Nitrocapsanthin and nitrofucoxanthin, respective products of capsanthin and fucoxanthin reaction with peroxynitrite

The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN).     

Identification of putative defense-related genes in Japanese pear against <Emphasis Type="Italic">Alternaria alternata</Emphasis> infection using suppression subtractive hybridization and expression analysis

The Japanese pear pathotype of Alternaria alternata, a toxin-dependent necrotrophic pathogen, causes black spot of Japanese pear by producing the host-specific AK-toxin. Pre-inoculation with nonpathogenic A. alternata or pretreatment with an elicitor prepared from A. alternata reduced disease symptoms caused by the pathogen. Salicylic acid- and jasmonic acid-dependent signaling pathways are not involved in the induced resistance to infection by the pathogen. The expression of multiple defense-related genes in Japanese pear leaves inoculated with nonpathogenic A. alternata was examined using suppression subtractive hybridization. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank database as accessions DC993229–DC993535.     

A dog with myelodysplastic syndrome: chronic myelomonocytic leukemia

An eleven-year-old female pug was referred to Yamaguchi University Animal Hospital for evaluation of anemia and thrombocytopenia. The cytological examination of the peripheral blood showed some giant monocytic lineage blast cells. A few granulocytes and platelets had dysplastic features. On day 7, in addition to increasing the monocytic lineage cells, the dysplastic features of the blood had also increased compared to the initial examination. We performed bone marrow aspiration upon her death. The bone marrow revealed dysplastic features in all three hematopoietic cell lines, and an increase in the monocytic cell line. Based on the features of the bone marrow and the peripheral blood, this case was confirmed to be myelodysplastic syndrome--Chronic myelomonocytic leukaemia (MDS-CMML).     

Transepithelial Transport of Theasinensins through Caco-2 Cell Monolayers and Their Absorption in Sprague-Dawley Rats after Oral Administration

The aim of this study is to illustrate the in vivo and in vitro absorption of theasinensins B and A that are (-)-epigallocatechin-3-O-gallate (EGCG)-(-)-epigallocatechin (EGC) dimer and EGCG dimer, respectively, and their transport pathway across the intestinal membrane. Our animal study by a single oral administration to rats demonstrated the intact absorption of theasinensins into the blood system, which was estimated to be a >10-fold lower absorption amount than EGCG. The in vitro absorption study indicated that theasinensins can be transported across Caco-2 cell monolayers, while their permeability coefficients were also >10-fold lower than those of EGCG and EGC. Transport experiments using cytochalasin D or quercetin as a tight junction (TJ) modulator and a non-saturable permeation revealed that theasinensins were transported across Caco-2 cells in a TJ paracellular diffusion route. In conclusion, the dimers of condensed catechins, theasinensins B and A, can be absorbed intact into rat blood and transported across Caco-2 cell monolayers probably through a TJ paracellular pathway.     

Preliminary study on homing,site fidelity,and diel movement of black rockfish <Emphasis Type="Italic">Sebastes inermis</Emphasis> measured by acoustic telemetry

Several species of fish exhibit strong homing ability and distinct site fidelity to their original habitats and spawning sites. We have studied the homing ability, site fidelity, and diel movement patterns of three nocturnal black rockfish Sebastes inermis. The patterns were studied by radio-linked acoustic positioning system (VRAP) and fixed monitoring receivers (VR2) in Maizuru Bay, Japan from June to July 2004. All tagged fish were displaced by 80–120 m, but they returned to their respective captured sites at dusk, regardless of the time of release. The fish tagged with a depth sensor transmitter displayed active vertical movement just after the release, and subsequently swam near the bottom depth around the captured site. After homing, they displayed small home ranges [average 815 ± 265 m² (SD)] around a single rocky area with one or two core areas (average 64 ± 30 m²). One core area was utilized during the daylight and dark periods, whereas the other was used primarily during the dark period. The depth-tagged fish primarily used the depth of the rock crevice during the daylight, and it spent its dark period between the surface and the deeper bottom depth.     

Effects of olive leaf powder supplemented to fish feed on muscle protein of red sea bream

Olive leaf is known to have the high polyphenol content of 6–9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40 days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle.     

DNA methylation status of bovine blastocyst embryos obtained from various procedures

DNA methylation is an important factor for the regulation of gene expression in early embryos. It is well known that the satellite I sequence is more heavily methylated in bovine somatic cell nuclear transfer (NT-SC) embryos than in embryos derived from in vitro fertilization (IVF). However, the methylation status of bovine embryos obtained by other procedures is not well known. To clarify DNA methylation levels of bovine embryos obtained from various procedures, we examined satellite I sequences in bovine blastocyst (BC) embryos derived from NT-SC, NT using embryonic blastomeres (NT-EM), in vivo (Vivo), IVF and parthenogenetic treatment (PA). Furthermore, in order to evaluate the efficacy of DNA demethylation by the NT procedure, we determined the DNA methylation levels in bovine embryos in which NT was recapitulated (Re-NT). Although the DNA methylation levels in the NT-SC embryos were higher than those in the other embryos, the NT-EM embryos exhibited lower DNA methylation levels. The satellite I sequence in the NT-SC embryos was more demethylated than that in the donor cells. Although the DNA methylation level in the individual NT-SC embryos showed variation, the full-term developmental efficacy of these embryos were not different. These findings suggest that the methylation level of the satellite I sequence at the BC stage is not related to the abnormalities of bovine embryos produced by NT-SC. There was no difference in methylation levels between Re-NT and NT-SC embryos. Our results indicated that the DNA methylation status differed among embryos produced by various methods and that at least some of the demethylation of the donor cell genome occurred in the recipient cytoplast after NT-SC, but the demethylation ability of the NT procedure was noted in the first NT but not in the second NT.     

The functional effect of Gly209 and Ile213 substitutions on lysozyme activity of family 19 chitinase encoded by cyanophage Ma-LMM01

ORF69 in the cyanophage infecting Microcystis aeruginosa, Ma-LMM01, shows homology to the family 19 chitinases where the catalytic domain has structural similarity to lysozyme. Chitinases hydrolyze chitin, a β-1, 4-linked monopolymer of N-acetylglucosamine (GlcNAc); whereas lysozymes hydrolyzes peptidoglycan, alternating β-1, 4-linked copolymers of N-acetylmuramic acid (MurNAc) and GlcNAc. Using amino acid sequence comparison to ORF69, the putative sugar binding residues, Gln162 and Lys165, from the barley chitinase (the model enzyme for the family 19 chitinases) corresponding to subsites −4 and −3 were found to be replaced with Gly209 and Ile213, respectively, in ORF69. To analyze their contribution to substrate binding affinity, ORF69 was cloned into Escherichia coli; and two mutant proteins G209Q and I213K were prepared using site-directed mutagenesis. The wild-type gene product (gp69) showed both lysozyme and chitinase activities. In contrast, the I213K mutant showed a decrease (70%) in lysozyme activity and a significant increase (50%) in chitinase activity; whereas, the G209Q mutant almost completely abolished both enzyme activities. The data suggest the Ile213 residue is involved in recognizing the substrate MurNAc; and Gly209 has significant contribution in chitinase and lysozyme activities for the wild-type gp69.     

A new method for measuring microbial biomass nitrogen in soils: Direct extraction after toluene treatment

Abstract

Phenolic compounds occurring naturally are reducing agents which react with hydrous Fe oxide and Mn oxides (Lehmann et al. 1987). Diphenols such as hydroquinone, resorcinol, and catechol were oxidatively darkened by the presence of hydrous Fe oxide though the degree of darkening was much less pronounced than that by Mn oxides (Shindo and Huang 1984). Okazaki et al. (1976) suggested that polyphenols are one of the materials responsible for the dissolution of Mn in a paddy soil under reducing conditions.