Water soluble proteins (WSP) in broad beans, Vicia faba, were purified, and their scavenging effects on free radicals and active oxygen species were investigated. The purification steps included ammonium sulfate precipitation followed by sequential chromatography on Sephadex G-75. The final gel filtration step yielded two peaks of scavenging activity, each containing M(r) values of 70 kDa (peak I) and 28 kDa (peak II). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of peak II fraction gave a single band with M(r) of 14 kDa, indicating that peak II protein is dimeric. WSP exhibited a marked scavenging effect on superoxide, and also an effect on hydrogen peroxide, but not so much on 1,1-diphenyl-2-picrylhydrazyl radical. WSP had only a small amount of sulfhydryl groups. Thus, the sulfhydryl groups are not responsible for the scavenging activity of WSP.

No abstract

No abstract

No abstract

ABSTRACT. We examined nasal swab and lung homogenate samples collected from pigs experimentally and naturally infected with Mycoplasma hyopneumoniae for the detection of M. hyopneumoniae by the nested PCR (nPCR) and culture methods. In the 23 experimentally infected pigs, M. hyopneumoniae was commonly detected in nasal swabs by the nPCR and culture methods at 4 weeks after inoculation, and there was a significant correlation (P<0.01) between the titers of viable organisms in nasal swabs and in lung homogenates in the experimentally inoculated pigs. In the naturally infected pigs, on the other hand, discrepancies in detection were found between nasal swab and lung homogenate samples in 17 of 36 cases, although the presence of gross lung lesions correlated relatively well with the detection of organisms from the samples. Our results indicated that the diagnosis of mycoplasmal pneumonia by nPCR in individual pigs with nasal swabs is reliable under these experimental conditions. At present, nPCR with nasal swabs should only be used for monitoring the disease status at the herd level under field conditions.

No abstract

No abstract

ABSTRACT. Replication of porcine reproductive and respiratory syndrome (PRRS) virus in swine alveolar macrophages (AM) and cell population in broncho-alveolar lavage fluid (BALF) obtained from PRRS virus-infected pigs were investigated. BALF samples were periodically collected from 6 pigs infected with PRRS virus and 3 non-inoculated control pigs by means of fiber-optic bronchoscope between post-inoculation day (PID) 0 and 56. The mean ratio of macrophages in BALF collected from infected group was 92.7 ± 3.2% before inoculation and gradually decreased from PID 14. On the other hand, the ratio of lymphocytes was 4.8 ± 3.2% before inoculation and increased from PID 21 and indicated 41.8 ± 9.1% on PID 28. After that, they decreased gradually and that of macrophages correspondingly increased. The ratio of neutrophils maintained between 0.7% and 5.1%. The ratios of macrophages, lymphocytes and neutrophils collected from control group were almost stable through the examination. Intracellular PRRS virus antigens in AM were detected from PID 2 by indirect immunofluorescence assay (IIFA). PRRS virus was first isolated from BALF samples collected from inoculated group between PID 2 and 49. From serum, virus was isolated between PID 2 and 21. Antibodies in sera measured by IIFA to PRRS virus were first detected on PID 14 and the antibody titer rose to 1:640 or 1: 1,280. The results suggested that PRRS virus replicates in swine AM for a relatively long period. -KEY WORDS: alveolar macrophage, broncho-alveolar lavage, PRRS virus, swine.