus nidulans conidia and rapidly degraded upon induction of conidial germination. Furthermore, trehalose is accumulated in response to a heat shock or to an oxidative shock. The authors have characterized the A. nidulans tpsA gene encoding trehalose-6-phosphate synthase, which catalyses the first step in trehalose biosynthesis. Expression of tpsA in a Saccharomyces cerevisiae tps1 mutant revealed that the tpsA gene product is a functional equivalent of the yeast Tps1 trehalose-6-phosphate synthase. The A. nidulans tpsA-null mutant does not produce trehalose during conidiation or in response to various stress conditions. While germlings of the tpsA mutant show an increased sensitivity to moderate stress conditions (growth at 45 °C or in the presence of 2 mM H2O2), they display a response to severe stress (60 min at 50 °C or in the presence of 100 mM H2O2) similar to that of wild-type germlings. Furthermore, conidia of the tpsA mutant show a rapid loss of viability upon storage. These results are consistent with a role of trehalose in the acquisition of stress tolerance. Inactivation of the tpsA gene also results in increased steady-state levels of sugar phosphates but does not prevent growth on rapidly metabolizable carbon sources (glucose, fructose) as seen in Saccharomyces cerevisiae. This suggests that trehalose 6-phosphate is a physiological inhibitor of hexokinase but that this control is not essential for proper glycolytic flux in A. nidulans. Interestingly, tpsA transcription is not induced in response to heat shock or during conidiation, indicating that trehalose accumulation is probably due to a post-translational activation process of the trehalose 6-phosphate synthase

Infection control in dental health care during and after the SARS-CoV-2 outbreak

COVID-19 is an emerging infectious disease caused by the widespread transmission of the coronavirus SARS-CoV-2. Some of those infected become seriously ill. Others do not show any symptoms, but can still contribute to transmission of the virus. SARS-CoV-2 is excreted in the oral cavity and can be spread via aerosols. Aerosol generating procedures in dental health care can increase the risk of transmission of the virus. Due to the risk of infection of both dental healthcare workers and patients, additional infection control measures for all patients are strongly recommended when providing dental health care. Consideration should be given to which infection control measures are necessary when providing care in both the current situation and in the future

Including albedo in time-dependent LCA of bioenergy

Albedo change during feedstock production can substantially alter the life cycle climate impact of bioenergy. Life cycle assessment (LCA) studies have compared the effects of albedo and greenhouse gases (GHGs) based on global warming potential (GWP). However, using GWP leads to unequal weighting of climate forcers that act on different timescales. In this study, albedo was included in the time-dependent LCA, which accounts for the timing of emissions and their impacts. We employed field-measured albedo and life cycle emissions data along with time-dependent models of radiative transfer, biogenic carbon fluxes and nitrous oxide emissions from soil. Climate impacts were expressed as global mean surface temperature change over time ( increment T) and as GWP. The bioenergy system analysed was heat and power production from short-rotation willow grown on former fallow land in Sweden. We found a net cooling effect in terms of increment T per hectare (-3.8 x 10(-11) K in year 100) and GWP(100) per MJ fuel (-12.2 g CO(2)e), as a result of soil carbon sequestration via high inputs of carbon from willow roots and litter. Albedo was higher under willow than fallow, contributing to the cooling effect and accounting for 34% of GWP(100), 36% of increment T in year 50 and 6% of increment T in year 100. Albedo dominated the short-term temperature response (10-20 years) but became, in relative terms, less important over time, owing to accumulation of soil carbon under sustained production and the longer perturbation lifetime of GHGs. The timing of impacts was explicit with increment T, which improves the relevance of LCA results to climate targets. Our method can be used to quantify the first-order radiative effect of albedo change on the global climate and relate it to the climate impact of GHG emissions in LCA of bioenergy, alternative energy sources or land uses

Blood pressure variability and cardiovascular risk in the PROspective study of pravastatin in the elderly at risk (PROSPER)

Variability in blood pressure predicts cardiovascular disease in young- and middle-aged subjects, but relevant data for older individuals are sparse. We analysed data from the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) study of 5804 participants aged 70–82 years with a history of, or risk factors for cardiovascular disease. Visit-to-visit variability in blood pressure (standard deviation) was determined using a minimum of five measurements over 1 year; an inception cohort of 4819 subjects had subsequent in-trial 3 years follow-up; longer-term follow-up (mean 7.1 years) was available for 1808 subjects. Higher systolic blood pressure variability independently predicted long-term follow-up vascular and total mortality (hazard ratio per 5 mmHg increase in standard deviation of systolic blood pressure = 1.2, 95% confidence interval 1.1–1.4; hazard ratio 1.1, 95% confidence interval 1.1–1.2, respectively). Variability in diastolic blood pressure associated with increased risk for coronary events (hazard ratio 1.5, 95% confidence interval 1.2–1.8 for each 5 mmHg increase), heart failure hospitalisation (hazard ratio 1.4, 95% confidence interval 1.1–1.8) and vascular (hazard ratio 1.4, 95% confidence interval 1.1–1.7) and total mortality (hazard ratio 1.3, 95% confidence interval 1.1–1.5), all in long-term follow-up. Pulse pressure variability was associated with increased stroke risk (hazard ratio 1.2, 95% confidence interval 1.0–1.4 for each 5 mmHg increase), vascular mortality (hazard ratio 1.2, 95% confidence interval 1.0–1.3) and total mortality (hazard ratio 1.1, 95% confidence interval 1.0–1.2), all in long-term follow-up. All associations were independent of respective mean blood pressure levels, age, gender, in-trial treatment group (pravastatin or placebo) and prior vascular disease and cardiovascular disease risk factors. Our observations suggest variability in diastolic blood pressure is more strongly associated with vascular or total mortality than is systolic pressure variability in older high-risk subjects

Spreading Dynamics of Polymer Nanodroplets

The spreading of polymer droplets is studied using molecular dynamics simulations. To study the dynamics of both the precursor foot and the bulk droplet, large drops of ~200,000 monomers are simulated using a bead-spring model for polymers of chain length 10, 20, and 40 monomers per chain. We compare spreading on flat and atomistic surfaces, chain length effects, and different applications of the Langevin and dissipative particle dynamics thermostats. We find diffusive behavior for the precursor foot and good agreement with the molecular kinetic model of droplet spreading using both flat and atomistic surfaces. Despite the large system size and long simulation time relative to previous simulations, we find no evidence of hydrodynamic behavior in the spreading droplet.Comment: Physical Review E 11 pages 10 figure

Health-Related Quality of Life and Mortality in a General and Elderly Population of Patients With Type 2 Diabetes (ZODIAC-18)

OBJECTIVE- Diabetes negatively impacts the health-related quality of life (HRQOL) of patients with type 2 diabetes. An earlier analysis showed HRQOL to be associated with mortality, which suggests that measuring HRQOL could have clinical implications. We studied the association between HRQOL and total and cardiovascular mortality in patients with type 2 diabetes during long-term follow-up and specifically focused on old age and sex differences. RESEARCH DESIGN AND METHODS- HRQOL was measured in a prospectively followed cohort of 1,353 patients with type 2 diabetes using the RAND-36. Cox proportional hazard models were used to measure the independent effect of baseline HRQOL on mortality. RESULTS- During a mean follow-up of 9.6 years, 570 (42%) patients died, 280 of whom died of cardiovascular disease (49%). The Physical Component Score (PCS) and the Mental Component Score (MCS) were inversely associated with total mortality, with hazard ratios of 0.988(95% CI 0.983-0.993) and 0.990(95% CI 0.985-0.995), respectively. A 10-point-higher score on the PCS and MCS decreased the risk for total mortality by 11 and 10%, respectively. An inverse relationship with mortality was also seen for men, women, and for patients aged >75 years. Mental health was significantly related to mortality in men but not in women. CONCLUSIONS- Lower physical and mental HRQOL was associated with a higher total mortality and cardiovascular mortality in patients with type 2 diabetes; this is also the case when studying men and women and the elderly separately. The dimension mental health, related to depression and anxiety, was only associated with mortality in men, not in women