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551.
Alastair I. Matheson Lisa E. Manhart Patricia B. Pavlinac Arianna R. Means Adam Akullian Gillian A. Levine Julie Jacobson Erin Shutes Judd L. Walson 《PloS one》2014,9(5)
Background
As new interventions to reduce childhood mortality are identified, careful consideration must be given to identifying populations that could benefit most from them. Promising reductions in childhood mortality reported in a large cluster randomized trial of mass drug administration (MDA) of azithromycin (AZM) prompted the development of visually compelling, easy-to-use tools that synthesize country-specific data on factors that would influence both potential AZM benefit and MDA implementation success.Methodology/Principal Findings
We assessed the opportunity to reduce mortality and the feasibility of implementing such a program, creating Opportunity and Feasibility Indices, respectively. Countries with high childhood mortality were included. A Country Ranking Index combined key variables from the previous two Indices and applied a scoring system to identify high-priority countries. We compared four scenarios with varying weights given to each variable.Twenty-five countries met inclusion criteria. We created easily visualized tools to display the results of the Opportunity and Feasibility Indices. The Opportunity Index revealed substantial variation in the opportunity for an MDA of AZM program to reduce mortality, even among countries with high overall childhood mortality. The Feasibility Index demonstrated that implementing such a program would be most challenging in the countries that could see greatest benefit. Based on the Country Ranking Index, Equatorial Guinea would benefit the most from the MZA of AZM in three of the four scenarios we tested.Conclusions/Significance
These visually accessible tools can be adapted or refined to include other metrics deemed important by stakeholders, and provide a quantitative approach to prioritization for intervention implementation. The need to explicitly state metrics and their weighting encourages thoughtful and transparent decision making. The objective and data-driven approach promoted by the three Indices may foster more efficient use of resources. 相似文献552.
Arianna Aricò Serena Ferraresso Silvia Bresolin Laura Marconato Stefano Comazzi Geertruy Te Kronnie Luca Aresu 《PloS one》2014,9(11)
Canine Diffuse Large B-cell Lymphoma (cDLBCL) is an aggressive cancer with variable clinical response. Despite recent attempts by gene expression profiling to identify the dog as a potential animal model for human DLBCL, this tumor remains biologically heterogeneous with no prognostic biomarkers to predict prognosis. The aim of this work was to identify copy number aberrations (CNAs) by high-resolution array comparative genomic hybridization (aCGH) in 12 dogs with newly diagnosed DLBCL. In a subset of these dogs, the genetic profiles at the end of therapy and at relapse were also assessed. In primary DLBCLs, 90 different genomic imbalances were counted, consisting of 46 gains and 44 losses. Two gains in chr13 were significantly correlated with clinical stage. In addition, specific regions of gains and losses were significantly associated to duration of remission. In primary DLBCLs, individual variability was found, however 14 recurrent CNAs (>30%) were identified. Losses involving IGK, IGL and IGH were always found, and gains along the length of chr13 and chr31 were often observed (>41%). In these segments, MYC, LDHB, HSF1, KIT and PDGFRα are annotated. At the end of therapy, dogs in remission showed four new CNAs, whereas three new CNAs were observed in dogs at relapse compared with the previous profiles. One ex novo CNA, involving TCR, was present in dogs in remission after therapy, possibly induced by the autologous vaccine. Overall, aCGH identified small CNAs associated with outcome, which, along with future expression studies, may reveal target genes relevant to cDLBCL. 相似文献
553.
Blardi P de Lalla A Pieragalli D De Franco V Meini S Ceccatelli L Auteri A 《Prostaglandins & other lipid mediators》2006,80(3-4):175-182
BACKGROUND: Iloprost, a prostacyclin analogue, is used in the treatment of peripheral arterial occlusive disease at Leriche-Fontaine stages III-IV, through intravenous infusion for at least 21 days. Recently, iloprost has been shown to be safe and effective in critical limb ischemia patients when administered per 7 days. We investigated in patients at Leriche-Fontaine stages III-IV the effect of 1-week treatment with iloprost on plasma asymmetric dimethylarginine (ADMA), plasma and platelet serotonin, and on clinical response. METHODS AND RESULTS: Twenty-four critical limb ischemia patients (16 men and 8 women, mean age 76+/-9.7 years) were included in the study and treated with intravenous iloprost (titrated from 0.5 up to 1.5 ng/kg/min) for 16 h a day for seven consecutive days. Blood samples were drawn before infusion on days 1, 4 and 8 of treatment, under the same conditions. Clinical assessment was performed by clinical evaluation, ankle/brachial pressure index and treadmill exercise test. During treatment with iloprost patients clinically improved and plasma levels of ADMA significantly decreased (p<0.001). We also observed a significant increase of serotonin (p<0.01) in platelets and a significant decrease of serotonin (p<0.001) in plasma. Similar variations of ADMA and serotonin were found in two subgroups of patients, diabetics and non-diabetics. CONCLUSIONS: One-week treatment with iloprost in critical limb ischemia patients induced changes of peripheral markers of endothelial dysfunction and atherosclerosis, such as ADMA and serotonin, associated to a clinical improvement. 相似文献
554.
Arianna Servili Mary Rose Bufalino Ryuhei Nishikawa Ivan Sanchez de Melo Jose A. Muñoz-Cueto Lucy E.J. Lee 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,152(2):245-254
Long term cell cultures could be obtained from brains of adult sea bass (Dicentrarchus labrax) up to 5 days post mortem. On three different occasions, sea bass brain tissues were dissected, dispersed and cultured in Leibovitz's L-15 media supplemented with 10% fetal bovine serum. The resulting cellular preparations could be passaged within 2 or 3 weeks of growth. The neural cells derived from the first trial (SBB-W1) have now been passaged over 24 times within two years. These cells have been cryopreserved and thawed successfully. SBB-W1 cells are slow growing with doubling times requiring at least 7 days at 22 °C. These long term cell cultures could be grown in suspension as neurospheres that were immunopositive for nestin, a marker for neural stem cells, or grown as adherent monolayers displaying both glial and neural morphologies. Immunostaining with anti-glial fibrillary acidic protein (a glial marker) and anti-neurofilament (a neuronal marker), yielded positive staining in most cells, suggesting their possible identity as neural stem cells. Furthermore, Sox 2, a marker for neural stem cells, could be detected from these cell extracts as well as proliferating cell nuclear antigen, a marker for proliferating cells. SBB-W1 could be transfected using pEGFP-N1 indicating their viability and suitability as convenient models for neurophysiological or neurotoxicological studies. 相似文献
555.
556.
Calistri A Del Vecchio C Salata C Celestino M Celegato M Göttlinger H Palù G Parolin C 《Journal of cellular physiology》2009,218(1):175-182
RNA-enveloped viruses bud from infected cells by exploiting the multivesicular body (MVB) pathway. In this context, ubiquitination of structural viral proteins and their direct interaction with cellular factors involved in the MVB biogenesis through short proline rich regions, named late domains (L-domains), are crucial mechanisms. Here we report that, in contrast with the human immunodeficiency virus (HIV), the feline immunodeficiency virus (FIV), a non-primate lentivirus, is strictly dependent for its budding on a "PSAP"-type L-domain, mapping in the carboxy-terminal region of Gag, irrespective of a functional viral protease. Moreover, we provide evidence that FIV egress is related to Gag ubiquitination, that is, linked to the presence of an active L-domain. Finally, although FIV Gag does not contain a PPxY motif, we show that the Nedd4-2s ubiquitin ligase enhances FIV Gag ubiquitination and it is capable to rescue viral mutants lacking a functional L-domain. In conclusion, our data bring to light peculiar aspects of FIV egress, but we also demonstrate that a non-primate lentivirus shares with HIV-1 a novel mechanism of connection to the cellular budding machinery. 相似文献
557.
Graziano Fiorito Andrea Affuso David B. Anderson Jennifer Basil Laure Bonnaud Giovanni Botta Alison Cole Livia D’Angelo Paolo De Girolamo Ngaire Dennison Ludovic Dickel Anna Di Cosmo Carlo Di Cristo Camino Gestal Rute Fonseca Frank Grasso Tore Kristiansen Michael Kuba Fulvio Maffucci Arianna Manciocco Felix Christopher Mark Daniela Melillo Daniel Osorio Anna Palumbo Kerry Perkins Giovanna Ponte Marcello Raspa Nadav Shashar Jane Smith David Smith António Sykes Roger Villanueva Nathan Tublitz Letizia Zullo Paul Andrews 《Invertebrate neuroscience : IN》2014,14(1):13-36
Cephalopods have been utilised in neuroscience research for more than 100 years particularly because of their phenotypic plasticity, complex and centralised nervous system, tractability for studies of learning and cellular mechanisms of memory (e.g. long-term potentiation) and anatomical features facilitating physiological studies (e.g. squid giant axon and synapse). On 1 January 2013, research using any of the about 700 extant species of “live cephalopods” became regulated within the European Union by Directive 2010/63/EU on the “Protection of Animals used for Scientific Purposes”, giving cephalopods the same EU legal protection as previously afforded only to vertebrates. The Directive has a number of implications, particularly for neuroscience research. These include: (1) projects will need justification, authorisation from local competent authorities, and be subject to review including a harm-benefit assessment and adherence to the 3Rs principles (Replacement, Refinement and Reduction). (2) To support project evaluation and compliance with the new EU law, guidelines specific to cephalopods will need to be developed, covering capture, transport, handling, housing, care, maintenance, health monitoring, humane anaesthesia, analgesia and euthanasia. (3) Objective criteria need to be developed to identify signs of pain, suffering, distress and lasting harm particularly in the context of their induction by an experimental procedure. Despite diversity of views existing on some of these topics, this paper reviews the above topics and describes the approaches being taken by the cephalopod research community (represented by the authorship) to produce “guidelines” and the potential contribution of neuroscience research to cephalopod welfare. 相似文献
558.
Pietro Carlozzi Cristina Pintucci Raffaella Piccardi Arianna Buccioni Sara Minieri Maurizio Lambardi 《Biotechnology letters》2010,32(4):477-481
Rhodopseudomonas palustris was grown under continuous irradiances of 36, 56, 75, 151, 320, 500, and 803 W m−2, for a co-production of both bio-H2 and biodiesel (lipids) using fed-batch conditions. The highest overall bio-H2 produced [4.2 l(H2) lculture
−1] was achieved at 320 W m−2, while the highest dry biomass (3.18 g l−1) was attained at 500 W m−2. Dry biomass contained between 22 and 39% lipid. The total energy conversion efficiency was at its highest (6.9%) at 36 W m−2. 相似文献
559.
Eleonora Salvolini Monia Orciani Arianna Vignini Roberto Di Primio Laura Mazzanti 《Cellular & molecular biology letters》2009,14(3):457-465
Recent reports have indicated that, as well as having antiresorptive effects, bisphosphonates could have an application as anti-inflammatory drugs. Our aim was to investigate whether this anti-inflammatory action could be mediated by the nitric oxide (NO) released by the leukocytes migrating to the site of inflammation. In particular, we investigated in vitro the intracellular calcium concentration ([Ca2+]i), the level of NO released by PMN and platelets, and the PMN myeloperoxidase activity after incubation with disodium pamidronate, since there was a postulated modulatory effect of this aminosubstituted bisphosphonate on leukocytes both in vitro and in vivo. Our data shows that the pamidronate treatment provoked a significant increase in the [Ca2+]i parallel to the enhancement in NO release, suggesting a possible activation of constitutive nitric oxide synthase, while the myeloperoxidase activity was significantly reduced. In conclusion, we hypothesized that treatment with pamidronate could stimulate NO-production by cells present near the bone compartment, thus constituting a protective mechanism against bone resorption occurring during inflammation. In addition, PMN- and platelet-derived NO could act as a negative feed-back signal to restrict the inflammatory processes. 相似文献
560.