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91.
Warsen Jens Bauer Christian Schebek Liselotte 《The International Journal of Life Cycle Assessment》2009,14(1):52-63
Background, aim and scope Renewable energy sources nowadays constitute an increasingly important issue in our society, basically because of the need
for alternative sources of energy to fossil fuels that are free of CO2 emissions and pollution and also because of other problems such as the diminution of the reserves of these fossil fuels,
their increasing prices and the economic dependence of non-producers countries on those that produce fossil fuels. One of
the renewable energy sources that has experienced a bigger growth over the last years is wind power, with the introduction
of new wind farms all over the world and the new advances in wind power technology. Wind power produces electrical energy
from the kinetic energy of the wind without producing any pollution or emissions during the conversion process. Although wind
power does not produce pollution or emissions during operation, it should be considered that there is an environmental impact
due to the manufacturing process of the wind turbine and the disposal process at the end of the wind turbine life cycle, and
this environmental impact should be quantified in order to compare the effects of the production of energy and to analyse
the possibilities of improvement of the process from that point of view. Thus, the aim of this study is to analyse the environmental
impact of wind energy technology, considering the whole life cycle of the wind power system, by means of the application of
the ISO 14040 standard [ISO (1998) ISO 14040. Environmental management—life cycle assessment—principles and framework. International Standard Organization,
Geneva, Switzerland], which allows quantification of the overall impact of a wind turbine and each of its component parts
using a Life Cycle Assessment (LCA) study.
Materials and methods The procedures, details, and results obtained are based on the application of the existing international standards of LCA.
In addition, environmental details and indications of materials and energy consumption provided by the various companies related
to the production of the component parts are certified by the application of the environmental management system ISO 14001
[ISO (2004) ISO 14001 Environmental management systems—requirements with guidance for use. International Standard Organization, Geneva,
Switzerland]. A wind turbine is analysed during all the phases of its life cycle, from cradle to grave, by applying this methodology,
taking into account all the processes related to the wind turbine: the production of its main components (through the incorporation
of cut-off criteria), the transport to the wind farm, the subsequent installation, the start-up, the maintenance and the final
dismantling and stripping down into waste materials and their treatment. The study has been developed in accordance with the
ISO 14044 standard [ISO (2006) ISO 14044: Environmental management—life cycle assessment—requirements and guidelines. International Standard Organization,
Geneva, Switzerland] currently in force.
Results The application of LCA, according to the corresponding international standards, has made it possible to determine and quantify
the environmental impact associated with a wind turbine. On the basis of this data, the final environmental effect of the
wind turbine after a lifespan of 20 years and its subsequent decommissioning have been studied. The environmental advantages
of the generation of electricity using wind energy, that is, the reduction in emissions and contamination due to the use of
a clean energy source, have also been evaluated.
Discussion This study concludes that the environmental pollution resulting from all the phases of the wind turbine (manufacture, start-up,
use, and dismantling) during the whole of its lifetime is recovered in less than 1 year.
Conclusions From the developed LCA model, the important levels of contamination of certain materials can be obtained, for instance, the
prepreg (a composite made by a mixture of epoxy resin and fibreglass). Furthermore, it has been concluded that it is possible
to reduce the environmental effects of manufacturing and recycling processes of wind turbines and their components.
Recommendations and perspectives In order to achieve this goal in a fast and effective way, it is essential to enlist the cooperation of the different manufacturers. 相似文献
92.
Manuela Mancini Nevena Veljkovic Valentina Corradi Elisa Zuffa Patrizia Corrado Eleonora Pagnotta Giovanni Martinelli Enza Barbieri Maria Alessandra Santucci 《Traffic (Copenhagen, Denmark)》2009,10(6):637-647
Here we demonstrated that the ‘loss of function’ of not‐rearranged c‐ABL in chronic myeloid leukemia (CML) is promoted by its cytoplasmic compartmentalization bound to 14‐3‐3 sigma scaffolding protein. In particular, constitutive tyrosine kinase (TK) activity of p210 BCR‐ABL blocks c‐Jun N‐terminal kinase (JNK) phosphorylation leading to 14‐3‐3 sigma phosphorylation at a critical residue (Ser186) for c‐ABL binding in response to DNA damage. Moreover, it is associated with 14‐3‐3 sigma over‐expression arising from epigenetic mechanisms (promoter hyper‐acetylation). Accordingly, p210 BCR‐ABL TK inhibition by the TK inhibitor Imatinib mesylate (IM) evokes multiple events, including JNK phosphorylation at Thr183, p38 mitogen‐activated protein kinase (MAPK) phosphorylation at Thr180, c‐ABL de‐phosphorylation at Ser residues involved in 14‐3‐3 binding and reduction of 14‐3‐3 sigma expression, that let c‐ABL release from 14‐3‐3 sigma and nuclear import, and address BCR‐ABL‐expressing cells towards apoptotic death. Informational spectrum method (ISM), a virtual spectroscopy method for analysis of protein interactions based on their structure, and mathematical filtering in cross spectrum (CS) analysis identified 14‐3‐3 sigma/c‐ABL binding sites. Further investigation on CS profiles of c‐ABL‐ and p210 BCR‐ABL‐containing complexes revealed the mechanism likely involved 14‐3‐3 precluded phosphorylation in CML cells. 相似文献
93.
Identification of a new HLA-A*0201-restricted cytotoxic T lymphocyte epitope from CML28 总被引:1,自引:0,他引:1
Han JF Zhao TT Liu HL Lin ZH Wang HM Ruan ZH Zou LY Wu YZ 《Cancer immunology, immunotherapy : CII》2006,55(12):1575-1583
Identification of cytotoxic T lymphocyte (CTL) epitopes from additional tumor antigens is essential for the development of specific immunotherapy of malignant tumors. CML28, a recently discovered cancer-testis (CT) antigen from chronic myelogenous leukemia, is considered to be a promising target of tumor-specific immunotherapy. Because HLA-A*0201 is one of the most common histocompatibility molecule in Chinese, we aim at identifying CML28 peptides presented by HLA-A*0201. A panel of CML28-derived antigenic peptides was predicted using a computer-based program. Four peptides with highest predicted score were synthesized and tested for their binding affinities to HLA-A*0201 molecule. Then these peptides were assessed for their immunogenicity to elicit specific immune responses mediated by CTLs both in vitro, from PBMCs sourced from four healthy HLA-A*0201+ donors, and in vivo, in HLA-A*0201 transgenic mice. One of the tested peptides, CML28(173–181), induced peptide-specific CTLs in vitro as well as in vivo, which could specifically secrete IFN-γ and lyse major histocompatibility complex (MHC)-matched tumor cell lines endogenously expressing CML28 antigen and CML28(173–181) pulsed Jurkat-A2/Kb cells, respectively. These results demonstrate that CML28(173–181) is a naturally processed and presented CTL epitope with HLA-A*0201 motif and has a promising immunogenicity both in vitro and in vivo. As CML28 is expressed in a large variety of histological tumors besides chronic myelogenous leukemia, we propose that the newly identified epitope, CML28(173–181), would be of potential use in peptide-based, cancer-specific immunotherapy against a broad spectrum of tumors. 相似文献
94.
95.
Kei-ichi Ozaki Nobuyuki Baba Toshiaki Sakamoto Susumu Tanimura 《Biochemical and biophysical research communications》2010,391(4):1610-1615
Deregulated activation of protein tyrosine kinases, such as the epidermal growth factor receptor (EGFR) and Abl, is associated with human cancers including non-small cell lung cancer (NSCLC) and chronic myeloid leukemia (CML). Although inhibitors of such activated kinases have proved to be of therapeutic benefit in individuals with NSCLC or CML, some patients manifest intrinsic or acquired resistance to these drugs. We now show that, whereas blockade of either the extracellular signal-regulated kinase (ERK) pathway or the phosphatidylinositol 3-kinase (PI3K)-Akt pathway alone induced only a low level of cell death, it markedly sensitized NSCLC or CML cells to the induction of apoptosis by histone deacetylase (HDAC) inhibitors. Such enhanced cell death induced by the respective drug combinations was apparent even in NSCLC or CML cells exhibiting resistance to EGFR or Abl tyrosine kinase inhibitors, respectively. Co-administration of a cytostatic signaling pathway inhibitor may contribute to the development of safer anticancer strategies by lowering the required dose of cytotoxic HDAC inhibitors for a variety of cancers. 相似文献
96.
Recent studies have shown that trans-phosphorylation of the Abl SH3 domain at Tyr89 by Src-family kinases is required for the full transforming activity of Bcr-Abl. Tyr89 localizes to a binding surface of the SH3 domain that engages the SH2-kinase linker in the crystal structure of the c-Abl core. Displacement of SH3 from the linker is likely to influence efficient downregulation of c-Abl. Hydrogen-deuterium exchange (HX) and mass spectrometry (MS) were used to investigate whether Tyr89 phosphorylation affects the ability of the SH3 domain to interact intramolecularly with the SH2-kinase linker in cis as well as other peptide ligands in trans. HX MS analysis of SH3 binding showed that when various Abl constructs were phosphorylated at Tyr89 by the Src-family kinase Hck, SH3 was unable to engage a high-affinity ligand in trans and that interaction with the linker in cis was reduced dramatically in a construct containing the SH3 and SH2 domains plus the linker. Phosphorylation of the Abl SH3 domain on Tyr89 also interfered with binding to the negative regulatory protein Abi-1 in trans. Site-directed mutagenesis of Tyr89 and Tyr245, another tyrosine phosphorylation site located in the linker that may also influence SH3 binding, implicated Tyr89 as the key residue necessary for disrupting regulation after phosphorylation. These results imply that phosphorylation at Tyr89 by Src-family kinases prevents engagement of the Abl SH3 domain with its intramolecular binding partner leading to enhanced Abl kinase activity and cellular signaling. 相似文献
97.
98.
Miyahara Y Ikeda S Muroya T Yasuoka C Urata Y Horiuchi S Kohno S Kondo T 《Biochemical and biophysical research communications》2002,296(1):32-40
Advanced glycation end products (AGEs) play an important role in the development of angiopathy in diabetes mellitus and atherosclerosis. Here, we show that adducts of N(epsilon)-(carboxymethyl)lysine (CML), a major AGE, and bovine serum albumin (CML-BSA) stimulated gamma-glutamylcysteine synthetase (gamma-GCS), which is a key enzyme of glutathione (GSH) synthesis, in RAW264.7 mouse macrophage-like cells. CML-BSA stimulated the expression of gamma-GCS heavy subunit (h) time- and dose-dependently and concomitantly increased GSH levels. CML-BSA also stimulated DNA-binding activity of activator protein-1 (AP-1) within 3h, but the stimulatory effect decreased in 5h, and nuclear factor-kappaB (NF-kappaB) with a peak activity at 1h and the stimulatory effect diminished in 3h. Studies of luciferase activity of the gamma-GCSh promoter showed that deletion and mutagenesis of the AP-1-site abolished CML-BSA-induced up-regulation, while that of NF-kappaB-site did not affect CML-BSA-induced activity. CML-BSA also stimulated the activity of protein kinase C, Ras/Raf-1, and MEK/ERK1/2. Inhibition of ERK1/2 abolished CML-BSA-stimulated AP-1 DNA-binding activity and gamma-GCSh mRNA expression. Our results suggest that induction of gamma-GCS by CML adducts seems to increase the defense potential of cells against oxidative stress produced during glycation processes. 相似文献
99.
J R Honeycombe 《Mutation research》1978,57(1):35-49
In vitro exposure of human lymphocytes to busulphan (BUS) produced an increase in chromosome aberrations and in sister-chromatid exchange (SCE) frequency. The distribution of chromosome breaks throughout the karyotype was non-random and they occurred mainly in the G-negative bands. Certain bands had a marked susceptibility to BUS and comparisons with the human chromosome-break distributions reported for a number of drugs revealed that some of these bands were equally susceptible to other alkylating agents. Both the number of chromosome gaps and breaks and the SCE frequency increased with BUS concentration, but only the SCE dose--response was a clearly defined linear relationship. Therefore a standard SCE dose--response curve was constructed for future comparison with the results of similar investigations of patients on BUS therapy. 相似文献
100.
The apoptotic signals activated by As(2)O(3) in the chronic myelogenous leukemia (CML) cell lines K562 and KCL22 were investigated. As(2)O(3) was found to induce apoptosis in these cells via the intrinsic pathway. As(2)O(3) also induced a sustained c-Jun NH2-terminal kinase (JNK) activation which preceded and was necessary for caspase-9 activation. We established that Rho and its effector, the kinase ROCK, are activated by As(2)O(3). Inhibition of either Rho or ROCK prevented JNK activation and protected against apoptosis. Thus, in CML cells, apoptosis induced by As(2)O(3) is mediated, at least in part, via a Rho-ROCK-JNK axis. These findings define a novel signaling pathway for As(2)O(3)-induced apoptosis. 相似文献