Recovery of brodifacoum in vomitus following induction of emesis in dogs that had ingested rodenticide bait

AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.     

Localization of metastable atom beams with optical standing waves: nanolithography at the heisenberg limit

The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography.     

Pharmacokinetics of oral terbinafine in adult horses

The primary study objective was to compare the pharmacokinetics of p.o. terbinafine alone to p.o. terbinafine administered with p.o. cimetidine in healthy adult horses. The second objective was to assess the pharmacokinetics of terbinafine when administered per rectum in two different suspensions at 30 mg/kg to adult horses. Six healthy adult horses were included in this crossover study. Plasma terbinafine concentrations were quantified with liquid chromatography and mass spectrometry. The half‐life (geometric mean) was 8.38 and 10.76 h, for p.o. alone and p.o. with cimetidine, respectively. The mean maximum plasma concentrations were 0.291 μg/mL at 1.54 h and 0.418 μg/mL at 1.28 h for p.o. alone and p.o. with cimetidine, respectively. Terbinafine with cimetidine had an average C_MAX 44% higher and the relative F was 153% compared p.o. terbinafine alone, but was not statistically different (P > 0.05). Terbinafine was infrequently detected when administered per rectum in two different suspensions (water or olive oil). Minor adverse effects included oral irritation, fever, and colic. All resolved spontaneously. More pharmacokinetic studies are indicated assessing drug–drug interactions and using multiple dosing intervals to improve our knowledge of effective oral dosing, the potential for drug accumulation, and systemic adverse effect of terbinafine in horses.     

Systemic Immunosuppression by Methylprednisolone and Pregnancy Rates in Goats Undergoing the Transfer of Cloned Embryos

The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos.     

Amyloid protein precursor messenger RNAs: differential expression in Alzheimer's disease

In situ hybridization was used to assess total amyloid protein precursor (APP) messenger RNA and the subset of APP mRNA containing the Kunitz protease inhibitor (KPI) insert in 11 Alzheimer's disease (AD) and 7 control brains. In AD, a significant twofold increase was observed in total APP mRNA in nucleus basalis and locus ceruleus neurons but not in hippocampal subicular neurons, neurons of the basis pontis, or occipital cortical neurons. The increase in total APP mRNA in locus ceruleus and nucleus basalis neurons was due exclusively to an increase in APP mRNA lacking the KPI domain. These findings suggest that increased production of APP lacking the KPI domain in nucleus basalis and locus ceruleus neurons may play an important role in the deposition of cerebral amyloid that occurs in AD.     

Complex stifle injury in a foal

A 130 kg, 60-day-old Quarter Horse male foal presented with bilateral stifle effusion and severe left hindlimb lameness. Clinical examination and imaging including radiography, ultrasound and computed tomography revealed bilateral stifle trauma. Specifically, disruption of the left medial meniscus and deep bone injury to the left medial femoral condyle (MFC) were detected, and bilateral injury to the origin of the cranial cruciate ligaments was suspected. Treatment consisted of stall rest and joint injection with corticosteroids, however there was little improvement in lameness. Due to the poor prognosis for soundness, the foal was subject to euthanasia 10 weeks after initial presentation. Post-mortem examination supported the left medial meniscus and MFC injuries and revealed avulsions of the origin of the cranial cruciate ligaments (complete on the left and partial on the right) from the lateral femoral condyle. Histopathology of the left stifle joint revealed varying depths of MFC osteochondral injury and severe left medial meniscus damage.     

Surface Deformation and Lower Crustal Flow in Eastern Tibet

Field observations and satellite geodesy indicate that little crustal shortening has occurred along the central to southern margin of the eastern Tibetan plateau since about 4 million years ago. Instead, central eastern Tibet has been nearly stationary relative to southeastern China, southeastern Tibet has rotated clockwise without major crustal shortening, and the crust along portions of the eastern plateau margin has been extended. Modeling suggests that these phenomena are the result of continental convergence where the lower crust is so weak that upper crustal deformation is decoupled from the motion of the underlying mantle. This model also predicts east-west extension on the high plateau without convective removal of Tibetan lithosphere and without eastward movement of the crust east of the plateau.     

Evaluation of plasma concentration after intravenous and intramuscular penicillin administration over 24 hr in healthy adult horses

Penicillin is administered intravenously (IV) or intramuscularly (IM) to horses for the prevention and treatment of infections, and both routes have disadvantages. To minimize these shortcomings, a 24‐hr hybrid administration protocol (HPP) was developed. Our objective was to determine penicillin plasma concentrations in horses administered via HPP. Venous blood was collected from seven healthy horses administered IV potassium penicillin G at 0 and 6 hr and IM procaine penicillin G at 12 hr. Blood was collected at 2‐hr intervals from 0 to 20 hr and at 24 hr. Plasma penicillin concentrations were measured using liquid chromatography and mass spectrometry. Penicillin susceptibility from equine isolates was examined to determine pharmacodynamic targets. The MIC₉₀ of penicillin for 264 isolates of Streptococcus sp. was ≤0.06 μg/ml. For the 24‐hr dosing interval, the mean plasma penicillin concentration was >0.07 μg/ml. Five horses (72%) exceeded 0.06 μg/ml for 98% of the dosing interval, and two horses exceeded this value for 52%–65% of the dosing interval. The HPP achieved mean plasma penicillin concentrations in healthy adult horses above 0.07 μg/ml for a 24‐hr dosing interval. However, individual variations in plasma concentrations were apparent and deserve future clinical study.