181 research outputs found

    Local delivery of a synthetic endostatin fragment for the treatment of experimental gliomas

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    OBJECTIVE: Endostatin is an anti-angiogenic agent that blocks matrix-metalloproteinase-2 and inhibits endothelial cell proliferation. Currently, endostatin is available through recombinant technology, which limits its broader use. In this study, a synthetic endostatin fragment (EF) was analyzed to determine its anti-angiogenic properties when locally delivered by controlled-release polymers and to establish its effect as a treatment for experimental gliomas. METHODS: Cytotoxicity of EF against 9L gliosarcoma and F98 glioma was determined in vitro. EF was loaded into polyanhydride-poly-(bis- [carboxyphenoxy-propane]-sebacic-acid) (pCPP:SA) polymers at increasing concentrations. Pharmacokinetics of the EF/polymer formulations were defined in vitro. Anti-angiogenic properties of the EF/polymer formulations were evaluated in the rat-cornea micropocket assay. Toxicity and efficacy of locally delivered EF polymers either alone or combined with systemic bischloroethylnitrosourea (carmustine) were determined in rats intracranially challenged with 9L gliosarcoma. RESULTS: EF showed scarce cytotoxicity against 9L and F98 in vitro. EF/pCPP:SA formulations showed sustained release by day 19. Mean corneal angiogenesis index 20 days after tumor implantation was 4.5 (plus or minus) 0.7 for corneas implanted with 40% EF/pCPP:SA compared with controls (8.5 (plus or minus) 1.3, P = 0.02). Intracranial efficacy studies showed that EF polymers alone did not prolong animal survival. Combination of 40% EF/pCPP:SA polymers with systemic bischloroethylnitrosourea (carmustine) prolonged survival (median survival of 44 d, P = 0.001) and generated 33% long-term survivors. CONCLUSION: Controlled-release polymers can effectively deliver a biologically active EF in a sustained fashion. EF inhibits angiogenesis in vitro and in vivo, and even though EF does not prolong survival as a single agent, it exhibits a synergistic effect when combined with systemic bischloroethylnitrosourea (carmustine) in the intracranial 9L gliosarcoma model

    Border effects among Catalan dialects

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    In this study, we investigate which factors influence the linguistic distance of Catalan dialectal pronunciations from standard Catalan. We use pronunciations from three regions where the northwestern variety of the Catalan language is spoken (Catalonia, Aragon and Andorra). In contrast to Aragon, Catalan has an official status in both Catalonia and Andorra, which likely influences standardization. Because we are interested in the potentially large range of differences that standardization might promote, we examine 357 words in Catalan varieties and in particular their pronunciation distances with respect to the standard. In order to be sensitive to differences among the words, we fitted a generalized additive mixed-effects regression model to this data. This allows us to examine simultaneously the general (i.e. aggregate) patterns in pronunciation distance and to detect those words that diverge substantially from the general pattern. The results revealed higher pronunciation distances from standard Catalan in Aragon than in the other regions. Furthermore, speakers in Catalonia and Andorra, but not in Aragon, showed a clear standardization pattern, with younger speakers having dialectal pronunciations closer to the standard than older speakers. This clearly indicates the presence of a border effect within a single country with respect to word pronunciation distances. Since a great deal of scholarship focuses on single segment changes, we compare our analysis to the analysis of three segment changes that have been discussed in the literature on Catalan. This comparison revealed that the pattern observed at the word pronunciation level was supported by two of the three cases examined. As not all individual cases conform to the general pattern,

    Internet of things

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    Manual of Digital Earth / Editors: Huadong Guo, Michael F. Goodchild, Alessandro Annoni .- Springer, 2020 .- ISBN: 978-981-32-9915-3Digital Earth was born with the aim of replicating the real world within the digital world. Many efforts have been made to observe and sense the Earth, both from space (remote sensing) and by using in situ sensors. Focusing on the latter, advances in Digital Earth have established vital bridges to exploit these sensors and their networks by taking location as a key element. The current era of connectivity envisions that everything is connected to everything. The concept of the Internet of Things(IoT)emergedasaholisticproposaltoenableanecosystemofvaried,heterogeneous networked objects and devices to speak to and interact with each other. To make the IoT ecosystem a reality, it is necessary to understand the electronic components, communication protocols, real-time analysis techniques, and the location of the objects and devices. The IoT ecosystem and the Digital Earth (DE) jointly form interrelated infrastructures for addressing today’s pressing issues and complex challenges. In this chapter, we explore the synergies and frictions in establishing an efficient and permanent collaboration between the two infrastructures, in order to adequately address multidisciplinary and increasingly complex real-world problems. Although there are still some pending issues, the identified synergies generate optimism for a true collaboration between the Internet of Things and the Digital Earth

    Grassroots Agency: Participation and Conflict in Buenos Aires Shantytowns seen through the Pilot Plan for Villa 7 (1971–1975)

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    open access articleIn 1971, after more than a decade of national and municipal policies aimed at the top-down removal of shantytowns, the Buenos Aires City Council approved the Plan Piloto para la Relocalización de Villa 7 (Pilot Plan for the Relocation of Shantytown 7; 1971–1975, referred to as the Pilot Plan hereinafter). This particular plan, which resulted in the construction of the housing complex, Barrio Justo Suárez, endures in the collective memory of Argentines as a landmark project regarding grassroots participation in state housing initiatives addressed at shantytowns. Emerging from a context of a housing shortage for the growing urban poor and intense popular mobilizations during the transition to democracy, the authors of the Pilot Plan sought to empower shantytown residents in novel ways by: 1) maintaining the shantytown’s location as opposed to eradication schemes that relocated the residents elsewhere, 2) formally employing some of the residents for the stage of construction, as opposed to “self-help” housing projects in which the residents contributed with unpaid labor, and 3) including them in the urban and architectural design of the of the new housing. This paper will examine the context in which the Pilot Plan was conceived of as a way of re-assessing the roles of the state, the user, and housing-related professionals, often seen as antagonistic. The paper argues that residents’ fair participation and state intervention in housing schemes are not necessarily incompatible, and can function in specific social and political contexts through multiactor proposals backed by a political will that prioritizes grassroots agency

    A systematic review of outcomes reported inpediatric perioperative research: A report from the Pediatric Perioperative Outcomes Group

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    The Pediatric Perioperative Outcomes Group (PPOG) is an international collaborative of clinical investigators and clinicians within the subspecialty of pediatric anesthesiology and perioperative care which aims to use COMET (Core Outcomes Measures in Effectiveness Trials) methodology to develop core outcome sets for infants, children, and young people that are tailored to the priorities of the pediatric surgical population. Focusing on four age‐dependent patient subpopulations determined a priori for core outcome set development: (a) neonates and former preterm infants (up to 60 weeks postmenstrual age); (b) infants (>60 weeks postmenstrual age—1‐13‐<18 years), we conducted a systematic review of outcomes reported in perioperative studies that include participants within age‐dependent pediatric subpopulations. Our review of pediatric perioperative controlled trials published from 2008 to 2018 identified 724 articles reporting 3192 outcome measures. The proportion of published trials and the most frequently reported outcomes varied across predetermined age‐groups. Outcomes related to patient comfort, particularly pain and analgesic requirement, were the most frequent domain for infants, children, and adolescents. Clinical indicators, particularly cardiorespiratory or medication‐related adverse events, were the most common outcomes for neonates and infants <60 weeks and were the second most frequent domain at all other ages. Neonates and infants <60 weeks of age were significantly under‐represented in perioperative trials. Patient‐centered outcomes, healthcare utilization, and bleeding/transfusion‐related outcomes were less often reported. In most studies, outcomes were measured in the immediate perioperative period, with the duration often restricted to the postanesthesia care unit or the first 24 postoperative hours. The outcomes identified with this systematic review will be combined with patient‐centered outcomes identified through a subsequent stakeholder engagement study to arrive at a core outcome set for each age‐specific group

    Functional analysis of Pro-inflammatory properties within the cerebrospinal fluid after subarachnoid hemorrhage in vivo and in vitro

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    <p>Abstract</p> <p>Background</p> <p>To functionally characterize pro-inflammatory and vasoconstrictive properties of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage (SAH) in vivo and in vitro.</p> <p>Methods</p> <p>The cerebrospinal fluid (CSF) of 10 patients suffering from SAH was applied to the transparent skinfold chamber model in male NMRI mice which allows for in vivo analysis of the microcirculatory response to a superfusat. Microvascular diameter changes were quantified and the numbers of rolling and sticking leukocytes were documented using intravital multifluorescence imaging techniques. Furthermore, the pro-inflammatory properties of CSF were assessed in vitro using a monocyte transendothelial migration assay.</p> <p>Results</p> <p>CSF superfusion started to induce significant vasoconstriction on days 4 and 6 after SAH. In parallel, CSF superfusion induced a microvascular leukocyte recruitment, with a significant number of leukocytes rolling (day 6) and sticking (days 2-4) to the endothelium. CSF of patients presenting with cerebral edema induced breakdown of blood vessel integrity in our assay as evidenced by fluorescent marker extravasation. In accordance with leukocyte activation in vivo, significantly higher in vitro monocyte migration rates were found after SAH.</p> <p>Conclusion</p> <p>We functionally characterized inflammatory and vasoactive properties of patients' CSF after SAH in vivo and in vitro. This pro-inflammatory milieu in the subarachnoid space might play a pivotal role in the pathophysiology of early and delayed brain injury as well as vasospasm development following SAH.</p
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