8 research outputs found

    Pregabalin Add-On vs. Dose Increase in Levetiracetam Add-On Treatment: A Real-Life Trial in Dogs With Drug-Resistant Epilepsy

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    Epilepsy is a common neurological disorder affecting 0.6–0.75% of dogs in veterinary practice. Treatment is frequently complicated by the occurrence of drug-resistant epilepsy and cluster seizures in dogs with idiopathic epilepsy. Only few studies are available to guide treatment choices beyond licensed veterinary drugs. The aim of the study was to compare antiseizure efficacy and tolerability of two add-on treatment strategies in dogs with drug-resistant idiopathic epilepsy. The study design was a prospective, open-label, non-blinded, comparative treatment trial. Treatment success was defined as a 3-fold extension of the longest baseline interseizure interval and to a minimum of 3 months. To avoid prolonged adherence to a presumably ineffective treatment strategy, dog owners could leave the study after the third day with generalized seizures if the interseizure interval failed to show a relevant increase. Twenty-six dogs (mean age 5.5 years, mean seizure frequency 4/month) with drug-resistant idiopathic epilepsy and a history of cluster seizures were included. Dogs received either add-on treatment with pregabalin (PGB) 4 mg/kg twice daily (14 dogs) or a dose increase in levetiracetam (LEV) add-on treatment (12 dogs). Thirteen dogs in the PGB group had drug levels within the therapeutic range for humans. Two dogs in the PGB group (14.3%; 2/14) and one dog in the LEV group (8.3%; 1/12) achieved treatment success with long seizure-free intervals from 122 to 219 days but then relapsed to their early seizure frequency 10 months after the study inclusion. The overall low success rates with both treatment strategies likely reflect a real-life situation in canine drug-resistant idiopathic epilepsy in everyday veterinary practice. These results delineate the need for research on better pharmacologic and non-pharmacologic treatment strategies in dogs with drug-resistant epilepsy

    The role of versican isoforms V0/V1 in glioma migration mediated by transforming growth factor-β2

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    Versican is a large chondroitin sulphate proteoglycan produced by several tumour cell types, including high-grade glioma. The increased expression of certain versican isoforms in the extracellular matrix (ECM) plays a role in tumour cell growth, adhesion and migration. Transforming growth factor-β2 (TGF-β2) is an important modulator of glioma invasion, partially by remodeling the ECM. However, it is unknown whether it interacts with versican during malignant progression of glioma cells. Here, we analysed the effect of TGF-β2 on the expression of versican isoforms. The expression of versican V0/V1 was upregulated by TGF-β2 detected by quantitative polymerase chain reaction and immunoprecipitation, whereas V2 was not induced. Using time-lapse scratch and spheroid migration assays, we observed that the glioma migration rate is significantly increased by exogenous TGF-β2 and inhibited by TGF-β2-specific antisense oligonucleotides. Interestingly, an antibody specific for the DPEAAE region of glycosaminoglycan-β domain of versican was able to reverse the effect of TGF-β2 on glioma migration in a dose-dependent manner. Taken together, we report here that TGF-β2 triggers the malignant phenotype of high-grade gliomas by induction of migration, and that this effect is, at least in part, mediated by versican V0/V1

    An imbalance between Smad and MAPK pathways is responsible for TGF-beta tumor promoting effects in high-grade gliomas

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    The transforming growth factor-beta (TGF-beta) plays a pivotal role in the pathobiology of human gliomas: during carcinogenesis, it turns from a tumor suppressor to a tumor promoter. The traditional Smad pathway and the more recently discovered MAPK pathway are the most important pathways for TGF-beta related intracellular signal transduction mediating differential pathobiological effects. In this study, we investigated the effects of TGF-beta2 and the TGF-beta2 antisense phosphorothioate oligodeoxynucleotide (PTO) AS-11 on the functionality of both the Smad and MAPK pathways in high-grade gliomas. We aimed to correlate the imbalance between the pathways with differences in the behaviour of high-grade glioma cells. Gene and protein expression studies were used to detect levels of members of the Smad and MAPK pathways under regulation of TGF-beta2 and AS-11. Proliferation and migration assays were functional readouts for effects caused by these regulating tools. Gene arrays were used to detect yet unknown regulators of these functional effects. The Smad pathway was functional in the tested cell lines. Exogenous TGF-beta2 inhibited proliferation but enhanced migration. Smad 2 mRNA expression and activation were significantly reduced by incubation with AS-11. K-ras was reduced both in gene arrays and quPCR under treatment with AS-11, but there was no influence of K-ras down-regulation on the activity of ERK. Ubiquitination-related genes also were specifically down-regulated with AS-11. Our results indicate the involvement of K-ras in TGF-beta signaling in high-grade gliomas. ERK, which is a member of the MAPK pathway, was not influenced and seems to be activated through RAS independent cascades in glioma. These results suggest that combined antagonization of the TGF-beta and MAPK pathways might be a promising approach for glioma therapy. An imbalance between these two pathways might be responsible for TGF-beta switching to a tumor promoter protein in high-grade gliomas

    Inference management, trust and obfuscation principles for quality of information in emerging pervasive environments

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    The emergence of large scale, distributed, sensor-enabled, machine-to-machine pervasive applications necessitates engaging with providers of information on demand to collect the information, of varying quality levels, to be used to infer about the state of the world and decide actions in response. In these highly fluid operational environments, involving information providers and consumers of various degrees of trust and intentions, information transformation, such as obfuscation, is used to manage the inferences that could be made to protect providers from misuses of the information they share, while still providing benefits to their information consumers. In this paper, we develop the initial principles for relating to inference management and the role that trust and obfuscation plays in it within the context of this emerging breed of applications. We start by extending the definitions of trust and obfuscation into this emerging application space. We, then, highlight their role as we move from the tightly-coupled to loosely-coupled sensory-inference systems and describe how quality, value and risk of information relate in collaborative and adversarial systems. Next, we discuss quality distortion illustrated through a human activity recognition sensory system. We then present a system architecture to support an inference firewall capability in a publish/subscribe system for sensory information and conclude with a discussion and closing remarks.US Army Research Laboratory ; UK Ministry of Defence ; TÃœBÄ°TA

    Expression levels of melanoma inhibitory activity correlate with time to progression in patients with high-grade glioma

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    Melanoma inhibitory activity (MIA) is related to disease progression in patients with malignant melanoma and to invasion and metastasis of melanoma in vivo and in vitro. An alternative splice product termed MIA(splice) was described recently. In addition to melanoma, both proteins are expressed in a substantial subset of high-grade gliomas. We hypothesize that expression levels of both proteins correlate with early tumor progression and parameters of disseminated disease in patients with high-grade glioma. We examined the correlation of expression levels of MIA and MIA(splice) with time to progression and morphological and clinical markers of disseminated disease (defined as multifocal occurrence, gliomatosis, invasion or metastasis) in a series of 24 newly-diagnosed human high-grade gliomas. Homogenates of surgical specimens, cell cultures and blood samples were analyzed. Significant levels of MIA and MIA(splice) protein were detected in 71% of homogenates of high-grade glioma, but not in the related blood samples. Patients with early tumor progression had lower expression levels of MIA than patients with late progression, and the expression level of MIA was inversely related to time to progression. In addition, MIA expression correlated with a high fiber content of the extracellular matrix, suggesting a role in dissemination as known from malignant melanoma. Expression levels of MIA in homogenates of surgical specimen directly relate to a more benign clinical prognosis in patients with high-grade glioma. While a mechanistic relation has not yet been verified, factors such as a high fiber content of the extracellular matrix may explain this observation
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