Characterization of Aquimarina hainanensis isolated from diseased mud crab Scylla serrata larvae in a hatchery

Mass mortality due to necrosis signs occurred in hatchery-reared zoea stage larvae of the mud crab Scylla serrata in Okinawa, Japan, and a causative bacterium was isolated. In this study, we identified and characterized the bacterium by genome analysis, biochemical properties and pathogenicity. The bacterium was a Gram-negative, non-motile, long rod, forming yellow colonies on a marine agar plate. It grew at 20–33°C (not at 37°C) and degraded chitin and gelatin. Phylogenetic analysis of the 16S rRNA gene sequence identified the bacterium as Aquimarina hainanensis. Genome sequence data obtained from Illumina MiSeq generated 29 contigs with 3.56 Mbp in total length and a G + C content of 32.5%. The predicted 16 chitinase genes, as putative virulence factors, had certain homologies with those of genus Aquimarina. Experimental infection with the bacterium conducted on larvae of four crustacean species, brine shrimp Artemia franciscana, freshwater shrimp Caridina multidentata, swimming crab Portunus trituberculatus and mud crab S. serrata, revealed that this bacterium was highly virulent to these species. The present study suggests that the bacterium caused mass mortality in mud crab seed production was A. hainanensis and can be widely pathogenic to crustaceans.     

The Effect of Methanolic Valeriana officinalis Root Extract on Adipocyte Differentiation and Adiponectin Production in 3T3-L1 Adipocytes

Plant Foods for Human Nutrition - Adipose tissue is an endocrine organ and its endocrine function is closely associated with type 2 diabetes mellitus. Valeriana officinalis (Valerian) exerts some...     

Comparison of morphological and DNA-based techniques for stomach content analyses in juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis>: a case study on diet richness of juvenile fishes

To identify the stomach contents of marine organisms, morphological observations are commonly conducted. However, the results obtained by this traditional method are frequently biased, as it is difficult to detect partially digested, soft-bodied organisms. To resolve this, recent studies have used DNA-based (DNA barcoding) analyses to examine the diet breadth of marine organisms. Here, we compared the prey richness of juvenile fishes using morphological observations and DNA-based analyses, with a focus on juvenile chum salmon Oncorhynchus keta. A higher number of prey taxa were successfully identified using DNA-based analyses than morphological observations. However, we also noticed several shortcomings of the DNA-based analyses, as reported in other diet-analysis studies that used molecular techniques. For example, the degree of digestion among prey taxa might have resulted in differential sensitivity to DNA detection. Additionally, several prey taxa could not be precisely identified, as the sequence data for some of the targeted organismal groups are unavailable in public gene databases. Remarkably, it is also possible that DNA-based analyses detected secondary prey, and therefore, the richness of prey taxa was likely overestimated. Thus, dietary analyses of juvenile fishes need to be carefully conducted, considering the respective advantages and disadvantages of DNA-based and morphological techniques.     

Alteration of somatostatin receptor 2 expression in canine mammary gland tumor

Somatostatin receptor 2 (SSTR2) is a negative regulator of cell proliferation in human breast cancer. Since there is little information about SSTR2 in canine mammary gland tumor (MGT), we clarified its distribution and expression level in normal mammary gland, benign MGT and malignant MGT. SSTR2 expression determined by immunohistochemical staining was observed in the cytoplasm of luminal epithelial cells. The intensity was negatively correlated with malignancy: normal tissues and some of the benign tumors had the highest levels, while the malignant tumors had little or no SSTR2 expression. As for the Western blotting, SSTR2 protein level in benign tumors was significantly lower than the normal mammary gland. On the other hand, SSTR2 protein levels in two of three malignant tumors were higher than the other groups. These results suggest that SSTR2 expression alters according to the malignancy of canine MGT.     

The effect of strain, growth stage, and cultivating condition of Ganoderma lucidum on 5α-reductase inhibition

The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested.     

Growing situation of afforested trees and damage to lower-story trees caused by felling in multi-storied forest management in Peninsular Malaysia

The growing condition of afforestation trees and damage to lower-story trees caused by felling and hauling of upper-story trees in a multi-storied forest in Peninsular Malaysia was surveyed. Seventy months have passed since the planting ofAcacia mangium upperstory trees, which have grown 233 m³/ha in volume. The growth ofShorea leprosula thirty-five months after planting of lower-story trees have reached 5.54 m in height. However, as the ratio of height to basal diameter exceeds 100:1, trees are tapering to a considerable degree. A backhoe was installed in order to fell the upper-story trees. From the results of logging, the damage ratio estimation of the lower-story trees was simulated by using the Monte Carlo method. The damage ratio differed considerably depending on planting patterns, height of upper-story trees and felling skills. The results of this survey proved that the felling and hauling of upper-story trees would be technically feasible in the future, except when one row upper-story trees and one row lower-story trees method were employed.     

A method for isolation of milled-wood lignin involving solvent swelling prior to enzyme treatment

Summary A new lignin isolation method has been developed. Wood and pulp were subjected to ball milling, swelled in an organic solvent, and then treated with a cellulase. The enzyme digestion time could be shortened to 1 day with this method. The lignin obtained has been named Swelled Enzyme Lignin (SEL). Swelling and enzyme digestion conditions and their effects on lignins were investigated. The SEL's from wood could be directly washed with water, while those from pulp had to be washed with aqueous acetic acid because they were water soluble. The purification of crude SEL's was accomplished by extracting them with dioxane-water, and then precipitating and washing with ethyl ether. Lignin yields were 24–67% based on the total amount of lignin present. The characteristics of the SEL's were further investigated by gel-permeation chromatography (GPC), infrared and ¹³C nuclear magnetic resonance (NMR) spectroscopy.Symbols SUKP Softwood Unbleached Kraft Pulp - BUKP Birch Unbleached Kraft Pulp - TD Todomatsu (Abies sachalinensis) wood - MWL Milled Wood Lignin - MWLS (BK, TD) Milled Wood Lignin of SUKP (BUKP, TD) - SEL-C Swelled Enzyme Lignin (crude) - SELS-C SEL-C of SUKP, other materials named in the same way - SELS-90 SEL-C of SUKP and extracted with 90% dioxane-water - SELS-96 SEL-C of SUKP and extracted with 96% dioxane-water, other materials named in the same way     

Screening of extracts of Japanese woods for melanin biosynthesis inhibition

The effects of 120 methanol extracts prepared from bark and heartwood of 69 types of Japanese wood on the melanin production of B16 melanoma cells were examined. The melanin content of B16 melanoma cells was determined spectrophotometrically at 405nm. The extracts were also examined for their effects on cell viability. We found that the methanol extracts of Fagus crenata (buna, wood, 100μg/ml), Sapium sebiferum (Nankinhaze, wood, bark, 10μg/ml), and Zelkova serrata (keyaki, wood, 10μg/ml) greatly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity. However, these extracts did not inhibit tyrosinase activity at the concentration of 100μg/ml. These findings indicate that the depigmenting mechanism of these extracts involves the suppression of some pigmenting signals in stimulating melanogenesis rather than the inhibition of tyrosinase activity. Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003