Environmental life cycle assessment of linoleum

Linoleum is a floor covering consisting mainly of linseed oil, other vegetable oils, wood flour and limestone on a carrier of jute. Forbo-Krommenie B.V. commissioned the Centre of Environmental Science (CML) to carry out an Environmental Life Cycle Assessment for linoleum floors. The goal of this study was to assess the environmental performance of linoleum floors, indicating possible options for improvement, and assessing the sensitivity of the results to methodological choices. The functional unit was defined as: 2000 m² linoleum produced in 1998, used in an office or public building over a period of 20 years. The method followed in this study is based on a nearly final draft version of the LCA guide published by CML in corporation with many others, which is an update of the guide on LCA of 1992. From the contribution analysis, the main contributing processes became clear. In addition, the sensitivity analysis by scenarios showed that the type of maintenance during use and the pigments used can have a large influence on the results. Major data gaps of the study were capital goods and unknown chemicals. Sensitivity analysis also showed that these gaps can lead to an underestimation. Based on this study, some options to improve the environmental performance of linoleum were formulated and advice for further LCA studies on linoleum was given.     

Opposite Contributions of Trunk and Leg Fat Mass with Plasma Lipase Activities: The Hoorn Study

Objective: Lipoprotein lipase (LPL) and hepatic lipase (HL) are essential in hydrolysis of triglyceride‐rich lipoproteins. LPL activity is negatively, whereas HL activity is positively, associated with total body fat. We determined the associations of trunk and leg fat mass with plasma LPL and HL activities in a cross‐sectional study. Research Methods and Procedures: LPL and HL activities were determined in post‐heparin plasma in a sample of 197 men and 209 women, 60 to 87 years of age. A total body DXA scan was performed to determine trunk and leg fat mass. Results: In women, but not in men, trunk fat mass was negatively associated with LPL activity, whereas leg fat mass was positively associated, after mutual adjustment and adjustment for age. Standardized βs (95% confidence interval) for trunk and leg fat mass were ?0.24 (?0.41; ?0.08) and 0.14 (?0.02; 0.31), respectively (interaction by sex, p = 0.03). Larger trunk fat mass was associated with higher HL activity in men [0.48 (0.28; 0.68)] and women [0.40 (0.24; 0.56)]. A negative association of leg fat mass and HL activity was observed in men, although not statistically significant [?0.13 (?0.33; 0.06)], and in women [?0.28 (?0.38; ?0.18)]. Discussion: Abdominal fat is associated with unfavorable and femoral fat with favorable LPL and HL activities in plasma.     

Hyperthermophilic redox chemistry: a re-evaluation

The redox chemistry of Pyrococcus furiosus rubredoxin and ferredoxin has been studied as a function of temperature in direct voltammetry and in EPR monitored bulk titrations. The E_ms of both proteins, measured with direct voltammetry, have a normal (linear) temperature dependence and show no pH dependence. EPR monitoring is not a reliable method to determine the temperature dependence of the E_m: upon rapid freezing the proteins take their conformation corresponding to the freezing point of the solution.     

Bronchoconstriction Induces TGF-β Release and Airway Remodelling in Guinea Pig Lung Slices

Airway remodelling, including smooth muscle remodelling, is a primary cause of airflow limitation in asthma. Recent evidence links bronchoconstriction to airway remodelling in asthma. The mechanisms involved are poorly understood. A possible player is the multifunctional cytokine TGF-β, which plays an important role in airway remodelling. Guinea pig lung slices were used as an in vitro model to investigate mechanisms involved in bronchoconstriction-induced airway remodelling. To address this aim, mechanical effects of bronchoconstricting stimuli on contractile protein expression and TGF-β release were investigated. Lung slices were viable for at least 48 h. Both methacholine and TGF-β₁ augmented the expression of contractile proteins (sm-α-actin, sm-myosin, calponin) after 48 h. Confocal fluorescence microscopy showed that increased sm-myosin expression was enhanced in the peripheral airways and the central airways. Mechanistic studies demonstrated that methacholine-induced bronchoconstriction mediated the release of biologically active TGF-β, which caused the increased contractile protein expression, as inhibition of actin polymerization (latrunculin A) or TGF-β receptor kinase (SB431542) prevented the methacholine effects, whereas other bronchoconstricting agents (histamine and KCl) mimicked the effects of methacholine. Collectively, bronchoconstriction promotes the release of TGF-β, which induces airway smooth muscle remodelling. This study shows that lung slices are a useful in vitro model to study mechanisms involved in airway remodelling.     

Life cycle inventory modeling of phosphorus substitution,losses and crop uptake after land application of organic waste products

Purpose

Life cycle assessments (LCAs) that attempt to provide advice on treatment options for phosphorus (P) containing organic waste products encounter problems related to the quantification of mineral P fertilizer substitution, P loss and crop P uptake after land application. The purpose of this study was to develop a relatively easy to use life cycle inventory model, known as PLCI, that could be used to estimate these values.

Methods

A life cycle inventory model for P was developed, which estimates the effect of an application of organic waste followed by ordinary fertilizer management in the modeling period. This was compared with a simulation without the initial waste application. The difference in mineral P fertilizer application (substitution), P loss and crop P uptake was then calculated and expressed as a proportion of the amount of waste applied. As an example, the effect of an initial application of mineral fertilizer, sewage sludge and ash on two farm types was simulated. These results were applied in an LCA case study of different sewage sludge treatment options.

Results and discussion

Farm type influenced the P fertilizer substitution, loss and crop uptake factors. The application on an arable farm showed a substitution of 28 to 31%, relatively low P loss and a large spread in crop P uptake for the different P sources, compared with the pig farm. Application on a pig farm showed no mineral P substitution. For substitution, mineral fertilizer outperformed waste product fertilizer with a short modeling period, due to higher immediate P availability, which was not the case with a long period. The LCA case study showed that the P substitution factor had an influence on the environmental impact categories climate change and depletion of reserve-based abiotic resources while the P loss factor influenced freshwater eutrophication. Application of the P loss and substitution factors generated from the PLCI model resulted in higher environmental burdens and lower savings than using conventional factors.

Conclusions

The soil P status mainly affected P substitution and loss, with the fertilizer type only having a small influence when soils had a low P status. The PLCI model can facilitate more coherent and rigorous estimates of P substitution and loss to be used in LCA studies involving application of waste products on agricultural land. This is important since P substitution and loss can have an important influence on impact categories, such as freshwater eutrophication and resource depletion.

     

Functional CD169 on Macrophages Mediates Interaction with Dendritic Cells for CD8+ T Cell Cross-Priming

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What to do with HLA-DO?

Antigenic peptide binding to MHC class II molecules in the endocytic pathway occurs via a multifactorial process that requires the support of a specialized lysosomal chaperone called HLA-DM. DM shows both in primary amino acid sequence and quaternary structure a high homology to both MHC class I and class II molecules. Like the peptide presenting class II molecules, DM is expressed in all professional antigen presenting cells. DM catalyzes the dissociation of peptides that do not bind stably to the class II peptide-binding groove, thereby leading to the preferential presentation of stably binding antigenic peptides. The recently discovered HLA-DO molecule is mainly expressed in B cells and associates with DM, thereby markedly affecting DM function. Like DM, the genes encoding the HLA-DO heterodimer lie within the MHC class II region and exhibit strong homology to classical class II molecules. This review evaluates the unique effects of DO on DM-mediated antigen presentation by MHC class II molecules and discusses the possible physiological relevance for the B cell-specific expression of DO and its function.     

Scavenger receptor BI and ATP-binding cassette transporter A1 in reverse cholesterol transport and atherosclerosis

PURPOSE OF REVIEW: The appearance of scavenger receptor class B type I (SR-BI) and ATP-binding cassette transporter A1 (ABCA1) in macrophages and liver implicates these transporters in different stages of reverse cholesterol transport. This review focuses on the role of SR-BI and ABCA1 in reverse cholesterol transport in the context of atherosclerotic lesion development. RECENT FINDINGS: Recent studies indicate that hepatic expression of ABCA1 and SR-BI is important for the generation of nascent HDL and the delivery of HDL cholesteryl esters to the liver, respectively. Although macrophage SR-BI and ABCA1 do not contribute significantly to circulating HDL levels, the perpetual cycle of HDL lipidation and delipidation by the liver ensures the availability of acceptors for cholesterol efflux that maintain cholesterol homeostasis in arterial macrophages, thereby reducing atherogenesis. In addition to its established role in the selective uptake of HDL cholesteryl esters, there is now evidence that hepatic SR-BI facilitates postprandial lipid metabolism, and that hepatic secretion of VLDL is dependent on ABCA1-mediated nascent HDL formation. Thus, remnant and HDL metabolism are more intimately intertwined in hepatic lipid metabolism than has previously been appreciated. SUMMARY: Recent advances in the understanding of the role of ABCA1 and SR-BI in HDL metabolism and their atheroprotective properties indicate the significant potential of modulating ABCA1 and SR-BI expression in both arterial wall macrophages and the liver for the treatment of atherosclerotic coronary artery disease.