Quantitative assessment of nociception in horses by use of the nociceptive withdrawal reflex evoked by transcutaneous electrical stimulation

OBJECTIVES: To evoke and measure the nociceptive withdrawal reflex (NWR) by use of electromyographic recordings and to score the behavioral nociceptive responses to electrical pulses in standing nonsedated horses. ANIMALS: 10 adult horses. PROCEDURE: The lateral palmar digital nerve of the forelimb was transcutaneously stimulated, and surface electromyographic responses were recorded from the ulnaris lateralis, extensor carpi radialis, and common digital extensor muscles. Stimuli consisted of a 25-millisecond train of 5 constant-current pulses delivered by a computer-controlled stimulator. The 80- to 250-milliseconds poststimulation interval was analyzed to detect the NWR. The current intensity was increased in steps of 0.5 mA until the NWR threshold intensity (lt) was reached. The stimulus at It was repeated twice. Latency and amplitude of the NWR, together with the behavioral reaction of horses, were analyzed. The latter was scored according to a scale from 0 (no reaction) to 5 (vigorous reaction). Finally, 3 suprathreshold stimuli at 1.2 X It were analyzed. RESULTS: The median It to elicit NWR was 2.5 mA. Median onset latency of the NWR was 96.0 milliseconds at It and 89.6 milliseconds for suprathreshold stimuli. The amplitude of the reflexes was higher for suprathreshold stimulations, and behavioral reactions were slightly stronger when stimulus intensity increased. CONCLUSIONS AND CLINICAL RELEVANCE: Results of our study indicate that it is possible to record NWR in conscious standing horses, to define a reflex threshold, and to measure reflexes in response to increasing stimulus intensity.     

Air-coupled ultrasound as an accurate and reproducible method for bonding assessment of glued timber

Glued timber products are widely used in construction; therefore, it is necessary to develop non-destructive bonding quality assessment methods for long-term structural health monitoring. Air-coupled ultrasound (ACU) inspection is a novel technique, with phenomenal improvements in reproducibility compared to traditional contact ultrasonics, unlimited scanning possibilities, and a high potential for delamination detection in wood products. As part of an ongoing project, glued timber samples of 10 mm thickness with artificial glue line defects were inspected. A normal through-transmission set-up with 120 kHz transducers allowed for successful and accurate imaging of the geometry of glued and non-glued areas in all inspected objects. The influence of wood heterogeneity and the reproducibility of ACU amplitude measurements were analysed in detail, identifying the main sources of variation. Future work is planned for the inspection of more complex glued timber objects.     

Cyclophosphamide exerts no beneficial effect over prednisone alone in the initial treatment of acute immune-mediated hemolytic anemia in dogs: a randomized controlled clinical trial

Cyclophosphamide is commonly used with prednisone in the initial treatment of severe idiopathic immune-mediated hemolytic anemia (IMHA) in dogs because retrospective reports suggest its benefit. This randomized controlled prospective clinicaltrial evaluated whether combined cyclophosphamide and prednisone therapy is more efficacious than prednisone therapy alone in the initial treatment of IMHA. Eighteen dogs with acute, severe idiopathic IMHA were randomly assigned to 1 of 2 treatment groups. The P group received prednisone therapy alone (1-2 mg/kg PO q12h), and the PC group received prednisone (1-2 mg/kg PO q12h) and cyclophosphamide (50 mg/m2 PO q24h for 4 consecutive days a week) for 4 weeks. The mortality rate in the P group was 20% (2 of 10), and in the PC group, the mortality rate was 38% (3 of 8). There was no difference in sequential CBC evaluations between the 2 groups. However, whereas dogs in the P group showed increases in reticulocyte count, reticulocytosis was suppressed in dogs in the PC group during the 1st week of therapy. Spherocytosis resolved more quickly in the P group (day 21) than in the PC group (day 28), but the time taken to achieve a negative Coombs' test result was comparable between groups. No difference was observed in the volume of packed red blood cells (pRBCs) given per transfusion between treatment groups, but more dogs in the PC group required a 2nd transfusion. The results of this limited study suggest that cyclophosphamide plus prednisone has no benefit over prednisone alone in the initial treatment of acute, severe idiopathic IMHA indogs.     

Comparative clinical study of canine and feline total blood cell count results with seven in‐clinic and two commercial laboratory hematology analyzers

Background: A CBC is an integral part of the assessment of health and disease in companion animals. While in the past newer technologies for CBC analysis were limited to large clinical pathology laboratories, several smaller and affordable automated hematology analyzers have been developed for in‐clinic use. Objectives: The purpose of this study was to compare CBC results generated by 7 in‐clinic laser‐ and impedance‐based hematology instruments and 2 commercial laboratory analyzers. Methods: Over a 3‐month period, fresh EDTA‐anticoagulated blood samples from healthy and diseased dogs (n=260) and cats (n=110) were analyzed on the LaserCyte, ForCyte, MS45, Heska CBC, Scil Vet ABC, VetScan HMT, QBC Vet Autoread, CELL‐DYN 3500, and ADVIA 120 analyzers. Results were compared by regression correlation (linear, Deming, Passing‐Bablok) and Bland–Altman bias plots using the ADVIA as the criterion standard for all analytes except HCT, which was compared with manual PCV. Precision, linearity, and carryover also were evaluated. Results: For most analytes, the in‐clinic analyzers and the CELL‐DYN performed similarly and correlated well with the ADVIA. The biases ranged from ?0.6 to 2.4 × 10⁹/L for WBC count, 0 to 0.9 × 10¹²/L for RBC count, ?1.5 to 0.7 g/dL for hemoglobin concentration, ?4.3 to 8.3 fL for MCV, and ?69.3 to 77.2 × 10⁹/L for platelet count. Compared with PCV, the HCT on most analyzers had a bias from 0.1% to 7.2%. Canine reticulocyte counts on the LaserCyte and ForCyte correlated but had a negative bias compared with those on the ADVIA. Precision, linearity, and carryover results were excellent for most analyzers. Conclusions: Total WBC and RBC counts were acceptable on all in‐clinic hematology instruments studied, with limitations for some RBC parameters and platelet counts. Together with evaluation of a blood film, these in‐clinic instruments can provide useful information on canine and feline patients in veterinary practices.     

A kinetic framework for a mammalian RNA polymerase in vivo

We have analyzed the kinetics of assembly and elongation of the mammalian RNA polymerase I complex on endogenous ribosomal genes in the nuclei of living cells with the use of in vivo microscopy. We show that components of the RNA polymerase I machinery are brought to ribosomal genes as distinct subunits and that assembly occurs via metastable intermediates. With the use of computational modeling of imaging data, we have determined the in vivo elongation time of the polymerase, and measurements of recruitment and incorporation frequencies show that incorporation of components into the assembling polymerase is inefficient. Our data provide a kinetic and mechanistic framework for the function of a mammalian RNA polymerase in living cells.     

The neural basis of altruistic punishment

Many people voluntarily incur costs to punish violations of social norms. Evolutionary models and empirical evidence indicate that such altruistic punishment has been a decisive force in the evolution of human cooperation. We used H2 15O positron emission tomography to examine the neural basis for altruistic punishment of defectors in an economic exchange. Subjects could punish defection either symbolically or effectively. Symbolic punishment did not reduce the defector's economic payoff, whereas effective punishment did reduce the payoff. We scanned the subjects' brains while they learned about the defector's abuse of trust and determined the punishment. Effective punishment, as compared with symbolic punishment, activated the dorsal striatum, which has been implicated in the processing of rewards that accrue as a result of goal-directed actions. Moreover, subjects with stronger activations in the dorsal striatum were willing to incur greater costs in order to punish. Our findings support the hypothesis that people derive satisfaction from punishing norm violations and that the activation in the dorsal striatum reflects the anticipated satisfaction from punishing defectors.     

Requirement of JNK2 for scavenger receptor A-mediated foam cell formation in atherogenesis

In vitro studies suggest a role for c-Jun N-terminal kinases (JNKs) in proatherogenic cellular processes. We show that atherosclerosis-prone ApoE-/- mice simultaneously lacking JNK2 (ApoE-/- JNK2-/- mice), but not ApoE-/- JNK1-/- mice, developed less atherosclerosis than do ApoE-/- mice. Pharmacological inhibition of JNK activity efficiently reduced plaque formation. Macrophages lacking JNK2 displayed suppressed foam cell formation caused by defective uptake and degradation of modified lipoproteins and showed increased amounts of the modified lipoprotein-binding and -internalizing scavenger receptor A (SR-A), whose phosphorylation was markedly decreased. Macrophage-restricted deletion of JNK2 was sufficient to decrease atherogenesis. Thus, JNK2-dependent phosphorylation of SR-A promotes uptake of lipids in macrophages, thereby regulating foam cell formation, a critical step in atherogenesis.     

Serodiagnosis and monitoring of contagious bovine pleuropneumonia (CBPP) with an indirect ELISA based on the specific lipoprotein LppQ of Mycoplasma mycoides subsp. mycoides SC.

An indirect ELISA, based on the specific and strongly antigenic recombinant peptide of the N'-terminal half of the lipoprotein LppQ from Mycoplasma mycoides subsp. mycoides small colony type (SC) was developed for the detection of antibodies to M. mycoides subsp. mycoides SC. It was evaluated for its suitability for serodiagnosis and monitoring of contagious bovine pleuropneumonia (CBPP). The recombinant peptide containing poly-histidine residue tails was expressed in Escherichia coli and subsequently purified by Ni(2+) chelate affinity chromatography to be used as antigen to coat microtiter ELISA plates. The specificity of the antigen was tested against rabbit hyperimmune sera directed against related Mycoplasmas of the M. mycoides cluster and with sera from cattle that were either free of CBPP, but suffered from other mycoplasmal infections such as M. bovis, or showed cross-reactions in the complement fixation test. The sensitivity of the ELISA was assessed with sera from artificially infected animals and with sera from cattle originating from areas where CBPP was endemic at the time of blood sampling. The study revealed that the ELISA was both specific and sensitive for CBPP positive bovine sera and was shown also to be robust to harsh climatic conditions.     

Spectral assessments of phenotypic differences in spike development during grain filling affected by varying N supply in wheat

Single plant traits such as green biomass, spike dry weight, biomass, and nitrogen (N) transfer to grains are important traits for final grain yield. However, methods to assess these traits are laborious and expensive. Spectral reflectance measurements allow researchers to assess cultivar differences of yield‐related plant traits and translocation parameters that are affected by varying amounts of available N. In a field experiment, six high‐yielding wheat cultivars were grown with N supplies of 0, 100, 160, and 220 kg N ha^–1. Wheat canopies were observed spectrally throughout the grain‐filling period, and three spectral parameters were calculated. To describe the development of the vegetative plant parts (leaves + culms) and the spikes, plants were sampled four times during grain filling. Dry weights and the relative dry‐matter content were recorded for leaves + culms and spikes. The N status of the plants was assessed by measuring the total N concentration and by calculating the aboveground N uptake. Good correlations were found between spectral indices and single plant traits throughout grain filling but varied with N supply and development stage. The normalized difference vegetation index, NDVI, was strongly affected by the saturation effects of increased N concentration. The red‐edge inflection point, REIP, predicted plant traits with r² values up to 0.98. However, in plants with advanced senescence, the REIP was less efficient in describing plant traits. The NIR‐based index R₇₆₀/R₇₃₀ was closely related to yield‐related plant traits at early grain filling. Compared to the REIP, the R₇₆₀/R₇₃₀ index was resistant to strong chlorophyll decays being able to predict plant traits at late grain filling, with r² values of up to 0.92. Spectral reflectance measurements may represent a promising tool to assess phenotypic differences in yield‐related plant traits during grain filling.