Pharmacokinetics of topically applied ciprofloxacin in tears of mesocephalic and brachycephalic dogs

OBJECTIVE: To evaluate the pharmacokinetics of ophthalmic ciprofloxacin in the tear film of normal mesocephalic and brachycephalic dogs. ANIMALS STUDIED: Twenty mesocephalic dogs and 15 brachycephalic dogs. PROCEDURES: Thirty-five microliters of ciprofloxacin were placed on the cornea of both eyes of each dog. Five brachycephalic dogs were used twice. A tear-test strip placed in the ventral cul de sac for 30 s was used to obtain samples. The tear film of each eye was sampled once at eight time-points post administration, resulting in five samples at each time-point. Samples were evaluated using high performance liquid chromatography. Data from the two skull types were compared using the unpaired two-tailed t-test. RESULTS: The mean concentration of ciprofloxacin in the tears of mesocephalic dogs was 192.8 +/- 269.97, 140.6 +/- 91.06, 56.60 +/- 28.47, 13.6 +/- 6.3, 43.25 +/- 59.71, 16.6 +/- 10.62, 15.6 +/- 13.16 and 6.25 +/- 9.84 microg/g at 5, 10, 15, 30 min and 1, 2, 4 and 6 h, respectively. The mean concentration of ciprofloxacin in the tears of brachycephalic dogs was 272.6 +/- 106.21, 144.4 +/- 142.32, 131.2 +/- 147.07, 75 +/- 80.07, 40.8 +/- 30.35, 35 +/- 21.98, 52.75 +/- 51.87 and 8.6 +/- 12.10 microg/g at 5, 10, 15, 30 min and 1, 2, 4 and 6 h, respectively. There was no statistical difference in tear concentration at any time-point between skull types. CONCLUSIONS: Topical application of ciprofloxacin resulted in a mean tear concentration of ciprofloxacin that remained above the MIC(90) levels for most pathogenic bacteria for 6 h in normal mesocephalic and brachycephalic dogs.     

Temporal Changes in Cadmium, Thallium, and Vanadium Mobility in Soil and Phytoavailability under Field Conditions

A field study was conducted over a 30 mo period to examine movement of Cd, Tl, and V through the profile of a Coastal Plain soil (Typic Kandiudult) and the availability of these trace metals to bush bean (Phaseolus vulgaris L.) plants. The metals were applied to field plots as dissolved salts and mixed into the surface 7.5 cm. The greatest concentration of all three metals was observed in the surface soils, with a steep decrease occurring down to the 7.5 to 15 cm depth. Thallium was the most mobile of the three metals; approximately 15% of the applied Tl and <3% of the applied Cd and V moved below the surface 7.5-cm region during the 30-mo experiment. Extractable concentrations of all three metals in the surface soils decreased significantly (P ≤0.05) during the initial 18 mo after treatment. No further decrease occurred between 18 and 30 mo. The presence of Al- and Fe-oxides and small amounts of clay minerals and organic matter in this highly-weathered, low cation-exchange soil were likely responsible for the retention of the trace metals. Bioavailability, as measured by concentrations and total amounts of metals in root and aboveground tissues of plants, did not change significantly between 18 and 30 mo. These data suggest that bioavailability of Cd, Tl, and V decreased over time as a result of transformation of these elements into unavailable forms and not to leaching. These changes in bioavailability occurred soon after application, becoming negligible after 18 mo.     

Soil Microbial Communities Reflect both Inherent Soil Properties and Management Practices in Wisconsin Potato Fields

Microbial communities in soils provide numerous functions vital to agricultural productivity, and there is growing interest in understanding and manipulating these communities to achieve more sustainable production systems. We investigated microbial communities in potato fields in Wisconsin to determine the extent to which microbial communities were structured by inherent soil properties versus factors under grower control. We found that soil properties, including texture and chemistry, shaped microbial communities at broad levels, determining the diversity and abundance of phyla. Organic versus conventional management, however, correlated with finer scale differences in microbial communities, while crop variety was not associated with microbial community composition in this study. These results suggest that grower practices have the potential to alter microbial communities, but these effects will take place within an existing soil context. Future research is necessary to determine how these patterns in microbial community structure relate to functional outcomes for plant health.     

Use of mycophenolate mofetil as a rescue agent in the treatment of severe generalized myasthenia gravis in three dogs

Objective – To describe the use of IV and oral mycophenolate mofetil (MMF) as adjunctive therapy in 3 dogs with severe generalized myasthenia gravis.
Case Series Summary – Three dogs suffering from severe generalized myasthenia gravis as confirmed by acetylcholine antibody titers were treated with MMF as part of their treatment regimens. All 3 dogs had radiographic evidence of megaesophagus and suffered from severe regurgitation. Each dog was initially treated with pyridostigmine and supportive agents. When clinical remission was not achieved, IV MMF was administered to all dogs. Signs of clinical remission were apparent within 48 hours and all dogs were later maintained on oral MMF following resolution of regurgitation.
New or Unique Information Provided – This is the first report of the use of IV MMF as adjunctive treatment in dogs with severe generalized myasthenia gravis. Outcome was favorable in all 3 dogs and no adverse effects were noted from the MMF.     

Detection of specific antibody responses to vaccination in variable flying foxes (Pteropus hypomelanus)

Megachiropteran bats are biologically important both as endangered species and reservoirs for emerging human pathogens. Reliable detection of antibodies to specific pathogens in bats is thus epidemiologically critical. Eight variable flying foxes (Pteropus hypomelanus) were immunized with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA). Each bat received monthly inoculations for 2 months. Affinity-purified IgG was used for production of polyclonal and monoclonal anti-variable flying fox IgG antibodies. ELISA and western blot analysis were used to monitor immune responses and for assessment of polyclonal and monoclonal antibody species cross-reactivity. Protein G, polyclonal antibodies, and monoclonal antibodies detected specific anti-DNP antibody responses in immunized variable flying foxes, with protein G being the most sensitive, followed by monoclonal antibodies and then polyclonal antibodies. While the polyclonal antibody was found to cross-react well against IgG of all bat species tested, some non-specific background was observed. The monoclonal antibody was found to cross-react well against IgG of six other species in the genus Pteropus and to cross-react less strongly against IgG from Eidolon helvum or Phyllostomus hastatus. Protein G distinguished best between vaccinated and unvaccinated bats, and these results validate the use of protein G for detection of bat IgG. Monoclonal antibodies developed in this study recognized immunoglobulins from other members of the genus Pteropus well, and may be useful in applications where specific detection of Pteropus IgG is needed.     

Feline leukaemia. ABCD guidelines on prevention and management

OverviewFeline leukaemia virus (FeLV) is a retrovirus that may induce depression of the immune system, anaemia and/or lymphoma. Over the past 25 years, the prevalence of FeLV infection has decreased considerably, thanks both to reliable tests for the identification of viraemic carriers and to effective vaccines.InfectionTransmission between cats occurs mainly through friendly contacts, but also through biting. In large groups of non-vaccinated cats, around 30–40% will develop persistent viraemia, 30–40% show transient viraemia and 20–30% seroconvert. Young kittens are especially susceptible to FeLV infection.Disease signsThe most common signs of persistent FeLV viraemia are immune suppression, anaemia and lymphoma. Less common signs are immune-mediated disease, chronic enteritis, reproductive disorders and peripheral neuropathies. Most persistently viraemic cats die within 2–3 years.DiagnosisIn low-prevalence areas there may be a risk of false-positive results; a doubtful positive test result in a healthy cat should therefore be confirmed, preferably by PCR for provirus. Asymptomatic FeLV-positive cats should be retested.Disease managementSupportive therapy and good nursing care are required. Secondary infections should be treated promptly. Cats infected with FeLV should remain indoors. Vaccination against common pathogens should be maintained. Inactivated vaccines are recommended. The virus does not survive for long outside the host.Vaccination recommendationsAll cats with an uncertain FeLV status should be tested prior to vaccination. All healthy cats at potential risk of exposure should be vaccinated against FeLV. Kittens should be vaccinated at 8–9 weeks of age, with a second vaccination at 12 weeks, followed by a booster 1 year later. The ABCD suggests that, in cats older than 3–4 years of age, a booster every 2–3 years suffices, in view of the significantly lower susceptibility of older cats.     

Feline rabies. ABCD guidelines on prevention and management

OverviewRabies virus belongs to the genus Lyssavirus, together with European bat lyssaviruses 1 and 2. In clinical practice, rabies virus is easily inactivated by detergent-based disinfectants.InfectionRabid animals are the only source of infection. Virus is shed in the saliva some days before the onset of clinical signs and transmitted through a bite or a scratch to the skin or mucous membranes. The average incubation period in cats is 2 months, but may vary from 2 weeks to several months, or even years.Disease signsAny unexplained aggressive behaviour or sudden behavioural change in cats must be considered suspicious. Two disease manifestations have been identified in cats: the furious and the dumb form. Death occurs after a clinical course of 1–10 days.DiagnosisA definitive rabies diagnosis is obtained by post-mortem laboratory investigation. However, serological tests are used for post-vaccinal control, especially in the context of international movements.Disease managementPost-exposure vaccination of cats depends on the national public health regulations, and is forbidden in many countries.Vaccination recommendationsA single rabies vaccination induces a long-lasting immunity. Kittens should be vaccinated at 12–16 weeks of age to avoid interference from maternally derived antibodies and revaccinated 1 year later. Although some vaccines protect against virulent rabies virus challenge for 3 years or more, national or local legislation may call for annual boosters.     

Development of the polysaccharidic matrix in biocrusts induced by a cyanobacterium inoculated in sand microcosms

Soil inoculation with cyanobacteria (cyanobacterization) is a biotechnological method widely studied to improve soil quality and productivity. During their growth on soil, cyanobacteria excrete exopolysaccharides (EPSs) which glue trichomes to soil particles, in a three-dimensional extracellular polymeric matrix. EPS productivity is an important screening parameter to select proficient inoculants and is affected by growth conditions and abiotic stresses. In this study, we evaluated the capability of the cyanobacterium Schizothrix cf. delicatissima AMPL0116 to form biocrusts when inoculated in sand microcosms under stressing conditions, and the characteristics of the synthesized polymeric matrix. In parallel, we evaluated the characteristics of exopolysaccharidic exudates of the strain when grown in liquid culture, under optimal growth setting. Our results pointed out at significant differences of the exopolymers produced in the two conditions in terms of monosaccharidic composition and molecular weight distribution, and proved the capability of S. cf. delicatissima AMPL0116 to form stable bioaggregates on sandy soils.