Near Real-Time Measurement of Forces Applied by An Optical Trap to A Rigid Cylindrical Object

An automated data acquisition and processing system is established to measure the force applied by an optical trap to an object of unknown composition in real time. Optical traps have been in use for the past 40 years to manipulate microscopic particles, but the magnitude of applied force is often unknown and requires extensive instrument characterization. Measuring or calculating the force applied by an optical trap to nonspherical particles presents additional difficulties which are also overcome with our system. Extensive experiments and measurements using well-characterized objects were performed to verify the system performance

Near Real-Time Measurement of Forces Applied by An Optical Trap to A Rigid Cylindrical Object

An automated data acquisition and processing system is established to measure the force applied by an optical trap to an object of unknown composition in real time. Optical traps have been in use for the past 40 years to manipulate microscopic particles, but the magnitude of applied force is often unknown and requires extensive instrument characterization. Measuring or calculating the force applied by an optical trap to nonspherical particles presents additional difficulties which are also overcome with our system. Extensive experiments and measurements using well-characterized objects were performed to verify the system performance

Comparative In Vitro

Purpose: To compare in vitro susceptibility of amphotericin B (AMB) and amphotericin B methyl ester (AME) (a more soluble and less toxic formulation of AMB) against Candida albicans isolates recovered from human cases of endophthalmitis. Methods: The in vitro susceptibility of AMB and AME was determined for C. albicans isolates recovered from endophthalmitis ( N =10) and for C. albicans ATCC reference strain 90028 using the Clinical and Laboratory Standards Institute M27-A2 (NCCLS/CLSI) broth dilution method. All isolates were obtained from samples of vitreous humor of patients with suspected endophthalmitis within the last 5 years at the Bascom Palmer Eye Institute, University of Miami Miller School of Medicine (Miami, FL). Results: The minimal inhibitory concentrations (MICs) of AME were equal to or lower than values for AMB in 7 of the 10 isolates; range: AME (0.125–1 μg/mL) versus (0.5–1 μg/mL) for AMB. The MIC 90 value of both drugs was equal (1 μg/mL). Compared with AMB, the minimal fungicidal concentrations (MFCs) of AME were equal to or lower in 8 of 10 isolates; range: AME (0.125–2 μg/mL) versus AMB (0.25–4 μg/mL). MFC 90 values of AME (1 μg/mL) was slightly superior to AMB (2 μg/mL). The MIC of the quality control strain (ATCC ® 90028) was within an acceptable range. Conclusions: AME was equivalent to AMB in vitro against C. albicans . This formula may offer a slightly more efficient and less toxic formulation for the treatment of Candida endophthalmitis