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21.
OBJECTIVE: To determine the functionality of canine anti-Malassezia IgE via the passive transfer of immediate hypersensitivity localized to the skin (ie, cutaneous anaphylaxis) from atopic dogs with dermatitis attributable to overgrowth of Malassezia pachydermatis (Malassezia dermatitis [MD]) to healthy recipient dogs by use of the Prausnitz-Küstner (P-K) technique. ANIMALS: 7 clinically normal dogs, 32 atopic dogs with MD, serum from 11 atopic dogs with MD, and 3 healthy dogs without prior sensitization to M pachydermatis. PROCEDURE: Serum from atopic dogs with MD was used for P-K tests in 3 clinically normal recipient dogs. Serial dilutions of untreated, heat-inactivated, IgE-absorbed, and bovine serum albumin (BSA)-absorbed (control) aliquots of serum were injected ID in triplicate for dermal sensitization. Twenty-four, 48, and 72 hours later, a crude extract of M pachydermatis was injected ID into the sites used for sensitization injections, and immediate hypersensitivity reactions were graded on a 4-point scale. RESULTS: Untreated serum caused P-K reactivity beginning 24 hours after passive sensitization and persisting through 72 hours (titers, 1:32 to 1:64). Heat inactivation and IgE-absorption of serum eliminated P-K reactivity, whereas treatment of serum with BSA did not. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of P-K test results supports the passive transfer of cutaneous anaphylaxis by anti-Malassezia IgE and indicates it is functional in type-1 hypersensitivity reactions of atopic dogs with MD. Reduction or blockade of anti-Malassezia IgE in atopic dogs with MD may provide better clinical control of the disease.  相似文献   
22.
OBJECTIVE: To characterize the signalment, clinical signs, biological behavior, and response to treatment of carcinoma of the apocrine glands of the anal sac in dogs. DESIGN: Retrospective study. ANIMALS: 113 dogs with histologically confirmed carcinoma of the apocrine glands of the anal sac. PROCEDURE: Data on signalment, clinical signs, and staging were reviewed and analyzed along with treatment modality for potential association with survival time. RESULTS: Sex distribution was approximately equal (54% female, 46% male). One hundred four dogs underwent treatment consisting of surgery, radiation therapy, chemotherapy, or multimodal treatment. Median survival for treated dogs was 544 days (range, 0 to 1,873 days). Dogs treated with chemotherapy alone had significantly shorter survival (median, 212 days) than those receiving other treatments (median, 584 days). Dogs not treated with surgery had significantly shorter survival (median, 402 days) than those that underwent surgery as part of their treatment (median, 548 days). Dogs with tumors > or = 10 cm2 had significantly shorter survival (median, 292 days) than dogs with tumors < 10 cm2 (median, 584 days). Hypercalcemia was identified in 27% (n = 29) of dogs, and those dogs had significantly shorter survival (median, 256 days), compared with those that were normocalcemic (median, 584 days). Dogs with pulmonary metastasis had significantly shorter survival (median, 219 days) than dogs without evidence of pulmonary metastasis (median, 548 days). CONCLUSIONS AND CLINICAL RELEVANCE: Unlike most previous reports, this study revealed an approximately equal sex distribution, and results suggest a more favorable prognosis.  相似文献   
23.
A 4-year-old llama had an aggressive, multiloculated, expansile bone lesion involving the rostral mandible. The mandibular lesion was imaged using radiography and computed tomography. Antemortem diagnosis of an ossifying fibroma was made histologically. Postmortem findings showed the lesion to be limited to the mandible. Final diagnosis was ameloblastic odontoma.  相似文献   
24.
An adenovirus was isolated from intestinal samples of two long-tailed ducks (Clangula hyemalis) collected during a die-off in the Beaufort Sea off the north coast of Alaska in 2000. The virus was not neutralized by reference antiserum against known group I, II, or III avian adenoviruses and may represent a new serotype. The prevalence of the virus was determined in live-trapped long-tailed ducks at the mortality site and at a reference site 100 km away where no mortality was observed. Prevalence of adenovirus antibodies in serum samples at the mortality site was 86% compared to 10% at the reference site. Furthermore, 50% of cloacal swabs collected at the mortality site and only 7% of swabs from the reference site were positive for adenoviruses. In 2001, no mortality was observed at either of the study areas, and virus prevalence in both serum and cloacal samples was low, providing further evidence that the adenovirus was linked to the mortality event in 2000. The virus was used to infect long-tailed ducks under experimental conditions and resulted in lesions previously described for avian adenovirus infections and similar to those observed in long-tailed duck carcasses from the Beaufort Sea. The status of long-tailed ducks has recently become a concern in Alaska due to precipitous declines in breeding populations there since the mid-1970s. Our findings suggest that the newly isolated adenovirus is a disease agent and source of mortality in long-tailed ducks, and thus could be a contributing factor in population declines.  相似文献   
25.
OBJECTIVE: To evaluate lipopolysaccharide (LPS)-induced activation of equine neutrophils in blood. SAMPLE POPULATION: Blood samples from 5 healthy adult Thoroughbreds. PROCEDURES: Neutrophil integrin (CD11/CD18) expression, size variation, degranulation, and deformability were measured with and without incubation with LPS. Time and concentration studies were done. The mechanism of endotoxin-induced neutrophil activation was investigated by inactivating complement or preincubating neutrophils with inhibitors of tumor necrosis factor-alpha (TNF-alpha) synthesis, prostaglandin-leukotriene synthesis, or platelet-activating factor. RESULTS: Incubation of equine neutrophils with LPS increased cell surface expression of CD11/CD18, decreased neutrophil deformability, increased and decreased neutrophil size, and induced neutrophil degranulation. The LPS-induced neutrophil activation was attenuated by addition of inhibitors of TNF-alpha and prostaglandin-leukotriene synthesis. CONCLUSIONS AND CLINICAL RELEVANCE: Equine neutrophils are readily activated in vitro by LPS, resulting in increased expression of integrin adhesion molecules, decreased deformability, variation in neutrophil size, and degranulation. The tests used to detect activated neutrophils in this study may be useful in detecting in vivo neutrophil activation in horses with sepsis and endotoxemia.  相似文献   
26.
OBJECTIVE: To determine the efficacy of triamcinolone acetonide topical solution (TTS) in dogs for use in reduction of clinical signs of pruritic inflammatory skin diseases of a known or suspected allergic basis and to evaluate adverse effects associated with TTS administration. ANIMALS: 103 pruritic adult dogs with known or suspected allergic skin disease. PROCEDURE: Dogs were treated for 4 weeks with TTS or with vehicle solution (control dogs) in a multiple-center study. Clinical signs were scored by owners and by examining veterinarians before and after treatment. Blood samples obtained before and after treatment were subjected to routine hematologic and serum biochemical analyses. RESULTS: Treatment success, as defined by an improvement of at least 2 of 6 grades in overall clinical score, was evident in 35 of 52 (67%) TTS-treated dogs (mean improvement, 1.98) and 12 of 51 (24%) control dogs (mean improvement, 0.29). For several criteria, TTS was significantly more effective than vehicle in reducing clinical signs. Minor alterations in hematologic determinations in TTS-treated dogs were limited to slightly lower total leukocyte, lymphocyte, and eosinophil counts after treatment. Minor adverse effects were reported by owners in 6 of 52 (12%) TTS-treated and 9 of 51 (18%) control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Triamcinolone used as a spray solution at a concentration approximately one-sixth the concentration of triamcinolone topical preparations currently available for veterinary use is effective for short-term alleviation of allergic pruritus in dogs. Adverse effects are few and mild and, thus, do not preclude prolonged treatment with the solution.  相似文献   
27.
OBJECTIVE: To determine the effect of vaccination on serum concentrations of total and antigen-specific IgE in dogs. ANIMALS: 20 female Beagles. PROCEDURE: Groups of 5 dogs each were vaccinated repeatedly between 8 weeks and 4 years of age with a multivalent and rabies vaccine, a multivalent vaccine only, or a rabies vaccine only. A fourth group of 5 dogs served as unvaccinated controls. Serum concentrations of total immunoglobulins and antigen-specific IgE were determined following vaccination. RESULTS:-The multivalent vaccine had little effect on serum total IgE concentrations. The concentration of IgE increased slightly following vaccination for rabies at 16 weeks and 1 year of age and increased greatly after vaccination at 2 and 3 years of age in most dogs, with a distinct variation between individual dogs. Vaccination had no effect on serum concentrations of IgA, IgG, and IgM as measured at 2 and 3 years of age. The rabies vaccine contained aluminum adjuvant in contrast to the multivalent vaccine. An increase of IgE that was reactive with vaccine antigens, including bovine serum albumin and bovine fibronectin, was detected in some of the dogs vaccinated for rabies. There was no significant correlation between serum concentrations of total IgE and antigen-specific IgE following vaccination. Serum total IgE concentration rapidly returned to preimmunization concentrations in most dogs, but high concentrations of antigen-specific IgE persisted. CONCLUSIONS AND CLINICAL RELEVANCE: Vaccination of dogs for rabies increases serum concentrations of total IgE and induces IgE specific for vaccine antigens, including tissue culture residues. Vaccination history should be considered in the interpretation of serum total IgE concentrations.  相似文献   
28.
OBJECTIVE: To evaluate diagnostic utility of a commercially available immunoassay for assessing adequacy of passive transfer of immunity in neonatal calves. DESIGN: Prospective study. ANIMALS: 123 calves. PROCEDURE: Blood and serum samples were obtained from the calves prior to 2 weeks of age. The immunoassay was performed, along with refractometry and an 18% sodium sulfite turbidity test. Serum IgG concentration was determined with a radial immunodiffusion assay. Sensitivity and specificity of the immunoassay, refractometry, and the sodium sulfite test were calculated by comparing results with results of the radial immunodiffusion assay. RESULTS: Sensitivity and specificity of the blood IgG immunoassay were 0.93 and 0.88, respectively, compared with 1.00 and 0.53 for the sodium sulfite test. For refractometry, sensitivity and specificity were 0.71 and 0.83, respectively, when a serum total solids concentration of 5.2 g/dl was used as the cutoff between positive and negative test results. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the immunoassay performs well in detecting calves with inadequate passive transfer of immunity.  相似文献   
29.
OBJECTIVES: To assess the effect of increasing serum lithium concentrations on lithium dilution cardiac output (LiDCO) determination and to determine the ability to predict the serum lithium concentration from the cumulative lithium chloride dosage. ANIMALS: 10 dogs (7 males, 3 females). PROCEDURE: Cardiac output (CO) was determined in anesthetized dogs by measuring LiDCO and thermodilution cardiac output (TDCO). The effect of the serum lithium concentration on LiDCO was assessed by observing the agreement between TDCO and LiDCO at various serum lithium concentrations. Also, cumulative lithium chloride dosage was compared with the corresponding serum lithium concentrations. RESULTS: 44 paired observations were used. The linear regression analysis for the effect of the serum lithium concentration on the agreement between TDCO and LiDCO revealed a slope of -1.530 (95% confidence interval [CI], -2.388 to -0.671) and a y-intercept of 0.011 (r2 = 0.235). The linear regression analysis for the effect of the cumulative lithium chloride dosage on the serum lithium concentration revealed a slope of 2.291 (95% CI, 2.153 to 2.429) and a y-intercept of 0.008 (r2 = 0.969). CONCLUSIONS AND CLINICAL RELEVANCE: The LiDCO measurement increased slightly as the serum lithium concentration increased. This error was not clinically relevant and was minimal at a serum lithium concentration of 0.1 mmol/L and modest at a concentration of 0.4 mmol/L. The serum lithium concentration can be reliably predicted from the cumulative lithium dosage if lithium chloride is administered often within a short period.  相似文献   
30.
OBJECTIVE: To determine antidermatophyte immunologic effects of an experimental combined live-inactivated dermatophytosis vaccine (CLIDV) and a commercial inactivated dermatophytosis vaccine (IDV) in cats and to evaluate adverse effects associated with administration of these vaccines. ANIMALS: 20 healthy juvenile domestic shorthair cats. PROCEDURE: Cats were injected with 2 doses of CLIDV at the standard dosage or 1 dose of CLIDV at 10 times the standard dosage; IDV was administered at the manufacturer-recommended dosage. Cats were observed for illness and reactions at inoculation sites. Periodically, samples were obtained for fungal culture, lymphocyte blastogenesis test (LBT) as an indicator of cell-mediated immunity against dermatophyte antigens, and antidermatophyte IgG titers. Following vaccination, cats were challenge-exposed by topical application of Microsporum canis macroconidia and examined weekly for clinical signs of dermatophytosis. RESULTS: of 10 cats given CLIDV developed focal crusts at the injection site that resolved without treatment; these were areas of dermatophyte infection with the vaccine strain. Antidermatophyte IgG titers increased significantly with all vaccination protocols. Cellular immunity against M canis increased slightly and variably during the vaccination period and did not differ significantly between vaccinated and control cats. All cats developed dermatophyte infection after challenge exposure. Vaccination with CLIDV or IDV was associated with slightly reduced severity of initial infection. CONCLUSIONS AND CLINICAL RELEVANCE: Noculation with IDV or CLIDV did not provide prophylactic immunity against topical challenge exposure with M canis. Inoculation with either vaccine did not provide a more rapid cure of an established infection.  相似文献   
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