Non prescribed sale of antibiotics in Riyadh, Saudi Arabia: A Cross Sectional Study

Background Antibiotics sales without medical prescriptions are increasingly recognized as sources of antimicrobial misuse that can exacerbate the global burden of antibiotic resistance. We aimed to determine the percentage of pharmacies who sell antibiotics without medical prescriptions, examining the potential associated risks of such practice in Riyadh, Saudi Arabia, by simulation of different clinical scenarios. Methods A cross sectional study of a quasi-random sample of pharmacies stratified by the five regions of Riyadh. Each pharmacy was visited once by two investigators who simulated having a relative with a specific clinical illness (sore throat, acute bronchitis, otitis media, acute sinusitis, diarrhea, and urinary tract infection (UTI) in childbearing aged women). Results A total of 327 pharmacies were visited. Antibiotics were dispensed without a medical prescription in 244 (77.6%) of 327, of which 231 (95%) were dispensed without a patient request. Simulated cases of sore throat and diarrhea resulted in an antibiotic being dispensed in (90%) of encounters, followed by UTI (75%), acute bronchitis (73%), otitis media (51%) and acute sinusitis (40%). Metronidazole (89%) and ciprofloxacin (86%) were commonly given for diarrhea and UTI, respectively, whereas amoxicillin/clavulanate was dispensed (51%) for the other simulated cases. None of the pharmacists asked about antibiotic allergy history or provided information about drug interactions. Only 23% asked about pregnancy status when dispensing antibiotics for UTI-simulated cases. Conclusions We observed that an antibiotic could be obtained in Riyadh without a medical prescription or an evidence-based indication with associated potential clinical risks. Strict enforcement and adherence to existing regulations are warranted

Growth and carcass characteristics of male dairy calves on a yeast culture-supplemented diet

This experiment was carried out to study the effect of the inclusion of a yeast culture in the diet of feeder dairy calves on their growth and carcass characteristics. Thirty male Friesian calves were randomly allocated to two groups of 15 each (treatment and control). The calves were fed a total mixed ration for a period of 294 days and then slaughtered to obtain carcass measurements. The yeast culture was added to the diet of the treatment group at a level of 20 kg yeast culture/ton of feed. The addition of the yeast culture did not affect final weight, average gain or average daily gain, but reduced total and daily dry matter intakes. Feed conversion ratio was not affected by treatment. Yeast culture supplementation had no effect on fasting weight or cold carcass weight, dressing percentage nor on non-carcass components. Differences in back-fat thickness and in the weight and percentage of carcass cuts were not significant between treatments. Similarly, carcass characteristics and quality measures did not show any significant differences between treatments. In this experiment the inclusion of a yeast culture in the finishing off diet of dairy calves had no effect on their growth rate, feed conversion ratio, carcass characteristics or meat quality. Keywords: Yeast, dairy calves, growth performance, carcass qualitySouth African Journal of Animal Science Vol. 38 (3) 2008: pp. 174-18

PIV study of the effect of piston position on the in-cylinder swirling flow during the scavenging process in large two-stroke marine diesel engines

A simplified model of a low speed large two- stroke marine diesel engine cylinder is developed. The effect of piston position on the in-cylinder swirling flow during the scavenging process is studied using the stereo- scopic particle image velocimetry technique. The mea- surements are conducted at different cross-sectional planes along the cylinder length and at piston positions covering the air intake port by 0, 25, 50 and 75 %. When the intake port is fully open, the tangential velocity profile is similar to a Burgers vortex, whereas the axial velocity has a wake- like profile. Due to internal wall friction, the swirl decays downstream, and the size of the vortex core increases. For increasing port closures, the tangential velocity profile changes from a Burgers vortex to a forced vortex, and the axial velocity changes correspondingly from a wake-like profile to a jet-like profile. For piston position with 75 % intake port closure, the jet-like axial velocity profile at a cross-sectional plane close to the intake port changes back to a wake-like profile at the adjacent downstream cross-sectional plane. This is characteristic of a vortex breakdown. The non-dimensional velocity profiles show no significant variation with the variation in Reynolds number

Design and optimization of gastro-retentive microballoons for enhanced bioavailability of cinnarizine

This study is focused on the design of gastro-retentive drug delivery system composed of hollow microspheres (microballoons) for the sustained delivery of cinnarizine (CIN). The microballoons (MBs) were prepared by the emulsion solvent diffusion method using cellulose acetate butyrate (CAB) as the hosting polymer and absolute ethanol (ETH) and dichloromethane (DCM) as solvents. A 33 full factorial experimental design was adopted to study the effect of different variables and to find an optimum formula with desired properties. Prepared microballoons showed high drug loading capacities and controlled release behaviour. The optimum formulation was chosen on the basis of achieving maximum values for both drug loading capacity and release efficiency as well as having suitable size. The optimized MB (MB-F21) was composed of 200 mg CIN and 400 mg CAB with a DCM/ETH ratio of 2:1. Scanning electron microscopy for the optimum formulation showed a spherical outline with internal porous structure. An in vivo study using human volunteers was performed by determination of CIN concentration in the plasma using the liquid chromatography-mass spectrometry (LC-MS) method. Results proved the superiority of the designed formulation over the market product Stuval® tablets in bioavailability parameters comprising T max as well as area under the plasma CIN concentration-time curve (AUC0–24 h) and AUC0–∞ values. Also, the significantly greater value of mean residence time (MRT) in case of MB-F21 indicates its higher gastric residence time and proves the advantages of micro-multiparticulate dosage forms over conventional one