Detection of specific antibodies against deflagellated Salmonella Enteritidis and S. Enteritidis FliC-specific 9kDa polypeptide

Specific antibody levels of laying hens and young chickens experimentally infected with Salmonella Enteritidis and vaccinated farm flocks were evaluated by enzyme-linked immunosorbent assays (ELISAs) with two different antigens, deflagellated S. Enteritidis whole cell (DEWC) and S. Enteritidis FliC-specific 9kDa polypeptide (SEP9). Infected laying hens excreted S. Enteritidis throughout the experimental period, and the specific antibody titers in DEWC-ELISA, were significantly higher than the uninfected group. It suggests that this DEWC-specific antibody will serve as an effective indicator of S. Enteritidis infection, especially for non-vaccinated laying flocks. SEP9-specific antibodies were detected in spray-inoculated young chickens but not in oral-inoculated young chickens. Compared with greatly high SEP9-specific antibody levels of vaccinated farm flocks, no response was observed in orally infected hens. These results indicate that S. Enteritidis discontinues expressing SEP9 once it has crossed the intestinal barrier, and that SEP9-ELISA will serve as a valuable monitoring tool for the status of S. Enteritidis vaccination on a flockwide basis, independent of stable S. Enteritidis infections.     

Alcohol and dietary fibre intakes affect circulating sex hormones among premenopausal women

BACKGROUND: The association of alcohol and fibre intake with breast cancer may be mediated by circulating sex hormone levels, which are predictors of breast cancer risk. OBJECTIVE: To evaluate the relationship of alcohol and dietary fibre intake with circulating sex hormone levels among premenopausal women. METHODS: A total of 205 premenopausal women completed a validated food-frequency questionnaire at baseline and after 2 years; blood samples taken at the same time were analysed for circulating sex hormone concentrations, including oestrone (E1), oestradiol (E2), free E2, progesterone, androstenedione and sex hormone-binding globulin, by radioimmunoassay. We used mixed models to estimate least-square means of sex hormone concentrations for alcohol intake categories and quartiles of dietary intake. RESULTS: After adjustment for covariates, alcohol consumption was moderately associated with higher circulating oestrogen levels; those who consumed more than one drink per day had 20% higher E2 (Ptrend=0.07) levels than non-drinkers. In contrast, higher dietary fibre intake was associated with lower serum levels of androstenedione (-8% between the lowest and highest quartiles of intake, Ptrend=0.06), but not oestrogens. Similarly, consumption of fruits (-12%, Ptrend=0.03), vegetables (-9%, Ptrend=0.15) and whole grains (-7%, Ptrend=0.07) showed inverse associations with androstenedione levels. CONCLUSIONS: The consistency of the observed differences in sex hormone levels associated with alcohol and fibre-rich foods indicates that these nutritional factors may affect sex hormone concentrations and play a role in breast cancer aetiology and prevention.     

The specific antibody to Brachyspira aalborgi in serum obtained from a patient with intestinal spirochetosis

Serum obtained from a patient histopathologically diagnosed as intestinal spirochetosis was investigated serodiagnostically by agglutination test. B. aalborgi which is a human intestinal spirochete reacted strongly with the human serum, while B. pilosicoli which has potential pathogenicity to humans reacted with the serum, but as strongly and its titer was different than the other three species. On the other hand, intestinal spirochetes (Matsumoto isolates) were isolated from the biopsy samples of the patient. The morphological, biochemical, and genetic characteristics of the isolates were very similar to those of B. aalborgi. Furthermore, the protein profiles of the Matsumoto isolates were also similar to those of B. aalborgi but were different than those of B. pilosicoli and B. hyodysenteriae. The reaction profiles of the Matsumoto isolates in immunoblotting were relatively similar to those of B. aalborgi except for a 74 kDa band but were different from those of B. pilosicoli and B. hyodysenteriae. Therefore, we identified the Matsumoto isolates as B. aalborgi and diagnosed the patient with a B. aalborgi infection.     

Probenecid: its chromatographic determination, plasma protein binding, and in vivo pharmacokinetics in dogs

Pharmacokinetics (PK) of probenecid including plasma probenecid concentrations, in vitro plasma protein binding properties, and in vivo PK parameters were determined in dogs. Probenecid concentrations were best determined by HPLC, which showed good linearity and good recovery with simple plasma preparation. The quantification limit of probenecid was approximately 50 ng/ml at S/N ratio = 3, by simple procedure with HCl and methanol treatment. Probenecid showed two types of binding characteristics, i.e., high-affinity with low-capacity and low-affinity with high-capacity binding. This result indicated 80-88% of probenecid was bound to plasma protein(s) at observed concentrations (< 80 microg/ml) in vivo at an intravenous dose of 20 mg/kg. Plasma probenecid concentration-time profile following i.v. administration in dogs showed biphasic decline and well fitted a two-compartment open model. The total body clearance was 0.34 +/- 0.04 ml/min/kg, volume of distribution at steady-state was 0.46 +/- 0.07 l/kg, elimination half-life was 18 +/- 6 hr, and mean residence time (MRT) was 23 +/- 6 hr. Since probenecid has been known as a potent inhibitor of renal tubular excretion of acidic drugs and highly binds to plasma proteins, our observation in relation to plasma protein binding and PK parameters will serve as the basic information concerning drug-drug interactions in dogs and in other mammalian species.     

Spatiotemporal distribution of Flavobacterium psychrophilum and ayu Plecoglossus altivelis in rivers revealed by environmental DNA analysis

Outbreaks of bacterial cold-water disease (BCWD), caused by Flavobacterium psychrophilum, are widespread in Japan, especially among ayu Plecoglossus altivelis. There are few investigations of F. psychrophilum in river water, and its seasonal distribution has not been clarified. We aimed to identify the spatiotemporal dynamics of F. psychrophilum and ayu to provide information that is useful for establishing a countermeasure for BCWD. Quantitative analysis of environmental DNA (eDNA) was used to clarify the year-round dynamics of ayu and F. psychrophilum. We sampled river water from the Nagara and Ibi rivers in Japan, and conducted monthly water sampling and eDNA quantification. Changes in the eDNA concentration of ayu were consistent with the known life histories of the fish. There was a strong negative correlation between the eDNA concentration of F. psychrophilum and water temperature, suggesting a strong dependence of F. psychrophilum dynamics in the river on water temperature. Furthermore, relatively high eDNA concentrations were recorded for both organisms in early summer and fall, suggesting that ayu is infected with F. psychrophilum during these seasons when experiencing up- and downmigration, respectively.

     

The reduced height genes do not affect the root penetration ability in wheat

Root penetration (RP) ability into compacted soil is an important breeding target for drought avoidance by durum (Triticum turgidum L. var. durum) and bread wheat (T. aestivum L.) in regions with compacted soils and water deficits. However, it is said generally that yield of the current cultivars introduced the reduced height gene (Rht-B1b or Rht-D1b) are more sensitive to drought stress than that of old landraces. This study investigated the effect of the Rht genes on RP ability using the seedlings of near-isogenic lines (NILs) of Rht genes of LD222 durum wheat and April Bearded bread wheat, and 110 recombinant inbred lines (RILs) of durum wheat derived from the cross between the tall landrace (Jennah Khetifa; Rht-B1a Rht-B1a) and semi-dwarf cultivar (Cham1; Rht-B1b Rht-B1b). One seedling of each genotype was grown in a pot (6 cm diameter, 15 cm height) with a disc of 3 mm thickness made from paraffin and Vaseline mixture (PV) in 10 cm depth, as a substitute for a compacted soil layer. The RP index [number of roots penetrating through the PV disc per plant (PVRN)/total number of seminal and crown roots per plant (TRN)] was measured at eight weeks after sowing and used as the indicator of RP ability of seedling. In NILs, the shoot length decreased significantly because of the introduction of either Rht-B1b or Rht-D1b dwarfing genes, but the RP index was similar to those of tall parents. In RILs, although the RP index and shoot length were higher in Jennah Khetifa than in Cham1, the relationship between RP index and shoot length was not significant (r = 0.156). Both results indicate that RP ability of wheat does not link to dwarfness regulated by Rht genes. We suppose therefore that it would be possible to develop a high yielding semi-dwarf cultivar with excellent RP ability.     

Behavior of monolignol glucosides in angiosperms

To examine the behavior of cinnamaldehyde and cinnamyl alcohol glucosides in lignifying tissues, angiosperms were subjected to tracer experiments using radioisotope-labeled and stable isotope-labeled glucosides. The aglycone from coniferaldehyde glucoside was efficiently incorporated into guaiacyl and syringyl lignin as a cinnamyl alcohol unit. The aglycone from coniferin was also incorporated into guaiacyl and syringyl lignin. However, some of the coniferin-derived aglycone that was incorporated into lignin passed through a cinnamaldehyde form prior to dehydrogenative polymerization. When coniferin was administered together with coniferaldehyde glucoside, syringyl units were rarely synthesized from coniferin via the cinnamyl alcohol stage, whereas numerous syringyl units were synthesized from coniferaldehyde glucoside. These observations suggest that the coniferaldehyde form is crucial for the biosynthesis of syringyl lignin in angiosperms.