Synovitis induced by joint lavage with hypertonic saline solutions in healthy dairy calves.

The objective of this study was to evaluate the effect of a single joint lavage with 7.2% or 15% hypertonic saline solutions (HSS) on the tarsocrural joints of healthy calves. The tarsi of 10 calves were randomly lavaged with 7.2% HSS, 15% HSS, or isotonic saline. Synovial fluid samples were collected aseptically on days 1 (before joint lavage), 2, 3, 4, and 8 for complete cytological analysis. Lameness, joint swelling, and pain were recorded daily. Calves were euthanized on day 8 for gross and histological analyses of synovial membranes and articular cartilage. Synovitis was evaluated using a scoring system reflecting inflammatory changes in synovial membranes.Joints irrigated with HSS were more distended and painful compared with isotonic control joints. Swelling decreased consistently in the joints lavaged with 7.2% HSS, whereas it remained unchanged in joints lavaged with 15% HSS. Slight to moderate lameness was observed in the joints lavaged with 15% HSS. In comparison to isotonic saline joints, total protein concentration was significantly increased on day 2 and 3 for the joints lavaged with 7.2% HSS (P ≤ 0.01) and on days 2, 3, and 4 in the joints lavaged with 15% HSS (P ≤ 0.0006). Gross and histological findings revealed that synovitis was more severe in the joints lavaged with 15% HSS but variable in the joints lavaged with 7.2% HSS. No significant differences were observed for the articular cartilage.Fifteen percent HSS is not recommended for joint lavage. Although irrigation with 7.2% HSS may induce a variable synovitis, it was found appropriate for joint lavage. Its effects on septic joints remain undetermined.

Bronchoalveolar lavage and pulmonary histopathology in harp seals (Phoca groenlandica) experimentally infected with Otostrongylus circumlitus.

The objective of this study was to characterize pathologic changes associated with experimental infection of harp seals (Phoca groenlandica) with the lungworm Otostrongylus circumlitus (Metastrongyloidea: Crenosomatidae). The leukocyte differential cell count in samples obtained by unguided bronchoalveolar lavage (BAL) and the intensity of the histologic lesions in the lungs were assessed in seven harp seals experimentally exposed to 300 infective, third-stage O. circumlitus larvae. Seven unexposed harp seals were used as controls. First-stage larvae were observed in the feces of three of the seven exposed seals at 38, 42, and 45 days postexposure (dpe). Adult nematodes were found in the right primary bronchi of two of these three seals at necropsy 53 dpe. Fifty-six BALs were performed on the 14 seals. No statistical difference was observed between the exposed and control seals and among the four sampling times in percentage of neutrophils and macrophages in the BAL fluid. A significant difference was observed between the exposed and control seal groups in the percentage of eosinophils (P<0.0001), the count of eosinophils having increased by a factor of 70.4 in exposed seals. Significant statistical differences were observed between exposed and control seals in intensity of interstitial inflammation (P=0.001), bronchitis (P=0.02), bronchiolitis (P=0.04), alveolitis (P=0.03), and interstitial granulomatous inflammation (P=0.04). Our findings showed that harp seals are susceptible to infection with O. circumlitus. However, parasitic infections were transient and of low intensity, at least under our experimental conditions.

Optimization of in vitro transcription and full-length cDNA synthesis using the T4 bacteriophage gene 32 protein.

We evaluated the effect of the T4 bacteriophage gene 32 protein (T4gp32) on in vitro transcription and reverse transcription. T4gp32 doubled the yield of in vitro transcripts obtained with T7 RNA polymerase and increased the yield of cDNA synthesis when used in combination with an RNaseH-deficient Moloney murine leukemia virus [Au: ok] reverse transcriptase. The positive effect could be correlated with the RNA chaperone activity of T4gp32. T4gp32 stimulated the synthesis of long cDNAs, particularly species longer than 7 kb. By comparison, thermal activation of reverse transcriptase with trehalose only boosted the production of shorter cDNAs. For the construction of an Arabidopsis thaliana cDNA library, where the average cDNA size is 1.2 kbp, both the presence of T4gp32 under standard reaction conditions as well as thermal activation resulted in similarly high percentages of full-length cDNA. However, the inclusion of T4gp32 in a standard reverse transcription reaction resulted in the highest cDNA yield. We conclude that the addition of T4gp32 in standard reverse transcription reactions can increase the quality and yield of full-length cDNA libraries.