No abstract

A fast, sensitive, and reliable RP-HPLC method involving cyberlab HPLC System with PDA detection was developed and validated for the quantification of Aclidinium bromide and Formoterol fumarate in inhalation preparations. Chromatography was performed on the Inertsil -ODS C18 (250 x 4.6mm, 5μ) column using filtered and mixed degassed methanol: buffer (75:25 v/v) as a mobile phase with a flow rate of 1.0mL/min and the column effluent was monitored at 240nm. Retention times for Aclidinium bromide 4.713min and Formoterol fumarate 6.691min. The method obeyed linearity in the concentration range of 20-80µg/mL for the two drugs when validated according to standard procedures.

Psychoacoustic and speech perception measures were compared for a group who were exposed to noise regularly through listening to music via personal music players (PMP) and a control group without such exposure. Lifetime noise exposure, quantified using the NESI questionnaire, averaged ten times higher for the exposed group than for the control group. Audiometric thresholds were similar for the two groups over the conventional frequency range up to 8 kHz, but for higher frequencies, the exposed group had higher thresholds than the control group. Amplitude modulation detection (AMD) thresholds were measured using a 4000-Hz sinusoidal carrier presented in threshold-equalizing noise at 30, 60, and 90 dB sound pressure level (SPL) for modulation frequencies of 8, 16, 32, and 64 Hz. At 90 dB SPL but not at the lower levels, AMD thresholds were significantly higher (worse) for the exposed than for the control group, especially for low modulation frequencies. The exposed group required significantly higher signal-to-noise ratios than the control group to understand sentences in noise. Otoacoustic emissions did not differ for the two groups. It is concluded that listening to music via PMP can have subtle deleterious effects on speech perception, AM detection, and hearing sensitivity over the extended high-frequency range.