1,443 research outputs found

    Heparan Sulfate Proteoglycans Mediate the Angiogenic Activity of the Vascular Endothelial Growth Factor Receptor-2 Agonist Gremlin.

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    OBJECTIVE: Heparan sulfate proteoglycans (HSPGs) modulate the interaction of proangiogenic heparin-binding vascular endothelial growth factors (VEGFs) with signaling VEGF receptor-2 (VEGFR2) and neuropilin coreceptors in endothelial cells (ECs). The bone morphogenic protein antagonist gremlin is a proangiogenic ligand of VEGFR2, distinct from canonical VEGFs. Here we investigated the role of HSPGs in VEGFR2 interaction, signaling, and proangiogenic capacity of gremlin in ECs. METHODS AND RESULTS: Surface plasmon resonance demonstrated that gremlin binds heparin and heparan sulfate, but not other glycosaminoglycans, via N-, 2-O, and 6-O-sulfated groups of the polysaccharide. Accordingly, gremlin binds HSPGs of the EC surface and extracellular matrix. Gremlin/HSPG interaction is prevented by free heparin and heparan sulfate digestion or undersulfation following EC treatment with heparinase II or sodium chlorate. However, at variance with canonical heparin-binding VEGFs, gremlin does not interact with neuropilin-1 coreceptor. On the other hand, HSPGs mediate VEGFR2 engagement and autophosphorylation, extracellular signaling-regulated kinase(1/2) and p38 mitogen-activated protein kinase activation, and consequent proangiogenic responses of ECs to gremlin. On this basis, we evaluated the gremlin-antagonist activity of a panel of chemically sulfated derivatives of the Escherichia coli K5 polysaccharide. The results demonstrate that the highly N,O-sulfated derivative K5-N,OS(H) binds gremlin with high potency, thus inhibiting VEGFR2 interaction and angiogenic activity in vitro and in vivo. CONCLUSIONS: HSPGs act as functional gremlin coreceptors in ECs, affecting its productive interaction with VEGFR2 and angiogenic activity. This has allowed the identification of the biotechnological K5-N,OS(H) as a novel angiostatic gremlin antagonist

    Efficacy of adalimumab as second-line therapy in a pediatric cohort of crohn’s disease patients who failed infliximab therapy: The Italian society of pediatric gastroenterology, hepatology, and nutrition experience

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    Background: Adalimumab (Ada) treatment is an available option for pediatric Crohn’s disease (CD) and the published experience as rescue therapy is limited. Objectives: We investigated Ada efficacy in a retrospective, pediatric CD cohort who had failed previous infliximab treatment, with a minimum follow-up of 6 months. Methods: In this multicenter study, data on demographics, clinical activity, growth, laboratory values (CRP) and adverse events were collected from CD patients during follow-up. Clinical remission (CR) and response were defined with Pediatric CD Activity Index (PCDAI) score ≤10 and a decrease in PCDAI score of ≥12.5 from baseline, respectively. Results: A total of 44 patients were consecutively recruited (mean age 14.8 years): 34 of 44 (77%) had active disease (mean PCDAI score 24.5) at the time of Ada administration, with a mean disease duration of 3.4 (range 0.3–11.2) years. At 6, 12, and 18 months, out of the total of the enrolled population, CR rates were 55%, 78%, and 52%, respectively, with a significant decrease in PCDAI scores (P<0.01) and mean CRP values (mean CRP 5.7 and 2.4 mL/dL, respectively; P<0.01) at the end of follow-up. Steroid-free remission rates, considered as the total number of patients in CR who were not using steroids at the end of this study, were 93%, 95%, and 96% in 44 patients at 6, 12, and 18 months, respectively. No significant differences in growth parameters were detected. In univariate analysis of variables related to Ada efficacy, we found that only a disease duration >2 years was negatively correlated with final PCDAI score (P<0.01). Two serious adverse events were recorded: 1 meningitis and 1 medulloblastoma. Conclusion: Our data confirm Ada efficacy in pediatric patients as second-line biological therapy after infliximab failure. Longer-term prospective data are warranted to define general effectiveness and safety in pediatric CD patients

    Acute pain management in children: A survey of Italian pediatricians

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    Background: Current guidelines recommend assessing and relieving pain in all children and in all instances; yet, in clinical practice, management is frequently suboptimal. We investigated the attitude of Italian family pediatricians towards the evaluation and treatment of different types of acute pain in children aged 7-12 years. Methods: This is a cross-sectional study based on a 17-question survey accessible online from October 2017 to October 2018. Responders had to describe cases of children suffering from any type of acute pain among headache, sore throat, musculoskeletal/post-traumatic pain, and earache. Children's characteristics, pain assessment modalities and therapeutic approaches were queried. The following tests were used: Z-proportion to evaluate the distribution of categorical data; chi-squared and Kruskall-Wallis to explore data heterogeneity across groups; Mann-Whitney for head-to-head comparisons. Results: Overall, 929 pediatricians presented 6335 cases uniformly distributed across the types examined. Pain was more frequently of moderate intensity (42.2%, P < 0.001) and short duration (within some days: 98.4%, P < 0.001). Only 50.1% of responders used an algometric scale to measure pain and 60.5% always prescribed a treatment. In children with mild-moderate pain (N = 4438), the most commonly used first-line non-opioids were ibuprofen (53.3%) and acetaminophen (44.4%). Importantly, a non-recommended dosage was prescribed in only 5.3% of acetaminophen-treated cases (overdosing). Among the misconceptions emerged, there were the following: I) ibuprofen and acetaminophen have different efficacy and safety profiles (when choosing the non-opioid, effectiveness weighted more for ibuprofen [79.7% vs 74.3%, P < 0.001] and tolerability for acetaminophen [74.0% vs 55.4%, P < 0.001]); ii) ibuprofen must be taken after meals to prevent gastric toxicities (52.5%); ibuprofen and acetaminophen can be used combined/alternated for persisting mild-moderate pain (16.1%). In case of moderate-severe pain not completely controlled by opioids, ibuprofen and acetaminophen were the most used add-on medications, with ibuprofen being much more prescribed than acetaminophen (65.2% vs 23.7%, respectively) overall and in all pain types. Conclusions: Several gaps exist between the current practice of pain assessment and treatment and recommendations. Further efforts are needed to raise awareness and improve education on the possible exposure of the child to short- A nd long-term consequences in case of suboptimal pain management

    Evidence-based diagnosis and treatment of macrophage activation syndrome in systemic juvenile idiopathic arthritis.

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    Background Macrophage activation syndrome (MAS) is a severe and potentially lethal complication of several inflammatory diseases but seems particularly linked to systemic juvenile idiopathic arthritis (sJIA). Standardized diagnostic and treatment guidelines for MAS in sJIA are currently lacking. The aim of this systematic literature review was to evaluate currently available literature on diagnostic criteria for MAS in sJIA and provide an overview of possible biomarkers for diagnosis, disease activity and treatment response and recent advances in treatment. Methods A systematic literature search was performed in MEDLINE, EMBASE and Cochrane. 495 papers were identified. Potentially relevant papers were selected by 3 authors after which full text screening was performed. All selected papers were evaluated by at least two independent experts for validity and level of evidence according to EULAR guidelines. Results 27 papers were included: 7 on diagnosis, 9 on biomarkers and 11 on treatment. Systematic review of the literature confirmed that there are no validated diagnostic criteria for MAS in sJIA. The preliminary Ravelli criteria, with the addition of ferritin, performed well in a large retrospective case-control study. Recently, an international consortium lead by PRINTO proposed a new set of diagnostic criteria able to distinguish MAS from active sJIA and/or infection with superior performance. Other promising diagnostic biomarkers potentially distinguish MAS complicating sJIA from primary and virus-associated hemophagocytic lymphohistiocytosis. The highest level of evidence for treatment comes from case-series. High dose corticosteroids with or without cyclosporine A were frequently reported as first-line therapy. From the newer treatment modalities, promising responses have been reported with anakinra. Conclusion MAS in sJIA seems to be diagnosed best by the recently proposed PRINTO criteria, although prospective validation is needed. Novel promising biomarkers for sJIA related MAS are in need of prospective validation as well, and are not widely available yet. Currently, treatment of MAS in sJIA relies more on experience than evidence based medicine. Taking into account the severity of MAS and the scarcity of evidence, early expert consultation is recommended as soon as MAS is suspected
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