Abdominal CT evaluation of the liver and spleen for staging mast cell tumors in dogs yields nonspecific results

Canine mast cell tumor staging is commonly performed using abdominal ultrasonography and fine‐needle aspiration cytology of masses, lymph nodes, and hepatic and splenic parenchyma. Computed tomography is used for abdominal, thoracic, or whole body imaging in staging mast cell tumors in the authors’ institution enabling evaluation of multiple body areas in one examination. The aim of this study was to compare the CT examinations acquired for staging of mast cell disease to their subsequent liver and spleen cytology findings. Medical records of dogs with primary mast cell tumors that underwent abdominal CT and concurrent liver and spleen aspirates were reviewed. The CT examinations were evaluated for attenuation, size, and margination of the liver and spleen. The relationship between CT findings and cytology results was analyzed. Forty‐nine dogs matched the inclusion criteria: five of forty‐nine dogs with cutaneous mast cell tumors were positive for metastasis from liver and/or spleen aspirates. Of the five dogs with cytological evidence of liver or spleen metastasis, four had normal CT liver attenuation and size, one dog had concurrent primary hepatocellular neoplasia, four dogs had abnormal splenic parenchyma (two nodular and two diffuse heterogeneity), and one dog had a normal attenuation of the spleen. In four dogs, the spleen was subjectively enlarged. Computed tomographic evaluation of the liver showed no consistent pattern associated with mast cell metastasis and did not predict cytology results. Multifocal splenic hypoattenuating lesions more commonly coincided with mast cell metastasis. Sampling of the liver and spleen remains to be considered in the absence of abnormal CT findings for full staging.     

The prevalence of Dirofilaria immitis in dogs in Sydney

Four hundred and four dogs from 9 pounds in Sydney were examined for circulating microfilariae and antigens of Dirofilaria immitis. One hundred of these were also examined post mortem for adult heartworms. The prevalence of infection in the 404 dogs as shown by serology was 11.4%, and 5.9% had circulating microfilariae of D immitis. Adult heartworms were present in 15 of 100 dogs. Dipetalonema reconditum microfilariae were present in 3.7% of dogs. Dirofilariosis is still a common and important parasite of dogs in the Sydney region and chemoprophylaxis is recommended.     

Vaginal isolation of beta‐haemolytic Streptococcus from bitches with and without neonatal deaths in the litters

The aim of the study was to identify beta‐haemolytic streptococci in the vagina of bitches who had delivered healthy litters and bitches who had delivered litters in which neonatal deaths occurred. Fifty‐one bitches divided into two groups were used. Group 1 (G1) included 28 bitches that had delivered healthy litters and group 2 (G2) included 23 bitches that had delivered puppies who died in the neonatal period. Two vaginal samples were taken, one in proestrus and the other at the end of gestation (EG). Beta‐haemolytic Streptococcus (BS) was isolated from 16 bitches (57%) in G1 and from 21 bitches (91%) in G2. The bacteriological cultures, serological tests (Streptex^®) and PCR assay allowed identification of Streptococcus canis and Streptococcus dysgalactiae in G1 and G2. Ultramicroscopic studies allowed the observation of M Protein and capsules in strains of S. dysgalactiae and S. canis in G1 and G2. The S. canis strains isolated from G2 showed thicker capsules than S. canis strains isolated from G1 (234 ± 24.2 vs 151.23 ± 28.93 nm; p < .001.). No differences were observed in capsule thickness between strains of S. dysgalactiae isolated from G1 and G2 (210 ± 13.54 vs 211.66 ± 19.67 nm; p > .70). All strains of beta‐haemolytic Streptococcus isolated were penicillin sensitive. Penicillin was administered from EG to 5 days post‐partum in 10 G2 females with isolation of BS (G2A). Saline solution was administered in eleven G2 females with isolation of BS (G2B). Ninety per cent of the puppies survived in G2A and 25% survived in G2B. Our results suggest BS is involved in canine neonatal deaths.     

Clinical investigation of a point-of-care blood ammonia analyzer

BACKGROUND: Hyperammonemia has frequently been implicated in the pathogenesis of hepatic encephalopathy. Blood ammonia determination requires minimal delay between sampling and analysis for accurate results. OBJECTIVES: The aim of this study was to investigate the PocketChem BA, a new point-of-care (POC) blood ammonia analyzer for clinical use by determining machine precision, linearity, repeatability, and accuracy. METHODS: Coefficients of variation were determined by repeated measurement of 2 control solutions. Linearity was investigated by testing serial dilutions of a stock solution. For accuracy, samples from clinical cases were used to compare the results on the PocketChem BA with those obtained using an enzymatic reference method for canine plasma. Canine and feline patients were consecutively enrolled if blood ammonia was assayed and samples could be analyzed shortly after collection. Classification of results (as normal or high, using 100 micromol/L as a cutoff value), Bland-Altman and Deming regression plots, and intraclass correlation coefficients were used to compare the methods. Stability of samples and test strips also was assessed over time. RESULTS: Coefficients of variation were 10.6% and 4.8% for low and high controls, respectively. Concentrations of ammonia in diluted stock solutions correlated positively with mean measured concentrations (Pearson coefficient 0.988, P<.001). Of the 54 samples obtained from 38 dogs and 4 cats, 41 had ammonia concentrations within the readable range. Results from the POC analyzer and the reference method were correlated positively (intraclass coefficient 0.800, 95% confidence interval 0.655-0.888), with the POC analyzer having negative constant and proportional biases. The methods agreed in the classification of 45/54 (83.3%) samples, with 7 false negative results on the POC analyzer. Results of repeated sample and strip analyses at 1 and 24 hours were significantly different (P<.05) from those at 0 hour. CONCLUSIONS: The PocketChem BA has acceptable precision, adequate linearity, and satisfactory agreement with a reference method, but negative constant and proportional biases. The POC analyzer may be suitable for clinical use in patients suspected of having hepatic encephalopathy, using a lower reference limit of 60 mumol/L to decrease false negative results.     

Plasma and liver concentrations of aP-tocopherol in weaner sheep after vitamin E supplementation

Changes in the plasma and liver concentrations of alpha-tocopherol in sheep kept in an animal house, grazed on pasture, grazed on pasture and fed an oat/lupin grain supplement, or grazed on toxic lupin stubble were monitored following no, oral or intramuscular administration of alpha-tocopherol. It was concluded that intramuscular administration was most effective because it caused longer periods of elevated plasma alpha-tocopherol concentrations in most situations investigated and consistently higher concentrations of alpha-tocopherol in the liver, compared to oral administration. The dose rates of alpha-tocopherol given, the vehicle for alpha-tocopherol in the injectable preparation, the different diets consumed and the concurrent occurrence of lupinosis all influenced the results. In spite of this a significant positive correlation existed between the terminal liver and plasma alpha-tocopherol concentrations.     

Co-expression of a NADPH:P450 reductase enhances CYP71A10-dependent phenylurea metabolism in tobacco

A soybean cytochrome P450 monooxygenase, designated CYP71A10, catalyzes the oxidative N-demethylation or ring methyl hydroxylation of a variety of phenylurea herbicides. The ectopic expression of CYP71A10 in tobacco was previously shown to be an effective means of enhancing whole plant tolerance to the compounds linuron and chlortoluron. Because P450 enzymes require ancillary proteins to catalyze the transfer of electrons from NADPH to the functional heme group of the P450, it is possible that the endogenous levels of these companion proteins may be insufficient to support the optimal activation of a highly expressed recombinant P450. In the present report, we have generated transgenic tobacco that simultaneously express CYP71A10 and a soybean P450 reductase. Transformed plants that express both CYP71A10 and the P450 reductase demonstrated 20-23% higher metabolic activity against phenylurea herbicides than control plants expressing CYP71A10 alone. These results suggest that herbicide tolerance strategies based on the expression of P450 genes may require concomitant expression of a cognate electron transport partner to fully exploit the herbicide metabolic capacity of the P450.     

Optimized Monier-Williams method for determination of sulfites in foods: collaborative study

A collaborative study was conducted of the Food and Drug Administration (FDA)-optimized Monier-Williams method for determining sulfites in foods. Twenty-one industry and government laboratories participated in the study, which was jointly sponsored by the National Food Processors Association and FDA. Familiarization samples were shipped to each collaborator. Collaborators were permitted to proceed to the main study only after they demonstrated ability to perform the method to ensure that the study tested the performance of the method itself and not that of the individual laboratories. The study design involved 3 food matrixes (hominy, fruit juice, and protein [seafood]). Each matrix was prepared at 3 sulfite levels--the regulatory level, half the regulatory level, twice the regulatory level--and as a blank. All test samples were analyzed as blind duplicates, which gave each collaborator a total of 24 test portions. Collaborative recoveries gave a reproducibility (among-laboratories) coefficient of variation that ranged from 15.5 to 26.6% for sulfite determined as SO2 by weight in the 3 foods at the 10 ppm level. The optimized Monier-Williams method has been approved interim official first action to replace the AOAC modified Monier-Williams method, 20.123-20.125.     

Green turtle migrations in the Hawaiian archipelago

In order to understand better the natural history and conservation status of the unique land-basking Hawaiian green turtle population (Chelonia sp.), intensive tagging studies were conducted at French Frigate Shoals (24°N 160 °W), a wildlife sanctuary comprising the only aggregate breeding site remaining in the 2600 km long Archipelago. Additionally, newly captured Chelonia, as well as individuals held for extended periods in display aquaria, were tagged and released around the large islands in the southeast. Tag recoveries of adults identified during the 1973 and 1974 nesting seasons documented migrations from French Frigate Shoals to the islands of Kauai, Oahu and Maui, distances of 713, 936 and 1069 km to the southeast, respectively, and to French Frigate Shoals from Lisianski Island and Pearl and Hermes Reef, distances of 834 and 1075 km to the northwest, respectively. A captive-held female released off Niihau travelled 658 km to French Frigate Shoals where nesting was recorded. Other animals released from captivity showed movement between the large islands, while those released shortly after capture remained in the same coastal area for up to 11 months. Combined results from the present study and previous intermittent taggings made since 1961 by Federal and State wildlife management personnel indicated that breeding colony members are derived from widely separated feeding areas within the archipelago and appear to be reproductively isolated from other Pacific Chelonia. Northwestern areas of the archipelago are thought to serve as important migratory stations for early life stage development.