Quantitative risk assessment of noroviruses in drinking water based on qualitative data in Japan

Noroviruses are one of the major causes of viral gastroenteritis in Japan. A quantitative risk assessment was conducted to evaluate the health risk caused by this virus in drinking water. A Monte Carlo analysis was used to calculate both the probability of infection and the disease burden using disability-adjusted life years (DALYs). The concentration of noroviruses in tap water was estimated based on qualitative data and a most probable number (MPN) method with an assumed Poisson lognormal distribution. This numerical method was evaluated using two sets of available count data of Cryptosporidium: that collected from a river and that found in tap water in Japan. The dose-response relationships for noroviruses were estimated using assumed ID50 (10 or 100). The annual risk was higher than the US-EPA acceptable level (10(-4) [infection/ person-year]) but around the WHO level (10(-6) [DALYs/ person-year]). As suggested by others, since microbial concentrations are generally lognormally distributed, the arithmetic mean was directly related to the annual risk, suggesting that the arithmetic mean is more useful in representing the degree of microbial contamination than the geometric mean.     

Sub-critical water treatment of rice bran to produce valuable materials

The target of this study is application of sub-critical water as a green solvent for hydrolysis of rice bran and extraction of its oil in order to obtain value-added materials. Experiments were carried out at temperatures ranging from 100 to 360 °C with 5 min residence time in a batch reactor. Four phases were isolated after reaction: hexane-soluble, acetone-soluble, water-soluble, and solid residue phases. Rice bran oil was successfully and efficiently obtained by sub-critical water extraction. Significant increases of total organic carbon (TOC) and total nitrogen (TN) in the water phase were also observed, because polysaccharides and proteins (generally bio-macro polymers) in rice bran were hydrolysed by sub-critical water. The highest yields of TOC and TN were 140 and 13 mg/g dry matter, respectively. As a result, varieties of compounds, such as amino acids, organic acids, and water-soluble saccharides, were identified in the water phase. In particular, significant amounts of water-soluble sugars (maximum yield of total sugars was nearly 190 mg/g dry matter) proved that sub-critical water was a promising medium for dissolution of biomass in water. Acetone-soluble contents were attributed to tar, carbonized biomass, and in general, water- and hexane-insoluble compounds. Solid residue consisted of mainly un-reacted rice bran and insoluble inorganic compounds.     

Pharmacological studies on basic ethers (R111 and R97) with antispasmodic activity

Pharmacological properties and acute toxicity of 2-tolyl 1-phenyl-3-(2-methylpiperidino) propyl ether methyl bromide (R111) and 2-chlorophenyl 1-phenyl-3-(2-methylpiperidino) propyl ether methyl iodide (R97) were examined. The results obtained were as follows: (1) In the analgesic effects, RIII and R97 inhibited markedly the acetic acid-induced writhing in mice, but in reducing pain induced by heat, R111 and R97 showed negative results. The local anesthetic effect of R111 was approximately equal to that of procaine. R111 and R97 showed no effects on spontaneous locomotion, the convulsion induced by strychnine or pentetrazol, and normal body temperature. (2) R111 and R97 antagonized acetylcholine, barium chloride, nicotine and serotonine-induced spasm, but not that of histamine and bradykinin. In particular they possessed marked anti-barium chloride activity, where their effects were 20 to 30 times more active than that of papaverine. (3) R111 and R97 indicated weak mydriatic activity. (4) R111 and R97 showed inhibitory effects on the pilocarpine-induced sialic secretion and the propulsive movements of the small intestine, but their inhibitory effects on the gastric secretion were relatively weak. (5) R111 and R97 displayed protective effects in Shay's ulcer, but had no curative effects on acetic acid ulcer. (6) R111 and R97 induced temporary reduction of arterial blood pressure and blood flow immediately after the administration of the test compounds in anesthetized rabbits. However, these agents induced no change in ECG, heart rate and respiration. (7) Intraperitoneally administered R111 and R97 were effective in inhibiting the carrageenin-induced edema in the hind paw of rats. From the above results, it may be considered that R111 and R97 have together strong cholinergic blocking and muscotropic antispasmodic effects, moreover, no significant effects on the central nervous system.     

Flaujeac factor deficiency. Reconstitution with highly purified bovine high molecular weight-kininogen and delineation of a new permeability-enhancing peptide released by plasma kallikrein from bovine high molecular weight-kininogen

Flaujeac trait is the functional deficiency of a plasma protein of the intrinsic coagulation, kinin-forming, and plasma fibrinolytic pathways. The Flaujeac factor in man has been isolated and tentatively identified as a kininogen of high molecular weight (HMW). Highly purified bovine HMW-kininogen, but not bovine low molecular weight kininogen, repaired Flaujeac factor deficiency. The two subspecies of this molecule, HMW-kininogen a and HMW-kininogen b, also corrected Flaujeac factor deficiency. When bovine HMW-kininogen was incubated with bovine plasma kallikrein, kinin-free HMW-kininogen, bradykinin, and a glycopeptide fragment (peptide 1-2; 12,584 daltons) were rapidly released. None of these fragmentation products corrected Flaujeac factor deficiency alone or in mixtures. The function of HMW-kininogen appeared to depend upon the structural integrity of the native molecule. When injected in concentrations of 2 pmol-8 nmol/0.1 ml, peptide 1-2 caused increased vascular permeability in rabbits, rats, or guinea pigs. The enhanced permeability was maximal within 1-2 min and terminated in 5-10 min, differing from that of bradykinin or histamine. Injected together in equimolar amounts, peptide 1-2 and bradykinin produced a synergistic permeability response which was immediate in onset as well as prolonged in duration. Peptide 1-2 is a rapidly acting, highly basic glyco-peptide which mediates increased vascular permeability in a complementary and synergistic manner with bradykinin.     

Isolation of the YAP1 homologue of Candida utilis and its use as an efficient selection marker

The industrially important yeast Candida utilis is widely used in the production of food and medical materials, but its practical host-vector system has not been well developed. In order to construct a food-grade host-vector system, we isolated the YAP1 homologue, CuYAP1, of C. utilis IAM4264 and evaluated its use as a selection marker in transformation. A DNA probe was obtained by PCR using degenerate primers and the CuYAP1-encoding 438 amino acid protein was isolated by hybridization. Although the amino acid identity of Yap1 and CuYap1 was 28.7% as a whole, the characteristic bZip region and two cysteine-rich domains (CRDs) showed a higher homology. CuYAP1 was inserted in a CuGAP1 expression cassette of the C. utilis ARS vector pRI177, and C. utilis AHU3053 was transformed with this plasmid. A number of transformant colonies grew in the presence of cycloheximide, which indicated that CuGAP1-CuYAP1 is an effective selection marker. The transformant also showed higher resistance to other agents, including cadmium and fluconazole. The overexpression of CuYAP1 in S. cerevisiae also resulted in increased resistance to various types of drugs.     

Determination of γ-glutamyl-valyl-glycine in raw scallop and processed scallop products using high pressure liquid chromatography–tandem mass spectrometry

The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography–tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff.     

CoCl(2) inhibits neural differentiation of retinoic acid-treated embryoid bodies

The effects of CoCl(2) on retinoic acid (RA)-treated embryoid bodies (EBs) were investigated. Four-day EBs were treated with 5x10(-6) M of RA for 4 d, then subjected to attached culturing for 7 d in the presence of CoCl(2) at 0, 20, and 100 microM. Differentiation into MAP2- and GFAP-immunopositive cells was inhibited by CoCl(2) in a dose-dependent manner. Next, RA-treated EBs were dissociated into single cells and cultured for 7 d at an initial cell density of 1x10(3)/cm(2). The number of cells increased in a CoCl(2)-dose dependent fashion. In cultures with 100 microM of CoCl(2), more than 90% of the cells were immunopositive for nestin and nestin-immunopositive cells formed clusters, while there were few cells immunopositive for MAP2 or GFAP. These results suggest that CoCl(2) inhibits neural differentiation of RA-treated EB cells and promotes the proliferation of nestin-immunopositive cells, i.e., embryonic stem (ES)-derived neural stem-like cells.     

Development of an Enzyme-Linked Immunosorbent Assay for Specific Detection of Mulberroside A in Mulberry (Morus alba L.) Using Anti-mulberroside A Polyclonal Antibody

An enzyme-linked immunosorbent assay (ELISA) was developed using polyclonal antibody (PAb) against mulberroside A (MuA), a major active component found in the root bark of mulberry (Morus alba L.). MuA was conjugated with the carrier protein bovine serum albumin for immunization to rabbits. The results showed that the antibodies were specific only for MuA and have very low specificity for its aglycone, oxyresveratrol. The ELISA assay was suitable for quantitating MuA in the range of 0.17–15.62 μg/mL with a relative standard deviation (RSD) of less than 5 % for both intra- and inter-assay precision levels. The recovery rates of MuA in the samples were in the range of 97.6–101.4 % with a RSD of less than 5 %. The developed ELISA exhibited a good correlation value (R ²?=?0.994) with the standard high-performance liquid chromatography method in the crude extracts of plant samples. These results suggest that the developed ELISA method using PAb against MuA can be applied to determine MuA content with high specificity, rapidity, and simplicity in mulberry samples. The developed ELISA method described could prove to be useful as an analytical tool for quality control of mulberry and their products.