95 research outputs found

    Considering security and quality of service in SLS to improve policy-based management of multimedia services

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    This paper proposes to improve policy-based management by integrating security parameters into the Service Level Specification (SLS). Integrating those parameters in the QoS part of the Service Level Agreement (SLA) specification is of particular importance for multimedia services requiring security since QoS is negotiated when the multimedia service is deployed. Security mechanisms need to be negotiated at that time when sensible multimedia information is exchanged. In this paper we show that including security parameters in SLA specification improves the negotiation and deployment of security and QoS policies for multimedia services. The parameters this paper proposes to integrate have the advantage to be understandable by end-users and service providers. © 2007 IEEE

    Improving the SLA-based management of QoS for secure multimedia services

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    This paper proposes to integrate security parameters into the Service Level Specification (SLS) template proposed in the Tequila project to improve SLA-based management of QoS [8], [21]. Integrating those parameters in the QoS part of the Service Level Agreement (SLA) specification is essential in particular for secure multimedia services since the QoS is negotiated when the multimedia service is deployed. Security mechanisms need to be negotiated at deployment time when sensible multimedia information is exchanged. In this paper we show that including security parameters in the SLA specification improves the SLA-based management of QoS and therefore the negotiation, deployment and use of the secure multimedia service. The parameters this paper proposes to integrate have the advantage to be understandable by both the end-users and service providers. © IFIP International Federation for Information Processing 2005

    Microtubule interfering agents and KSP inhibitors induce the phosphorylation of the nuclear protein p54(nrb), an event linked to G2/M arrest

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    Microtubule interfering agents (MIAs) are anti-tumor drugs that inhibit microtubule dynamics, while kinesin spindle protein (KSP) inhibitors are substances that block the formation of the bipolar spindle during mitosis. All these compounds cause G2/M arrest and cell death. Using 2D-PAGE followed by Nano-LC-ESI-Q-ToF analysis, we found that MIAs such as vincristine (Oncovin) or paclitaxel (Taxol) and KSP inhibitors such as S-tritil-l-cysteine induce the phosphorylation of the nuclear protein p54(nrb) in HeLa cells. Furthermore, we demonstrate that cisplatin (Platinol), an anti-tumor drug that does not cause M arrest, does not induce this modification. We show that the G2/M arrest induced by MIAs is required for p54(nrb) phosphorylation. Finally, we demonstrate that CDK activity is required for MIA-induced phosphorylation of p54(nrb)

    Characterization of cell death induced by vinflunine, the most recent Vinca alkaloid in clinical development

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    Vinflunine, the most recent Vinca alkaloid in clinical development, demonstrated superior antitumour activity to other Vincas in preclinical tumour models. This study aimed to define its molecular mechanisms of cell killing in both parental sensitive and vinflunine-resistant P388 leukaemia cells. Vinflunine treatment of these cells resulted in apoptosis characterized by DNA fragmentation and proteolytic cleavage of poly-(ADP-ribose) polymerase. Apoptosis-inducing concentrations of vinflunine caused c-Jun N-terminal kinase 1 stimulation, as well as caspases-3/7 activation. This activation of caspases and the induction of apoptosis could be inhibited by the caspase inhibitor acetyl-Asp-Glu-Val-Asp-aldehyde. Interestingly, the apoptosis signal triggered by vinflunine in these P388 cells was not mediated through Bcl-2 phosphorylation. In addition, when vinflunine resistance was developed in P388 cells, it was associated with resistance to vinflunine-induced apoptosis, as reflected by a loss of capacity to induce DNA fragmentation and PARP degradation, and characterized by increased levels of Bcl-2 and Bfl-1/A1. Therefore, these data indirectly implicate Bcl-2 and Bfl-1/A1 in vinflunine-induced cell death mechanisms

    Long-term outcomes of CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) in a consecutive series of 12 patients.

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    BACKGROUND: Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a central nervous system inflammatory disease. OBJECTIVE: To describe the disease course of CLIPPERS. DESIGN: A nationwide study was implemented to collect clinical, magnetic resonance imaging, cerebrospinal fluid, and brain biopsy specimen characteristics of patients with CLIPPERS. SETTING: Academic research. PATIENTS: Twelve patients with CLIPPERS. MAIN OUTCOME MEASURES: The therapeutic management of CLIPPERS was evaluated. RESULTS: Among 12 patients, 42 relapses were analyzed. Relapses lasted a mean duration of 2.5 months, manifested frequent cerebellar ataxia and diplopia, and were associated with a mean Expanded Disability Status Scale (EDSS) score of 4. Besides typical findings of CLIPPERS, magnetic resonance imaging showed brainstem mass effect in 5 patients, extensive myelitis in 3 patients, and closed ring enhancement in 1 patient. Inconstant oligoclonal bands were found on cerebrospinal fluid investigation in 4 patients, with an increased T-cell ratio of CD4 to CD8. Among 7 available brain biopsy specimens, staining was positive for perivascular CD4 T lymphocytes in 5 samples. Thirty-eight of 42 relapses were treated with pulse corticosteroid therapy, which led to improvement, with a mean residual EDSS score of 1.9 (range, 0-7). In 1 patient with untreated relapses, scores on the EDSS progressively increased to a score of 10 at death. Among 5 patients without long-term corticosteroid therapy, the mean annualized relapse rate was 0.5 (range, 0.25-2.8). Among 7 patients taking oral corticosteroids, no relapses occurred in those whose daily dose was 20 mg or higher. No progressive course of CLIPPERS was observed. Four patients with a final EDSS score of 4 or higher had experienced previous severe relapses (EDSS score, ≥5) and brainstem and spinal cord atrophy. CONCLUSIONS: CLIPPERS is a relapsing-remitting disorder without progressive forms. Long-term disability is correlated with the severity of previous relapses. Further studies are needed to confirm that prolonged corticosteroid therapy prevents further relapses.journal article2012 Julimporte

    A Comparative Study of Policy Specification Languages for Secure Distributed Applications

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    This paper presents a comparative study of policy specification languages. Our objective is to find policy language or notation that is the most suitable to express the security aspects of distributed applications running on policy-based networks. We first made a selection of languages and we compare them on several criteria: their suitability to specify security, their ability to express both user and network oriented security aspects, the representation technique they use and the notions they are able to express. This paper concludes on a discussion on what would be the ideal policy language for distributed applications that have strong security constraints
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