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341.
Arjen?MeijerEmail author Mark?HuijbregtsEmail author Lucas?Reijnders 《The International Journal of Life Cycle Assessment》2005,10(6):383-392
- Part 1: Characterisation factors (DOI: http://dx.doi.org/10.1065/lca2004.12.194.1)
Part 2: Damage scores (DOI: http://dx.doi.org/10.1065/lca2004.12.194.2)
- Preamble. In this series of two papers, a methodology to calculate damages to human health caused by indoor emissions from
building materials is presented and applied. Part 1 presents the theoretical foundation of the indoor emission methodology
developed, as well as characterisation factors calculated for 36 organic compounds, radon and gamma radiation. Part 2 calculates
damage scores of building materials with the characterisation factors presented in part 1. The relevancy of including indoor
air emission in the full damage scores at a material level and a dwelling level is also quantified and discussed.
Goal, Scope and Background In industrialized countries such as the Netherlands, the concentration of pollutants originating from building materials
in the indoor environment has shown an increasing trend during the last decades due to improved isolation and decreased ventilation
of dwellings. These pollutants may give rise to negative impacts on human health, ranging from irritation to tumours. However,
such negative impacts on health are not included in current life cycle assessments of dwellings. In this study, damages to
the health of occupants caused by a number of organic compounds and by radioactivity emitted by building materials, including
those due to indoor exposure, have been calculated for a number of categories of common building materials. The total damage
to human health due to emissions occurring in the use phase of the Dutch reference dwelling is compared with the total damage
to human health associated with the rest of the life cycle of the same dwelling.
Methods Human health damage scores per kilogram of building material for compartments of the Dutch reference dwelling have been calculated
using the methodology described in part I of this research. This methodology includes the calculation of the fate, effect
and damage factors, based on disability adjusted life years (DALYs), and has been applied assuming average concentrations
of pollutants in building materials. Damage scores for health impacts of exposure to pollutants emitted during the production
and the disposal phase of the same building materials were calculated using standard LCIA methodology.
Results and Discussion Human health damage scores due to emissions of pollutants occurring in the use phase of building materials applied at the
first or second floor are up to 20 times lower or higher than the corresponding damage scores associated with the rest of
the life cycle of the same building materials. The damage scores due to emissions occurring in the use phase of building materials
applied in the crawlspace are up to 105 times lower than those of building materials applied in the other compartments. The
total damage to human health due to emissions occurring in the use phase of the Dutch reference dwelling has the same order
of magnitude as the total damage to human health associated with the rest of the life cycle of the same dwelling. At a dwelling
level, radon and gamma radiation are dominant in the human health damage score among the pollutants studied.
Conclusion Health damages due to indoor exposure to contaminants emitted by building materials cannot be neglected for several materials
when compared with damage scores associated with the rest of the life cycle of the same building materials. Indoor exposure
to pollutants emitted by building materials should be included in the life cycle assessment of dwellings in order to make
the assessment better reflect full impact of the life cycle. 相似文献
342.
A novel approach for nontargeted data analysis for metabolomics. Large-scale profiling of tomato fruit volatiles 总被引:15,自引:0,他引:15
Tikunov Y Lommen A de Vos CH Verhoeven HA Bino RJ Hall RD Bovy AG 《Plant physiology》2005,139(3):1125-1137
To take full advantage of the power of functional genomics technologies and in particular those for metabolomics, both the analytical approach and the strategy chosen for data analysis need to be as unbiased and comprehensive as possible. Existing approaches to analyze metabolomic data still do not allow a fast and unbiased comparative analysis of the metabolic composition of the hundreds of genotypes that are often the target of modern investigations. We have now developed a novel strategy to analyze such metabolomic data. This approach consists of (1) full mass spectral alignment of gas chromatography (GC)-mass spectrometry (MS) metabolic profiles using the MetAlign software package, (2) followed by multivariate comparative analysis of metabolic phenotypes at the level of individual molecular fragments, and (3) multivariate mass spectral reconstruction, a method allowing metabolite discrimination, recognition, and identification. This approach has allowed a fast and unbiased comparative multivariate analysis of the volatile metabolite composition of ripe fruits of 94 tomato (Lycopersicon esculentum Mill.) genotypes, based on intensity patterns of >20,000 individual molecular fragments throughout 198 GC-MS datasets. Variation in metabolite composition, both between- and within-fruit types, was found and the discriminative metabolites were revealed. In the entire genotype set, a total of 322 different compounds could be distinguished using multivariate mass spectral reconstruction. A hierarchical cluster analysis of these metabolites resulted in clustering of structurally related metabolites derived from the same biochemical precursors. The approach chosen will further enhance the comprehensiveness of GC-MS-based metabolomics approaches and will therefore prove a useful addition to nontargeted functional genomics research. 相似文献
343.
Bakker H Routier F Oelmann S Jordi W Lommen A Gerardy-Schahn R Bosch D 《Glycobiology》2005,15(2):193-201
Nucleotide-sugar transporters (NSTs) form a family of structurally related transmembrane proteins that transport nucleotide-sugars from the cytoplasm to the endoplasmic reticulum and Golgi lumen. In these organelles, activated sugars are substrates for various glycosyltransferases involved in oligo- and polysaccharide biosynthesis. The Arabidopsis thaliana genome contains more than 40 members of this transporter gene family, of which only a few are functionally characterized. In this study, two Arabidopsis UDP-galactose transporter cDNAs (UDP-GalT1 and UDP-GalT2) are isolated by expression cloning using a Chinese hamster ovary cell line (CHO-Lec8) deficient in UDP-galactose transport. The isolated genes show only 21% identity to each other and very limited sequence identity with human and yeast UDP-galactose transporters and other NSTs. Despite this low overall identity, the two proteins clearly belong to the same gene family. Besides complementing Lec8 cells, the two NSTs are shown to transport exclusively UDP-galactose by an in vitro NST assay. The most homologous proteins with known function are plant transporters that locate in the inner chloroplast membrane and transport triose-phosphate, phosphoenolpyruvate, glucose-6-phosphate, and xylulose 5-phosphate. Also, the latter proteins are members of the same family, which therefore has been named the NST/triose-phosphate transporter family. 相似文献
344.
345.
Identification and characterization of two novel clostridial bacteriocins,circularin A and closticin 574 总被引:1,自引:0,他引:1
Kemperman R Kuipers A Karsens H Nauta A Kuipers O Kok J 《Applied and environmental microbiology》2003,69(3):1589-1597
Two novel antibacterial peptides of clostridial species were purified, N-terminally sequenced, and characterized. Moreover, their structural genes were identified. Closticin 574 is an 82-amino-acid bacteriocin produced by Clostridium tyrobutyricum ADRIAT 932. The supernatant of the producing strain showed a high level of activity against the indicator strain C. tyrobutyricum. The protein is synthesized as a preproprotein that is possibly secreted via the general secretion pathway, after which it is hydrolyzed at an Asp-Pro site. Circularin A is produced by Clostridium beijerinckii ATCC 25752 as a prepeptide of 72 amino acids. Cleavage of the prepeptide between the third leucine and fourth valine residues followed by a head-to-tail ligation between the N and C termini creates a circular antimicrobial peptide of 69 amino acids. The unusually small circularin A leader peptide of three amino acids is cleaved off in this process. The supernatant of C. beijerinckii ATCC 25752 showed a broad antibacterial activity range. 相似文献
346.
Contribution of aerial hyphae of Aspergillus oryzae to respiration in a model solid-state fermentation system 总被引:1,自引:0,他引:1
Rahardjo YS Weber FJ le Comte EP Tramper J Rinzema A 《Biotechnology and bioengineering》2002,78(5):539-544
Oxygen transfer is for two reasons a major concern in scale-up and process control in industrial application of aerobic fungal solid-state fermentation (SSF): 1) heat production is proportional to oxygen uptake and it is well known that heat removal is one of the main problems in scaled-up fermenters, and 2) oxygen supply to the mycelium on the surface of or inside the substrate particles may be hampered by diffusion limitation. This article gives the first experimental evidence that aerial hyphae are important for fungal respiration in SSF. In cultures of A. oryzae on a wheat-flour model substrate, aerial hyphae contributed up to 75% of the oxygen uptake rate by the fungus. This is due to the fact that A. oryzae forms very abundant aerial mycelium and diffusion of oxygen in the gas-filled pores of the aerial hyphae layer is rapid. It means that diffusion limitation in the densely packed mycelium layer that is formed closer to the substrate surface and that has liquid-filled pores is much less important for A. oryzae than was previously reported for R. oligosporus and C. minitans. It also means that the overall oxygen uptake rate for A. oryzae is much higher than the oxygen uptake rate that can be predicted in the densely packed mycelium layer for R. oligosporus and C. minitans. This would imply that cooling problems become more pronounced. Therefore, it is very important to clarify the physiological role of aerial hyphae in SSF. 相似文献
347.
Elzinga BM Havinga R Baller JF Wolters H Bloks V Mensenkamp AR Kuipers F Verkade HJ 《Biochimica et biophysica acta》2002,1573(1):9-20
Bile salts (BS) have been shown to suppress the secretion of very-low-density lipoprotein-triglyceride (VLDL-TG) in rat and human hepatocytes in vitro. In the present study, we investigated whether the transhepatic BS flux affects VLDL-TG concentration and hepatic VLDL-TG secretion in vivo. In rats, the transhepatic BS flux was quantitatively manipulated by 1-week chronic bile diversion (BD), followed by intraduodenal infusion with taurocholate (TC) or saline for 6 h. In mice, the transhepatic BS flux was manipulated by a 3-week dietary supplementation with TC (0.5 wt.%) or cholestyramine (2 wt.%). In rats, BD followed by saline or TC infusion did not affect plasma triacylglycerol (TG) concentration, hepatic TG production rate or VLDL lipid composition, compared to control rats. In mice supplemented for 3 weeks with TC or cholestyramine, the transhepatic BS flux was increased by 335% and decreased by 48%, respectively, compared to controls. Among the three experimental groups of mice, an inverse relationship between transhepatic BS flux and either plasma TG concentration (R(2)=0.89) or VLDL-TG production rate (R(2)=0.87) was observed, but differences were relatively small. Present data support the concept that BS can reduce VLDL-TG concentration and inhibit hepatic TG secretion in vivo; however, this occurs only at supraphysiological transhepatic BS fluxes in mice. 相似文献
348.
Regulation of floral scent production in petunia revealed by targeted metabolomics 总被引:15,自引:0,他引:15
Verdonk JC Ric de Vos CH Verhoeven HA Haring MA van Tunen AJ Schuurink RC 《Phytochemistry》2003,62(6):997-1008
349.
A tomato metacaspase gene is upregulated during programmed cell death in<Emphasis Type="Italic"> Botrytis cinerea</Emphasis>-infected leaves 总被引:5,自引:0,他引:5
Programmed cell death (PCD) in plant cells is often accompanied by biochemical and morphological hallmarks similar to those of animal apoptosis. However, orthologs of animal caspases, cysteinyl aspartate-specific proteases that constitute the core component of animal apoptosis, have not yet been identified in plants. Recent studies have revealed the presence of a family of genes encoding proteins with distant homology to mammalian caspases, designated metacaspases, in the Arabidopsis thaliana genome. Here, we describe the isolation of LeMCA1, a type-II metacaspase cDNA clone from tomato (Lycopersicon esculentum Mill.). BLAST analysis demonstrated that the LeMCA1 gene is located in close vicinity of several genes that have been linked with PCD. Southern analysis indicated the existence of at least one more metacaspase in the tomato genome. LeMCA1 mRNA levels rapidly increased upon infection of tomato leaves with Botrytis cinerea, a fungal pathogen that induces cell death in several plant species. LeMCA1 was not upregulated during chemical-induced PCD in suspension-cultured tomato cells. 相似文献
350.
Elzinga BM Baller JF Mensenkamp AR Yao Z Agellon LB Kuipers F Verkade HJ 《Biochimica et biophysica acta》2003,1635(2-3):93-103
Bile salts (BS) inhibit the secretion of apolipoprotein B (apoB) and triacylglycerol (TG) in primary rat, mouse and human hepatocytes and in mice in vivo. We investigated whether lipidation of apoB into a lipoprotein particle is required for this inhibitory action of BS. The sodium/taurocholate co-transporting polypeptide (Ntcp) was co-expressed in McArdle-RH7777 (McA-RH7777) cells stably expressing the full-length human apoB100 (h-apoB100, secreted as TG-rich lipoprotein particles) or carboxyl-truncated human apoB18 (h-apoB18, secreted in lipid-free form). The doubly transfected cell lines (h-apoB/r-Ntcp) effectively accumulated taurocholic acid (TC). TC incubation decreased the secretion of endogenous rat apoB100 (-50%) and h-apoB18 (-35%), but did not affect secretion of rat apoA-I. Pulse-chase experiments (35S-methionine) indicated that the impaired secretion of radiolabeled h-apoB18 and h-apoB100 was associated with accelerated intracellular degradation. The calpain protease inhibitor N-acetyl-leucyl-leucyl-norleucinal (ALLN) partially inhibited intracellular apoB degradation but did not affect the amount of either h-apoB18 or h-apoB100 secreted into the medium, indicating that inhibition of apoB secretion by TC is not due to calpain-dependent proteasomal degradation. We conclude that TC does not inhibit apoB secretion by interference with its lipidation, but rather involves a mechanism dependent on the N-terminal end of apoB. 相似文献