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Introduction: Polymyalgia rheumatica (PMR), a common disease in individuals older than 50 in the western world, is characterized by bilateral inflammatory pain involving the shoulder girdle and less commonly the neck and pelvic girdle. The main goals of the currently available treatment are to induce remission and prevent relapse.

Areas covered: This review briefly presents the main epidemiological and clinical features of PMR and discusses in depth both its classical management as well as new therapies used in PMR.

Expert opinion: In general, patients with isolated PMR experience a rapid response (in less than seven days) to 12.5–25 mg/prednisone/day. Methotrexate is the conventional disease-modifying antirheumatic drug most commonly used for disease management, especially for relapses of the disease. However, this agent often yields a modest effect. Randomized controlled trials do not support the use of antitumor necrosis factor agents in PMR. Several case series and retrospective studies have highlighted the efficacy of the anti-interleukin-6 receptor antibody tocilizumab in PMR. However, controlled trials are needed to fully establish the efficacy of this biologic agent in PMR. The potential beneficial effect of the Janus-kinase inhibitors remains to be determined.  相似文献   

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Arginine-rich protein motifs have been described as potent cell-penetrating peptides (CPPs) but also as rather specific ligands of the cell surface chemokine receptor CXCR4, involved in the infection by the human immunodeficiency virus (HIV). Polyarginines are commonly used to functionalize nanoscale vehicles for gene therapy and drug delivery, aimed to enhance cell penetrability of the therapeutic cargo. However, under which conditions these peptides do act as either unspecific or specific ligands is unknown. We have here explored the cell penetrability of differently charged polyarginines in two alternative presentations, namely as unassembled fusion proteins or assembled in multimeric protein nanoparticles. By this, we have observed that arginine-rich peptides switch between receptor-mediated and receptor-independent mechanisms of cell penetration. The relative weight of these activities is determined by the electrostatic charge of the construct and the oligomerization status of the nanoscale material, both regulatable by conventional protein engineering approaches.  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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Resident physicians are continually exposed to fatigue, which can lead to work, academic and personal problems, so it is important to have reliable and valid instruments to measure it. One of the most used is Fatigue Severity Scale, but, there are versions with different number of items in different populations. Therefore, the purpose of this work was to translate, adapt culturally relevant and compare versions with different numbers of items, to identify the most appropriate in Mexican resident physicians. With three different groups of participants; first one for translation by seven expert judges in the language, second for psychometric validation with 100 resident physicians, and third for confirmatory factor analysis and invariance test by type of program (specialty and high specialty) with 182 resident physicians. Distribution, discrimination, reliability and factor structure of the scale were tested in an exploratory and confirmatory analysis, leaving a final scale of 6 items with good fit (X2[9] = 9,39, p = 0,40; CFI = 0,99; RMSEA = 0,02), with a reliability = 0,91 and strict factorial invariance by type of residence program.  相似文献   
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