Selenium and nitrogen co-doped carbon dots with highly efficient electrochemiluminescence for ultrasensitive detection of microRNA.

In this work, selenium and nitrogen co-doped carbon dots (SeN-CDs) possessing highly efficient electrochemiluminescence (ECL) and excellent biocompatibility were synthesized as a new emitter with S2O82- as a coreactant for constructing a biosensor to detect microRNA-221 (miRNA-221) sensitively. Notably, the SeN-CDs exhibited superior ECL performance compared with the N-doped CDs, in which selenium with excellent redox activity served as a coreaction accelerator for facilitating the electroreduction of S2O82- to significantly improve ECL efficiency. Furthermore, target-induced T7 exonuclease (T7 Exo)-assisted double cycle amplification strategy could convert traces of target miRNA-221 into large amounts of output DNA to capture three-dimensional (3D) nanostructures (DTN-Au NPs-DOX-Fc) loaded with large amounts of ECL signal quencher. The constructed biosensor could realize ultrasensitive detection of miRNA-221 and has a low detection limit reaching 2.3 aM, with a successful application to detect miRNA-221 in lysate of Hela and MHCC97-L cancer cell. This work explored a novel method to strengthen the ECL performance of CDs to construct an ECL biosensing platform with sensitive detecting of biomarkers and disease diagnosis.

Safety and efficacy of nebulized racemic epinephrine in conjunction with oral dexamethasone and mist in the outpatient treatment of croup.

STUDY OBJECTIVE: To identify patients with croup who after treatment with nebulized racemic epinephrine, oral dexamethasone, and mist may be safely discharged home after a period of observation. DESIGN: Prospective interventional. SETTING: Urban children's hospital emergency department. PARTICIPANTS: Children with croup who received racemic epinephrine for the treatment of stridor at rest. INTERVENTIONS: After treatment with .5 mL racemic epinephrine, .6 mg/kg dexamethasone PO, and mist, patients who were assessed as being safe for discharge after 3 hours of observation were discharged home and contacted for 48-hour follow-up. RESULTS: Fifty-five patients with croup were treated with racemic epinephrine. Thirty patients (55%) had sustained responses and were discharged home after 3 hours of observation. No recurrence of respiratory distress and no return visits for medical care were reported (95% confidence interval, 0% to 8.0%). CONCLUSION: Patients with croup who are treated with racemic epinephrine, oral dexamethasone, and mist may be safely discharged home if the patient is assessed as ready for discharge after 3 hours of observation.

Radiographic tracheal diameter measurements in acute infectious croup: an objective scoring system.

The percentage of change in tracheal diameter (TD% change), as assessed by an objective radiological measurement, was used along with a simple subjective clinical score to assess response to therapy in upper airway obstruction in 14 patients with acute infectious croup. Studies were performed on the 14 patients, each of whom was randomly assigned to one of two treatment groups: distilled water or racemic epinephrine (RE), both being nebulized and delivered by manual IPPB. The objective radiological assessment and the subjective clinical score both confirmed that RE is significantly (p less than 0.005) more effective than distilled water in the acute relief of upper airway obstruction. The more precise radiological assessment may be of value in determining objectively better drug therapy for infectious croup.