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Background and purpose: Telestroke has grown significantly since its implementation. Despite growing utilization, there is a paucity of data regarding the diagnostic accuracy of telestroke to distinguish between stroke and its mimics. We aimed to evaluate diagnostic accuracy of telestroke consultations and explore the characteristics of misdiagnosed patients with a focus on stroke mimics. Methods: We conducted a retrospective study of all the consultations in our Ochsner Health's TeleStroke program seen between April 2015 and April 2016. Consultations were classified into one of three diagnostic categories: stroke/transient ischemic attack, mimic, and uncertain. Initial telestroke diagnosis was compared with the final diagnosis post review of all emergency department and hospital data. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR-) for diagnosis of stroke/TIA versus mimic were calculated. Area under receiver-operating characteristic curve (AUC) analysis to predict true stroke was performed. Bivariate analysis based on the diagnostic categories examined association with sex, age, NIHSS, stroke risk factors, tPA given, bleeding after tPA, symptom onset to last known normal, symptom onset to consult, timing in the day, and consult duration. Logistic regression was performed as indicated by bivariate analysis. Results: Eight hundred and seventy-four telestroke evaluations were included in our analysis. Accurate diagnosis through teleneurological consultation was seen in 85% of which 532 were strokes (true positives) and 170 were mimics (true negatives). Sensitivity, specificity, PPV, NPV were 97.8, 82.5, 93.7 and 93.4%, respectively. LR+ and LR- were 5.6 and 0.03. AUC (95% CI) was 0.9016 (0.8749-0.9283). Stroke mimics were more common with younger age and female gender and in those with less vascular risk factors. LR revealed OR (95% CI) of misdiagnosis for female gender of 1.9 (1.3-2.9). Lower age and lower NIHSS score were other predictors of misdiagnosis. Conclusion: We report high diagnostic accuracy of the Ochsner Telestroke Program in discriminating stroke/TIA and stroke mimics, with slight tendency towards over diagnosis of stroke. Female gender, younger age and lower NIHSS score were associated with misdiagnosis.
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Recent literature supports the efficacy and efficiency of telemedicine in improving various health outcomes despite the wide variability in results. Understanding site-specific issues in the implementation of telemedicine trials for broader replication and generalizability of results is needed. Lessons can be learned from existing trials, and a blueprint can guide researchers to conduct these challenging studies using telemedicine more efficiently and effectively. This viewpoint presents relevant challenges and solutions for conducting multisite telemedicine trials using 7 ongoing and completed studies funded by the Patient-Centered Outcomes Research Institute portfolio of large multisite trials to highlight the challenges in implementing telemedicine trials. Critical issues of ensuring leadership and buy-in, appropriate funding, and diverse and representative trials are identified and described, as well as challenges related to clinical, informatics, regulatory, legal, quality, and billing. The lessons learned from these studies were used to create a blueprint of key aspects to consider for the design and implementation of multisite telemedicine trials.
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Telemedicina , Ensaios Clínicos como Assunto/métodos , Humanos , Estudos Longitudinais , Estudos Multicêntricos como Assunto/métodos , PesquisadoresRESUMO
Exosomes (EXs) are cell-derived vesicles that mediate cell-cell communication and could serve as biomarkers. Here we described novel methods for purification and phenotyping of EXs released from endothelial cells (ECs) and endothelial progenitor cells (EPCs) by combining microbeads and fluorescence quantum dots (Q-dots®) techniques. EXs from the culture medium of ECs and EPCs were isolated and detected with cell-specific antibody conjugated microbeads and second antibody conjugated Q-dots by using nanoparticle tracking analysis (NTA) system. The sensitivities of the cell origin markers for ECs (CD105, CD144) and EPCs (CD34, KDR) were evaluated. The sensitivity and specificity were determined by using positive and negative markers for EXs (CD63), platelets (CD41), erythrocytes (CD235a), and microvesicles (Annexin V). Moreover, the methods were further validated in particle-free plasma and patient samples. Results showed that anti-CD105/anti-CD144 and anti-CD34/anti-KDR had the highest sensitivity and specificity for isolating and detecting EC-EXs and EPC-EXs, respectively. The methods had the overall recovery rate of over 70% and were able to detect the dynamical changes of circulating EC-EXs and EPC-EXs in acute ischemic stroke. In conclusion, we have developed sensitive and specific microbeads/Q-dots fluorescence NTA methods for EC-EX and EPC-EX isolation and detection, which will facilitate the functional study and biomarker discovery.
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Accurate analysis of specific microvesicles (MVs) from biofluids is critical and challenging. Here we described novel methods to purify and detect MVs shed from endothelial cells (ECs) and endothelial progenitor cells (EPCs) by combining microbeads with fluorescence quantum dots (Q-dots) coupled nanoparticle tracking analysis (NTA). In the in vitro screening systems, we demonstrated that 1) anti-CD105 (EC marker) and anti-CD34 (EPC marker) conjugated-microbeads had the highest sensitivity and specificity for isolating respective MVs, which were confirmed with negative controls, CD41 and CD235a; 2) anti-CD144 (EC marker) and anti-KDR (EPC marker) conjugated-Q-dots exhibited the best sensitivity and specificity for their respective MV NTA detection, which were confirmed with positive control, anti-Annexin V (MV universal marker). The methods were further validated by their ability to efficiently recover the known amount of EC-MVs and EPC-MVs from particle-depleted plasma, and to detect the dynamical changes of plasma MVs in ischemic stroke patients, as compared with traditional flow cytometry. These novel methods provide ideal approaches for functional analysis and biomarker discovery of ECs- and EPCs- derived MVs.
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Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/metabolismo , Células Progenitoras Endoteliais/metabolismo , Microesferas , Nanopartículas , Pontos Quânticos , Biomarcadores , Micropartículas Derivadas de Células/ultraestrutura , Células Cultivadas , Citometria de Fluxo , Humanos , Nanopartículas/ultraestruturaRESUMO
PURPOSE: A case of topiramate-induced myoclonus and acute psychosis in a patient taking the recommended dosage of topiramate for migraine prophylaxis is reported. SUMMARY: A 29-year-old Caucasian, wheelchair-bound woman with diplegic cerebral palsy and a history of migraines was admitted to the hospital after developing paranoid thoughts and episodes of myoclonus two weeks after an increase in her topiramate dosage (25 mg twice daily to 50 mg twice daily). Her physical examination upon admission was unremarkable, with the exception of a temperature of 38.2 degrees C. Diagnostic laboratory test values, including those of the cerebrospinal fluid, were within normal limits. During neurologic examination, arm jerking, lip smacking, and finger movements occurred spontaneously and unprovoked, and severe bilateral leg myoclonus with plantar stimulation was observed. The results of an ultrasound of her lower extremities and a computed tomography scan of the brain with and without contrast revealed no abnormalities. An electroencephalogram was taken and showed nothing unusual. After nonpharmacologic etiologies were ruled out, her topiramate dosage was decreased and discontinued over four days. Her mental status and myoclonus drastically improved. She was stable and discharged within 24 hours of topiramate discontinuation. Follow-up at six months revealed that her myoclonus had completely resolved. While she has experienced additional psychotic episodes, these were mild and appear to be related to her depression. Myoclonus has not returned. CONCLUSION: A patient with cerebral palsy experienced myoclonus and acute psychosis after receiving a standard dosage of topiramate for migraine prophylaxis.