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101.
Seco-chaetomugilins A and D were isolated from a strain of Chaetomium globosum that was originally isolated from the marine fish Mugil cephalus, and their absolute stereostructures were elucidated on the basis of spectroscopic analyses, including 1D and 2D NMR techniques, along with the chemical transformation from known chaetomugilins A and D. Seco-chaetomugilin D exhibited growth inhibitory activity against cultured P388, HL-60, L1210, and KB cells.  相似文献   
102.
Aji-no-susu is a Japanese fermented fish product prepared from salted horse mackerel Trachurus japonicus, and cooked rice. We studied the organic acid and free amino acid contents and microflora in 12 aji-no-susu products to clarify their features as a lactic-acid-fermented food. Salinity of the samples was approximately 7.0% (rice portion) and 6.0% (fish portion) (w/w). Water activity was approximately 0.9, and pH was approximately 4.4 and lower. In the rice portions, lactic acid content was very high (57 mg/g sample). The predominant amino acids were alanine (2.3 mg/g rice portion) and lysine (2.1 mg/g). In the case of long-fermented (4 and 12 months) aji-no-susu, a high content of gamma-aminobutyric acid (GABA, 1.5 and 1.4 mg/g) was detected. Total viable counts in rice and fish portions were 7.7 and 7.4 log colony-forming units (cfu)/g, respectively. The number of lactobacilli in the rice and fish portions was 7.3 and 7.1 log cfu/g, respectively. Yeasts were detected in eight samples. Furthermore, acid-tolerant lactic acid bacteria (LAB) (Lactobacillus plantarum), GABA-producing LAB (Lactobacillus sp.), and halophilic or halo-tolerant yeast (Debaryomyces hansenii) were isolated and identified. Results in this study indicate that aji-no-susu is a typical traditional lactic-acid-fermented fish product.  相似文献   
103.
Japanese people consume crop bran, which contains relatively high amounts of gamma-oryzanol (ORZ), as foodstuffs and food materials. We have recently confirmed that ORZ inhibits NF-κB activation, activates peroxisome proliferator-activated receptor gamma (PPARγ), and increases plasma adiponectin levels. ORZ is therefore expected to improve lipid and carbohydrate metabolisms and various inflammatory diseases, i.e., metabolic syndrome including type 2 diabetes. ORZ administration also allowed fish, such as rainbow trout, yellowtail, and red sea bream, to accumulate protein through enhancement of lipid and carbohydrate metabolisms. In the present study, we have investigated ORZ accumulation levels in mouse and rainbow trout administered ORZ-containing feed. Although mouse muscle and liver hardly contained ORZ, muscle tissues of every fish species accumulated higher amounts of ORZ. These findings suggest that rainbow trout, red sea bream, and yellowtail accumulate ORZ in muscle.  相似文献   
104.
The enzymatically dehydrogenative polymerization of coniferyl aldehyde and coniferyl alcohol was studied to understand lignins in cinnamyl alcohol dehydrogenase (CAD)-downregulated plants. The sample dimers were prepared by polymerization under three reaction systems (coniferyl alcohol, coniferyl aldehyde, and their combination) with horseradish peroxidase/H2O2 under the conditions of limited reaction time. In addition, the residual amount of substrate in each reaction was determined at specified time intervals. In the reaction system of coniferyl aldehyde, the 5-5-type dimer was formed in preference to- and-5 dimers; in the reaction system of coniferyl alcohol the-5 dimer was preferentially formed. Furthermore, it was revealed when quantifying dimers among reaction systems that the total dimer formation capability of coniferyl alcohol clearly surpassed that of coniferyl aldehyde. However, the dimers cross-coupled with coniferyl alcohol and coniferyl aldehyde were formed in amounts not accounted for by the difference seen in dimer formation abilities with the two substrates.Part of this paper was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   
105.
The somatic chromosomes of standard indica diploid rice, IR 36, were squashed on glass slides and stained with Giemsa. The condensation patterns (CP) of prometaphase chromosomes were quantitatively analysed using CHIAS III software. The relative length and centromeric index (CI) were converted from CHIAS III to numerical data and calculated by EXCEL program. The ideogram based on CP of indica rice was established. There were 2 pairs of satellite chromosomes and the result was confirmed by fluorescence in situ hybridization using 45S rDNA as a probe. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
106.
Feeding sites for wild Yeso sika deer around Lake Akan, Japan, were established. Effects on the number of deer using the feeding sites, the prevention of bark stripping damage, the amount of feeding, and eating time in a 5‐year period (1999–2003) were evaluated. The number of deer using feeding sites increased with years during the feeding period. The damaged tree ratio after the initiation of feeding markedly decreased compared with 16.5% before the initiation of feeding. After the start of feeding, there were no trees with damage the entire circumference. According to tree species, the number of damaged trees of Ulmus laciniata Mayr as a percentage of all investigated trees was high (5.2%). The total amount of beet pulp feeding increased with the feeding year, showing 4.5‐fold increase. At feeding sites in deer culling, eating behavior was observed during the night. The preventive effects on bark stripping damage continued during the 5‐year feeding period. However, with the course of feeding years, the number of deer using feeding sites and the level of feeding increased.  相似文献   
107.
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109.
Activation-induced cytidine deaminase (AID) is required for the DNA cleavage step in immunoglobulin class switch recombination (CSR). AID is proposed to deaminate cytosine to generate uracil (U) in either mRNA or DNA. In the second instance, DNA cleavage depends on uracil DNA glycosylase (UNG) for removal of U. Using phosphorylated histone gamma-H2AX focus formation as a marker of DNA cleavage, we found that the UNG inhibitor Ugi did not inhibit DNA cleavage in immunoglobulin heavy chain (IgH) locus during CSR, even though Ugi blocked UNG binding to DNA and strongly inhibited CSR. Strikingly, UNG mutants that had lost the capability of removing U rescued CSR in UNG-/- B cells. These results indicate that UNG is involved in the repair step of CSR yet by an unknown mechanism. The dispensability of U removal in the DNA cleavage step of CSR requires a reconsideration of the model of DNA deamination by AID.  相似文献   
110.
Abstract

A number of clusters of resting spores of an endophyte were found to have colonized the nodal root axes and first order lateral roots of sorghum at the heading stage. The clusters with a diameter ranging 15 to 20 μm consisted of a number of spores with a diameter in the range of 2 to 5 μm. Based on the morphological characteristics, the endophyte was tentatively assigned to Polymyxa sp. The clusters were distributed in the epidermis and the hypodermis, but mostly in the latter. The clusters were absent in the tissues internal to the hypodermis. The number of cells colonized by the clusters in the hypodermis, the hypodermal cell lignification identified by the phloroglucinol-HCl test, and the cortical sclerenchyma development were examined acropetally in three nodal roots which emerged from the third node. The colonized cells accounted for less than about 10% of the total number of the hypodermal cells in the first 8 cm portion, but beyond this part, their number increased and they accounted for 10 to 35%. Hypodermal cell lignification and cortical sclerenchyma development were clearly recognized approximately in the first 9 and 6 cm portion, respectively, but they were not observed beyond this part. Even in this portion, however, no endophyte colonization was observed in any tissues internal to the hypodermis. These findings suggest that in sorghum the hypodermis itself, regardless of cell lignification, may function as a barrier to protect the inner tissues from further colonization by the spore clusters of Polymyxa sp.  相似文献   
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