Rush allergen specific immunotherapy protocol in feline atopic dermatitis: a pilot study of four cats

Rush immunotherapy has been shown to be as safe as conventional immunotherapy in canine atopic patients. Rush immunotherapy has not been reported in the feline atopic patient. The purpose of this pilot study was to determine a safe protocol for rush immunotherapy in feline atopic patients. Four atopic cats diagnosed by history, physical examination and exclusion of appropriate differential diagnoses were included in the study. Allergens were identified via liquid phase immunoenzymatic testing (VARL: Veterinary Allergy Reference Labs, Pasadena, CA). Cats were premedicated with 1.5 mg triamcinolone orally 24 and 2 h prior to first injection and 10 mg hydroxyzine PO 24, 12 and 2 h prior to first injection. An intravenous catheter was placed prior to first injection. Allergen extracts (Greer Laboratories, Lenoir, North Carolina) were all administered subcutaneously at increasing protein nitrogen units (pnu) every 30 minutes for 5 h to maintenance dose of 15,000 pnus ml-1. Vital signs were assessed every 15 minutes. Two cats developed mild pruritus and the subsequent injection was delayed 30 minutes. No changes in either cat's vital signs were noted, nor was there any further pruritus. All four cats successfully completed rush immunotherapy. Two cats developed a dermal swelling on the dorsal neck one week later. In these four cats, this protocol appeared to be a safe regimen to reach maintenance therapy. A larger sample of feline patients is needed to determine the incidence of adverse reactions and to follow the success of ASIT based upon this method of induction.     

An animal model for interface tissue formation in cemented hip replacements

OBJECTIVE: To create a model in sheep for investigation of early changes related to the formation of an interface membrane in hip prosthesis. STUDY DESIGN: Experimental study. ANIMALS: Twenty-four female adult Swiss Alpine sheep. METHODS: Sheep were divided into 2 groups of 12 for unilateral cemented total hip arthroplasty. In Group I, the prosthesis was fixed with retrograde cement gun injection to achieve a complete cement mantle, whereas in Group II a primary cement mantle defect was produced. Groups I and II were further divided into 2 sub-groups with study end points of 2 and 8.5 months after surgery. Radiographs were evaluated postoperatively and at euthanasia for migration of the femoral component and bone resorption. Histologic sections were evaluated semiquantitatively for changes in cell types and numbers, and bone reactions; and quantitatively for size of interface membrane and new bone formation. RESULTS: Radiographically, there tended to be an increase in bone resorption and periosteal bone formation throughout the femoral shaft in Group II compared with Group I, but this was only statistically significant at the region of the femoral neck (R5) at both time periods (P<.05). Semiquantitative histologic evaluation revealed significant increases (P<.05) in cellularity, numbers of fibroblasts, giant cells, macrophages, and mononuclear cells, in Group II primarily at 2 months after surgery. This was also true for interface membrane formation and bone remodeling. Quantitative data showed an increased in the size of the interface membrane and area of bone formation at 8.5 months in Group II. CONCLUSIONS: The cement defect model offered controlled and repeatable production of an interface membrane. The results suggest that a primary cement mantle defect could be a possible trigger for implant instability, eliciting a cascade of biomechanical and molecular events in bone tissue leading to aseptic loosening. CLINICAL RELEVANCE: The results show the effect of defects in the cement mantle in promoting interface membrane formation. Long-term and biochemical studies are required to evaluate the relevance of this interface membrane formation.     

Efficacy of a long-acting formulation of ceftiofur crystalline-free acid for the treatment of naturally occurring infectious bovine keratoconjunctivitis

OBJECTIVE: To evaluate the efficacy of ceftiofur crystalline-free acid (CCFA) administered into the posterior aspect of an ear for treatment of corneal ulceration associated with naturally occurring infectious bovine keratoconjunctivitis (IBK). ANIMALS: 78 beef calves located at Sierra Foothills Field Station (SFS) and 52 calves located at a commercial dairy (CD). All calves were from 3 to 9 months old. PROCEDURE: At each site, calves were randomly allocated to 1 of 2 treatment groups by use of a block design determined by corneal ulcer size. A single dose of CCFA (6.6 mg of ceftiofur equivalents/kg, s.c.) was administered into the posterior aspect of a pinna. A second group of calves received a single dose of vehicle (0.03 mL/kg, s.c.; controls). Corneal ulcers were photographed, and clinical signs were assessed in calves every 3 to 4 days for 21 days. RESULTS: A positive treatment effect was detected at SFS. Results at the CD were inconclusive because ulcer healing occurred rapidly in control and CCFA-treated calves. At SFS, treatment with CCFA resulted in shorter mean healing times, smaller corneal ulcer surface area measurements, amelioration of ocular discharge and photophobia, and a 50% increase in the percentage of calves healed by day 14. After adjustment for initial corneal ulcer size, treatment with CCFA resulted in a 4-fold increase in the odds of corneal ulcer healing by day 14, compared with controls. CONCLUSIONS AND CLINICAL RELEVANCE: A single dose of CCFA administered into the posterior aspect of a pinna had a positive treatment effect against naturally occurring IBK in calves with corneal ulcerations.     

Effects of constant rate infusions of dexmedetomidine or MK-467 on the minimum alveolar concentration of sevoflurane in dogs

Objective

To determine the effects of low and high dose infusions of dexmedetomidine and a peripheral α₂-adrenoceptor antagonist, MK-467, on sevoflurane minimum alveolar concentration (MAC) in dogs.

Human tularaemia associated with exposure to domestic dogs—United States, 2006–2016

Dogs have been implicated in the zoonotic transmission of numerous pathogens. Whereas cats are known to transmit Francisella tularensis to humans via bite and other routes, the role of dogs in facilitating infection is much less understood. We reviewed tularaemia case investigation records collected through national surveillance during 2006–2016 to summarize those with dog involvement, characterize the nature of dog‐related exposure and describe associated clinical characteristics. Among 1,814 human tularaemia cases, 735 (41%) supplemental case investigation records were available for review; and of those, 24 (3.3%) were classified as dog‐related. Median age of patients was 51 years (range: 1–82); 54% were female. Two thirds (67%) of cases presented with ulceroglandular/glandular tularaemia; pneumonic (13%) and oropharyngeal (13%) illness occurred less frequently. Dog‐related exposures were classified as follows: direct contact via bite, scratch or face snuggling/licking (n = 12; 50%); direct contact with dead animals retrieved by domestic dogs (n = 8; 33%); and contact with infected ticks acquired from domestic dogs (n = 4; 17%). Prevention of dog‐related tularaemia necessitates enhanced tularaemia awareness and tick avoidance among pet owners, veterinarians, health care providers and the general public.     

Salmonella enterica serovar Kentucky recovered from human clinical cases in Maryland,USA (2011–2015)

Salmonella Kentucky is among the most frequently isolated S. enterica serovars from food animals in the United States. Recent research on isolates recovered from these animals suggests there may be geographic and host specificity signatures associated with S. Kentucky strains. However, the sources and genomic features of human clinical S. Kentucky isolated in the United States remain poorly described. To investigate the characteristics of clinical S. Kentucky and the possible sources of these infections, the genomes of all S. Kentucky isolates recovered from human clinical cases in the State of Maryland between 2011 and 2015 (n = 12) were sequenced and compared to a database of 525 previously sequenced S. Kentucky genomes representing 12 sequence types (ST) collected from multiple sources on several continents. Of the 12 human clinical S. Kentucky isolates from Maryland, nine were ST198, two were ST152, and one was ST314. Forty‐one per cent of isolates were recovered from patients reporting recent international travel and 58% of isolates encoded genomic characteristics similar to those originating outside of the United States. Of the five isolates not associated with international travel, three encoded antibiotic resistance genes conferring resistance to tetracycline or aminoglycosides, while two others only encoded the cryptic aac(6′)‐Iaa gene. Five isolates recovered from individuals with international travel histories (ST198) and two for which travel was not recorded (ST198) encoded genes conferring resistance to between 4 and 7 classes of antibiotics. Seven ST198 genomes encoded the Salmonella Genomic Island 1 and substitutions in the gyrA and parC genes known to confer resistance to ciprofloxacin. Case report data on food consumption and travel were, for the most part, consistent with the inferred S. Kentucky phylogeny. Results of this study indicate that the majority of S. Kentucky infections in Maryland are caused by ST198 which may originate outside of North America.     

Effects of bacterial lipopolysaccharide injection on white blood cell counts, hematological variables, and serum glucose, insulin, and cortisol concentrations in ewes fed low- or high-protein diets

Bacterial lipopolysaccharide endotoxins (LPS) elicit inflammatory responses reflective of acute bacterial infection. We determined if feeding ewes high-CP (15.5%) or low-CP (8.5%) diets for 10 d altered inflammatory responses to an intravenous bolus of 0 (control), 0.75 (L75), or 1.50 (L150) μg of LPS/kg of BW in a 2 × 3 factorial arrangement of treatments (n = 5/treatment). Rectal temperatures, heart and respiratory rates, blood leukocyte concentrations, and serum cortisol, insulin, and glucose concentrations were measured for 24 h after an LPS bolus (bolus = 0 h). In general, rectal temperatures were greater (P ≤ 0.05) in control ewes fed high CP, but LPS increased (P ≤ 0.05) rectal temperatures in a dose-dependent manner at most times between 2 and 24 h after the bolus. Peak rectal temperatures in L75 and L150 occurred 4 h after the bolus. A monophasic, dose-independent increase (P ≤ 0.023) in serum cortisol occurred from 0.5 to 24 h after the bolus, with peak cortisol at 4 h. Serum insulin was increased (P ≤ 0.016) by LPS in a dose-dependent manner from 4 to 24 h after the bolus. Insulin did not differ between control ewes fed high- and low-CP diets but was greater (P < 0.001) in L75 ewes fed low CP compared with high CP and in L150 ewes fed high CP compared with low CP. Increased insulin was not preceded by increased serum glucose. Total white blood cell concentrations were not affected (P ≥ 0.135) by LPS, but the neutrophil and monocyte fractions of white blood cells were increased (P ≤ 0.047) by LPS at 12 and 24 h and at 24 h after the bolus, respectively, and the lymphocyte fraction was increased (P = 0.037) at 2 h and decreased (P ≤ 0.006) at 12 and 24 h after the bolus. Red blood cell and hemoglobin concentrations and hematocrit (%) were increased (P ≤ 0.022) by LPS at 2 and 4 h after the bolus. Rectal temperatures and serum glucose were greater (P ≤ 0.033) in ewes fed a high-CP diet before LPS injection, but these effects were lost at and within 2.5 h of the bolus, respectively. Feeding high-CP diets for 10 d did not reduce inflammation in ewes during the first 24 h after LPS exposure but may benefit livestock by preventing acute insulin resistance when endotoxin exposure is mild.     

Decreased expression of p63, a regulator of epidermal stem cells, in the chronic laminitic equine hoof

Reasons for performing study: Abnormal epidermal stem cell regulation may contribute to the pathogenesis of equine chronic laminitis. Objective: To analyse the involvement of p63, a regulator of epidermal stem cell proliferative potential, in chronic laminitis. Methods: Epidermal tissues from skin, coronet and lamellae of the dorsal foot were harvested from 5 horses with chronic laminitis and 5 control horses. Tissues were analysed using histopathology, immunofluorescence microscopy and quantitative immunoblotting Results: Hoof lamellae of laminitic horses had a lower frequency of p63 positive cells than control lamellae, particularly in the distal region. Quantitative immunoblotting confirmed reduced p63 expression in the laminitic distal lamellar region. The decreased p63 expression in laminitic epidermal lamellae was most apparent in the abaxial region adjacent to the hoof wall and highly associated with the formation of terminally differentiated, dysplastic and hyperkeratotic epidermis in this region, whereas lamellae from control horses maintained high p63 expression throughout the axial‐abaxial axis. Conclusions: Expression of p63 in equine skin resembles that reported in other species, including man and rodents, suggesting that p63 can serve as a marker for the proliferative potential of equine epidermal stem cells. p63 expression was significantly lower in the chronic laminitic hoof than in that of control horses, suggesting laminitic hoof epithelium has more limited proliferative potential with a shift towards differentiation. This may reflect reduced activity of epidermal stem cells in laminitic hoof. It is proposed that p63 contributes to the maintenance of hoof lamellae and that misregulation of p63 expression may lead to epidermal dysplasia during lamellar wedge formation. Potential relevance: This study suggests that loss of epidermal stem cells contributes to the pathogenesis of equine laminitis. Autologous transplantation of p63‐positive epidermal stem cells from unaffected regions may have regenerative therapeutic potential for laminitic horses.     

Evaluation of 2 cement techniques for augmentation of stripped 1.5 mm screw sites in the distal metaphysis of feline radii

OBJECTIVE: To evaluate the effect of 2 cement augmentation techniques on pullout strength of 1.5 mm screws placed in stripped 1.5 mm screw sites in the distal metaphysis of feline radii. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Feline radii (21 pairs). METHODS: Treatment groups (n=4) were allocated according to a Latin square design to 4 sites in each pair of radii. Positive and negative controls were a 1.5 mm screw and a screw of the same diameter in a previously stripped screw hole, respectively. Treatment groups were a 1.5 mm screw implanted in a previously stripped screw hole after injection of polymethylmethacrylate (PMMA) or a bioresorbable calcium phosphate cement (CPC, Norian skeletal repair system (SRS)). The ultimate pullout strength was compared between groups. RESULTS: The mean (+/-SEM) pullout strength of screws augmented with either bone cement was less than that of the positive control group and greater than that of the negative control. Injection of CPC or PMMA before screw implantation increased the pullout strength of the negative control by 86.8+/-22.9% and 104.1+/-32.1%, respectively. Holding power of the positive control screws differed from these 2 groups, and was 274.8+/-39.17% higher than that of the negative control. CONCLUSION: Injection of CPC or PMMA increases but does not restore the holding power of stripped 1.5 mm diameter screws. CLINICAL RELEVANCE: The use of CPC (Norian SRS) augmentation of stripped 1.5 mm diameter screws warrants clinical investigation as it combines biomechanical results similar to PMMA with osteoconduction and resorbability.