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Continuous erythropoietin receptor activator (CERA) is a third-generation erythropoiesis-stimulating agent that was developed for the treatment of anemia. However, misuse of CERA for doping in endurance sports has been reported. Previous studies have shown blood as the matrix of choice for the detection of CERA, due to its high molecular weight. The use of dried blood spots (DBSs) for anti-doping purposes constitutes a complementary approach to the standard urine and venous blood matrices and could facilitate sample collection and increase the number of blood samples available for analysis due to reduced costs of sample collection and transport. Here, we investigated whether CERA could be indirectly detected in extracts of single DBSs using an erythropoietin-specific immunoassay that is capable of providing results within approximately 2 h. Reconstituted DBS samples were prepared from mixtures of red blood cell pellets and serum samples. The samples were collected in a previous clinical study in which six healthy volunteers were injected with a single, 200 μg dose of CERA. Using a commercially available ELISA kit, CERA was detected in the DBSs with a detection window of up to 20 days post-injection. Furthermore, in order to demonstrate the fitness-for-purpose, three authentic doping control serum samples, which were identified as containing CERA, were analyzed by the presented methodological approach on DBS. The testing procedure described here could be used as a fast and cost-effective method for the detection of CERA abuse in sport.  相似文献   
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Chronic cannabis use can be associated with uncontrollable vomiting and abdominal pain. Diagnostic criteria for cannabinoid hyperemesis syndrome (CHS) were defined in 2012 by Simonetto et al. The objectives of this study were to describe the prevalence of CHS, the patients' epidemiological characteristics, and to show the difficulties encountered in caring for these patients in emergency departments, the extent of health care and an unsuitable follow‐up in general practices. A prospective cohort of patients with CHS was recruited among a target population of patients leaving the adult emergency services of the Marseille hospitals Nord and La Timone between October 2017 and July 2018, with abdominal pain syndrome of unidentified etiology. Inclusion criteria for the CHS cohort were chronic cannabis use associated with nausea and vomiting. There were 48 patients included in the CHS cohort who took cannabis daily, in a target population of 2 848 patients (i.e. 1.6%). A hot shower was the most effective symptomatic treatment in 54.2% of cases. Patients suffering from CHS spent significantly more hours in emergency departments (11 vs. 6.5), and, on average, visits were more frequent (4.9 vs. 3). 20.3% of them were hospitalized to continue pain medication. Once out of hospital, follow‐up was limited, and weaning off cannabis, the only etiological treatment, was difficult to set up. Informing patients about CHS is essential, and a hot shower could be systematically proposed, thus limiting an unnecessary extent of health care. CHS is genuine, medical staff should be made aware of it in occupational training, and it should be seriously considered in health policies.  相似文献   
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Background Context

Red flags are questions typically ascertained by providers to screen for serious underlying spinal pathologies. The utility of patient-reported red flags in guiding clinical decision-making for spine care, however, has not been studied.

Purpose

The aim of this study was to quantify the sensitivity and specificity of patient-reported red flags in predicting the presence of serious spinal pathologies.

Study Design

This was a retrospective nested case-control study.

Patient Sample

This study consisted of 120 patients with International Classification of Diseases, Ninth Revision, Clinical Modification codes for spinal pathologies and 380 randomly selected patients, from a population of 4,313 patients seen at a large tertiary care spine clinic between October 9, 2013 and June 30, 2014.

Outcome Measures

The presence of patient-reported red flags and red flags obtained from medical records was verified for chart review. The spinal pathology (ie, malignancy, fractures, infections, or cauda equina syndrome) was noted for each patient.

Methods

The sensitivity and specificity of patient-reported red flags for detecting serious spinal pathologies were calculated from data obtained from the 500 patients. Youden's J was used to rank performance. Agreement between patient-reported red flags and those obtained from medical record review was assessed via Cohen's kappa statistic.

Results

“History of cancer” was the best performing patient-reported red flag to identify malignancy (sensitivity=0.75 [95% confidence intervals, CI 0.53–0.90], specificity=0.79 [95% CI 0.75–0.82]). The best performing patient-reported red flag for fractures was the presence of at least one of the following: “Osteoporosis,” “Steroid use,” and “Trauma” (sensitivity=0.59 [95% CI 0.44–0.72], specificity=0.65 [95% CI 0.60–0.69]). The prevalence of infection and cauda equina diagnoses was insufficient to gauge sensitivity and specificity. Red flags from medical records had better performance than patient-reported red flags. There was poor agreement between patient red flags and those obtained from medical record review.

Conclusions

Patient-reported red flags had low sensitivity and specificity for identification of serious pathologies. They should not be used in insolation to make treatment decisions, although they may be useful to prompt further probing to determine if additional investigation is warranted.  相似文献   
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