Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin following single-dose subcutaneous injection in black-tailed prairie dogs (Cynomys ludovicianus).

OBJECTIVE To determine plasma concentrations of enrofloxacin and its active metabolite ciprofloxacin following single-dose SC administration to black-tailed prairie dogs (Cynomys ludovicianus). ANIMALS 8 captive healthy 6-month-old sexually intact male black-tailed prairie dogs. PROCEDURES Enrofloxacin (20 mg/kg) was administered SC once to 6 prairie dogs and IV once to 2 prairie dogs. A blood sample was collected from each animal immediately before (0 hours) and 0.5, 1, 2, 4, 8, 12, and 24 hours after drug administration to evaluate the pharmacokinetics of enrofloxacin and ciprofloxacin. Plasma enrofloxacin and ciprofloxacin concentrations were quantified with ultraperformance liquid chromatography-mass spectrometry, and noncompartmental pharmacokinetic analysis was performed. RESULTS Enrofloxacin was biotransformed to ciprofloxacin in the prairie dogs used in the study. For total fluoroquinolones (enrofloxacin and ciprofloxacin), the mean (range) of peak plasma concentration, time to maximum plasma concentration, and terminal half-life after SC administration were 4.90 µg/mL (3.44 to 6.08 µg/mL), 1.59 hours (0.5 to 2.00 hours), and 4.63 hours (4.02 to 5.20 hours), respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that administration of enrofloxacin (20 mg/kg, SC, q 24 h) in black-tailed prairie dogs may be appropriate for treatment of infections with bacteria for which the minimum inhibitory concentration of enrofloxacin is ≤ 0.5 µg/mL. However, clinical studies are needed to determine efficacy of such enrofloxacin treatment.

Visual outcome after contact lens and intraocular lens correction of neonatal monocular aphakia in monkeys.

PURPOSE: A monkey model was used to evaluate intraocular lenses (IOLs) and extended-wear contact lenses (EWCLs) for the optical treatment of infantile aphakia in humans. Specifically, the relative effectiveness of EWCLs used alone and IOLs used in combination with EWCLs in preventing amblyopia was assessed. METHODS: A total of 33 rhesus monkeys was studied in this project, 24 assigned to experimental treatment groups and 9 to normal controls. Contact lenses made from a diffusing material or dyed opaque were placed on one eye at birth to simulate an infantile cataract. A unilateral lensectomy was then performed on the same eye within 2.5 weeks after birth. In 15 monkeys this was combined with implantation of an IOL. The eyes were left aphakic in the remaining 9 animals. EWCLs were used to adjust the optical correction of both aphakic and pseudophakic eyes to a near point (3-5 D). Opaque lenses were used to maintain daily part-time (approximately 70%) occlusion of the fellow eye. The primary outcome measure was grating acuity assessed with behavioral methods. Some animals were also assessed for acuity with sweep visually evoked potentials (VEPs) and for optotype acuity (Landolt C) with behavioral methods. RESULTS: Two of the animals with IOLs developed complications in the eye that precluded completion of the behavioral assessment protocol. Only behavioral outcomes obtained before or in the absence of surgical complications are presented. There was a developmental delay in the maturation of grating acuity in both eyes of both treatment groups. Normal adult levels of grating acuity were eventually achieved in the group treated with IOLs combined with EWCLs. Grating acuity was significantly poorer than normal in aphakic eyes treated only with EWCLs. Comparison of the two treatment groups revealed that pseudophakic eyes treated with multifocal IOLs had significantly better gating acuity than aphakic eyes. Assessments of optotype acuity and sweep VEP acuity revealed amblyopic deficits in both pseudophakic and aphakic eyes. CONCLUSIONS: Given an absence of serious postoperative complications, neonatal correction of aphakia with IOLs combined with EWCLs can lead to normal grating acuity in a primate model. Correction with EWCLs alone was not sufficient to produce normal grating acuity. Multifocal IOL treatments combined with EWCL provided a significantly better outcome than EWCL methods alone. However, neither IOL nor EWCL methods were able to prevent amblyopia as evaluated using behavioral testing with optotypes or with sweep VEPs.

Acuity and contrast sensitivity in monkeys after neonatal intraocular lens implantation with and without part-time occlusion of the fellow eye.

PURPOSE: The authors used a monkey model to evaluate intraocular lenses (IOLs) for the treatment of infantile cataract in humans. Specifically, they sought to assess the effectiveness of IOLs, with and without occlusion therapy, in preventing amblyopia. METHODS: A diffuser contact lens was placed on one eye each of 11 neonatal monkeys to simulate an infantile cataract. A unilateral lensectomy, combined with the implantation of an IOL, was performed on the same eye 1 to 2 weeks after birth. Clear contact lenses were used to adjust the optical correction of the pseudophakic eyes to a near point, and opaque lenses were used to maintain daily part-time (70%) occlusion of the fellow eyes of half the subjects. Behavioral methods were used to assess grating acuity, optotype acuity (Landolt C), and contrast sensitivity. RESULTS: In five of the animals, complications that developed in the eye with the implant were severe enough to interfere with visual function. The authors present only behavioral outcomes obtained before or in the absence of surgical complications. In monkeys that underwent daily 70% occlusion, grating acuity in the pseudophakic eyes eventually matured to normal adult levels. Grating acuity was significantly poorer in animals with no occlusion therapy. Even in animals with normal grating acuity, assessments of optotype acuity revealed amblyopic deficits; contrast sensitivity was impaired as well at middle and low spatial frequencies. CONCLUSIONS: The current study demonstrates that if there are no complications secondary to surgery, normal grating acuity can be obtained in neonatal monkey eyes that undergo IOL implantation, optical correction of the pseudophakic eye to a near point, and 70% occlusion of the fellow eye. However, these good outcomes for grating acuity cannot be attained without occlusion therapy. In addition, optotype acuity and sensitivity to contrast always are impaired.

The evolution of the home healthcare industry--developing new levels of business sophistication.

Home healthcare is undergoing significant evolution as it matures as an industry segment. As different types of providers are attracted to home care, home care product companies are finding their customer bases dividing in two--traditional referral customers and a new type of customer, those looking for joint ventures and contracts.