Monitoring of antibiotic resistance in bacteria isolated from laboratory animals / 한국실험동물학회지

The drug resistance of microorganisms isolated from laboratory animals never treated with antibiotics is being reported consistently, while the number of laboratory animals used in medicine, pharmacy, veterinary medicine, agriculture, nutrition, and environmental and health science has increased rapidly in Korea. Therefore, this study examined the development of antimicrobial resistance in bacteria isolated from laboratory animals bred in Korea. A total of 443 isolates (7 species) containing 5 Sphingomonas paucimobilis, 206 Escherichia coli, 60 Staphylococcus aureus, 15 Staphylococcus epidermidis, 77 Enterococcus faecalis, 27 Citrobacter freundii, 35 Acinetobacter baumannii were collected from the nose, intestine, bronchus and reproductive organs of ICR mice and SD rats. Of these species, Acinetobacter baumannii and Enterococcus faecalis showed significant antimicrobial resistance according to the minimum inhibition concentration (MIC) in E-test. In case of Acinetobacter baumannii, several isolates showed MIC values 16-128 microg/mL for cefazolin and cefoxitin, and higher resistance (128-512 microg/mL) to nitrofurantoin than that of standard type. Resistance to cefazolin, cefoxitin and nitrofurantoin was detected in 17.14, 20.00, and 8.57% of the Acinetobacter baumannii isolates, respectively. In addition, 44.1% of the Enterococcus faecalis isolates collected from the laboratory animals were resistant to oxacillin concentration of 16-32 microg/mL range, while MIC value of standard type was below oxacillin concentration of 6 microg/mL. These results suggest that in rodent species of laboratory animals, Acinetobacter baumannii are resistance to cefazolin, cefoxitin and nitrofurantoin, whereas those of Enterococcus faecalis were resistance to oxacillin.

Pneumatic Displacement of Submacular Hemorrhage with Intravitreal Injection of SF6 Gas without Tissue Plasminogen Activator

PURPOSE: To assess the efficacy and safety of intravitreal injection of SF6 gas for the displacement of submacular hemorrhage without use of tissue plasminogen activator (tPA) METHODS: Three hundred microliter of pure SF6 gas 0.3 ml was injected into the vitreous cavity in 9 eyes with submacular hemorrhage involving the fovea because of myopic degeneration (3 eyes), trauma (3 eyes), age-related macular degeneration (2 eyes), macroaneurysm (1 eyes), branch retinal vein occlusion (1 eyes) and myopic degeneration (2 eyes) within 4 weeks after the onset of symptoms. The patients were instructed to maintain a prone position for less than 7 days. RESULTS: Initial visual acuity was ranged from hand motion to 0.2 and visual improvement was found in 7 eyes on the 7th day after the gas injection. On the 7th day after the gas injection, submacular hemorrhage was completely displaced in 2 eyes and slightly displaced with a reduction in the thickness of hemorrhage in 2 eyes. Transient elevation of intraocular pressure occured in 1 eye and was successfully controlled with medications. CONCLUSIONS: Intravitreal SF6 gas injection is simple and can displace submacular hemorrhage without use of tissue plasminogen activator in many cases with no serious complications.

Pattern-VEP in Child Amblyopia

We assessed the potential clinical usefulness of pattern-visual evoked potentials (=PVEP) in the diagnosis of amblyopia. 15 children with bilateral amblyopia, 64 children with unilateral amblyopia and 11 children without amblyopia participated. After estimating of visual acuity for each eye. PVEP were also obtained. Of the 15 bilateral amblyopic children 12 (80%) showed abnormally lower amplitudes than normal children and amplitudes of the rest 3 patients were in normal range and their visual acuity were relatively upper range, 0.5-0.6. Of the 64 unilateral amblyopic children 4 of 9(44.4%) children who had 2 line difference of interocular visual acuity, 2 of 3(67.7%) children who had 3 line difference and all children except 1 who had 4 or more line difference(99.9%) showed abnormal interocular amplitude difference ratio(=IADR). As a result, bilateral and unilateral amblyopia can be identified by PVEP amplitude and IADR and abnormal IADR shows that interocular visual acuity differences is over 3-4 lines. We thought that PVEP could be used to find the amblyopic eye and monitor the effect of treatment in preverbal children also.