Interplay between the Dividing Cell and Its Neighbors Regulates Adherens Junction Formation during Cytokinesis in Epithelial Tissue

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Highlights? During cytokinesis, neighboring cells accumulate MyoII at the edges of the furrow ? MyoII nonautonomously sets the initial geometry of the daughter cell interface ? Neighboring membranes impede adherens junction (AJ) formation until a midbody forms ? Arp2/3-dependent actin accumulation in the dividing cell maintains AJ geometry     

Pathway of Glycine Betaine Biosynthesis in Aspergillus fumigatus

The choline oxidase (CHOA) and betaine aldehyde dehydrogenase (BADH) genes identified in Aspergillus fumigatus are present as a cluster specific for fungal genomes. Biochemical and molecular analyses of this cluster showed that it has very specific biochemical and functional features that make it unique and different from its plant and bacterial homologs. A. fumigatus ChoAp catalyzed the oxidation of choline to glycine betaine with betaine aldehyde as an intermediate and reduced molecular oxygen to hydrogen peroxide using FAD as a cofactor. A. fumigatus Badhp oxidized betaine aldehyde to glycine betaine with reduction of NAD⁺ to NADH. Analysis of the AfchoAΔ::HPH and AfbadAΔ::HPH single mutants and the AfchoAΔAfbadAΔ::HPH double mutant showed that AfChoAp is essential for the use of choline as the sole nitrogen, carbon, or carbon and nitrogen source during the germination process. AfChoAp and AfBadAp were localized in the cytosol of germinating conidia and mycelia but were absent from resting conidia. Characterization of the mutant phenotypes showed that glycine betaine in A. fumigatus functions exclusively as a metabolic intermediate in the catabolism of choline and not as a stress protectant. This study in A. fumigatus is the first molecular, cellular, and biochemical characterization of the glycine betaine biosynthetic pathway in the fungal kingdom.     

An estimate of potential threats levels to soil biodiversity in EU

Life within the soil is vital for maintaining life on Earth due to the numerous ecosystem services that it provides. However, there is evidence that pressures on the soil biota are increasing which may undermine some of these ecosystem services. Current levels of belowground biodiversity are relatively poorly known, and so no benchmark exists by which to measure possible future losses of biodiversity. Furthermore, the relative risk that each type of anthropogenic pressures places on the soil biota remains unclear. Potential threats to soil biodiversity were calculated through the use of a composite score produced from data collected from 20 international experts using the budget allocation methodology. This allowed relative weightings to be given to each of the identified pressures for which data were available in the European Soil Data Centre (ESDC). A total of seven different indicators were used for calculating the composite scores. These data were applied through a model using ArcGIS to produce a spatial analysis of composite pressures on soil biodiversity at the European scale. The model highlights the variation in the composite result of the potential threats to soil biodiversity. A sensitivity analysis demonstrated that the intensity of land exploitation, both in terms of agriculture and use intensity, as well as in terms of land‐use dynamics, were the main factors applying pressure on soil biodiversity. It is important to note that the model should not be viewed as an estimate of the current level of soil biodiversity in Europe, but as an estimate of pressures that are currently being exerted. The results obtained should be seen as a starting point for further investigation on this relatively unknown issue and demonstrate the utility of this type of model which may be applied to other regions and scales.     

Characterization of oxidative stress in blood from diabetic vs. hypercholesterolaemic patients,using a novel synthesized marker

In the present study, we extend our novel concept of designing and using exogenous markers for the characterization of oxidative stress (OS) and OS-associated diseases. The aim was to use such a synthetic compound as a tool for studying OS in blood from diabetic and hypercholesterolaemic (Hc) patients. The marker used N-linoleoyl tyrosine (LT) was constructed from tyrosine and linoleic acid (LA); both components are known to be easily oxidized upon exposure to different types of reactive oxygen/nitrogen species (ROS/RNS), and to generate specific oxidized products, depending on the type of oxidants present in vivo. Using the LT probe, we showed that the ratios of oxidized LT to total LT (Ox-LT/LT) is significantly higher in blood samples obtained from diabetic patients, than in Hc patients or healthy control subjects. LC/MS analysis revealed that blood from diabetic patients oxidizes the marker with predominant formation of Ox-LT hydroperoxide (LT-OOH) and epoxide (epoxy-LT), where the LA moiety is oxidized to hydroperoxide and to epoxide, respectively. Analysis of oxysterol levels in these samples (GC/MS) revealed that the blood of both diabetic and Hc patients contained significantly more oxysterols than blood of control subjects. Consumption of pomegranate juice by diabetic patients for 3 months suppressed their blood capacity to oxidize the LT and similarly also reduced their blood oxysterol/total cholesterol ratio by 93%. The use of an exogenous marker to characterize OS in blood samples yields important information on the extent of OS, and can provide a fingerprint for the early identification of different pathological conditions associated with OS.     

Sphingosine-1-phosphate: A Janus-faced mediator of fibrotic diseases

Sphingosine-1-phosphate (S1P) is a pleiotropic lipid mediator that acts either on G protein-coupled S1P receptors on the cell surface or via intracellular target sites. In addition to the well established effects of S1P in angiogenesis, carcinogenesis and immunity, evidence is now continuously accumulating which demonstrates that S1P is an important regulator of fibrosis. The contribution of S1P to fibrosis is of a Janus-faced nature as S1P exhibits both pro- and anti-fibrotic effects depending on its site of action. Extracellular S1P promotes fibrotic processes in a S1P receptor-dependent manner, whereas intracellular S1P has an opposite effect and dampens a fibrotic reaction by yet unidentified mechanisms. Fibrosis is a result of chronic irritation by various factors and is defined by an excess production of extracellular matrix leading to tissue scarring and organ dysfunction. In this review, we highlight the general effects of extracellular and intracellular S1P on the multistep cascade of pathological fibrogenesis including tissue injury, inflammation and the action of pro-fibrotic cytokines that stimulate ECM production and deposition. In a second part we summarize the current knowledge about the involvement of S1P signaling in the development of organ fibrosis of the lung, kidney, liver, heart and skin. Altogether, it is becoming clear that targeting the sphingosine kinase-1/S1P signaling pathway offers therapeutic potential in the treatment of various fibrotic processes. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.     

Inhibition of cholesteryl ester transfer protein by anacetrapib does not impair the anti-inflammatory properties of high density lipoprotein

Cholesteryl ester transfer protein (CETP) is a target of therapeutic intervention for coronary heart disease. Anacetrapib, a potent inhibitor of CETP, has been shown to reduce LDL-cholesterol by 40% and increase HDL-cholesterol by 140% in patients, and is currently being evaluated in a phase III cardiovascular outcomes trial. HDL is known to possess anti-inflammatory properties, however with such large increases in HDL-cholesterol, it is unclear whether CETP inhibition perturbs HDL functionality such as anti-inflammatory effects on endothelial cells. The purpose of the present study was to determine whether CETP inhibition by anacetrapib affects the anti-inflammatory properties of HDL. HDL was isolated from either hamsters treated with vehicle or anacetrapib for 2 weeks, or from normal human subjects treated either placebo, 20 mg, or 150 mg anacetrapib daily for 2 weeks. Anacetrapib treatment increased plasma HDL cholesterol levels by 65% and between 48 and 82% in hamsters and humans, respectively. Pre-incubation of human aortic endothelial cells with HDL isolated from both control and anacetrapib treated hamsters suppressed TNFα induced expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin. Similar results were obtained with human HDL samples pre and post treatment with placebo or anacetrapib. Further, HDL inhibited TNFα-induced MCP-1 secretion, monocyte adhesion and NF-κB activation in endothelial cells, and the inhibition was similar between control and anacetrapib treated groups. These studies demonstrate that anacetrapib treatment does not impair the ability of HDL to suppress an inflammatory response in endothelial cells.     

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