Drug utilisation in medical intensive care unit: a retrospective analysis from a tertiary care teaching hospital

Background: The World Health Organisation has defined drug utilization study as “the marketing, distribution, prescription and use of drugs in a society, with special emphasis on the resulting medical, social, and economic consequences. The objective was to evaluate drug utilization pattern in medical intensive care unit (MICU) in a tertiary care teaching hospital.Methods: A retrospective observational study was conducted in MICU for adult patients admitted from October to December 2013. Data collected was analysed for demographics, indication, duration of stay, World Health Organisation (WHO) prescribing indicators including anatomical therapeutic chemical classification and defined daily dose (DDD).Results: A six hundred encounters from 63 male and 44 female patients with a mean age of 60.88±16.87 were studied. Average duration of stay was 5.61±3.88 days. The common indications for admission were dyspnoea 20 (18.69%), upper gastrointestinal bleed 16 (14.95%), cerebrovascular accident 14 (13.08%) and sepsis 13 (12.15%). Total number of drugs prescribed was 246. Total drug encounters were 7695. Average number of drugs per encounter was 12.83. Percentage of drugs prescribed by generic name was 38.21%, 44.7% and 40.65% of the drugs were prescribed from National and WHO essential medicine list respectively. Among the drugs prescribed 65.44%, 32.93% and 17.48% were oral, injectable and fixed dose combination preparations respectively. Percentage of encounters resulting in prescription of an antibiotic and an injection were 59% and 85.83% respectively. The most commonly prescribed drugs were pantoprazole (100%), human regular insulin (52.83%), piperacillin + tazobactam (45%) and ceftriaxone (38%). Their DDD/100 bed days were found to be 83.79, 12.78, 12.50, and 17.81 respectively.Conclusions: Overall the prescribing pattern seems to be rational but may be further strengthened by increasing generic drug prescription, judicious use of pantoprazole and periodic longitudinal surveillance studies

Design, fabrication and application of GaN-based micro-LED arrays with individual addressing by n-electrodes

We demonstrate the development, performance and application of a GaN-based micro-light emitting diode (μLED) array sharing a common p-electrode (anode), and with individually addressable nelectrodes (cathodes). Compared to conventional GaN-based LED arrays, this array design employs a reversed structure of common and individual electrodes, which makes it innovative and compatible with n-type metal-oxide-semiconductor (NMOS) transistor-based drivers for faster modulation. Excellent performance characteristics are illustrated by an example array emitting at 450 nm. At a current density of 17.7 kA/cm2 in direct-current operation, the optical power and small signal electrical-to-optical modulation bandwidth of a single LED element with 24 μm diameter are over 2.0 mW and 440 MHz, respectively. The optimized fabrication process also ensures a high yield of working μLED elements per array, and excellent element-to-element uniformity of electrical/optical characteristics. Results on visible light communication are presented as an application of an array integrated with an NMOS driver. Data transmission at several hundred Mbps without bit error is achieved for single and multiple-μLED-element operations, under an on-off-keying modulation scheme. Transmission of stepped sawtooth waveforms is also demonstrated to confirm that the μLED elements can transmit discrete multi-level signals

Design, fabrication and application of GaN-based micro-LED arrays with individual addressing by n-electrodes

We demonstrate the development, performance and application of a GaN-based micro-light emitting diode (μLED) array sharing a common p-electrode (anode), and with individually addressable nelectrodes (cathodes). Compared to conventional GaN-based LED arrays, this array design employs a reversed structure of common and individual electrodes, which makes it innovative and compatible with n-type metal-oxide-semiconductor (NMOS) transistor-based drivers for faster modulation. Excellent performance characteristics are illustrated by an example array emitting at 450 nm. At a current density of 17.7 kA/cm2 in direct-current operation, the optical power and small signal electrical-to-optical modulation bandwidth of a single LED element with 24 μm diameter are over 2.0 mW and 440 MHz, respectively. The optimized fabrication process also ensures a high yield of working μLED elements per array, and excellent element-to-element uniformity of electrical/optical characteristics. Results on visible light communication are presented as an application of an array integrated with an NMOS driver. Data transmission at several hundred Mbps without bit error is achieved for single and multiple-μLED-element operations, under an on-off-keying modulation scheme. Transmission of stepped sawtooth waveforms is also demonstrated to confirm that the μLED elements can transmit discrete multi-level signals

The Crystal Structure of OprG from Pseudomonas aeruginosa, a Potential Channel for Transport of Hydrophobic Molecules across the Outer Membrane

Background: The outer membrane (OM) of Gram-negative bacteria provides a barrier to the passage of hydrophobic and hydrophilic compounds into the cell. The OM has embedded proteins that serve important functions in signal transduction and in the transport of molecules into the periplasm. The OmpW family of OM proteins, of which P. aeruginosa OprG is a member, is widespread in Gram-negative bacteria. The biological functions of OprG and other OmpW family members are still unclear. Methodology/Principal Findings: In order to obtain more information about possible functions of OmpW family members we have solved the X-ray crystal structure of P. aeruginosa OprG at 2.4 A ˚ resolution. OprG forms an eightstranded b-barrel with a hydrophobic channel that leads from the extracellular surface to a lateral opening in the barrel wall. The OprG barrel is closed off from the periplasm by interacting polar and charged residues on opposite sides of the barrel wall. Conclusions/Significance: The crystal structure, together with recent biochemical data, suggests that OprG and other OmpW family members form channels that mediate the diffusion of small hydrophobic molecules across the OM by a latera

Development, performance and application of novel GaN-based micro-LED arrays with individually addressable n-electrodes

We demonstrate the development, performance and application of a GaN-based micro-light emitting diode array sharing a common p-electrode with individual-addressed n-electrodes. These individually-addressed n-electrodes minimize the series-resistance difference from conductive paths, and offer compatibility with n-type metal-oxide-semiconductor transistor-based drivers for faster modulation