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Background: Social media are currently considered as a potential complementary source of knowledge for drug safety surveillance. Our primary objective was to estimate the frequency of adverse drug reactions (ADRs) experienced by Twitter users. Our secondary objective was to determine whether tweets constitute a valuable and informative source of data for pharmacovigilance purposes, despite limitations on character number per tweet.

Research design and methods: We selected a list of 33 drugs subject to careful monitoring due to safety concern in France and Europe, and extracted tweets using the streaming API from 30 September 2014 to 5 April 2015. Two pharmacovigilance centers classified these tweets manually as potential ADR case reports.

Results: Among 10,534 tweets, 848 (8.05%) implied or mentioned an ADR without meeting the four FDA criteria required for reporting an ADR, and 289 (2.74%) tweets were classified as ‘case reports.’ Among them 20 (7.27%) tweets mentioned an unexpected ADR and 33 (11.42%) tweets mentioned a serious ADR.

Conclusions: With the use of dedicated tools, Twitter could become a complementary source of information for pharmacovigilance, despite a major limitation regarding causality assessment of ADRs in individual tweets, which may improve with the new limitation to 280 characters per tweet.  相似文献   

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Introduction: Patients with cancer are subject to the cardiotoxic effects of cancer therapy and as more patients survive cancer due to improved treatment they are exposed to various forms of cardiovascular (CV) disease as they age, and vice-versa. Such an interplay of age with both malignancy and CV disease may contribute to increased morbidity and mortality.

Areas covered: This two-part review considers the effects of cancer drug treatment on the CV system. In Part I, the various types of CV and cardiometabolic toxicity of anti-cancer drugs and the possible mechanisms involved are discussed. Also, among the specific oncologic agents, the CV effects of the classical agents and of the large molecule immunological agents (monoclonal antibodies, including immune checkpoint inhibitors) are detailed.

Expert opinion: Oncologic agents produce a variety of CV adverse effects, including cardiomyopathy and heart failure, peri-myocarditis, coronary artery disease, peripheral vascular disease, hypertension (HTN), cardiac arrhythmias, valvular heart disease, and pulmonary HTN. Both the oncologist and the cardiologist need to be aware of such adverse effects and of the specific agents that produce them. They need to join forces to prevent, anticipate, recognize, and manage such complications.  相似文献   

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Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Most patients have pathogenic autoantibodies against the acetylcholine receptor (AChR). In the last years a novel subpopulation of MG patients has been described that harbors antibodies against low-density lipoprotein receptor-related protein 4 (Lrp4), another postsynaptic neuromuscular antigen. In early-onset AChR MG (EOMG), the thymus plays an important role in immunopathogenesis, and early thymectomy is beneficial. It is still unknown if the thymus plays any role in Lrp4-MG. In this pilot study, we compared thymus samples from four patients with Lrp4-MG (one pre-treated with immunosuppressive drugs), four non-MG controls and five EOMG patients (not pretreated with immunosuppressive drugs). Immunohistochemistry of the Lrp4-MG thymi revealed normal architecture, with normal numbers and distribution of B-cells, lymphoid follicles and Hassall's corpuscles. Primary CD23+ lymphoid follicles were similarly infrequent in Lrp4-MG and control thymic sections. In none of the control or Lrp4-MG thymi did we find secondary follicles with CD10+ germinal centers. These were evident in 2 of the 5 EOMG thymi, where primary lymphoid follicles were also more frequent on average, thus showing considerable heterogeneity between patients. Even if characteristic pathological thymic changes were not observed in the Lrp4 subgroup, we cannot exclude a role for the thymus in Lrp4-MG pathogenesis, since one Lrp4-MG patient went into clinical remission after thymectomy alone (at one year follow-up) and one more improved after thymectomy in combination with immunosuppressive therapy.  相似文献   
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Over the past few years, myositis-specific autoantibodies played an increasing role in the inflammatory idiopathic myositis definition. They became the critical immunological marker for immune-mediated necrotizing myopathy diagnosis (IMNM) since the paradigm switch from histological to serological criteria.This review is focused on the key role of the anti-signal recognition particle (anti-SRP) and the anti-3-Hydroxy-3-MethylGlutaryl-Coenzyme A Reductase (anti-HMGCR) antibodies in immune-mediated necrotizing myopathy.Anti-SRP and anti-HMGCR antibodies are robust diagnostic tools in case of both the classical subacute form and the slowly progressive form of IMNM that may mimic muscular dystrophy. Anti-SRP and anti-HMGCR patients share clinical, biological and histological features with some antibody-associated specificity. Anti-SRP patients harbour more severe muscle weakness and atrophy with severe muscle damage on magnetic resonance imaging study. Approximately 10–20% of anti-SRP patients develop extramuscular symptoms, especially lung interstitial disease. Conversely, anti-HMGCR patients are often associated with statin exposure. In both cases, patients have a poor outcome with frequent relapse and the use of combined immunotherapy. Of note, various data suggest a direct pathogenic role of these antibodies reinforcing the interest in targeted therapeutic strategy.  相似文献   
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The aim of this paper is to state what the college teacher's performance should be today in and from the first class of the course (first honnour class) as a contrast to what it was a few years ago and that still persists to a great extent. It begins by insisting on the need to share the epistemological conceptions of different terms such as learning, teaching, etc. between teachers and students; continue with the recommendation that the teacher must be strategic, analyzing also the role of the student and its strategic load and the lightness with which the competences are handled. Next, the learning guide is analyzed and constructive alignment is recommended in its elaboration, then the parts or sectors of the same are described and the paper finalizes indicating the strategic in the teaching performance.  相似文献   
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