160 research outputs found

    Systems biology of platelet-vessel wall interactions

    Get PDF
    Platelets are small, anucleated cells that participate in primary hemostasis by forming a hemostatic plug at the site of a blood vessel's breach, preventing blood loss. However, hemostatic events can lead to excessive thrombosis, resulting in life-threatening strokes, emboli, or infarction. Development of multi-scale models coupling processes at several scales and running predictive model simulations on powerful computer clusters can help interdisciplinary groups of researchers to suggest and test new patient-specific treatment strategies

    Enhanced mGluR1 function causes motor deficits and region-specific Purkinje cell dysfunction

    Get PDF
    Spinocerebellar ataxias (SCAs) are autosomal dominantly inherited neurodegenerative disorders with no effective treatment. Aberrant signalling through the metabotropic glutamate receptor (mGluR1) has been implicated in several SCAs. However, whether disease is caused through decreased or increased mGluR1 signalling remains controversial. Here, we generate the first mouse model of enhanced mGluR1 function by introducing a gain-of-function mutation (p.Y792C) that causes SCA44 in the metabotropic glutamate receptor 1 (Grm1) gene. Grm1 mutant mice recapitulate key pathophysiological aspects of SCA, including progressive motor deficits, altered climbing fibre innervation and perturbed Purkinje cell spontaneous activity. We report that changes in synaptic innervation and intrinsic Purkinje cell activity upon overactive mGluR1 signalling manifest in a lobule- and disease-stage-specific manner. Our findings demonstrate that enhanced mGluR1 function is a direct and specific driver of Purkinje cell dysfunction and pathology and provide a mechanism for understanding the selective vulnerability of different Purkinje cell populations in SCA.

    Long-Term Safety, Tolerability and Survival in Patients with Pulmonary Arterial Hypertension Treated with Macitentan: Results from the SERAPHIN Open-Label Extension

    Get PDF
    Introduction: In SERAPHIN, a long-term, event-driven, double-blind randomised controlled trial in pulmonary arterial hypertension (PAH), macitentan 10 mg significantly reduced the risk of morbidity/mortality compared with placebo. Its open-label extension study (SERAPHIN OL) further assessed long-term safety and tolerability of macitentan 10 mg in PAH patients. Methods: Patients in SERAPHIN who completed the double-blind treatment period or experienced a morbidity event during the study could enter SERAPHIN OL. Patients received macitentan 10 mg once daily, and safety and survival were assessed until end of treatment (+ 28 days). Two overlapping sets were analysed for safety: (1) all patients in SERAPHIN OL (OL safety set); (2) patients randomised to macitentan 10 mg in SERAPHIN (long-term safety/survival set). Survival was evaluated as an exploratory endpoint in the latter set. Results: Of 742 patients randomised in SERAPHIN, 550 (74.1%) entered SERAPHIN OL (OL safety set); 242 patients were randomised to macitentan 10 mg in SERAPHIN (long-term safety/survival set). Median (min, max) exposure to macitentan 10 mg was 40.1 (0.1, 130.5) months (2074.7 patient-years; OL safety set) and 54.7 (0.1, 141.3) months (1151.0 patient-years; long-term safety/survival set). Safety in both analysis sets was comparable to the known safety profile of macitentan. Kaplan-Meier survival estimates (95% CI) at 1, 5, 7 and 9 years were 95.0% (91.3, 97.1), 73.3% (66.6, 78.9), 62.6% (54.6, 69.6) and 52.7% (43.6, 61.0), respectively (long-term safety/survival set; median follow-up: 5.9 years). Conclusions: This analysis provides the longest follow-up for safety and survival published to date for any PAH therapy. The safety profile of macitentan 10 mg over this extensive treatment period was in line with that observed in SERAPHIN. As the majority of patients were receiving other PAH therapy at macitentan initiation, our study provides additional insight into the long-term safety of macitentan, including as part of combination therapy. Trial Registration: ClinicalTrials.gov Identifiers: NCT00660179 and NCT00667823

    Interaction of amisulpride with GLUT1 at the blood-brain barrier. Relevance to Alzheimer’s disease

    Get PDF
    Blood-brain barrier (BBB) dysfunction may be involved in the increased sensitivity of Alzheimer's disease (AD) patients to antipsychotics, including amisulpride. Studies indicate that antipsychotics interact with facilitated glucose transporters (GLUT), including GLUT1, and that GLUT1 BBB expression decreases in AD. We tested the hypotheses that amisulpride (charge: +1) interacts with GLUT1, and that BBB transport of amisulpride is compromised in AD. GLUT1 substrates, GLUT1 inhibitors and GLUT-interacting antipsychotics were identified by literature review and their physicochemical characteristics summarised. Interactions between amisulpride and GLUT1 were studied using in silico approaches and the human cerebral endothelial cell line, hCMEC/D3. Brain distribution of [3H]amisulpride was determined using in situ perfusion in wild type (WT) and 5xFamilial AD (5xFAD) mice. With transmission electron microscopy (TEM) we investigated brain capillary degeneration in WT mice, 5xFAD mice and human samples. Western blots determined BBB transporter expression in mouse and human. Literature review revealed that, although D-glucose has no charge, charged molecules can interact with GLUT1. GLUT1 substrates are smaller (184.95±6.45g/mol) than inhibitors (325.50±14.40g/mol) and GLUT-interacting antipsychotics (369.38±16.04). Molecular docking showed beta-D-glucose (free energy binding: -15.39kcal/mol) and amisulpride (-29.04kcal/mol) interact with GLUT1. Amisulpride did not affect [14C]D-glucose hCMEC/D3 accumulation. [3H]amisulpride uptake into the brain (except supernatant) of 5xFAD mice compared to WT remained unchanged. TEM revealed brain capillary degeneration in human AD. There was no difference in GLUT1 or P-glycoprotein BBB expression between WT and 5xFAD mice. In contrast, caudate P-glycoprotein, but not GLUT1, expression was decreased in human AD capillaries versus controls. This study provides new details about the BBB transport of amisulpride, evidence that amisulpride interacts with GLUT1 and that BBB transporter expression is altered in AD. This suggests that antipsychotics could potentially exacerbate the cerebral hypometabolism in AD. Further research into the mechanism of amisulpride transport by GLUT1 is important for improving antipsychotics safety

    European Registry on Helicobacter pylori management (Hp-EuReg): Patterns and trends in first-line empirical eradication prescription and outcomes of 5 years and 21 533 patients

    Get PDF
    Objective The best approach for Helicobacter pylori management remains unclear. An audit process is essential to ensure clinical practice is aligned with best standards of care. Design International multicentre prospective non-interventional registry starting in 2013 aimed to evaluate the decisions and outcomes in H. pylori management by European gastroenterologists. Patients were registered in an e-CRF by AEG-REDCap. Variables included demographics, previous eradication attempts, prescribed treatment, adverse events and outcomes. Data monitoring was performed to ensure data quality. Time-trend and geographical analyses were performed. Results 30 394 patients from 27 European countries were evaluated and 21 533 (78%) first-line empirical H. pylori treatments were included for analysis. Pretreatment resistance rates were 23% to clarithromycin, 32% to metronidazole and 13% to both. Triple therapy with amoxicillin and clarithromycin was most commonly prescribed (39%), achieving 81.5% modified intention-to-treat eradication rate. Over 90% eradication was obtained only with 10-day bismuth quadruple or 14-day concomitant treatments. Longer treatment duration, higher acid inhibition and compliance were associated with higher eradication rates. Time-trend analysis showed a region-dependent shift in prescriptions including abandoning triple therapies, using higher acid-inhibition and longer treatments, which was associated with an overall effectiveness increase (84%-90%). Conclusion Management of H. pylori infection by European gastroenterologists is heterogeneous, suboptimal and discrepant with current recommendations. Only quadruple therapies lasting at least 10 days are able to achieve over 90% eradication rates. European recommendations are being slowly and heterogeneously incorporated into routine clinical practice, which was associated with a corresponding increase in effectiveness

    Analysis of Clinical Phenotypes through Machine Learning of First-Line H. pylori Treatment in Europe during the Period 2013–2022: Data from the European Registry on H. pylori Management (Hp-EuReg)

    Get PDF
    The segmentation of patients into homogeneous groups could help to improve eradication therapy effectiveness. Our aim was to determine the most important treatment strategies used in Europe, to evaluate first-line treatment effectiveness according to year and country. Data collection: All first-line empirical treatments registered at AEGREDCap in the European Registry on Helicobacter pylori management (Hp-EuReg) from June 2013 to November 2022. A Boruta method determined the “most important” variables related to treatment effectiveness. Data clustering was performed through multi-correspondence analysis of the resulting six most important variables for every year in the 2013–2022 period. Based on 35,852 patients, the average overall treatment effectiveness increased from 87% in 2013 to 93% in 2022. The lowest effectiveness (80%) was obtained in 2016 in cluster #3 encompassing Slovenia, Lithuania, Latvia, and Russia, treated with 7-day triple therapy with amoxicillin–clarithromycin (92% of cases). The highest effectiveness (95%) was achieved in 2022, mostly in Spain (81%), with the bismuth–quadruple therapy, including the single-capsule (64%) and the concomitant treatment with clarithromycin–amoxicillin–metronidazole/tinidazole (34%) with 10 (69%) and 14 (32%) days. Cluster analysis allowed for the identification of patients in homogeneous treatment groups assessing the effectiveness of different first-line treatments depending on therapy scheme, adherence, country, and prescription year

    Comparison of the management of Helicobacter pylori infection between the older and younger European populations

    Get PDF
    The prevalence of Helicobacter pylori remains high in the older population. Specific age-related peculiarities may impact the outcomes of H. pylori treatment. The aim of the study was to evaluate the diagnostics and effectiveness of H. pylori eradication between the younger and older European populations. “European Registry on H. pylori Management (Hp-EuReg)” data from 2013 to 2022 were analyzed. Patients were divided into older (≥ 60 years) and younger (18–59 years) groups. Modified intention-to-treat (mITT) and per-protocol (PP) analysis was performed. 49,461 patients included of which 14,467 (29%) were older-aged. Concomitant medications and penicillin allergy were more frequent among the older patients. Differences between younger and older populations were observed in treatment duration in first-line treatment and in proton pump inhibitors (PPIs) doses in second-line treatment. The overall incidence of adverse events was lower in the older adults group. The overall first-line treatment mITT effectiveness was 88% in younger and 90% in the older patients (p < 0.05). The overall second-line mITT treatment effectiveness was 84% in both groups. The effectiveness of the most frequent first- and second-line triple therapies was suboptimal (< 90%) in both groups. Optimal efficacy (≥ 90%) was achieved by using bismuth and non-bismuth-based quadruple therapies. In conclusion, the approach to the diagnostics and treatment of H. pylori infection did not generally differ between younger and older patients. Main differences were reported in the concurrent medications, allergy to penicillin and adverse events both in first- and second-line treatment. Optimal effectiveness rates were mostly achieved by using bismuth and non-bismuth-based quadruple therapies. No clinically relevant differences in the effectiveness between the age groups were observed

    Role of compliance in Helicobacter pylori eradication treatment: Results of the European Registry on H. pylori management

    Get PDF
    Background: Adherence to Helicobacter pylori (H. pylori) eradication treatment is a cornerstone for achieving adequate treatment efficacy. Objective: To determine which factors influence compliance with treatment. Methods: A systematic prospective non-interventional registry (Hp-EuReg) of the clinical practice of European gastroenterologists. Compliance was considered adequate if ≥90% drug intake. Data were collected until September 2021 using the AEG-REDCap e-CRF and were subjected to quality control. Modified intention-to-treat analyses were performed. Multivariate analysis carried out the factors associated with the effectiveness of treatment and compliance. Results: Compliance was inadequate in 646 (1.7%) of 38,698 patients. The non-compliance rate was higher in patients prescribed longer regimens (10-, 14-days) and rescue treatments, patients with uninvestigated dyspepsia/functional dyspepsia, and patients reporting adverse effects. Prevalence of non-adherence was lower for first-line treatment than for rescue treatment (1.5% vs. 2.2%; p < 0.001). Differences in non-adherence in the three most frequent first-line treatments were shown: 1.1% with proton pump inhibitor + clarithromycin + amoxicillin; 2.3% with proton pump inhibitor clarithromycin amoxicillin metronidazole; and 1.8% with bismuth quadruple therapy. These treatments were significantly more effective in compliant than in non-compliant patients: 86% versus 44%, 90% versus 71%, and 93% versus 64%, respectively (p < 0.001). In the multivariate analysis, the variable most significantly associated with higher effectiveness was adequate compliance (odds ratio, 6.3 [95%CI, 5.2–7.7]; p < 0.001). Conclusions: Compliance with Helicobacter pylori eradication treatment is very good. Factors associated with poor compliance include uninvestigated/functional dyspepsia, rescue-treatment, prolonged treatment regimens, the presence of adverse events, and the use of non-bismuth sequential and concomitant treatment. Adequate treatment compliance was the variable most closely associated with successful eradication
    corecore