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101.
The human ocular surface is covered by the conjunctival, corneal and limbal stratified epithelia. While conjunctival stem cells are distributed in bulbar and forniceal conjunctiva, corneal stem cells are segregated in the basal layer of the limbus, which is the transitional zone between the cornea and the bulbar conjunctiva. Keratinocyte stem and transient amplifying (TA) cells when isolated in culture give rise to holoclones and paraclones, respectively. Keratinocyte replicative senescence ensues when all holoclones have generated paraclones which express high levels of p16(INK4a). In the present study, we show that enforced telomerase activity induces the bypass of replicative senescence in limbal and conjunctival keratinocytes, without the inactivation of the p16(INK4a)/Rb pathway or the abrogation of p53 expression. hTERT-transduced limbal and conjunctival keratinocytes are capable to respond to both growth inhibitory and differentiation stimuli, since they undergo growth arrest in response to phorbol esters, and activate p53 upon DNA damage. Following a sustained PKC stimulation, occasional clones of p16(INK4a)-negative cells emerge and resume ability to proliferate. Telomerase activity, however, is unable to induce the bypass of senescence in corneal TA keratinocytes cultured under the same conditions. These data support the notion that telomere-dependent replicative senescence is a general property of all human somatic cells, including keratinocytes, and suggest that telomerase activity is sufficient to extend the lifespan only of keratinocytes endowed with high proliferative potentials (which include stem cells), but not of TA keratinocytes.  相似文献   
102.
On the basis of the previous article (Morchio and Traverso [1999]), we discuss the possible interactions between the first proteic fragments developed in the hydrophobic layer made of hydrocarbons, which would have covered the surface of the primitive seas, and the nitrogenous bases, particularly the pyrimidinic ones, which would have found in such hydrophobic layer favourable conditions to their prebiotic synthesis. These interactions would have presumably brought, on the basis of the physicochemical laws, at the moment the only ones at work, to the linkage of various bases and so to the construction of the first nucleic acid chains (most likely RNA). Interestingly enough this result would have been obtained by inserting two more bases between those hydrogen bound to the amino acids and this might have been the ground for the future "triplets". These interactions might have been particularly significant because of two important consequences: the birth of a rough genetic code and the starting of interactions of the co-operative type between bases and amino acids that would have made the growth of both proteic and nucleic acid fragments easier and faster. We conclude that the development of the genetic code was neither a "frozen accident" nor an occurrence directed by any information flow.  相似文献   
103.

Purpose

Whereas the business evolution of environmental sustainability metrics has advanced significantly over the past decade, social sustainability at product level is still relatively immature. Research continues to support the front runners on organisational sustainability, while workable solutions at product level have not yet been addressed sufficiently. Triggered by this imbalance, a group of experts from large companies decided to join forces, initiating the Roundtable for Product Social Metrics.

Methods

Starting in early 2013, this group of companies aimed to (i) consolidate principles for product social sustainability assessment and harmonise approaches, (ii) align with other global initiatives and share with other companies and (iii) develop solutions for cross-cutting implementation issues. In order to be able to produce a comprehensive method for social impact assessment that provides enough flexibility for individual requirements, the Roundtable developed a method based on the approaches of the participant companies and external references such as the UNEP/SETAC Guidelines for Social Life-Cycle Assessment of Products and corporate level standards. Guiding principles were defined for the development of the method.

Results and discussion

The results of the first two phases of the Roundtable for Product Social Metrics are documented in a handbook, which proposes a practical method for organisations to assess the social impacts of a product or a service along its life cycle. The handbook outlines an aligned method for social impact assessment at a product level offering two approaches: quantitative and scale based. The method was developed to allow reasoned assessment of overall performance by including social topics and performance indicators that reflect positive and negative impacts of the product on three stakeholder groups: workers, consumers and local communities. Nineteen social topics are proposed, together with their individual performance indicators, including detailed definitions. Application examples and recommendations for the communication of results are also included in the handbook.

Conclusions

The method can be applied in numerous scenarios, from understanding improvement opportunities and steering product development in different stages, to providing support for decision making and external communications. However, the method still has further potential for improvement, inter alia that the proposed indicators are not fully applicable to small farmers, SMEs and the self-employed, as well as that the indicators are mainly at inventory level. Furthermore, the proposed method is strongly dependent on the availability of data.
  相似文献   
104.

Purpose

The main goal of this paper is to present the feasibility of the quantitative method presented in the Product Social Impact Assessment (PSIA) handbook throughout a case study. The case study was developed to assess the social impacts of a tire throughout its entire life cycle. We carried out this case study in the context of the Roundtable for the Product Social Metrics project in which 13 companies develop two methodologies, a qualitative and a quantitative one, for assessing the social impact of product life cycle.

Methods

The quantitative methodology implemented for assessing the social impact of a Run On Flat tire mounted in a BMW 3 series consists of 26 indicators split in three groups. Each group represents a stakeholder group. Primary data of the quantitative indicators were collected along the product life cycle of the Run On Flat by involving the companies, which owned the main steps of the product life cycle. Throughout this case study, an ideal/worst-case scenario was defined for the distance-to-target approach to compare the social performances of more products when they are available.

Results and discussion

The implementation of the PSIA quantitative method to a Run On Flat illustrated the necessity to have a referencing step in order to interpret the results. This is particularly important when the results are used to support decision-making process in which no experts are involved. It frequently happens in a big company where the management level has to take often decisions on different topics. Reference values were defined using ideal or worst-case-target scenarios (Fontes et al. 2014). For those topics where it was possible, an ideal/ethical scenario was defined, e.g., 0 h of child labor per product. In other cases, we defined a worst-case scenario, e.g., 0 training hours per product. It was then possible to interpret the results using a distance-to-target approach. A matrix was developed in the case study for identifying in which step of the product life cycle data is not available; that means we need more transparency in the supply chain.

Conclusions

Each value of the matrix can be compared to the ideal/worst scenario to compare the step to each other and to identify along the product life cycle which step and the relative supplier that needs further measures to improve the product performance. Furthermore, a quantitative value for each indicator related to the product life cycle is calculated and compared with the ideal/worst scenario. The case study on Run On Flat represents the first implementation of the quantitative method of PSIA.
  相似文献   
105.

Purpose

The main purpose of this study is to present an implementation of the subcategory assessment method (SAM) to the life cycle of an Italian variety of tomato called “Cuore di Bue” produced by an Italian cooperative. The case study was used to use the methodology proposed in compliance with the guidelines of social life cycle assessment (S-LCA) in order to highlight issues for the improvement of SAM. A summary of strengths and weaknesses of the methodology as well as the social performance of the considered Italian tomato is an important result of this case study.

Methods

The methodology used is based on SAM. The UNEP/SETAC guidelines of S-LCA and the complementary methodological sheets were used as main references to carry out SAM, and it was used to assess the social performances of Cuore di Bue. The focus was on the assessment of the following three out of five stakeholder groups presented in the guidelines: workers, local community and consumers. Specific questionnaires have been developed to collect the inventory data related to each stakeholder group and along the product life cycle.

Results and discussion

SAM of Cuore di Bue showed a range of values, between 2 and 3 (C-B) for consumer stakeholder group and mainly 3 (B) for the local community and worker stakeholders. Because the best performance (A) is related to a numerical value of 4, better performances were not identified, owing to no propagation of actions in the value chain. The collective bargaining, transparency, feedback mechanism and privacy are the subcategories with the worst performance, but at the same time with more potential for improvements.

Conclusions

The implementation of SAM on Cuore di Bue allowed us to demonstrate how SAM transforms qualitative data into semi-quantitative information through a score scale that can help a decision maker achieve a product overview. SAM has been implemented on Cuore di Bue; the product assessment, the strengths and weaknesses of the methodology are identified and discussed as well. It has been possible to present the best and worst performances in product life cycle, by identifying the phase or the subcategories with good or bad performance. However, in this case study, as the same company owns most of the product life cycle taken into account, the majority of social performances are identical, and this may represent a limit of the methodology or that more organisations along the life cycle must be taken into account (for example, energy, distribution).
  相似文献   
106.

Background

Anti-tumor vaccination is a new frontier in cancer treatment applicable to immunogenic neoplasms such as prostate and renal cancers. GX301 is a vaccine constituted by four telomerase peptides and two adjuvants, Montanide ISA-51 and Imiquimod.

Objective

The aim of this study was to analyze safety and tolerability of GX301 in an open-label, phase I/II trial. Immunological and clinical responses were also evaluated as secondary endpoints.

Experimental design

GX301 was administered by intradermally injecting 500 μg of each peptide (dissolved in Montanide ISA-51) in the skin of the abdomen. Imiquimod was applied as a cream at the injection sites. The protocol included 8 administrations at days 1, 3, 5, 7, 14, 21, 35, 63. Eligible patients were affected with stage IV prostate or renal cancer resistant to conventional treatments. Patients were clinically and immunologically monitored up to 6 months from the first immunization.

Results

No grade 3–4 adverse events were observed. Evidence of vaccine-specific immunological responses was detected in 100 % of patients. Disease stabilization occurred in 4 patients. Prolonged progression-free survival and overall survival were observed in patients showing a full pattern of vaccine-specific immunological responses.

Conclusion

GX301 demonstrated to be safe and highly immunogenic. Further studies are needed to determine its clinical efficacy.  相似文献   
107.
One of the most critical modifications affecting the N‐terminus of proteins is N‐myristoylation. This irreversible modification affects the membrane‐binding properties of crucial proteins involved in signal transduction cascades. This cotranslational modification, catalyzed by N‐myristoyl transferase, occurs both in lower and higher eukaryotes and is a validated therapeutic target for several pathologies. However, this lipidation proves very difficult to be evidenced in vivo even with state‐of‐the‐art proteomics approaches or bioinformatics tools. A large part of N‐myristoylated proteins remains to be discovered and the rules of substrate specificity need to be established in each organism. Because the peptide substrate recognition occurs around the first eight residues, short peptides are used for modeling the reaction in vitro. Here, we provide a novel approach including a dedicated peptide array for high‐throughput profiling protein N‐myristoylation specificity. We show that myristoylation predictive tools need to be fine‐tuned to organisms and that their poor accuracy should be significantly enhanced. This should lead to strongly improved knowledge of the number and function of myristoylated proteins occurring in any proteome.  相似文献   
108.

Purpose

Technologies can contribute to sustainable development (e.g., improving living conditions) and at the same time cause sustainability problems (e.g., emissions). Decisions on alternative technologies should thus ideally be based on the principle to minimize the latter. Analyzing environmental, economic, and social aspects related to technologies supports decisions by identifying the “more sustainable” technology. This paper focuses on social issues. First, it discusses the applicability of the social life cycle assessment (SLCA) guidelines for a comparative technology analysis, taking the example of two case studies in developing countries. Indicating technologies as “sustainable” also means that they are indeed operated over the expected lifetime, which, in development projects, is often not guaranteed. Consequently, social aspects related to implementation conditions should be considered in an SLCA study as well. Thus, a second focus is laid on identifying appropriate indicators to address these aspects.

Methods

First, the SLCA guidelines were examined with regard to applying this product-related approach to two real case studies (analysis of technologies/plants for water supply and for decentralized fuel production) for a comparative technology analysis. Suitable indicators are proposed. To address the second focus, a literature research on technology assessment and implementation in developing countries was conducted. Moreover, socioeconomic studies in the investigation areas of the case studies were consulted. Based on this, indicators addressing implementation conditions were identified from the SLCA guidelines and additional literature.

Results and discussion

The study shows social issues and indicators found in the SLCA guidelines and considered suitable for a comparative technology analysis in the case studies. However, for a sustainability assessment of technologies, especially in developing countries, further indicators are required to address technology implementation conditions. A set of additional social indicators like reported trust in institutions or fluctuation of personnel is proposed. Though these indicators were derived based on specific case studies, they can also be suggested to other technologies and are not necessarily limited to developing countries.

Conclusions

The study pointed out that an application of the SLCA guidelines considering the whole life cycle was not (yet) feasible for the case studies considered. This is mainly due to the lack of data. Regarding technology implementation, it was examined which indicators are available in this SLCA approach and which could additionally be integrated and applied. This is relevant as a potential contribution of technologies to sustainable development can only be achieved when the technologies are successfully implemented.  相似文献   
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