55 research outputs found

    Study design and rationale for the Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study (OCEAN(a)-DOSE).

    Get PDF
    BACKGROUND Data support lipoprotein(a) (Lp[Lp(a)]) being a risk factor for atherosclerotic cardiovascular disease (ASCVD). Olpasiran is a small interfering RNA molecule that markedly reduces Lp(a) production in hepatocytes. STUDY DESIGN The Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study is a multicenter, randomized, double-blind, placebo-controlled dose-finding study in 281 subjects with established ASCVD and Lp(a) > 150 nmol/L. Patients were randomly allocated to one of 4 active subcutaneous doses of olpasiran (10 mg q12 weeks, 75 mg q12 weeks, 225 mg q 12 weeks, or 225 mg q24 weeks) or matched placebo. The primary objective is to evaluate the effects of olpasiran dosed every 12 weeks compared with placebo on the percent change in Lp(a) from baseline at 36 weeks. Enrollment is now complete and follow-up is ongoing. CONCLUSIONS OCEAN(a)-DOSE trial is assessing the Lp(a)-lowering efficacy and safety of olpasiran. These data will be used to determine optimal dosing and design for a cardiovascular outcomes trial

    Antithrombotic Treatment in Transcatheter Aortic Valve Implantation Insights for Cerebrovascular and Bleeding Events

    Get PDF
    Transcatheter aortic valve implantation (TAVI) has emerged as a therapeutic alternative for patients with symptomatic aortic stenosis at high or prohibitive surgical risk. However, patients undergoing TAVI are also at high risk for both bleeding and stroke complications, and specific mechanical aspects of the procedure itself can increase the risk of these complications. The mechanisms of periprocedural bleeding complications seem to relate mainly to vascular/access site complications (related to the use of large catheters in a very old and frail elderly population), whereas the pathophysiology of cerebrovascular events remains largely unknown. Further, although mechanical complications, especially the interaction between the valve prosthesis and the native aortic valve, may play a major role in events that occur during TAVI, post-procedural events might also be related to a prothrombotic environment or state generated by the implanted valve, the occurrence of atrial arrhythmias, and associated comorbidities. Antithrombotic therapy in the setting of TAVI has been empirically determined, and unfractionated heparin during the procedure followed by dual antiplatelet therapy with aspirin (indefinitely) and clopidogrel (1 to 6 months) is the most commonly recommended treatment. However, bleeding and cerebrovascular events are common; these may be modifiable with optimization of periprocedural and post-procedural pharmacology. Further, as the field of antiplatelet and anticoagulant therapy evolves, potential drug combinations will multiply, introducing variability in treatment. Randomized trials are the best path forward to determine the balance between the efficacy and risks of antithrombotic treatment in this high risk-population

    Variability of Individual Platelet Reactivity Over Time in Patients Treated With Clopidogrel Insights From the ELEVATE–TIMI 56 Trial

    Get PDF
    AbstractBackgroundThe degree of antiplatelet response to clopidogrel has been associated with clinical outcomes. Studies have investigated whether adjustment of antiplatelet therapies based on a single platelet function test is beneficial.ObjectivesThe aim of the study was to test the stability of platelet reactivity measurements over time among patients treated with standard and double doses of clopidogrel.MethodsThe ELEVATE–TIMI 56 (Escalating Clopidogrel by Involving a Genetic Strategy–Thrombolysis In Myocardial Infarction 56) investigators genotyped 333 patients with coronary artery disease and randomized them to various clopidogrel regimens. Patients with at least 2 platelet function results on the same maintenance dose of clopidogrel (75 mg or 150 mg) were analyzed. Platelet aggregation was measured using P2Y12 reaction units (PRU).ResultsIn total, the mean platelet reactivity and the total number of nonresponders (PRU ≥230) with clopidogrel did not change between 2 periods for the 75-mg (22.4% vs. 21.9%; p = 0.86) and 150-mg doses of clopidogrel (11.5% vs. 11.5%; p = 1.00). In contrast, when evaluating each patient individually, 15.7% of patients taking clopidogrel 75 mg and 11.4% of patients taking 150 mg had a change in their responder status when tested at 2 different time points (p < 0.001). Despite being treated with the same dose of clopidogrel, >40% of patients had a change in PRU >40 on serial sampling, which approximates the average PRU difference caused by increasing the clopidogrel dose from 75 mg to 150 mg.ConclusionsMeasurements of platelet reactivity vary over time in a significant proportion of patients. Thus, treatment adjustment according to platelet function testing at a single time point might not be sufficient for guiding antiplatelet therapy in clinical or research settings. (Escalating Clopidogrel by Involving a Genetic Strategy–Thrombolysis In Myocardial Infarction 56 [ELEVATE–TIMI 56]; NCT01235351

    Proteomic analysis of pollination-induced corolla senescence in petunia

    Get PDF
    Senescence represents the last phase of petal development during which macromolecules and organelles are degraded and nutrients are recycled to developing tissues. To understand better the post-transcriptional changes regulating petal senescence, a proteomic approach was used to profile protein changes during the senescence of Petunia×hybrida ‘Mitchell Diploid’ corollas. Total soluble proteins were extracted from unpollinated petunia corollas at 0, 24, 48, and 72 h after flower opening and at 24, 48, and 72 h after pollination. Two-dimensional gel electrophoresis (2-DE) was used to identify proteins that were differentially expressed in non-senescing (unpollinated) and senescing (pollinated) corollas, and image analysis was used to determine which proteins were up- or down-regulated by the experimentally determined cut-off of 2.1-fold for P <0.05. One hundred and thirty-three differentially expressed protein spots were selected for sequencing. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to determine the identity of these proteins. Searching translated EST databases and the NCBI non-redundant protein database, it was possible to assign a putative identification to greater than 90% of these proteins. Many of the senescence up-regulated proteins were putatively involved in defence and stress responses or macromolecule catabolism. Some proteins, not previously characterized during flower senescence, were identified, including an orthologue of the tomato abscisic acid stress ripening protein 4 (ASR4). Gene expression patterns did not always correlate with protein expression, confirming that both proteomic and genomic approaches will be required to obtain a detailed understanding of the regulation of petal senescence

    Delivery of maternal health care in Indigenous primary care services: baseline data for an ongoing quality improvement initiative

    Get PDF
    Extent: 10p.BACKGROUND: Australia's Aboriginal and Torres Strait Islander (Indigenous) populations have disproportionately high rates of adverse perinatal outcomes relative to other Australians. Poorer access to good quality maternal health care is a key driver of this disparity. The aim of this study was to describe patterns of delivery of maternity care and service gaps in primary care services in Australian Indigenous communities. METHODS: We undertook a cross-sectional baseline audit for a quality improvement intervention. Medical records of 535 women from 34 Indigenous community health centres in five regions (Top End of Northern Territory 13, Central Australia 2, Far West New South Wales 6, Western Australia 9, and North Queensland 4) were audited. The main outcome measures included: adherence to recommended protocols and procedures in the antenatal and postnatal periods including: clinical, laboratory and ultrasound investigations; screening for gestational diabetes and Group B Streptococcus; brief intervention/advice on health-related behaviours and risks; and follow up of identified health problems. RESULTS: The proportion of women presenting for their first antenatal visit in the first trimester ranged from 34% to 49% between regions; consequently, documentation of care early in pregnancy was poor. Overall, documentation of routine antenatal investigations and brief interventions/advice regarding health behaviours varied, and generally indicated that these services were underutilised. For example, 46% of known smokers received smoking cessation advice/counselling; 52% of all women received antenatal education and 51% had investigation for gestational diabetes. Overall, there was relatively good documentation of follow up of identified problems related to hypertension or diabetes, with over 70% of identified women being referred to a GP/Obstetrician. CONCLUSION: Participating services had both strengths and weaknesses in the delivery of maternal health care. Increasing access to evidence-based screening and health information (most notably around smoking cessation) were consistently identified as opportunities for improvement across services.Alice R. Rumbold, Ross S. Bailie, Damin Si, Michelle C. Dowden, Catherine M. Kennedy, Rhonda J. Cox, Lynette O’Donoghue, Helen E. Liddle, Ru K. Kwedza, Sandra C. Thompson, Hugh P. Burke, Alex D. H. Brown, Tarun Weeramanthri and Christine M. Connor

    Developing Consensus-Based Priority Outcome Domains for Trials in Kidney Transplantation:A Multinational Delphi Survey With Patients, Caregivers, and Health Professionals

    Get PDF
    Background: Inconsistencies in outcome reporting and frequent omission of patient-centered outcomes can diminish the value of trials in treatment decision-making. We identified critically important outcome domains in kidney transplantation based on the shared priorities of patients/caregivers and health professionals. Methods: In a 3-round Delphi survey, patients/caregivers and health professionals rated the importance of outcome domains for trials in kidney transplantation on a 9-point Likert scale and provided comments. During Round 2 and 3, participants re-rated the outcomes after reviewing their own score, the distribution of the respondents’ scores, and comments. We calculated the median, mean, and proportion rating 7-9 (critically important), and analyzed comments thematically. Results: 1018 participants (461 [45%] patients/caregivers and 557 [55%] health professionals) from 79 countries completed Round 1, and 779 (77%) completed Round 3. The top eight outcomes that met the consensus criteria in Round 3 (mean ≥7.5, median ≥8 and proportion >85%) in both groups were graft loss, graft function, chronic rejection, acute rejection, mortality, infection, cancer (excluding skin) and cardiovascular disease. Compared with health professionals, patients/caregivers gave higher priority to six outcomes (mean difference of 0.5 or more): skin cancer, surgical complications, cognition, blood pressure, depression, and ability to work. We identified five themes: capacity to control and inevitability, personal relevance, debilitating repercussions, gaining awareness of risks, and addressing knowledge gaps. Conclusions: Graft complications and severe comorbidities were critically important for both stakeholder groups. These stakeholder-prioritized outcomes will inform the core outcome set to improve the consistency and relevance of trials in kidney transplantation

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

    Get PDF
    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

    The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

    Get PDF
    Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients
    corecore