Different contributions of side-chains in β-d-(1 → 3,6)-galactans on intestinal Peyer’s patch-immunomodulation by polysaccharides from Astragalus mongholics Bunge

Thirteen polysaccharides isolated from an extract of the aerial portions of Astragalus mongholics Bunge demonstrated immunomodulating activity against Peyer’s patch immunocompetent cells. Nine of the active polysaccharide fractions were composed of either arabinogalactans, pectic arabinogalactans or pectins. The activities of the arabinogalactans and pectic arabinogalactans were associated with β-d-(1 → 3)-galactan moieties branched with β-d-(1 → 6)-galactooligosaccharide side-chains having degrees of polymerization of 8 or less. Degradation of the β-d-(1 → 3)-galactan or β-d-(1 → 6)-galactosyl side-chains in the arabinogalactans significantly decreased immunomodulating activity. Rhamnogalacturonan I (RG-I) with β-d-(1 → 3,6)-galactosyl side-chains having terminal β-d-GlcA showed activity in the pectin-enriched fractions. Interestingly, the terminal GlcA was not required for activity of the arabinogalactan-enriched fractions, suggesting at least two different immunomodulating structures.     

Blood kinetics of four intraperitoneally administered therapeutic candidate bacteriophages in healthy and neutropenic mice

Due to multiple-drug resistant bacteria, phage therapy is being revisited. Although most animal experiments focus on therapeutic efficacy, the blood clearance kinetics of phages have not been well described. For further development of an efficient therapeutic strategy, information on phage blood kinetics is important. In this study, time-course concentration changes in peripheral blood of healthy and neutropenic mice were measured using four therapeutic phages (φMR11, KPP10, φEF24C, and KEP10). The results showed a two- to three-day rapid phage clearance, which fits a two-compartment model.     

Functional rescue of temperature-sensitive defects in the cell-cycle mutants of rat 3Y1 fibroblasts by the small t-antigen deletion mutant of simian virus 40

We examined the effects of large T antigen of simian virus 40 (SV40) on the proliferation phenotypes of temperature-sensitive (ts) mutants of rat 3Y1 fibroblasts, which cease proliferating in the G1 phase of the cell cycle at a restrictive temperature (39.8 degrees C). Four ts mutants, each representing independent complementation groups, were transformed with the dl-884 mutant of SV40 which lacks the unique coding region for small t antigen. In the case of two ts mutants, their transformed derivatives did not cease proliferation at 39.8 degrees C. In the other two mutants, the transformed cells continued to enter the S phase but the cells became detached from the dishes thereafter, at 39.8 degrees C. The proliferation phenotypes of the dl-884-transformed cells at 39.8 degrees C were quite similar with those of the same mutants transformed with the wild-type SV40. These results indicate that large T antigen alone is sufficient to overcome the inhibition of cellular entry into S phase caused by four different ts defects and determines the proliferation phenotypes of the cells after entering the S phase at a restrictive temperature, and that small t antigen does not alter the cellular phenotypes determined by large T antigen.     

Existence of phosphoenolpyruvate: carbohydrate phosphotransferase systems in Lactobacillus fermentum, an obligate heterofermenter.

The presence or absence of the phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS) in obligately heterofermentative group III lactobacilli including Lactobacillus brevis (3 strains), L. buchneri (2 strains) and L. fermentum (3 strains) was surveyed systematically for a series of sugars utilizable by these organisms. Contrary to common expectation, PTSs were found in two strains of L. fermentum: sucrose-PTS in one strain; sucrose- and mannose-PTSs in the other. All these activities were found to be constitutive.     

Transient increase in the c-fos mRNA level after change of culture condition from serum absence to serum presence and after cycloheximide addition in rat 3Y1 fibroblasts

When 3Y1 cells resting at a saturation density were mitotically stimulated with serum, the c-fos mRNA level markedly increased in a short period of time and then decreased rapidly to an undetectable level. Subsequent serum deprivation followed by serum re-addition or subsequent cycloheximide addition caused a transient re-increase in the c-fos mRNA level. These results can be explained by assuming that the continuous expression of the c-fos gene at a minimum level is necessary for the eventual initiation of S phase, and that the over-expression of the c-fos gene occurs when the control of the gene expression is transiently disturbed by the change of the culture condition.     

A new species of Elassodiscus (Cottoidei: Liparidae) from the North Pacific with an emended diagnosis of the genus

Ichthyological Research - A new snailfish, Elassodiscus nyctereutes, previously confused with Elassodiscus caudatus, is described on the basis of genetic evidence and morphometric and meristic...     

A Novel Molybdenum Protein with a Low Molecular Mass in Rhodobacter sphaeroides f. sp. denitrificans

A novel molybdenum cofactor-containing protein with a low molecularmass of 20 kDa was found in a photodenitrifier, Rhodobactersphaeroides f. sp. denitrificans. The protein was located inthe cytoplasm and was produced constitutively. (Received March 25, 1993; Accepted May 14, 1993)     

Production and characterization of a monoclonal antibody specific for Salmonella O5-antigen

The present report described the production and characterization of a monoclonal antibody, TMY1, specific for an O-antigen of Salmonella bacilli. The following results were obtained: The slide agglutination test against strains of Salmonella serovars indicated the responsiveness of TMY1. TMY1 was reactive only to strains that also possessed O5-antigen in group O4. The agglutinating ability of TMY1 was absorbed completely with bacilli possessing O5-antigen in group O4. When treated with 1 N HCl, bacilli possessing O5-antigen in group O4 showed no agglutinability in the presence of TMY1. The data indicates that TMY1 was specific for O5-antigen. Strains of Salmonella group O4 were classified by the agglutination test with TMY1 into two subgroups, O5-antigen positive and negative, suggesting the usefulness of TMY1 as an epidemiologic tool for the serotyping of Salmonella.