Horses with intracranial lesions and severe ataxia are not good anesthesia candidates; however, only one method to obtain cerebrospinal fluid (CSF) from the cervical region in a standing horse has been reported. This method is not performed routinely due to the difficulty for sample acquisition. Our hypothesis is that standing cervical centesis can be performed in horses without complication. Ultrasound-guided centesis of the CSF between C1 and C2 in 11 clinically normal horses and two horses with neurologic signs were performed. Horses were sedated and ultrasound was used to identify the subarachnoid space and spinal cord between C1 and C2. With ultrasound guidance, a needle was introduced into the dorsal aspect of the subarachnoid space using a lateral approach. Ten milliliters of CSF was obtained and analyzed. Two normal horses in this study had moderate red blood cell contamination in the CSF (940 and 612 RBC/microl). One horse had 11 RBC/microl and the remaining horses had < 4 RBC/microl. The total procedure time was approximately 2 min. No reaction was observed and no complications were detected up to 48 h after the procedure. Ultrasound-guided centesis between C1 and C2 is a rapid procedure that causes minimal to no reaction in standing, sedated horses used in this study. The use of ultrasound to guide a standing C1-2 centesis of the subarachnoid space provides an additional route to obtain CSF for analysis in the equine patient.

Gammaherpesviruses (γHV) are implicated in the pathogenesis of pulmonary fibrosis in humans and murine models of lung fibrosis, however there is little direct experimental evidence that such viruses induce lung fibrosis in the natural host. The equine γHV EHV 5 is associated with equine multinodular pulmonary fibrosis (EMPF), a progressive fibrosing lung disease in its natural host, the horse. Experimental reproduction of EMPF has not been attempted to date. We hypothesized that inoculation of EHV 5 isolated from cases of EMPF into the lungs of clinically normal horses would induce lung fibrosis similar to EMPF. Neutralizing antibody titers were measured in the horses before and after inoculation with EHV 5. PCR and virus isolation was used to detect EHV 5 in antemortem blood and BAL samples, and in tissues collected postmortem. Nodular pulmonary fibrosis and induction of myofibroblasts occurred in EHV 5 inoculated horses. Mean lung collagen in EHV 5 inoculated horses (80 µg/mg) was significantly increased compared to control horses (26 µg/mg) (p < 0.5), as was interstitial collagen (32.6% ± 1.2% vs 23% ± 1.4%) (mean ± SEM; p < 0.001). Virus was difficult to detect in infected horses throughout the experiment, although EHV 5 antigen was detected in the lung by immunohistochemistry. We conclude that the γHV EHV 5 can induce lung fibrosis in the horse, and hypothesize that induction of fibrosis occurs while the virus is latent within the lung. This is the first example of a γHV inducing lung fibrosis in the natural host.

FP (6 mg q12h) is as effective as DEX for prevention of acute exacerbations of RAO and lower doses should be evaluated. High-dose FP is not as effective as DEX for treatment of RAO exacerbations.

The decrease in the SDs of RIP measurements indicated a lower degree of variability in breathing patterns of RAO-affected horses. This loss of variability may provide an early indicator of airway inflammation.

Background: Lidocaine decreases neutrophilic inflammation in models of acute lung injury and decreases inflammation in asthmatic patients. Neutrophilic bronchiolitis develops in recurrent airway obstruction (RAO), but it remains unknown if lidocaine infusion decreases neutrophil migration into the airways.Hypothesis: Lidocaine decreases neutrophilic inflammation as measured in BALF in RAO-affected horses. Animals: Six RAO-susceptible horses in remission. Methods: In a randomized cross-over design, horses received lactated Ringer's solution (LRS) IV or lidocaine hydrochloride IV with a minimum of 4 weeks at pasture between treatments. Treatments were delivered as continuous infusions beginning 4 hours before and for 68 hours during exposure to hay and straw challenge. Clinical score (CS, grade 0-8), maximal change in pleural pressure (ΔPpl max ), and bronchoalveolar lavage fluid (BALF) cytology were measured at baseline and the end of challenge (day 4). Plasma lidocaine concentrations were monitored daily.Results: At baseline, there were no significant differences in variables between treatments. Plasma lidocaine concentration was consistently > 1100 ng/mL. After challenge, CS increased significantly [baseline: 2/8 (2-3), [median (interquartile range)]; day 4: 4/8 (4-5) P = .0006] as did ΔPpl max [baseline: 3.6 (2.63-4.95) cmH 2 0; day 4: 9.62 (6.5-16) P = .0036], but there was no difference between treatments. Percentage of neutrophils was not different between treatments, but lidocaine infusion significantly increased BALF total cells [baseline: LRS 2.18 ± 0.82 9 10 5 cells/mL (mean ± SD), lidocaine 1.6 ± 0.3 9 10

Heaves, an asthma-like chronic inflammatory airway disease, becomes clinically evident in susceptible middle-aged horses (Robinson et al. 2001). Acute inflammation and airway obstruction are caused by inhalation of dust in stables. Lung function tests [pulmonary resistance (RL), dynamic compliance (Cdyn) and change in pleural pressure (Ppl)] are difficult to perform in untrained animals and a simpler quantitative measure is needed. Respiratory inductance plethysmography (RIP) measures changes in thoracic and abdominal cross sectional area, the sum of which indicates the total respiratory displacement (RIPtd) during each breath. The hypothesis tested was "RIP identifies changes in pattern of breathing prior to changes in conventional pulmonary function tests". Two groups, control and RAO-affected (8 pairs), were brought from pasture and stabled for 7 days. RIP bands (eMKA Technologies) recorded respiratory rate (RIPf) and RIPtd for 24 h/day in 4h segments. RL, Cdyn and Ppl were measured once daily. RL, Cdyn and Ppl did not differ between groups when horses came from pasture but differed significantly after several days of stabling (Repeated measures ANOVA). Although means of RIPf and RIPtd did not differ between groups or change significantly during stabling, examination of real-time data suggested differences in variability of breathing pattern between horse groups. We tested this statistically by calculating the standard deviation (SD) of RIPtd and RIPf in each of the 4-h segments. SD of RIPtd and RIPf significantly decreased in RAO-affected horses by eight hours after stabling and remained significantly decreased during stabling. This decrease in RIPf SD in RAO-affected horses was due to decreases in SD of both inspiratory and expiratory duration. Furthermore, SD decreased during the night in RAO-affected horses but not controls. Because SDs differed between groups when lung function did not, these may be a sensitive indicator of airway obstruction in heaves. However, the decreased RIPtd and RIPf SD in RAO-affected horses within eight hours of stabling coincides with neutrophil influx into the lung after 6 hours of stabling (Fairbairn et al. 1993). Therefore this RIP method may be unveiling inflammatory mechanisms that are affecting control of respiratory frequency and tidal volume during the development of clinical exacerbations of RAO.

Traditional classification of breast cancer subtype is determined based on protein expression and genetic profile. Determining the molecular subtype of breast cancer can make prognosis more accurate and help to personalize treatment. More aggressive subtypes of breast cancer, such as basal-like and Her2 + , have mutations that alter the protein regulation of the cell cytoskeleton. These cytoskeleton modulations can enable the cell to become more mobile and metastasize to other parts of the body. High-frequency ultrasound (10–100 MHz) has previously been studied for the real-time diagnosis of malignant tissue in breast conservation surgery. High-frequency ultrasound also has the potential of determining the molecular subtype of breast cancer. The objective of this work was to determine if chemically induced changes in the cytoskeleton of cancer cell lines are able to be detected using high-frequency ultrasound. Cell cultures of a human pancreatic carcinoma cell line (panc-1) were grown in monolayers and then treated with sphingosylphosphorylcholine (SPC), a bioactive lipid that rearranges the keratin components of the cytoskeleton. Pulse-echo measurements of the cultures were taken over a period of one hour. The results of this work demonstrate that high-frequency ultrasonic spectra are sensitive to the cytoskeleton changes induced by SPC.

High-frequency ultrasound (10–100 MHz) has been demonstrated to be sensitive to cell cytoskeletal changes. Cytoskeletal properties determine the biomechanical characteristics of cells and their role in many biomolecular processes. Examples include the aggressiveness and metastatic potential of breast cancer subtypes, T-cell activation during immune responses, and microtubule disintegration in Alzheimer’s disease. The objectives of this work were to optimize the use of high-frequency ultrasound to subtype breast cancer cells and to acoustically measure cytoskeletal modifications. Pulse-echo measurements of 7 breast cancer cell lines of different molecular subtypes were acquired over a 2.5-year period using a 50-MHz transducer immersed in the growth media of monolayer cell cultures. Cell reflections were isolated from the interfering cell-culture plate reflections, spectrally analyzed using Gaussian curve fits, and spectrally classified using a heat map. The heat map displayed distinct patterns that differentiated the cell lines by molecular subtype. Cell cultures were also treated with colchicine and sphingosylphosphorylcholine to observe modulation of the microtubule and actin components. Cell waveforms and spectra displayed time-dependent changes due to chemical modification of the cytoskeleton. These results further verify and improve the noninvasive use of high-frequency ultrasound to differentiate breast cancer subtypes and to monitor cytoskeletal alterations in real time.