2,514 research outputs found
Extended-release niacin increases anti-apolipoprotein A-I antibodies that block the antioxidant effect of high-density lipoprotein-cholesterol: the EXPLORE clinical trial.
Extended-release niacin (ERN) is the most effective agent for increasing high-density lipoprotein-cholesterol (HDL-C). Having previously identified anti-HDL antibodies, we investigated whether ERN affected the antioxidant capacity of HDL and whether ERN was associated with the production of antibodies against HDL (aHDL) and apolipoprotein A-I (aApoA-I).
METHODS:
Twenty-one patients older than 18 years, with HDL-C ≤40 mg dl-1 (men) or ≤50 mg dl-1 (women) were randomly assigned to receive daily ERN (n = 10) or placebo (n = 11) for two sequential 12-week periods, with 4 weeks of wash-out before cross-over. Primary outcome was change of paraoxonase-1 (PON1) activity and secondary outcomes were changes in aHDL and aApoA-I antibodies. Clinical Trial Unique Identifier: EudraCT 2006-006889-42.
RESULTS:
The effect of ERN on PON1 activity was nonsignificant (coefficient estimate 20.83 U l-1 , 95% confidence interval [CI] -9.88 to 51.53; P = 0.184). ERN was associated with an increase in HDL-C levels (coefficient estimate 5.21 mg dl-1 , 95% CI 1.16 to 9.25; P = 0.012) and its subclasses HDL2 (coefficient estimate 2.46 mg dl-1 , 95% CI 0.57 to 4.34; P = 0.011) and HDL3 (coefficient estimate 2.73 mg dl-1 , 95% CI 0.47 to 4.98; P = 0.018). ERN was significantly associated with the production of aApoA-I antibodies (coefficient estimate 0.25 μg ml-1 , 95% CI 0.09-0.40; P = 0.001). aApoA-I titres at baseline were correlated with decreased PON activity.
CONCLUSIONS:
The rise in HDL-C achieved with ERN was not matched by improved antioxidant capacity, eventually hampered by the emergence of aApoA-I antibodies. These results may explain why Niacin and other lipid lowering agents fail to reduce cardiovascular risk.info:eu-repo/semantics/publishedVersio
Recommended from our members
Brief survey on computational solutions for Bayesian inference
In this paper, we present a brief review of research work attempting to tackle the issue of tractability in Bayesian inference, including an analysis of the applicability and trade-offs of each proposed solution. In recent years, the Bayesian approach has become increasingly popular, endowing autonomous systems with the ability to deal with uncertainty and incompleteness. However, these systems are also expected to be efficient, while Bayesian inference in general is known to be an NP-hard problem, making it paramount to develop approaches dealing with this complexity in order to allow the implementation of usable Bayesian solutions. Novel computational paradigms and also major developments in massively parallel computation technologies, such as multi-core processors, GPUs and FPGAs, provide us with an inkling of the roadmap in Bayesian computation for upcoming years
Changes in Iron Metabolism Induced by Anti-Interleukin-6 Receptor Monoclonal Antibody are Associated with an Increased Risk of Infection
(1) Background: Treatment of patients with rheumatoid arthritis (RA) with an anti-IL-6 receptor (anti-IL-6R) monoclonal antibody (tocilizumab) has been found to influence iron metabolism. The objective of the present study was to ascertain whether changes in iron metabolism induced by anti-IL-6R biologic therapy were independently associated with an increased infection risk. (2) Methods: A prospective longitudinal study of patients with RA treated with tocilizumab was conducted. RA patients treated with an antitumor necrosis factor α monoclonal antibody were also included as a control group. The primary outcome was occurrence of infection during the first 24 months of biologic therapy. (3) Results: A total of 15 patients were included, with a mean age of 51.0 ± 4,1 and 73.3% (n = 11) female. A multivariate survival regression model, adjusted for confounding factors, was fitted for each of the iron metabolism variables. Hazard ratios for being above the median of each parameter was considered. Transferrin saturation above the median value (>32.1%) was associated with a higher infection risk (HR 4.3; 95%CI 1.0-19.69; p = 0.05). Similarly, although non-significantly, higher serum iron was strongly associated with infection occurrence. (4) Conclusions: This study identified a probable association between infection risk and higher serum iron and transferrin saturation in patients with RA on anti-IL-6R biologic therapy. We suggest that both these parameters should be considered relevant contributing factors for infection occurrence in patients on anti-IL-6R therapy.info:eu-repo/semantics/publishedVersio
Impact of Rubin Observatory Cadence Choices on Supernovae Photometric Classification
The Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) will discover an unprecedented number of supernovae (SNe), making spectroscopic classification for all the events infeasible. LSST will thus rely on photometric classification, whose accuracy depends on the not-yet-finalized LSST observing strategy. In this work, we analyze the impact of cadence choices on classification performance using simulated multiband light curves. First, we simulate SNe with an LSST baseline cadence, a nonrolling cadence, and a presto-color cadence, which observes each sky location three times per night instead of twice. Each simulated data set includes a spectroscopically confirmed training set, which we augment to be representative of the test set as part of the classification pipeline. Then we use the photometric transient classification library snmachine to build classifiers. We find that the active region of the rolling cadence used in the baseline observing strategy yields a 25% improvement in classification performance relative to the background region. This improvement in performance in the actively rolling region is also associated with an increase of up to a factor of 2.7 in the number of cosmologically useful Type Ia SNe relative to the background region. However, adding a third visit per night as implemented in presto-color degrades classification performance due to more irregularly sampled light curves. Overall, our results establish desiderata on the observing cadence related to classification of full SNe light curves, which in turn impacts photometric SNe cosmology with LSST
Oxidative/nitrative stress in the pathogenesis of systemic sclerosis: are antioxidants beneficial?
Systemic sclerosis (SSc) is a multisystem autoimmune disease: characterised from the clinical side by progressive vasculopathy and fibrosis of the skin and different organs and from the biochemical side by fibroblast deregulation with excessive production of collagen and increased expression of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4). The latter contributes to an overproduction of reactive oxygen species that through an autocrine loop maintains NOX4 in a state of activation. Reactive oxygen and nitrogen species are implicated in the origin and perpetuation of several clinical manifestations of SSc having vascular damage in common; attempts to dampen oxidative and nitrative stress through different agents with antioxidant properties have not translated into a sustained clinical benefit. Objective of this narrative review is to describe the origin and clinical implications of oxidative and nitrative stress in SSc, with particular focus on the central role of NOX4 and its interactions, to re-evaluate the antioxidant approaches so far used to limit disease progression, to appraise the complexity of antioxidant treatment and to touch on novel pathways elements of which may represent specific treatment targets in the not so distant future.info:eu-repo/semantics/publishedVersio
Seed and Seedling Anatomy in Euterpe oleraceae Mart. during the Germination Process
peer reviewe
Non-tumor necrosis factor-based biologic therapies for rheumatoid arthritis: present, future, and insights into pathogenesis.
Therapeutic options for patients suffering from the more severe forms of spondyloarthritis have been rather limited in the last decades. There is now accumulating evidence that antitumor necrosis factor therapy is highly effective in spondyloarthritis, especially in ankylosing spondylitis and psoriatic arthritis. Based on the data recently published on more than 500 patients with ankylosing spondylitis and psoriatic arthritis, this treatment seems to be even more effective than in rheumatoid arthritis. The antitumor necrosis factor-alpha agents currently available, infliximab (Remicade), etanercept (Enbrel), and adalimumab (Humira), are approved for the treatment of rheumatoid arthritis in the United States and partly in Europe. The situation in spondyloarthritis is different from that of rheumatoid arthritis because there is an unmet medical need, especially in ankylosing spondylitis: no therapies with disease-modifying antirheumatic drugs are available for severely affected patients, especially with spinal disease. Thus, tumor necrosis factor blockers may even be considered a first-line treatment in a patient with active ankylosing spondylitis and psoriatic arthritis whose condition is not sufficiently controlled with nonsteroidal antiinflammatory drugs in the case of axial disease, and sulfasalazine or methotrexate in the case of peripheral arthritis. For infliximab, a dose of 5 mg/kg was required, and intervals between 6 and 12 weeks were necessary to suppress disease activity constantly-also a major aim for long-term treatment. The standard dosage of etanercept is 2 x 25 mg subcutaneously per week. There are no studies yet on adalimumab (standard rheumatoid arthritis dose, 20-40 mg subcutaneously every 1-2 weeks) in spondyloarthritis. Infliximab was very recently approved for AS in Europe. The efficacy of etanercept was first demonstrated in psoriatic arthritis, and it is now approved for this indication. A double-blind study has also been performed in ankylosing spondylitis, with similarly clear efficacy. There is preliminary evidence that both agents do also work in other spondyloarthritis, such as undifferentiated spondyloarthritis. Ideally, both agents will be approved soon for the short-term treatment of severe, uncontrolled spondyloarthritis. In parallel, studies should be performed to document the long-term efficacy of this treatment. There is hope that ankylosis may be preventable, but it remains to be shown whether patients benefit from long-term antitumor necrosis factor therapy and whether radiologic progression and ankylosis can be stopped. Severe adverse events have remained rare. Complicated infections including tuberculosis have been reported. These can be largely prevented by appropriate screening. At it stands now, the benefits of antitumor necrosis factor therapy in ankylosing spondylitis seem to outweigh these shortcomings
Connective tissue disease-associated interstitial lung disease
BACKGROUND:
Connective tissue diseases (CTD) are frequently associated with interstitial lung disease (ILD), significantly impacting their morbidity and mortality.
AIM:
Analyze the experience of an autoimmune specialized unit on treating CTD-ILD and characterize the population based on most frequent diseases, imaging patterns, lung function tests results, serology and treatment. Assess mortality and mortality predictors in these patients.
METHODS:
Retrospective, descriptive and statistical analysis of the CTD-ILD patients followed up at an autoimmune diseases unit during a 6-year period.
RESULTS:
Over the study period, 75 patients with CTD-ILD were treated with a mean follow-up of 49 ± 31 months. The most frequent CTD were systemic sclerosis and rheumatoid arthritis. ILD was diagnosed prior to CTD in 8% of patients and concomitantly in 35%. Nonspecific interstitial pneumonia was the CT pattern in 60% and 35% had an isolated diminished DLCO on lung function tests. Pulmonary hypertension was present in 12% and it was the single most important mortality predictor (OR 14.41, p = 0.006). Corticosteroids are the mainstay of treatment but biologics were prescribed in 39% of the patients (mostly tocilizumab and rituximab). Two scleroderma patients were recently treated with nintedanib.
CONCLUSIONS:
ILD is a potential complication of every CTD and can impose a dramatic burden on these patients. The clinical relevance of ILD together with their early expression in the course of the disease underlines the importance of the presence of chest physicians in these units.info:eu-repo/semantics/publishedVersio
Major acute splenic sequestration crisis in an adult patient with sickle-cell disease
A crise de retenção esplénica é uma complicação, frequentemente, fatal da drepanocitose. É rara em adultos, pela elevada
incidência de autoesplenectomia durante a infância. Heterozigóticos com traços de drepanocitose e de beta-talassémia têm
fenótipos menos graves, podendo manter um baço funcional até à idade adulta. Descrevemos um caso de crise de retenção
esplénica num homem de 19 anos, com concentração mÃnima de hemoglobina de 2,9g/dL, que resolveu após esplenectomia
emergente. Os poucos casos descritos na literatura acarretam uma mortalidade elevada. Um diagnóstico rápido e actuação
imediata são necessários para garantir a sobrevivência. É apresentada uma revisão da fisiopatologia e da abordagem terapêutica desta entidade
- …