Bilateral Keratoconus in a Patient with Isolated Foveal Hypoplasia

This is a Photo Essay and does not have an abstract

Retracted: Novel NAD‐independent Avibacterium paragallinarum: Isolation, characterization and molecular identification in Iran

Abstract Background Infectious coryza (IC) is an invasive upper respiratory disease caused by Avibacterium paragallinarum that affects birds, particularly chickens. The objective of this study is to isolate, characterize and molecularly identify the bacterium A. paragallinarum in poultry birds, as well as to determine its antibiotic sensitivity and resistance. Methods A total of 10 chickens from four different Iranian farms with typical IC symptoms were used in this study. The nasal swabs were streaked onto chocolate agar plates and blood agar plates and incubated at 37°C in 5% CO2 for 24 to 48 h. As part of the identification of bacteria, bacteriological observations and polymerase chain reaction (PCR) testing are conducted. The antibiotic sensitivity tests were also performed using the disk diffusion method against A. paragallinarum and the prevalence in different farms was determined. Results By using biochemical assays and PCR analyses, seven strains of A. paragallinarum were isolated from samples of four chicken farms with typical IC clinical signs. Most isolates (4/7) showed the typical requirement for nicotinamide adenine dinucleotide (NAD) and an enriched CO2 atmosphere for growth. Three of the seven strains of A. paragallinarum were found to be novel NAD‐independent under anaerobic conditions. There was one biochemical biovar identified in terms of carbohydrate fermentation patterns, although changes in maltose carbohydrate fermentation patterns were detected in the No. 5 strain. All isolates were sensitive to gentamicin and spectinomycin. Three novel NAD‐independent strains (Nos.1, 5 and 7) were found to be multidrug‐resistant (MDR) and resistant to at least three classes of antibiotics. There was greater antibiotic resistance in the three NAD‐independent isolates than in normal NAD‐dependent bacteria. Conclusion By discovering NAD‐independent forms of A. paragallinarum, these species have a greater range than previously believed. A clear, cautious approach should be taken in diagnosing and possibly controlling IC

Design and Evaluation of Delayed-Release Osmotic Capsule of Acetaminophen: Delayed-release osmotic capsule of acetaminophen

Hard gelatin capsule filled with acetaminophen, osmotic agent (sorbitol), a release promoter (sodium dodecyl sulfate), coated with a semipermeable cellulose acetate membrane containing a hydrophobic plasticizer (castor oil) and sealed with white bees wax plug was designed. When placed in the sink water penetrates the membrane, dissolves the osmotic agent and increases the osmotic pressure inside the capsule. The increased osmotic pressure enhances the water imbibition and consequently increases the hydrostatic pressure inside the capsule and when the latter pressure is high enough it expels out the plug and the drug release commences. With cellulose acetate concentration constant in membrane forming solution, 11% (w/w), the factors affecting the onset of the drug release, i.e. the lag time (tL), were thickness of semipermeable membrane (0.033-0.112 mm) and plug thickness (2.40-3.40 mm) although the influence of semipermeable membrane thickness was more important than plug thickness in delaying the onset of release. As the statistical analysis revealed, castor oil concentrations in the range of 3-4% (w/w) did not affect the lag time. With the control of the membrane thickness, the onset of release could be adjusted from 2 to 7 h. The formulations with tL of 3.9 and 5.8 h may have practical benefits in that if such systems are administered simultaneously with conventional forms the 6 and 4 times daily drug dosage frequency would be reduced to 3 and 2 times regimens, respectively. A theoretical justification was provided for the observed nonlinear relationship between the onset and/or tL of drug release and thickness of the semipermeable membrane. After the lag time, the drug release fromthe systems conformed to the USP requirements

Propranolol Hydrochloride Osmotic Capsule with Controlled Onset of Release

Hard gelatin capsule was coated by a cellulose acetate as a semi permeable membrane with or without castor oil and filled with propranolol hydrochloride, and sorbitol as an osmotic agent. After sealing the capsule with white bees wax plug, the onset of release and dissolution rate of the drug were studied. Water penetration into the capsule from the dissolution medium increases simultaneously the osmotic and hydrostatic pressures of its content. When the hydrostatic pressure is high enough to overweigh the gravity and frictional forces of the plug, the expulsion of the plug occurs and drug release starts. The effects of thicknesses of the membrane and plug as well as the concentrations of cellulose acetate and castor oil on the onset of drug release were presented by a polynomial model. It was found that the effect of plug thickness on the onset of release is more important when the membrane is thicker. The results showed that the presence of caster oil in coating formulation (cellulose acetate 10% or 15%) increased the onset of release (to values). The onset of release varied from 0.6 to 10.5 h among which the onset times of 4.2, 4.8, 5.9, 5.5, 7.5, 5.0, 7.8 and 10.5 h could be of use for either chronotherapeutic purposes in protection of patients against heart attacks and strokes during early morning hours or reducing daily frequency of dosage