Effects of Escherichia coli strain Nissle 1917 on immune responses of Japanese quails (Coturnix japonica) to Newcastle disease vaccines.

Abstract. Background: The development of proper immune responses to Newcastle disease (ND) vaccines is important in controlling the disease. Escherichia coli strain Nissle 1917 (EcN) is involved in regulating the immune system. Aims: The current study evaluated the effects of EcN on immune responses to ND live vaccines in Japanese quails. Methods: A total of 150 one-day-old quails were divided into three equal groups. Groups A and B received 107 and 106 CFU/ml/day of EcN, respectively, sprayed on their diets, while group C received 1 ml/day of PBS. All birds were vaccinated with B1 and Lasota vaccines at 10 and 20 days of age, respectively. Serum samples were collected in order to assay the levels of IgA and certain cytokines, including IL4, IFN-α, and IFN-γ, as well as antibody titers to NDV by HI and ELISA methods. Results: No significant difference (P>0.05) was observed in serum IgA and IFN-α levels among the groups. However, concentrations of IFN-γ and IL-4 in 42-day-old chicks in group A were significantly (P<0.05) higher than in both other groups. After 15 days of the second vaccination, the mean HI titer following NDV was significantly higher in group A than group C. Groups B and C showed significantly lower HI titer than group A after 22 days of the second vaccination. Mean ELISA titer to NDV was significantly (P<0.05) higher in group A than in groups B and C after 22 days of the second vaccination. Conclusion: It seems that the spraying of 107 CFU/ml/day of EcN on quail diets enhances the immune response to NDV vaccines by increasing serum levels of IFN-γ and IL-4.

Identification and characterization of probiotic lactic acid bacteria isolated from traditional persian pickled vegetables.

Background: The pickle, a traditional fermented product, is popular among Iranians. Much research has been conducted worldwide on this food group. Due to a lack of related data in Iran, this study was conducted to isolate and identify dominant lactic acid bacteria (LAB) in pickles and salted pickles. Materials and methods: Seventy samples were collected from different regions of Iran. The isolated bacteria were identified as LAB by Gram staining and catalase by using MRS agar. Then, those strains were identified at the species level by physiological tests (e.g., gas production from glucose, arginine hydrolysis, CO2 production from glucose in MRS broth, carbohydrate fermentation) and growth at temperatures of 15°C, 30°C, and 45°C in MRS broth for 3 days. The probiotic characteristics of these bacteria were studied using acid and bile tolerance. The corresponding results were verified using PCR analyses of the 16S rDNA region. Results: 114 presumptive lactic acid bacteria (LAB) with Gram-positive and catalase-negative properties were obtained from the samples. The results revealed that all isolated bacteria were identfied as Lactobacillus (L.) plantarum, L. brevis, L. pentosus, L. casei, L. paracasei and Leuconostoc mesenteroides. The predominant LAB in these pickles was L. plantarum, which was isolated from most of the samples. Among the 114 LAB, 7 isolated species have probiotic potential. Six out of seven were recognized as L. plantarum and one remained unidentifiable by biochemical testing. PCR analysis and sequencing of the 16S rDNA region using 27f and 1522r primers showed that all of the probiotic strains were L. plantarum. Conclusion: The results of this study showed that the dominant LAB in traditional Persian pickled vegetables are L. plantarum, L. brevis, L. pentosus, L. casei, L. paracasei, and Leuconostoc mesenteroides. Moreover, L. plantarum was recognized as a probiotic species in pickled vegetables. The raw data obtained from this study can be used in the pickling industry to improve the nutritional value of products.

Effect of zinc ion on peroxidase activity of serum in cow.

In this study, for clarifying some possible mechanism of zinc toxicity, the effect of increasing amounts of Zn2+ ion on peroxidase activity was investigated in vitro in serum of cow. The H2O2-mediated oxidation of o-dianisidine was used to assess the peroxidase activity. Results show that after preincubation of serum with 0.2-20 mM Zn2+ concentration for 5 min, peroxidase activity was inhibited compared to the control and decreased rapidly with increasing metal concentrations. The enzyme was completely inhibited after 5 min preincubation in 30 mM Zn2+. When the preincubation of serum and Zn2+ was prolonged to 30 and 60 min, the enzymatic activity decreased more rapidly with increasing metal concentration. Extended exposure of the enzyme to lower concentrations of the metal brought about the same effect as shorter exposure to higher metal concentrations.

BIAS: Bioinformatics Integrated Application Software.

MOTIVATION: We introduce a development platform especially tailored to Bioinformatics research and software development. BIAS (Bioinformatics Integrated Application Software) provides the tools necessary for carrying out integrative Bioinformatics research requiring multiple datasets and analysis tools. It follows an object-relational strategy for providing persistent objects, allows third-party tools to be easily incorporated within the system and supports standards and data-exchange protocols common to Bioinformatics. AVAILABILITY: BIAS is an OpenSource project and is freely available to all interested users at http://www.mcb.mcgill.ca/~bias/. This website also contains a paper containing a more detailed description of BIAS and a sample implementation of a Bayesian network approach for the simultaneous prediction of gene regulation events and of mRNA expression from combinations of gene regulation events. CONTACT: hallett@mcb.mcgill.ca.

Expression of interleukin-6 and interleukin-6 receptors in human granulosa lutein cells.

Cytokines are important regulators of reproductive functions. Significant amounts of interleukin-6 (IL-6) have been detected in the serum and ascites of patients with ovarian hyperstimulation syndrome (OHSS). These findings suggest the involvement of IL-6 as a mediator in the pathogenesis of OHSS. This study was performed to analyse IL-6 and IL-6 receptor (IL-6-R) expression in human granulosa lutein cells (GC). GC were cultured after isolation from follicular fluid. IL-6 concentrations in follicular fluid and serum from individual patients and GC supernatants were measured by enzyme-linked immunosorbent assay. We found detectable concentrations of IL-6 in serum and follicular fluid of all patients. Expression of IL-6 in GC was shown immunocytochemically. IL-6 mRNA was detected in GC by in-situ hybridization. Gene expression for IL-6 and IL-6-R in GC was demonstrated using reverse transcription-polymerase chain reaction. IL-6 significantly inhibited human chorionic gonadotrophin (HCG)-induced progesterone secretion of GC. The results of our study suggest that IL-6 is expressed in HGC and that this cytokine is able to modulate GC function via its specific receptor. This is the first report that describes the precence of IL-6-R in human granulosa lutein cells.

Enhancement of uptake of lipopolysaccharide in macrophages by the major outer membrane protein OmpA of gram-negative bacteria.

Monoclonal antibodies (MAb) to lipopolysaccharide (LPS) and to the major outer membrane protein OmpA from Proteus mirabilis were generated and used to monitor the kinetics of uptake in macrophages of LPS as well as LPS bound to OmpA. Uptake was measured by a modified enzyme-linked immunosorbent assay (ELISA) in a microtiter culture system. The MAb were of various immunoglobulin G subclasses and showed strong reactivities with their antigens. Four hybridoma clones recognizing LPS and three recognizing OmpA from P. mirabilis 19 were selected for the present study on the basis of reactions in ELISA and Western blot (immunoblot) analyses. In the uptake assay, it was possible to differentiate between antigen on the cell surface and antigen which had been internalized. Uptake of LPS by macrophages was relatively rapid during the first 4 h of culture and then progressed more slowly over the remaining 24-h observation period. The level of detection of LPS in this assay system was in the nanogram range. When macrophages were pulsed with LPS for 30 min and subsequently washed to remove antigen not bound to the cells, the amount of LPS detectable on the macrophage surface decreased progressively for 3 h after the pulse, which indicated internalization of the antigen. Thereafter, LPS rose to an increased level on the cell surface. The rate of uptake of LPS was more rapid when it was in complex with OmpA. When the fate of OmpA was monitored in the same LPS-protein complexes by use of MAb to OmpA in a pulse experiment, the level of protein measured on the cell surface decreased after an initial rise, which again indicated internalization, but the protein did not reappear on the cell surface in a form detectable with the MAb. Compared with the LPS monitoring system, detection of OmpA associated with macrophages was weak, although the MAb to OmpA reacted strongly with the protein in the ELISA and Western blot analyses.