Locking the GFP Fluorophore to Enhance Its Emission Intensity.

The Green Fluorescent Protein (GFP) and its analogues have been widely used as fluorescent biomarkers in cell biology. Yet, the chromophore responsible for the fluorescence of the GFP is not emissive when isolated in solution, outside the protein environment. The most accepted explanation is that the quenching of the fluorescence results from the rotation of the aryl-alkene bond and from the Z/E isomerization. Over the years, many efforts have been performed to block these torsional rotations, mimicking the environment inside the protein ß-barrel, to restore the emission intensity. Molecule rigidification through chemical modifications or complexation, or through crystallization, is one of the strategies used. This review presents an overview of the strategies developed to achieve highly emissive GFP chromophore by hindering the torsional rotations.

Endobronchial Ultrasound under Moderate Sedation versus General Anesthesia.

BACKGROUND: Different anesthetic protocols may influence endobronchial ultrasound-guided needle aspiration (EBUS-TBNA) outcomes, patient comfort, and even safety. In this study, two anesthesia techniques were assessed and compared for EBUS-TBNA. METHODS: A prospective, multicenter study was carried out. Patients were allocated to Group 1 (general anesthesia with neuromuscular blockade and controlled ventilation) and Group 2 (intravenous sedation). EBUS-TBNA accuracy was the primary outcome. Safety, patient comfort and satisfaction, and operators' difficulties were defined as secondary outcomes. RESULTS: Of the 115 patients enrolled (Group 1 = 59, Group 2 = 56), EBUS-TBNA was performed for hilar or mediastinal lesion diagnosis and lung cancer staging in, respectively, 77 (67%) and 38 (33%) patients. The numbers of lymph nodes stations (1.8 ± 1.0 vs. 1.7 ± 1.0, p = 0.472) and punctures per station (6.9 ± 3.1 vs. 6.0 ± 2.5, p = 0.084) were similar between groups. Adequate samples were obtained from 109 patients (97.3%) with similar diagnostic accuracy. Procedure duration was not significantly different (p = 0.348). Hemodynamic parameters and systolic and diastolic blood pressures were higher in Group 1 at the beginning and at the end of the procedure. Adverse events were equally distributed, and no significant differences were found regarding patient satisfaction and bronchoscopist/anesthesiologist difficulties. CONCLUSIONS: The type of anesthesia used did not influence EBUS-TBNA outcomes. EBUS-TBNA performed under sedation or general anesthesia did not affect the diagnostic yield, complication rate, and patients' comfort and satisfaction.