Purification and further characterization of phenol extract from Listeria monocytogenes

A phenol-water extract of Listeria monocytogenes virulent strains 9-125 (serotype 4b) was purified by 3 cycles of ultracentrifugation. The purified extract reacted positively in Limulus amoebocyte lysate assay at a concentration of 1 microgram/ml. This value was 1,000 times higher than that for Salmonella abortus equi lipopolysaccharide. The phenol extract was toxic to chicken embryos (median lethal dose was 40.5 micrograms) and contained carbohydrates (heptose, hexose, hexosamine, methylpentose, 2-keto-3-deoxyoctanate, dideoxyhexose), lipid, 16 amino acids in the protein moiety, glucosamine, galactosamine, phosphorus, and ribonucleic acid.     

Incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets

OBJECTIVE: To determine incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets. DESIGN: Retrospective cohort study. ANIMALS: 3,587 ferrets that received a rabies or distemper vaccine between January 1, 2002, and December 31, 2003. PROCEDURES: Electronic medical records were searched for possible vaccine-associated adverse events. Adverse events were classified by attending veterinarians as nonspecific vaccine reactions, allergic reactions, or anaphylaxis. Patient information that was collected included age, weight, sex, cumulative number of distemper and rabies vaccinations received, clinical signs, and treatment. The association between potential risk factors and occurrence of an adverse event was estimated with logistic regression. RESULTS: 30 adverse events were recorded. The adverse event incidence rates for administration of rabies vaccine alone, distemper vaccine alone, and rabies and distemper vaccines together were 0.51%, 1.00%, and 0.85%, respectively. These rates were not significantly different. All adverse events occurred immediately following vaccine administration and most commonly consisted of vomiting and diarrhea (52%) or vomiting alone (31%). Age, sex, and body weight were not significantly associated with occurrence of adverse events, but adverse event incidence rate increased as the cumulative number of distemper or rabies vaccinations received increased. In multivariate logistic regression analysis, only the cumulative number of distemper vaccinations received was significantly associated with the occurrence of an adverse event. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in ferrets, the risk of vaccine-associated adverse events was primarily associated with an increase in the number of distemper vaccinations.     

In vitro evaluation of the contractile response to endothelin-1 of the circular and longitudinal myometrial layers of the uterine horn of nongravid mares

OBJECTIVE: To characterize the in vitro response of circular and longitudinal myometrial layers of the uterine horn (CMLH and LMLH, respectively) of horses to endothelin (ET)-1 by use of specific ETA (BQ-123) and ETB (IRL-1038) receptor antagonists. SAMPLE POPULATION: Uteruses from 10 nongravid mares in anestrus. PROCEDURE: Muscle strips from the CMLH and LMLH were suspended in tissue baths and connected to force-displacement transducers interfaced with a polygraph. Strips were incubated for 45-minute intervals with no antagonist (control specimens), and 3 concentrations (10(-9), 10(-7), and 10(-5)M) of BQ-123, IRL-1038, or BQ-123 and IRL-1038 before concentration-response curves to ET-1 were generated. Contractile response to cumulative concentrations of ET-1 (10(-9) to 10(-6)M) was quantified by measuring change in the area under the curve (AUC) for the 3-minute period after each ET-1 dose. RESULTS: ET-1 caused concentration-dependent contraction of the CMLH and LMLH specimens. Application of BQ-123 decreased AUC values for both layers. Application of IRL-1038 increased the AUC value for LMLH specimens but did not affect the CMLH value. The combination of BQ-123 and IRL-1038 decreased the AUC value for LMLH tissue and increased that for CMLH tissue. CONCLUSIONS AND CLINICAL RELEVANCE: ET-1 causes contraction of the CMLH and LMLH in nongravid horses. In both layers, ETA receptors mediate contraction but the role of ETB receptors remains unclear. In the LMLH, ETA receptors have a dominant role; the presence of another receptor or receptor subtype within this layer is suggested. These findings support a physiologic role for ET-1 in uterine contractility.     

Concentrations of serum amyloid A and lipopolysaccharide-binding protein in horses with colic

OBJECTIVE: To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data. ANIMALS: 765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals. PROCEDURE: Serum concentrations of SAA and LBP were determined by immunoturbidometric and dot-blot assays, respectively. RESULTS: SAA and LBP concentrations were determined for 718 and 765 horses with colic, respectively. Concentrations of SAA were significantly higher in nonsurvivors than in survivors, and horses with enteritis or colitis and conditions characterized by chronic inflammation (eg, abdominal abscesses, peritonitis, or rectal tears) had SAA concentrations significantly greater than those for horses with other conditions. Serum concentrations of LBP did not correlate with outcome, disease process, or portion of the gastrointestinal tract affected. CONCLUSIONS AND CLINICAL RELEVANCE: Circulating concentrations of SAA were significantly higher at admission in horses with colic attributable to conditions having a primary inflammatory cause (eg, enteritis, colitis, peritonitis, or abdominal abscesses) and were higher in horses that failed to survive the episode of colic, compared with concentrations in horses that survived. Serum concentrations of LBP did not correlate with survival. Analysis of these findings suggests that evaluation of SAA concentrations may be of use in identifying horses with colic attributable to diseases that have inflammation as a primary component of pathogenesis.     

Multiple dose pharmacokinetics and acute safety of piroxicam and cimetidine in the cat

The purpose of this study was to evaluate the multiple dose pharmacokinetics and acute safety of piroxicam and cimetidine alone and in combination in cats. Seven healthy cats were included in this randomized-crossover study. The cats were assigned to groups designated to receive cimetidine alone (15 mg/kg, p.o., q12 h), piroxicam alone (0.3 mg/kg, p.o., q24 h), and piroxicam combined with cimetidine (both at aforementioned doses). The cats were dosed for 10 days followed by at least a 2-week washout period between trials. Serial blood samples were collected following the first and last doses and analyzed utilizing a high-performance liquid chromatography with mass spectrometry detection (LC/MS) assay. Pharmacokinetic parameters were determined using noncompartmental analysis. Endoscopic evaluation of the gastric mucosa was performed and serum urea nitrogen (SUN), creatinine, alkaline phosphatase (ALP), and alanine transaminase (ALT) activities were evaluated. There were not a clinically relevant difference between the pharmacokinetic parameters of piroxicam administered alone or in combination with cimetidine after either the first or last dose. Gastric ulcers were not observed in any cats although gastric erosions were. The SUN, creatinine, ALP, and ALT activities remained within reference ranges for all cats. It appears that once daily, short-term use of piroxicam alone and in combination with cimetidine in cats is relatively safe based on the parameters evaluated in this study. However, further studies are necessary to determine the long-term gastrointestinal safety of piroxicam.