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This study aimed to determine the potential impact of an oil spill on intertidal meiofauna at a clean, sandy beach in Korea. This objective was accomplished by examining changes in the structure of meiofaunal assemblages after a controlled oil spill of different concentrations on the beach. The concentration of total petroleum hydrocabon (TPH) in the experimental plots after oil application was expectedly higher for the first 4 d compared to before oil application. The TPH concentrations decreased at a faster rate in the first 4 d, and then progressively. The sharp decline in meiofaunal density in the experimental plots during the first 4 d after the spill might be attributed to the short-term toxic effects of the oil. This suggestion is supported by a significant negative interaction of the TPH on meiofaunal density during the study period. The period of low density of meiofauna also coincided with the maximum concentration of TPH in the sediment. The multivariate indices proved to be highly efficient, showing that samples contaminated with oil had high TPH concentrations, and were partially separated in terms of meiofaunal communities from samples before oil application or samples with low TPH concentrations. The structure of the meiofaunal communities in the experimental plots was similar before and 1 month after oil application. However, the density of meiofauna sharply decreased immediately after oil application in the experiment plots. Furthermore, the meiofaunal density recovered slowly as time passed. [ABSTRACT FROM PUBLISHER]

The article discusses mobile oxygen vacancies offering a substantial potential to broaden the range of optical functionalities of complex transition metal oxides due to high mobility and the interplay with correlated electrons. Topics include the coloration efficiency reaches ~80 cm2 C−1, means that a 300-nm-thick layer blocks 99% of transmitted visible light by the electrical switching; and the transparent BM-CFO has changed to a highly conducing dark-colored P-CFO.

Topological textures of ferroelectric polarizations have promise as alternative devices for future information technology. A polarization rotation inevitably deviates from the stable orientation in axial ferroelectrics, but local energy losses compromise the global symmetry, resulting in a distorted shape of the topological vortex or inhibiting the vortex. Easy planar isotropy helps to promote rotating structures and, accordingly, to facilitate access to nontrivial textures. Here, we investigate the domain structure of an epitaxial thin film of bismuth tungsten oxide (Bi 2 WO 6 ) grown on a (001) SrTiO 3 substrate. By using angle-resolved piezoresponse force microscopy and scanning transmission electron microscopy, we find the existence of a hidden phase with ⟨100⟩-oriented ferroelectric polarizations in the middle of the four variant ⟨110⟩-oriented polarization domains, which assists in the formation of flux closure domains. The results suggest that this material is one step closer to becoming an isotropic two-dimensional polar material.

Styphnolobium japonicum (L.) is utilized in Korean medicine for the treatment of various inflammatory diseases. The aim of the present study was to explore the effects of Fructus sophorae extract (FSE) isolated from the dried ripe fruit of S. japonicum (L.) on the development of type II collagen-induced arthritis (CIA) in BALB/c mice. The CIA mice were orally administered FSE or saline daily for 2 weeks. The incidence and severity of disease and the inflammatory response in the serum and the joint tissues were assessed. Macroscopic and histological investigation indicated that FSE protected against CIA development. FSE was associated with a significant reduction in the levels of total immunoglobulin G2a and proinflammatory cytokines and mediators in the serum. In addition, FSE suppressed the gene expression levels of proinflammatory cytokines and mediators, the mediator of osteoclastic bone remodeling, the receptor activator of nuclear factor κ-B ligand and matrix metalloproteinases in the joint tissues. The present results suggest that FSE may protect against inflammation and bone damage, and would be a valuable candidate for further investigation as a novel anti-arthritic agent.

Objective: To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants., Methods: Mangrove samples were harvested at the shoreline on the island of Weno, Chuuk State in Micronesia. The phenol content, antioxidant activity (based on DPPH-free radical scavenging) and tyrosinase inhibitory activity in different tissues (leaves, barks and roots) of Rhizophora stylosa (R. stylosa) and Sonneratia alba (S. alba), collected from the island of Weno., Results: Total phenol content ranged from 4.87 to 11.96 mg per g of freeze dried samples. The highest antioxidant activity was observed in R. stylosa bark (85.5%). The highest tyrosinase inhibitory activity was found in S. alba bark. Also, total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts., Conclusions: Taken together, the results of this study proved that mangroves can be excellent sources of antioxidant compounds., (Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.)

An aerobic, Gram-negative, coccoid to short rod-shaped and non-flagellated marine bacterial strain S354(T) was isolated from seawater of Micronesia. The strain was capable to degrade agar-forming slight depression into agar plate. Growth occurred at a temperature range of 12-44 °C, a pH range of 5-9, and a salinity range of 1-7 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences suggested that S354(T) belongs to the family Flammeovirgaceae. The novel strain was most closely related to Limibacter armeniacum YM 11-185(T) with similarity of 92.5 %. The DNA G+C content was 43.8 mol%. The major fatty acids (>10 %) were iso-C15:0 and C16:1 ω5c. The predominant isoprenoid quinone was determined to be MK-7. Polar lipid profile of S354(T) consisted of phosphatidylethanolamine, unknown polar lipid, and unknown glycolipids. Based on the phenotypic, phylogenetic, biochemical, and physiological tests conducted in this study, S354(T) is proposed to represent a type strain of a novel genus and species. The 16S rRNA gene sequence of S354(T) is registered in GenBank under the accession number JQ639084. The type of strain Algivirga pacifica gen. nov., sp. nov. is S354(T) (=KCCM 90107(T)=JCM 18326(T)).

Petroleum hydrocarbon contamination and macrobenthos in the sandy tidal flats of Taean were monitored for 1 year to assess the impacts of Hebei Spirit oil on the macrobenthic community. A total of 207 macrobenthic fauna was collected, and the mean density and biomass of macrobenthic fauna continued to decrease until 12 months after the oil spill, but macrobenthic density at the most heavily affected sites increased by about twofold. In January 2008, the dominant species occurred at very low densities in strongly affected sites. The macrobenthic communities differed between oil-affected and unaffected sites. In particular, differences in community structure at Mallipo beach were larger than those at Shinduri. We suggest that long-term monitoring is needed to assess the specific effects of oil pollution on the sandy intertidal macrobenthic community., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Bioassays and biomarkers have been previously developed to assess the effects of heavy metal contaminants on the early life stages of the sea urchin. In this study, malformation in the early developmental processes was observed in sea urchin (Strongylocentrotus intermedius) larvae exposed to 10 ppm Ni for over 30 h. The most critical stage at which the triggering of nickel effects takes place is thought to be the blastula stage, which occurs after fertilization in larval development. To investigate the molecular-level responses of sea urchin exposed to heavy metal stress and to explore the differentially expressed genes that are induced or repressed by nickel, differential display polymerase chain reaction (DD-PCR) was used with sea urchin mRNAs. The malformation-related genes expressed in the early life stages of the sea urchin were cloned from larvae exposed to 10 ppm of nickel for 15 h, and accessed via DD-PCR. Sequence analysis results revealed that each of the genes evidenced high homology with EGF2, PCSK9, serine/threonine protein kinase, apolipophorin precursor protein, and MGC80921 protein/transcript variant 2. This result may prove useful in the development of novel biomarkers for the assessment of heavy metal stresses on sea urchin embryos., (Copyright © 2012 Elsevier Inc. All rights reserved.)

In this study, we isolated xylan-degrading bacteria from a coastal lagoon of Micronesia and identified the bacteria as Marinobacterium stanieri S30. GSFLX 454 pyrosequencing and sequence analysis of the M. stanieri S30 genome generated 4,007 predicted open reading frames (ORFs) that could be candidate genes for producing enzymes with different catalytic functions.

The disk abalone Haliotis discus discus and the spiny top shell Turbo cornutus are edible gastropod species of high economic value, mainly in Asia. Mortality outbreaks and variations in worldwide stock abundance have been reported and suggested to be associated, at least in part, with pathogenic infections. Ecology, biology and immunology of both species are currently not well documented. The characterisation of the immune systems of these species is necessary to further assess the responses of H. discus discus and T. cornutus to environmental, chemical and disease stresses. In the present study, we investigated the morphology and immune-related activities of hemocytes in both species using light microscopy and flow cytometry. Two types of hemocytes were identified in the disk abalone hemolymph, blast-like cells and hyalinocytes; whereas four main hemocyte types were distinguished in the spiny top shell, blast-like cells, type I and II hyalinocytes, and granulocytes. Flow cytometric analysis also revealed differences between cell types in immune-related activities. Three subsets of hemocytes, defined by differing lysosomal characteristics, were observed in the hemolymph of the spiny top shell, and only one in the disk abalone. Phagocytic activity was higher in H. discus discus hemocytes than in T. cornutus hemocytes, and the kinetics of PMA-stimulated oxidative activity was different between hemocytes of the disk abalone and the spiny top shell. Finally our results suggest for the first time a predominant mitochondrial origin of oxidative activity in gastropod hemocytes., (Copyright 2009 Elsevier Ltd. All rights reserved.)

In the present study, three kinds of phlorotannins, marine algal polyphenol, were isolated from a brown alga Ecklonia cava, and their inhibitory effect on melanogenesis as well as the protective effect against photo-oxidative stress induced by UV-B radiation was investigated. The effect on melanogenesis was evaluated via the inhibitory effects of tyrosinase and melanin synthesis. Among the phlorotannins, dieckol showed higher effect than that of the other phlorotannins in the both assays; especially the value of dieckol in the tyrosinase inhibition assay was relatively higher than that of a commercial tyrosinase inhibitor (kojic acid). The UV-B protection effect was evaluated via DCFH-DA, MTT, comet assays, and morphological changes in fibroblast. Intracellular ROS induced by UV-B radiation was reduced by the addition of phlorotannins and cell viability was dose-dependently increased. Moreover, dieckol demonstrated strong protective properties against UV-B radiation-induced DNA damage via damaged tail intensity and morphological changes in fibroblast. Hence, these results indicated that dieckol isolated from E. cava has potential whitening effects and prominent protective effects on UV-B radiation-induced cell damages, which might be used in pharmaceutical and cosmeceutical industries.

The Suminoe oyster Crassostrea ariakensis has been attempted to be introduced in the Chesapeake Bay, USA, as an alternative to the eastern oyster Crassostrea virginica. Commercial production of Suminoe oysters is currently restricted due to the incomplete understanding of their biological, physiological and immunological nature. Accordingly, understanding immune system of C. ariakensis is crucial to prevent disease associated mortality and subsequent management of the Suminoe oyster. We investigated immunological activities and morphology of hemocytes of the Suminoe oyster using flow cytometry and light microscopy. Three types of hemocytes were identified in the hemolymph including hyalinocyte, granulocyte and blast-like cells. Hyalinocytes were the largest cells and the most abundant, while granulocytes were intermediate-size cell containing numerous granules in the cytoplasm. Blast-like cells were the smallest and least numerous. Flow cytometry revealed that the granulocytes are most active in the cell phagocytosis and spontaneous reactive oxygen species (ROS) production. The hyalinocytes also showed a certain level of the phagocytosis and oxidative activity but in a lesser extent than the granulocytes. In contrast, the blast-like cells did not show any phagocytosis or oxidative activity. The flow cytometry used in this study confirmed that as observed from other marine bivalves, the granulocytes are the main hemocytes involved in the cellular defence in the Suminoe oyster.

Changes in soft-bottom macrobenthic communities and the effects of anthropogenic disturbances were studied. We compared biological and environmental samples during and after bridge construction (DBC and ABC). Significant differences were detected in sediment composition at three stations, although hydrographic conditions were similar for DBC and ABC samples. From DBC to ABC, the number of species and density of macrobenthic fauna tended to decrease, whereas biomass increased. Non-metric multidimensional scaling (MDS) analysis identified two sampling period groups from eight temporal samples, plus three station groups and one station from 12 spatial samples, which corresponded to macrobenthic faunal assemblages and theircharacteristic species. In addition, contributions of variables to similarity showed that the DBC and ABC samples differed significantly in the distribution of characteristic species and proportion of polychaete trophic groups, suggesting that the macrobenthic community structure was a factor affecting sediment disturbance caused by bridge construction.