Search

Streptococcus parauberis is a known etiologic agent that causes damage leading to death in flatfish (paralichthys olivaceus). Liposomes were used to deliver streptococcal oral vaccines to the intestinal mucous membranes of paralichthys olivaceus. The liposomes were coated for stabilization, and stability was measured with high performance liquid chromatography (HPLC). The liposomes were stable until day nine and were orally administered to flatfish as a vaccine. The resultant antibody titers were analyzed. The titers resulting from the uncoated liposomes were highest two weeks after the oral administration, and those resulting from the coated liposomes were highest one week after boosting. In addition, the bacteria were subcutaneously injected to artificially infect flatfish and the survival rates and relative survival rates were analyzed. The coated liposomes were found to yield the highest survival rate.

Bisphenol A (BPA), generally known as bisphenols, has been identified as a potential estrogenic substance. BPA must be conjugated to carrier protein and BSA was commonly used. 4,4-Bis(4-hydroxyphenyl) valeric acid (BHPVA) has a bisphenolic structure and a long carbon chain with a reactive carboxyl group on the end. In this study, BHPVA-BSA was used to produce polyclonal antibody against bisphenolic structure, and a modified competitive ELISA method for quantification of BPA was developed. This system was based on BHPVA-BSA for polyclonal antibody production against bisphenolic structure, and BHPVA-HRP for determination of BPA substituting detection antibody in competitive reaction. Recovery was assessed at 10 different concentrations (2-1000 ng/ml) of BHPVA, and the recovery range was from 96.3% to 107.2%. The variation was from 6.2% to 9.8% for intra assay and from 10.1% to 12.6% for inter assay. The quadratic was used to establish the curve regression. The range was found to be between 2 and 1000 ng/ml. This modified competitive ELISA method has proven to be a very useful tool for quantification of BPA without the unexpected interaction of BSA and anti-BSA polyclonal antibody.

A sandwich enzyme-linked immunosorbant assay (ELISA) was developed to quantitatively detect Bullfrog (Rana catesbeiana) vitellogenin (VTG) levels. This procedure involved a sandwich ELISA using monoclonal antibodies of BVmA1 and BVmA2 against Bullfrog-VTG, and BVmA1 conjugated to horseradish peroxidase as the detection antibody. The assay range was between 9.4 ng/ml and 1200 ng/ml and the recovery of the VTG added to Bullfrog control male serum was 92.0-108.8%. Male Bullfrog was induced by injection 17beta-estradiol (E2) for four weeks and Bullfrog-VTG levels were measured each week. Histological analysis was performed for investigating the correlation of the effect to male reproduction and Bullfrog-VTG level variation depending on E2 dose. After two weeks of E2 exposure, the induced Bullfrog-VTG level was significantly higher than Bullfrog control female (p0.05). After four weeks of E2 exposure, the rupture and fusion of seminiferous tubule in the testes of male Bullfrog were shown and provided direct evidence that the reproduction of male Bullfrog was affected by estrogenic compounds. Bullfrog-VTG bioassay, using the sandwich ELISA, could be a sensitive and useful tool for quantification of estrogenic principles in aquatic environments.

In this study, the effects of the ursodeoxycholic acid (UDCA), and its derivatives, on DNA replication were examined using simian virus (SV40) DNA replication in vitro. We found that UDCA and its derivatives inhibited SV40 DNA replication, and predominantly inhibited the initiation stage of DNA replication. UDCA and its derivatives inhibited the DNA cleavage by topoisomerase I (topo I). Among them, HS-1183 significantly reduced the activity of topo I. UDCA, at 100 microM, significantly reduced polymerase alpha-primase (pol alpha-primase) activity, but HS-1030 and HS-1183 showed a weak inhibitory effect. The ssDNA binding activity of replication protein A (RPA) was little affected by UDCA and HS-1030, but was weakly inhibited by HS-1183. Based on their properties, we suggest that UDCA and its derivatives might inhibit some molecules that is required to establish replication forks during the initiation reaction and their cytotoxicity might be related to the inhibitory effect they have on this fundamental cellular process.