OBJECTIVE To evaluate the lipidomic profile of surfactant obtained from horses with asthma at various clinical stages and to compare results with findings for healthy horses exposed to the same conditions.
SAMPLE Surfactant samples obtained from 6 horses with severe asthma and 7 healthy horses.
PROCEDURES Clinical evaluation of horses and surfactant analysis were performed. Samples obtained from horses with severe asthma and healthy horses before (baseline), during, and after exposure to hay were analyzed. Crude surfactant pellets were dried prior to dissolution in a solution of isopropanol:methanol:chloroform (4:2:1) containing 7.5mM ammonium acetate. Shotgun lipidomics were performed by use of high-resolution data acquisition on an ion-trap mass spectrometer. Findings were analyzed by use of an ANOVA with a Tukey-Kramer post hoc test.
RESULTS Results of lipidomic analysis were evaluated to detect significant differences between groups of horses and among exposure statuses within groups of horses. Significantly increased amounts of cyclic phosphatidic acid (cPA) and diacylglycerol (DAG) were detected in surfactant from severely asthmatic horses during exposure to hay, compared with baseline and postexposure concentrations. Concentrations of cPA and DAG did not change significantly in healthy horses regardless of exposure status.
CONCLUSIONS AND CLINICAL RELEVANCE cPA 16:0 and DAG 36:2 were 2 novel lipid mediators identified in surfactant obtained from asthmatic horses with clinical disease. These molecules were likely biomarkers of sustained inflammation. Further studies are needed to evaluate a possible correlation with disease severity and potential alterations in the plasma lipidomic profile of horses with asthma.
Case Description—A 1.5-year-old spayed female domestic shorthair cat was admitted for hind limb locomotor difficulties and signs of pain along the lumbar portion of the vertebral column. At the time of referral, the cat was paraparetic with deficits in the spinal reflexes of the hind limbs. Neuroanatomic localization was at the L6-S2 spinal cord segments, corresponding approximately to the region of the L4-L6 vertebral bodies.
Clinical Findings—Radiography revealed a mixed osteolytic-proliferative lesion within the body of L5 involving the cranial end plate, as well as punctate radiolucencies in the distal portion of the femur. Magnetic resonance imaging revealed an intramedullary spinal cord lesion along with extensive meningeal and nerve root lesions in the area of the L4-L6 vertebral bodies. Cytologic analysis of a bone marrow aspirate from the right trochanteric fossa revealed a substantial plasma cell infiltrate. Analysis of CSF revealed a high protein concentration and morphologically abnormal plasma cells. Urine, but not serum, protein electrophoresis revealed a sharp γ-globulin peak consistent with a monoclonal band of Bence-Jones proteins. The diagnosis was multiple myeloma.
Treatment and Outcome—The cat was treated with melphalan and prednisolone. A rapid clinical response was reported, and by week 3 after diagnosis, the cat's locomotion and behavior had normalized. However, by month 4, multifocal neurologic deficits were evident. The cat was euthanized at 9 months because of tetraparesis and substantial weight loss.
Clinical Relevance—To our knowledge, this is the first report of myeloma in a cat that had electrophoretically detectable light chain proteinuria but lacked a detectable serum monoclonal gammopathy.
To evaluate surfactant protein D (SP-D) concentrations in serum and bronchoalveolar lavage fluid (BALF) from young healthy horses on pasture or housed in a typical barn.
20 young healthy horses.
Horses were randomly assigned to 1 of 2 groups (pasture, n = 10; barn, 10), and serum and BALF samples were collected for SP-D determination at baseline (all horses on pasture) and 2 weeks and 4 weeks after the barn group of horses was relocated from the pasture to the barn. Other evaluations included physical and tracheoscopic examinations. Findings were compared within and between groups.
Physical and tracheoscopic examinations, CBC, and serum biochemical analysis did not reveal evidence of respiratory disease, and no significant differences were present within and between groups. Serum SP-D concentrations did not significantly differ within and between groups, but BALF SP-D concentrations were significantly lower for the barn group at 2 weeks but not at 4 weeks, compared with baseline. The BALF SP-D concentration-to-BALF total protein concentration ratio was < 1.5 and did not significantly differ within and between groups.
CONCLUSIONS AND CLINICAL RELEVANCE
A mild decrease was evident in the concentration of SP-D in the BALF collected from young healthy horses after 2 weeks of exposure to a barn environment. The clinical importance of this finding remains to be determined.
Objective—To determine percentages of domestic cats and dogs vaccinated against rabies, identify barriers to vaccination, and assess knowledge about rabies in a semirural New Mexico community after a skunk rabies outbreak.
Sample—366 residential properties in Eddy County, NM.
Procedures—The New Mexico Department of Health and CDC administered surveys and analyzed data.
Results—Individuals at 247 of the 366 residential properties participated in the survey. One hundred eighty of the 247 (73%) households owned a dog (n = 292) or cat (163). Cats were more likely than dogs to not have an up-to-date rabies vaccination status (prevalence ratio, 3.2; 95% confidence interval, 2.3 to 4.4). Cost and time or scheduling were the most frequently identified barriers to vaccination. One hundred sixty (65%) respondents did not know livestock can transmit rabies, 78 (32%) did not know rabies is fatal, and 89 (36%) did not know a bat scratching a person can be an exposure. Only 187 (76%) respondents indicated they would contact animal control if they saw a sick skunk, and only 166 (67%) indicated they would contact animal control if bitten by a dog they did not own.
Conclusions and Clinical Relevance—Findings indicated that rabies vaccination prevalence among pet dogs and cats was low, despite the fact that the region had experienced a skunk rabies outbreak during the previous 2 years. In addition, substantial percentages of respondents did not have correct knowledge of rabies or rabies exposure.
To perform lipidomic analysis of surfactant and plasma from asthmatic and healthy horses.
30 horses with clinical signs of asthma and 30 age-matched control horses.
Detailed history, physical examination, CBC, and bronchoalveolar lavage fluid (BALF) cytologies were obtained. Asthmatic horses were grouped based on their BALF inflammatory profile: severe equine asthma (SEA), mild equine asthma with neutrophilic airway inflammation (MEA-N), or mild equine asthma with eosinophilic airway inflammation (MEA-E). Each asthma group was assigned its own age-matched control group. Lipidomic analysis was completed on surfactant and plasma. Surfactant protein D (SP-D) concentrations were measured in serum and BALF.
SEA surfactant was characterized by a phospholipid deficit and altered composition (increased ceramides, decreased phosphatidylglycerol, and increased cyclic phosphatidic acid [cPA]). In comparison, MEA-N surfactant only had a decrease in select phosphatidylglycerol species and increased cPA levels. The plasma lipidomic profile was significantly different in all asthma groups compared to controls. Specifically, all groups had increased plasma phytoceramide. SEA horses had increased plasma cPA and diacylglycerol whereas MEA-N horses only had increased cPA. MEA-E horses had increases in select ceramides and dihydrocermides. Only SEA horses had significantly increased serum SP-D concentrations.
The most significant surfactant alterations were present in SEA (altered phospholipid content and composition); only mild changes were observed in MEA-N horses. The plasma lipidomic profile was significantly altered in all groups of asthmatic horses and differed among groups. Data from a larger population of asthmatic horses are needed to assess implications for diagnosis, prognosis, and treatment.