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Building awareness of life-cycle thinking and its value will be an important first step towards creating more sustainable forms of consumption and production. We have come a long way—even though the public may not have heard of it as ‘life-cycle thinking’. Articles in the popular press, which elude to life-cycle implications, are beginning to surface. For example, George F. Will (Newsweek, May 6, 2002) describes the ‘most politically correct product’ as being Ben & Jerry’s ice cream. But he also goes on to mention that their ice cream is “made in a factory that depends on electricity-guzzling refrigeration, and the a gallon of ice cream requires eight gallons of milk. While making that much milk, a cow consumes a lot of water plus three pounds of grain and hay, which is produced with tractor fuel, chemical fertilizers, herbicides, and insecticides, and is transported with truck or train fuel.”  相似文献   
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F. FAVA, P.M. ARMENANTE AND D. KAFKEWITZ. 1995. A Gram-negative aerobic bacterium capable of using 2–chlorophenol (2–CP), 3–chlorophenol (3–CP) and 4–chlorophenol (4–CP) as sole carbon sources was isolated and characterized. The bacterium, designated LD1, was identified to be a Pseudomonas pickettii strain. LD1 was able to totally degrade and dechlorinate 2–CP (initial concentration: 1.51 mmol I-1), 3–CP (initial concentration: 0.57 mmol I-1) and 4–CP (initial concentration: 0.75 mmol I-1) within 30, 30 and 40 h of incubation, respectively, under growing-cell batch conditions. LD1 was also found to be able to metabolize chlorocatechols in growing- and resting-cell conditions. This suggests that the bacterium degrades monochlorophenols through a chlorocatechol pathway. In addition, LD1 was found to be capable of readily metabolizing other organic compounds such as phenol, benzoic acid, hydroxybenzoic acids and hydroquinone.
Because of the broad spectrum of monochlorophenols and organic compounds that LD1 can degrade, this bacterium appears to have the potential for being successfully used in the biotreatment of wastewaters and in soil decontamination.  相似文献   
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BACKGROUND: Excitotoxicity and excess generation of nitric oxide (NO) are believed to be fundamental mechanisms in many acute and chronic neurodegenerative disorders. Disturbance of Ca2+ homeostasis and protein nitration/nitrosylation are key features in such conditions. Recently, a family of proteases collectively known as caspases has been implicated as common executor of a variety of death signals. In addition, overactivation of poly-(ADP-ribose) polymerase (PARP) has been observed in neuronal excitotoxicity. We therefore designed this study to investigate whether triggering of caspase activity and/or activation of PARP played a role in cerebellar granule cell (CGC) apoptosis elicited by peroxynitrite (ONOO-) or NO donors. MATERIALS AND METHODS: CGC from wild-type or PARP -/- mice were exposed to various nitric oxide donors. Caspase activation and its implications for membrane alterations, Ca2+ homeostasis, intracellular proteolysis, chromatin degradation, and cell death were investigated. RESULTS: CGC exposed to NO donors undergo apoptosis, which is mediated by excess synaptic release of excitotoxic mediators. This excitotoxic mechanism differs from direct NO toxicity in some other neuronal populations and does not involve PARP activation. Inhibition of caspases with different peptide substrates prevented cell death and the related features, including intracellular proteolysis, chromatin breakdown, and translocation of phosphatidylserine to the outer surface of the cell membrane. Increased Ca2+ influx following N-methyl-D-aspartate (NMDA) receptor (NMDA-R) activation was not inhibited by caspase inhibitors. CONCLUSIONS: In CGC, NO donors elicit apoptosis by a mechanism involving excitotoxic mediators, Ca2+ overload, and subsequent activation of caspases.  相似文献   
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Large bowel carcinogenesis involves accumulation of genetic alterations leading to transformation of normal mucosa into dysplasia and, lastly, adenocarcinoma. It is pertinent to elucidate the molecular changes occurring in the pre-neoplastic lesions to facilitate early diagnosis and treatment. Heat shock proteins (Hsps), many of which are molecular chaperones, are implicated in carcinogenesis, and their variations with tumor progression encourage their study as biomarkers. There are many reports on Hsps and cancer but none to our knowledge on their systematic quantification in pre-neoplastic lesions of the large bowel. We performed immunohistochemical determinations of Hsp10, Hsp60, Hsp70, and Hsp90 in biopsies of large bowel tubular adenomas with moderate grade of dysplasia and compared to normal mucosa and adenocarcinoma with a moderate grade of differentiation (G2). A significant elevation of Hsp10 and Hsp60 only, i.e., in the absence of elevation of Hsp70 or Hsp90, in both epithelium and lamina propria was found in tubular adenoma by comparison with normal mucosa. In contrast, adenocarcinoma was characterized by the highest levels of Hsp10 and Hsp60 in epithelium and lamina propria, accompanied by the highest levels of Hsp70 only in epithelium and of Hsp90 only in lamina propria, by comparison with normal and tubular adenoma counterparts. Hsp10 and Hsp60 are promising biomarkers for early diagnosis of tubular adenoma and for its differentiation from more advanced malignant lesions. Hsp10 and Hsp60 may be implicated in carcinogenesis from its very early steps and, thus, are potentially convenient targets for therapy.  相似文献   
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