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Intravesical application of bacillus Calmette-Guérin (BCG) is highly active against recurrences of superficial urothelial bladder carcinoma. In an attempt to monitor the immunological effects of this therapy, we analyzed the urine of patients following the sixth intravessical instillation, to show the presence of the monokines TNF and IL 1 and the lymphokine IL 2. Within 24 hours following the instillation, all (n = 10) patients exhibited a strong increase in urinary cytokine secretion, which was significantly different from the control group (n = 10), with respect to TNF L929 biological assay (P less than 0.01), TNF sandwich-ELISA (P less than 0.01), IL 2 CTL 6 biological assay (P less than 0.05), IL 2 sandwich-ELISA (P less than 0.005), and IL 1 sandwich-ELISA (P less than 0.05), but not to the IL 1 fibroblast biological assay. The maximum urinary secretion varied between individual patients and different cytokines, but was generally found within 2 to 8 hr after the instillation. A persistent high urinary activity was demonstrated in BCG-treated patients for IL 2 in sandwich-ELISA. These results reflect the local inflammatory response to BCG and suggest an immunomodulatory mode of action against urothelial carcinoma cells. Elucidation of the possible role of each urinary cytokine against this cancer warrants further investigations.  相似文献   
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Early dissemination of malignant cells is the main cause for metastatic relapse in patients with solid tumours. By use of monoclonal antibodies (mAbs) specific for cytokeratins, disseminated individual epithelial tumour cells can now be identified in mesenchymal organs such as bone marrow. Further to characterize such cells in patients with prostate cancer, an immunocytochemical procedure was developed for simultaneous labelling of cytokeratin component no. 18 (CK18) and prostate specific antigen (PSA). In a first step, cells were incubated with mAb ER-PR8 against PSA and secondary gold-conjugated goat anti-mouse antibodies. In a second step, biotinylated mAb CK2 to CK18 was applied as primary antibody and subsequently incubated with complexes of streptavidin-conjugated alkaline phosphatase, which were developed with the Newfuchsin substrate. The binding of gold-labelled antibodies was visualized by silver enhancement. The sensitivity and specificity of the technique was demonstrated on cryostat sections of hyperplastic prostatic tissue, and cytological preparations of LNCaP prostatic tumour cells. Double staining was restricted to cells derived from the secretory epithelium of the prostate. Cross-reactivity between both detection systems was excluded by several controls, including the use of unrelated antibodies of the same isotype and the staining of CK18+/PSA HT29 colon carcinoma cells. CK18+ cells co-expressing PSA were found in bone marrow aspirates from 5 out of 13 patients with carcinomas of the prostate, a finding that is consistent with the relative fraction of double-positive LNCaP cells. The specificity of CK18 for epithelial tumour cells in bone marrow was supported by negative staining of 12 control aspirates from patients with benign prostatic hypertrophy. In conclusion, the approach presented appears to be a reliable method to phenotype individual prostatic carcinoma cells.  相似文献   
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Biological Invasions - Oystershell scale (OSS; Lepidosaphes ulmi) is an emerging invasive insect that poses a serious threat to conservation of quaking aspen (Populus tremuloides) in the...  相似文献   
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Lengthened circadian period of locomotor activity is a characteristic of a congenic strain of mice carrying a nonsense mutation in exon 5 of the carbonic anhydrase II gene, car2. The null mutation in car2 is located on a DBA/2J inbred strain insert on proximal chromosome 3, on an otherwise C57BL/6J genomic background. Since reducing the size of the congenic region would narrow the possible candidate genes for period, two recombinant congenic strains (R1 and R2) were developed from the original congenic strain. These new congenic strains were assessed for period, genetic composition, and the presence of immunoreactive carbonic anhydrase II. R1 mice were homozygous DBA/2J for the distal portion of the original DBA/2J insert, while R2 mice were homozygous DBA/2J for the proximal portion. R1 mice had a significantly lengthened period compared to R2 mice and wild-type C57BL/6J mice, indicating that the gene(s) affecting period is likely found within the reduced DBA/2J insert (~1 cM) in the R1 mice. The R1 mice also possessed the null mutation in car2. This study confirmed the presence of a gene(s) affecting period on proximal chromosome 3 and significantly reduced the size of the congenic region and the number of candidate genes. Future studies will focus on identifying the gene influencing period.  相似文献   
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Proteolytic activation of zymogens or controlled degradation of inhibitory factors is part of a major regulatory system on the post-translational level to regulate treatment induced cellular stress responses. The identification of differential activity based substrates is thus of high interest to prioritize and validate candidate targets for drug discovery. Here we present a novel subtractive substrate phage display screening method for the selection of treatment induced post-translational peptide modifications in complex proteomes. We investigated this approach with tumor cells in response to a protease activating anticancer treatment modality using subtractive and iterative screening of cellular extracts derived from control and treated cells. Specific phage were identified that served as substrates for proteolytic activities in response to treatment related activity changes and could be distinguished from substrates for unspecific proteolytic background activities. Novel, selected peptide substrates were investigated in vitro and in vivo and showed high substrate specificity and functional biological significance.  相似文献   
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Background  In Life-Cycle Assessment (LCA), decision makers are often faced with tradeoffs between current and future impacts. One typical example is waste incineration, where immediate emissions to the air from the incineration process have to be weighted against future emissions of slag landfills. Long-term impacts are either completely taken into account or they are entirely disregarded in case of a temporal cut-off. Temporal cutoffs are a special case of discounting. Objective  In this paper, discounting is defined as valuing damages differently at different points of time using a positive or negative discount rate. Apart from temporal cut-offs, discounting has rarely been applied in LCA so far. It is the goal of this paper to discuss the concept of discounting and its applicability in the context of LCA. Methods  For this purpose, we first review the arguments for discounting and its principles in economic sciences. Discounting in economics can be motivated by pure time preference, productivity of capital, diminishing marginal utility of consumption, and uncertainties. The nominal discount rate additionally includes changes in the price level. These arguments and their justification are discussed in the context of environmental impacts harming future generations. Results and Discussion  It is concluded that discounting across generations because of pure time preference contradicts fundamental ethical values and should therefore not be applied in LCA. However, it has to be acknowledged that in practice decision makers often use positive discount rates because of pure time preference — either because they might profit from imposing environmental damage on others instead of themselves or because people in the far future are not of immediate concern to them. Discounting because of the productivity of capital assumes a relationship between monetary values and environmental impact. If such a relationship is accepted, discounting could be applied. However, future generations should be compensated for the environmental damage. It is likely that they would demand a higher compensation if the real per capita income increases. As both the compensation and the discount rate are related to economic growth, the overall discount rate might be close to zero. It is shown that the overall discount rate might even be negative considering that the required compensation could increase (even to infinite) if natural assets remain scarce, whereas the utility of consumption diminishes with increasing income. Uncertainties could justify both positive and negative discount rates. Since the relationship between uncertainties and the magnitude of damage is generally not exponential, we recommend to model changes in the magnitude of damage in scenario analysis instead of considering it in discounting (which requires an exponential function of time in the case of a constant discount rate). We investigated the influence of discounting in a case study of heavy metal emissions from slag landfills. It could be shown that even small discount rates of less than 1 % lead to a significant reduction of the impact score, whereas negative discount rates inflate the results. Conclusions and Recommendations  Discounting is only applicable when temporally differentiated data is available. In some cases, such a temporal differentiation is necessary to take sound decisions, especially when long emission periods are involved. An example is the disposal of nuclear or heavy metal-containing waste. In these cases, the results might completely depend on the discount rate. This paper helps to structure arguments and thus to support the decision about whether or not discounting should be applied in an LCA.  相似文献   
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When one models impact pathways due to stressors that are caused by the provision of product systems, it results in indicators for environmental damages. These indicators are incommensurable and cannot be compared per se. For example, the statistical life years lost for a human population cannot necessarily be compared with the potentially affected fraction of species within an ecosystem. However, some decision makers who use life-cycle assessment (LCA) prefer a single index, because it facilitates interpretation better than a multi-indicator system. This requires a method for aggregating environmental damages of differing types, thereby confronting LCA with a valuation problem.
The article describes a nonmonetary approach to valuation in LCA that incorporates the findings of a survey among LCA practitioners and users. The survey focuses on the weighting of three safeguard subjects for Eco-indicator 99, a damage-oriented impact-assessment method: human health, ecosystem quality, and resources. Of particular interest here is what influence the context provided in the survey (framing) and an individual's characteristics have on his or her weighting of environmental damages. The results indicate that damages on the European level are easier to compare than damages on a micro level. Additionally, although only half of the survey participants could be classified unequivocally into one of three cultural perspectives, each perspective rated the damage categories presented to them significantly differently from the others. Our conclusions were that framing effects need to be more carefully considered in weighting procedures and that weighting preferences vary significantly according to a group's archetypical attitudes.  相似文献   
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