Canine mast cell tumors: correlation of apoptosis and proliferation markers with prognosis

The Patnaik histologic grading system is commonly used to predict the behavior of cutaneous mast cell tumors (MCTs) in dogs, but it is less useful for grade 2 MCTs because they exhibit considerable variation in biological behavior. In this retrospective study, immunohistochemical staining for Ki-67, proliferating cell nuclear antigen (PCNA), and survivin and a standardized argyrophilic staining of nucleolar organizer regions (AgNOR) protocol were performed on 121 archived paraffin-embedded specimens of canine cutaneous MCTs, for which clinical follow-up data were available. Cox regression models indicated that the Ki-67 score (hazard ratio, 1.92; P < .001) and mean AgNOR score (hazard ratio, 2.57; P < .001) were significantly associated with Patnaik grade and survival time. A binary Ki-67 variable (cutoff point Ki-67 score = 1.8) was a significant predictor of survival for dogs with grade 2 MCTs. The estimated 1-, 2-, and 3-year survival probabilities for dogs with grade 2 MCTs and Ki-67 scores less than 1.8 were 0.92, 0.86, and 0.77, respectively (SEs, 0.08, 0.14, and 0.23, respectively; median not estimable). The corresponding survival probabilities for dogs with grade 2 MCTs and Ki-67 scores higher than 1.8 were 0.43, 0.21, and 0.21, respectively (SEs, 0.19, 0.18, and 0.18, respectively; median survival time, 395 days). No significant association was identified between survival and survivin score or PCNA score. This study shows that both mean AgNOR score and Ki-67 score are prognostic markers for canine MCTs. The Ki-67 score can be used to divide Patnaik grade 2 MCTs into 2 groups with markedly different expected survival times.     

PIN proteins perform a rate-limiting function in cellular auxin efflux

Intercellular flow of the phytohormone auxin underpins multiple developmental processes in plants. Plant-specific pin-formed (PIN) proteins and several phosphoglycoprotein (PGP) transporters are crucial factors in auxin transport-related development, yet the molecular function of PINs remains unknown. Here, we show that PINs mediate auxin efflux from mammalian and yeast cells without needing additional plant-specific factors. Conditional gain-of-function alleles and quantitative measurements of auxin accumulation in Arabidopsis and tobacco cultured cells revealed that the action of PINs in auxin efflux is distinct from PGP, rate-limiting, specific to auxins, and sensitive to auxin transport inhibitors. This suggests a direct involvement of PINs in catalyzing cellular auxin efflux.     

Retrospective study of fever in dogs: laboratory testing, diagnoses and influence of prior treatment

OBJECTIVES: To analyse the demographic information of dogs referred for investigation of fever, to determine the usefulness of various diagnostic investigations and to assess the effect of treatment before referral on the presence of fever at referral, the duration of the investigation and the ability to reach a final diagnosis. METHODS: The clinical records of 66 dogs, in which fever was part of the clinical signs documented by the referring veterinary surgeon, were reviewed. The effects of treatment 24 hours before referral on temperature at initial consultation and on time to diagnosis were evaluated. The effect of body temperature at initial consultation on cost and on time to diagnosis was also determined. The effect of insurance on costs incurred was assessed. The utility of different diagnostic investigations was recorded, and cases were classified according to the final diagnosis. RESULTS: Only 34.8 per cent of dogs were diagnosed with immune-mediated disease, with most frequent diagnoses being steroid-responsive meningitis and polyarthritis. Treatment 24 hours before referral significantly increased the time to diagnosis (P = 0.004) and affected the presence of fever at referral (P = 0.006). Insurance status did not significantly affect cost incurred by the owner. CLINICAL SIGNIFICANCE: This study documents a high incidence of immune-mediated disease in dogs referred for investigation of fever. It also documents a higher incidence of inflammatory central nervous system disease in febrile dogs than that reported previously. Of the diagnostic modalities employed in the majority of cases, radiography, cytology and bacteriological and fungal cultures (fluids/tissues) were the most useful. It is suggested that treatment is withdrawn or withheld before commencing diagnostic investigation of fever.     

Analysis of canine and feline blood samples using the Kuadro in-house wet-reagent chemistry analyser

OBJECTIVES: Kuadro is a new wet-reagent biochemistry analyser that is available for in-house use. The aim of this study was to compare the results produced by this analyser with those obtained by a wet-reagent analyser (KoneLab 30i) that served as the reference instrument. METHODS: Blood samples from 80 clinical cases (40 dogs and 40 cats) were analysed for urea, creatinine, total proteins, albumin, glucose, cholesterol, alanine aminotransferase, alkaline phosphatase, total bilirubin, amylase, total calcium, and phosphate using both the reference and Kuadro instruments. RESULTS: Kuadro performed very well on canine and feline samples, showing clinically acceptable correlations (r value) (canine/feline) for urea (0.99/0.97), creatinine (0.99/0.98), total proteins (0.95/0.97), albumin (0.98/0.90), glucose (0.99/0.99), cholesterol (0.99/0.99), alanine aminotransferase (1.00/0.99), alkaline phosphatase (0.96/0.99), total bilirubin (1.00/1.00), amylase (0.98/0.96), and phosphate (0.91/0.92). The correlation for total calcium measurements was clinically unacceptable (0.78/0.83). CLINICAL SIGNIFICANCE: Urea, creatinine, albumin, glucose, cholesterol, alanine aminotransferase, and phosphate Kuadro values can be used interchangeably with those generated by the reference analyser. Alkaline phosphatase, amylase, and total proteins Kuadro values cannot be used interchangeably, as Kuadro overestimated alkaline phosphatase and amylase and underestimated total protein measurements. Kuadro significantly underestimated total calcium concentrations due to the shorter incubation time used by the Kuadro analyser compared with the incubation time used in the reference analyser assay system.     

Comparison of methods used to diagnose generalized inflammatory disease in manatees (Trichechus manatus latirostris).

Manatees (Trichechus manatus latirostris) are afflicted with inflammatory and infectious disease secondary to human interaction, such as boat strike and entanglement, as well as "cold stress syndrome" and pneumonia. White-blood-cell count and fever, primary indicators of systemic inflammation in most species, are insensitive in diagnosing inflammatory disease in manatees. Acute phase-response proteins, such as haptoglobin and serum amyloid A, have proven to be sensitive measures of inflammation/infection in domestic large animal species. This study assessed diagnosis of generalized inflammatory disease by different methods including total white-blood-cell count, albumin: globulin ratio, gel electrophoresis analysis, C-reactive protein, alpha, acid glycoprotein, haptoglobin, fibrinogen, and serum amyloid A. Samples were collected from 71 apparently healthy and 27 diseased animals during diagnostic medical examination. Serum amyloid A, measured by ELISA, followed by albumin:globulin ratio, measured by plasma gel electrophoresis, were most sensitive in diagnosing inflammatory disease, with diagnostic sensitivity and specificity of approximately 90%. The reference interval for serum amyloid A is <10-50 microg/ml with an equivocal interval of 51-70 microg/ml. The reference interval for albumin:globulin ratio by plasma gel electrophoresis is 0.7-1.1. Albumin: globulin ratio, calculated using biochemical techniques, was not accurate due to overestimation of albumin by bromcresol green dye-binding methodology. Albumin:globulin ratio, measured by serum gel electrophoresis, has a low sensitivity of 15% due to the lack of fibrinogen in the sample. Haptoglobin, measured by hemoglobin titration, had a reference interval of 0.4-2.4 mg/ml, a diagnostic sensitivity of 60%, and a diagnostic specificity of 93%. The haptoglobin assay is significantly affected by hemolysis. Fibrinogen, measured by heat precipitation, has a reference interval of 100-400 mg/dl, a diagnostic sensitivity of 40%, and a diagnostic specificity of 95%.     

The cardiopulmonary effects of anesthetic induction with isoflurane,ketamine‐diazepam or propofol‐diazepam in the hypovolemic dog

ObjectiveTo evaluate and compare the cardiopulmonary effects of induction of anesthesia with isoflurane (Iso), ketamine–diazepam (KD), or propofol–diazepam (PD) in hypovolemic dogs.Study designProspective randomized cross–over trial.AnimalsSix healthy intact, mixed breed, female dogs weighing 20.7 ± 4.2 kg and aged 22 ± 2 months.MethodsDogs had 30 mL kg^?1 of blood removed at a rate of 1.5 mL kg^?1 minute^?1 under isoflurane anesthesia. Following a 30–minute recovery period, anesthesia was reinduced. Dogs were assigned to one of three treatments: isoflurane via facemask using 0.5% incremental increases in the delivered concentration every 30 seconds, 1.25 mg kg^?1 ketamine and 0.0625 mg kg^?1 diazepam intravenously (IV) with doses repeated every 30 seconds as required, and 2 mg kg^?1 propofol and 0.2 mg kg^?1 diazepam IV followed by 1 mg kg^?1 propofol increments IV every 30 seconds as required. Following endotracheal intubation all dogs received 1.7% end–tidal isoflurane in oxygen. Cardiopulmonary variables were recorded at baseline (before induction) and at 5 or 10 minute intervals following endotracheal intubation.ResultsInduction time was longer in Iso (4.98 ± 0.47 minutes) compared to KD (3.10 ± 0.47 minutes) or PD (3.22 ± 0.45 minutes). To produce anesthesia, KD received 4.9 ± 2.3 mg kg^?1 ketamine and 0.24 ± 0.1 mg kg^?1 diazepam, while PD received 2.2 ± 0.4 mg kg^?1 propofol and 0.2 mg kg^?1 diazepam. End–tidal isoflurane concentration immediately following intubation was 1.7 ± 0.4% in Iso. Arterial blood pressure and heart rate were significantly higher in KD and PD compared to Iso and in KD compared to PD. Arterial carbon dioxide partial pressure was significantly higher in PD compared to KD and Iso immediately after induction.Conclusions and clinical relevanceIn hypovolemic dogs, KD or PD, as used in this study to induce anesthesia, resulted in less hemodynamic depression compared to isoflurane.