Detection of antibodies against porcine parvovirus in swine sera by enzyme-linked immunosorbent assay

An enzyme-linked immunosorbent assay (ELISA) was developed for detection of antibody against porcine parvovirus in swine sera. The antigen used for the assay was partially-purified virus treated with fluorocarbon and shown to contain 7 proteins by sodium dodecylsulfate-polyacrylamide gel electrophoresis. Of these proteins 83-, 64- and 60-K proteins reacted in Western immunoblotting with swine serum after infection with porcine parvovirus. Antibody responses were demonstrated by ELISA in pigs subcutaneously-infected with porcine parvovirus as by hemagglutination-inhibition (HI) test and Western immunoblotting reaction with the 83-, 64- and 60-K viral proteins. The results of ELISA on random swine-serum samples were well-correlated with those of the HI test. These findings indicate the usefulness of the ELISA as a serological tool for porcine parvovirus infection.     

Modification of three avian viruses passaged in Chinese hamster lung cells (Don) in pathogenicity to chicken embryo

The Beaudette 42 strain of avian infectious bronchitis virus, Sato strain of Newcastle disease virus, and Uchida strain of avian reovirus were passaged in Chinese hamster lung cells (Don), and some properties were examined. The Don-passaged strains showed a difference in replication in Don and chicken embryo kidney cells in one-step growth curve examinations and a partial modification in pathogenicity to chicken embryos; nevertheless, neutralization tests revealed no serological alteration.     

Pharmacokinetics of cycloalliin, an organosulfur compound found in garlic and onion, in rats

Cycloalliin, an organosulfur compound found in garlic and onion, has been reported to exert several biological activities and also to remain stable during storage and processing. In this study, we investigated the pharmacokinetics of cycloalliin in rats after intravenous or oral administration. Cycloalliin and its metabolite, (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid, in plasma, urine, feces, and organs was determined by a validated liquid chromatography-mass spectrometry method. When administered intravenously at 50 mg/kg, cycloalliin was rapidly eliminated from blood and excreted into urine, and its total recovery in urine was 97.8% +/- 1.3% in 48 h. After oral administration, cycloalliin appeared rapidly in plasma, with a tmax of 0.47 +/- 0.03 h at 25 mg/kg and 0.67 +/- 0.14 h at 50 mg/kg. Orally administered cycloalliin was distributed in heart, lung, liver, spleen, and especially kidney. The Cmax and AUC0-inf values of cycloalliin at 50 mg/kg were approximately 5 times those at 25 mg/kg. When administered orally at 50 mg/kg, cycloalliin was excreted into urine (17.6% +/- 4.2%) but not feces. However, the total fecal excretion of (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid was 67.3% +/- 5.9% (value corrected for cycloalliin equivalents). In addition, no (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid was detected in plasma (<0.1 microg/mL), and negligible amounts (1.0% +/- 0.3%) were excreted into urine. In in vitro experiments, cycloalliin was reduced to (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid during anaerobic incubation with cecal contents of rats. These data indicated that the low bioavailability (3.73% and 9.65% at 25 and 50 mg/kg, respectively) of cycloalliin was due mainly to reduction to (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid by the intestinal flora and also poor absorption in the upper gastrointestinal tract. These findings are helpful for understanding the biological effects of cycloalliin.     

Comparative studies of some phenolic compounds (quercetin, rutin, and ferulic acid) affecting hepatic fatty acid synthesis in mice

The physiological activities of some phenolic compounds affecting hepatic fatty acid synthesis in mice were compared. Male ICR mice were fed an experimental diet containing 1% quercetin dihydrate, rutin, or ferulic acid or a control diet free of phenolic compounds for 15 days. Quercetin significantly lowered serum cholesterol and phospholipid levels in mice. Also, the serum triacylglycerol level was considerably lower in mice fed the quercetin-containing diet than in those fed a diet free of phenolic compounds, although the difference was not significant. Rutin and ferulic acid did not affect these parameters. Quercetin significantly reduced the activity and mRNA levels of various enzymes involved in hepatic fatty acid synthesis. Rutin reduced a few of the parameters for lipogenesis, but ferulic acid did not affect any of the parameters. It was suggested that a reduction in hepatic lipogenesis is the mechanism underlying the hypolipidemic effect of quercetin.     

Effect of Mechanical Stretching on Expressions of Muscle Specific Transcription Factors MyoD, Myf-5, Myogenin and MRF4 in Proliferated Myoblasts

We examined expression of four important members of myogenic regulatory factors (MRFs) in the myoblasts both at mRNA and protein levels, which were subjected to mechanical stretching in in vitro condition. Our results showed that MyoD expression existed both in the stretch and in the control group at all time periods of the mechanical stimulus. Myf-5 expressed only at early stage of the stretch group. Although mRNA and protein expressions of myogenin and MRF4 were detected both in the stretch and in the control group at 12 h after the stretching, their expressions were only shown in the stretch group at 24 h after the mechanical stimulus. However, at 36 and 48 h, none of the MRFs examined except MyoD appeared in both groups. Our results suggest that the MRFs are up-regulated upon mechanical stimulus and each member plays a different major role for either proliferation or differentiation of the myoblasts.     

Emergence and frequency of highly benzimidazole-resistant Colletotrichum gloeosporioides, pathogen of Japanese pear anthracnose, after discontinued use of benzimidazole

From July to October 1999, two Japanese pear varieties, Housui and Niitaka, were unexpectedly infected with Colletotrichum gloeosporioides causing anthracnose in Saga Prefecture of Japan. More than 90?% of the anthracnose fungus strains collected in 1999 were highly benzimidazole-resistant and distributed at high frequencies across pear-producing areas. The control of anthracnose by benzimidazole fungicides could not be confirmed in orchards where the isolation frequency of resistant strains was high. The frequency of resistant strains did not significantly decline, even 2?C5?years after the last use of benzimidazole fungicides.     

A comparison of gel diffusion, fluorescent antibody and virus isolation methods in experimental and natural cases of infectious bursal disease.

In studies with chicks inoculated with the Sk-1 strain of infectious bursal agent the bursa of Fabricius was found to be the tissue of choice for virus isolation as well as for use in the fluorescent antibody test and the agar gel diffusion test. In separate experiments positive results were obtained until postinoculation days 3 or 4 by the agar gel diffusion test, 5 or 6 by the fluorescent antibody test and 14 by the virus isolation method, respectively. Bursas from chickens involved in seven natural outbreaks of infectious bursal disease were then examined by these three methods. Virus was isolated from six outbreaks and infectious bursal agent antigen was demonstrated in three by the agar gel diffusion test method and seven (three by direct examination and four after one passage in chicks) by the fluorescent antibody test method. Passage in chicks was required when nonspecific fluorescence complicated the interpretation of fluorescent antibody test results.