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Coral reef ecosystems supported by environmentally sensitive reef-building corals face serious threats from human activities. Our understanding of these reef threats is hampered by the lack of sufficiently sensitive coral environmental impact assessment systems. In this study, we established a platform for metabolomic analysis at the single-coral-polyp level using state-of-the-art mass spectrometry (probe electrospray ionization/tandem mass spectrometry; PESI/MS/MS) capable of fine-scale analysis. We analyzed the impact of the organic UV filter, benzophenone (BP), which has a negative impact on corals. We also analyzed ammonium and nitrate samples, which affect the environmental sensitivity of coral-zooxanthella (Symbiodiniaceae) holobionts, to provide new insights into coral biology with a focus on metabolites. The method established in this study breaks new ground by combining PESI/MS/MS with a technique for coral polyps that can control the presence or absence of zooxanthellae in corals, enabling functions of zooxanthellae to be assessed on a polyp-by-polyp basis for the first time. This system will clarify biological mechanisms of corals and will become an important model system for environmental impact assessment using marine organisms. [ABSTRACT FROM AUTHOR]

While this collection of articles provides a pathbreaking assemblage of studies of Japanese diaspora, for the progression of the field, archaeology must engage critically with other disciplines. Too often historical archaeology is conceived of as an afterthought or curiosity in conjunction with other disciplines' approaches to history. Materials and objects as illustrative but not informative to the level of the archive of oral historical record. In this concluding forum, we discuss the contribution of archaeology to Japanese Diaspora studies, inviting a diverse group of scholars to comment on this special issue. What relevance do these studies have, and how do they articulate with other disciplinary approaches? In doing so we hope to move the conversation beyond the discipline, putting archaeology in dialogue with history, cultural anthropology, and ethnic studies. [ABSTRACT FROM AUTHOR]

This paper examines the way considerations of race factored into the colonisation of Hawai'i and its subsequent governance of immigration and different racial groups. Throughout the nineteenth century, the Kingdom of Hawai'i faced unprecedented demographic change due to its rapidly declining native population and inflows of people from abroad. To preserve its sovereignty, the kingdom attempted to forge solidarity with Japan and Samoa governed by nonwhite people under threat of Western colonisation. Although official rule by European and American settlers did not start until the overthrow of the Hawaiian Kingdom in 1893, they steadily expanded their influence over Hawaiian politics and economy by monopolising the sugar industry. Wary of the effects of nineteenth-century geopolitics, the kingdom attempted to resist the establishment of a white-dominated society that pursued its political, economic, and social agenda through the management of sugar plantations and the opening up of immigration. In the process of stabilising and maintaining the kingdom's sovereignty in the late nineteenth century, nonwhiteness became a significant racial foundation to confront the white dominance in the Islands and to establish an ally with nonwhite peoples and nations in the Asia-Pacific basin. [ABSTRACT FROM AUTHOR]

Over the past several decades, coral reef ecosystems have experienced recurring bleaching events. These events were predominantly caused by thermal anomalies, which vary widely in terms of severity and spatio-temporal distribution. Acropora corals, highly prominent contributors to the structural complexity of Pacific coral reefs, are sensitive to thermal stress. Response of Acropora corals to extremely high temperature has been well documented. However, studies on the effects of moderately high temperature on Acropora corals are limited. In the summer of 2016, a moderate coral bleaching event due to moderately high temperature was observed around Sesoko Island, Okinawa, Japan. The objective of this study was to examine thermal tolerance patterns of Acropora corals, across reefs with low to moderate thermal exposure (degree heating weeks ~2–5°C week). Field surveys on permanent plots were conducted from October 2015 to April 2017 to compare the population dynamics of adult Acropora corals 6 months before and after the bleaching events around Sesoko Island. Variability in thermal stress response was driven primarily by the degree of thermal stress. Wave action and turbidity may have mediated the thermal stress. Tabular and digitate coral morphologies were the most tolerant and susceptible to thermal stress, respectively. Growth inhibition after bleaching was more pronounced in the larger digitate and corymbose coral morphologies. This study indicates that Acropora populations around Sesoko Island can tolerate short-term, moderate thermal challenges. [ABSTRACT FROM AUTHOR]

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase involved in many cellular functions including cell growth and migration. EGFR may be activated by EGF family ligands such as EGF and epiregulin (EREG). EREG is overexpressed in human colon and breast cancers, implying that EREG plays roles in tumorigenesis. Although EGF family members share a receptor, it is not well known whether their signaling pathways differ. In order to investigate EREG signaling, we established the anti-EREG antibody that inhibits EGFR downstream signaling stimulated by EREG but not by EGF. While the anti-EREG antibody has little effect on cell growth, it inhibits cell adhesion of EREG-expressing autocrine cancer cell lines. Our results suggest that anti-EREG antibodies represent valuable tools for elucidating EREG-specific signaling pathways, and may serve as therapeutic candidates for the treatment of cancers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Epiregulin may be highly relevant for therapeutic applications. [•] We generated humanized anti-epiregulin antibodies by resurfacing the variable region. [•] Our method identified residues that critically affect antigen binding. [•] Our HM1 antibody had high-affinity targeted cytotoxicity against colon cancer cells. [ABSTRACT FROM AUTHOR]

Our previous study revealed that exposure to 0.4 ppm ozone (O3) enhanced nasal allergy-like reactions in guinea pigs. In the present study, we investigated the concentration-dependency of the effects of exposure to O3 on the aggravation of nasal allergy-like reactions induced by repeated nasal administration of antigen. Guinea pigs were exposed to filtered air or 0.1–0.6 ppm O3 for 5 weeks. After each weekly administration of ovalbumin (OVA), sneezes and nasal secretions were measured. The number of eosinophils infiltrating the nasal septum and the titers of OVA-specific antibody were measured 24 h after the last administration. Ozone increased sneezing and nasal secretion induced by OVA, nasal responsiveness to physical stimuli, and the number of infiltrating eosinophils in a concentration-dependent manner. The titer of anti-OVA-IgG was increased in animals exposed to 0.6 ppm O3. Thus, exposure to O3 aggravated nasal allergy-like symptoms concentration dependently. The aggravation was caused by induction of nasal hyperresponsiveness, the infiltration of eosinophils, and the increase in the production of anti-OVA-IgG. The estimated maximum likelihood estimation concentrations (MLECs) and bench mark concentrations (BMCs) of O3 for these indices were in the range of 0.09–0.18 and 0.02–0.06 ppm, respectively. [Copyright &y& Elsevier]

Since the beginning of the last century, bacteria, including cyanobacteria, have been known to be involved in the extracellular formation and precipitation of CaCO3. It is also known that some marine bacteria form calcite granules in Ca-containing artificial media. However, a detailed analysis of these granules has not yet been performed. The objective of the present study was to isolate marine bacteria that form CaCO3 granules in a culture medium to analyze the structure of the granules in detail. Pseudovibrio sp. 01OK 105-5-5, belonging to the class Alphaproteobacteria, was isolated from an ascidian in a coral reef at On-na, Okinawa, Japan. It produced extracellular granules of CaCO3 in a Ca-containing artificial medium. X-ray diffraction analysis, infrared spectroscopy, and inductively coupled plasma atomic emission spectrometry demonstrated that the extracellular granules contained Mg-rich calcite-like crystal polymorphs. This crystal form of CaCO3 was similar to that of Mg-rich calcite found in the skeletons of many marine invertebrates. This bacterium provides a promising tool for studying the mechanisms involved in the formation of Mg-rich biogenic calcite. [ABSTRACT FROM AUTHOR]

Calcareous skeletons of stony corals are composed of a low-crystalline core (center of calcification: COC) and surrounding fibrous crystals. We characterized the overall framework of juvenile Acropora digitifera corals to clarify the entire calcic architecture and the contribution of abiotic processes. Skeletal and tubular frameworks contain string and sheet COCs, respectively, consisting of strained aragonite nanograins. Parallel and curved structures of fibrous aragonite develop around the COC cores through geometric selection and a gradual change in the growth direction of the c-direction-elongated nanorods. Based on a study of the nanoscale morphology of the coral frameworks by comparing them to fibrous crystals grown in artificial systems, it appears that subsequent precipitation of the fibrous aragonite on the COC is primarily regulated by environmental abiotic parameters. The architecture of the COC network is deduced to be designed biologically and then thickened by the fibrous crystals that are produced with morphology formation through physicochemical processes although the vital activity controls the total mineralization. [ABSTRACT FROM AUTHOR]

Bacterial communities are important factors governing changes in river ecology. We evaluated the diversity of bacterial communities in sediment and size-fractionated water samples collected from the Tama River, Tokyo, Japan, to verify their taxonomy and functional classes. Samples were collected from three river areas, namely up-, mid- and downstream, and analyzed using MiSeq shotgun metagenomic sequencing. Bacterial diversity in the river water was highest midstream for the free-living bacterial communities. Dominant bacterial classes upstream were Alphaproteobacteria and Betaproteobacteria, and there was a gradual shift to dominance by Actinobacteria mid- and downstream. Potential pathogenic genera, such as Flavobacterium, Mycobacterium and Bacteroides, also dominated mid- and downstream. Interestingly, Mycobacterium was most abundant midstream, whereas Pseudomonas was observed upstream. The gene possibly associated with sulfur metabolism, sigB, and those associated with purine metabolism, purF, purD, purN, purH, guaB and guaA, dominated in the bacterial communities found mid- and downstream and are thought to ensure survival and virulence in their environments. NO2-N, NH4-N and PO4-P were found to influence bacterial populations in water but not those residing in the sediment. [ABSTRACT FROM AUTHOR]

• The source of nitrate pollution was studied in subsurface dammed limestone aquifers. • N and O isotopic tracers of nitrate were applied for identifying pollution source. • Solvable fractions of farmland soils were extracted and measured for isotope ratios. • Soil samples are useful as reference materials for precise source identification. • Updated knowledge on the pollution source was proposed for the studied aquifers. Nitrate contamination of groundwater due to improper management of fertilizer application and controls during agricultural activities is an escalating worldwide issue. Numerous studies have reported similar contamination in the Ryukyu limestone aquifer in the southern part of Okinawa Island. The study area has a unique setting where the subsurface dams hold the groundwater behind their cut-off walls, probably holding contaminated waters. This study provides updated insights on the source of contamination using stable N and O isotope ratios of dissolved nitrate (ẟ15N NO3 and ẟ18O NO3) in the aquifer waters. To propose a better reference in the source fingerprinting assessment, a special emphasis was placed on the isotopic comparison between the fertilizers and farmland soils where the respective fertilizers were applied. A total of 176 groundwater samples were collected from several spatial and monthly sampling campaigns for the purpose of source determination. Our isotopic comparison detected the enrichment of 15N of nitrate-nitrogen in the soil samples after the application of both chemical fertilizers and manure due to nitrification and volatilization. Unlike results from previous studies, the ẟ15N NO3 compositions of most groundwater samples did not fall into the range of soils mainly controlled by chemical fertilizers (from +3‰ to +5‰), but were comparable to the soils affected by mixed fertilizers including both chemical fertilizers and manure (from +7‰ to +9‰). The soils beneath untreated manure storage sites characterized by the highest ẟ15N NO3 values (from +18‰ to +20‰) affected some groundwater, which shows an even higher value (> +9‰). The contaminated waters tend to be gathered close to the subsurface dams and this tendency did not differ between two subsurface dam settings, Komesu and Giza. However, due to more impact from manure storage sites, the groundwater in the Komesu area tends to show slightly higher δ15N NO3 values than those in the Giza area. Our study demonstrated the usefulness of soil samples for precise isotopic source identification in farmland areas. [ABSTRACT FROM AUTHOR]

We have previously cloned three distinct isoforms of group IB phospholipase A2 (PLA2), hepatopancreas DE-1 and DE-2 PLA2 and gill G-3 PLA2, from the red sea bream Chrysophrys major and found that they are expressed in a tissue-specific manner in the red sea bream. To understand the function of three group IB PLA2 isoforms, we constructed a bacterial expression system for DE-1, DE-2 and G-3 PLA2. The cDNAs encoding for mature PLA2 were amplified by polymerase chain reaction (PCR) and subcloned in-frame with a glutathione S-transferase (GST) encoded by the vector pGEX-4T-1. The resulting plasmids were used to transform Escherichia coli BL21 (DE3) cells. Three recombinant PLA2 were expressed as a fusion protein with GST in E. coli cells by induction of Isopropyl-1-thio-β-D-galactopyranoside. The bacterial cells were lyzed with strong alkaline solution and the fusion proteins were recovered as a soluble form. The fusion proteins were purified with affinity chromatography and cleaved by trypsin. Then, the recombinant DE-1 and G-3PLA2 were purified to near homogeneity by reversed-phase high-performance liquid chromatography (HPLC), and the recombinant DE-2 PLA2 by ion exchange chromatography and reversed-phase HPLC. Enzyme properties of purified recombinant DE-1, DE-2 and G-3 PLA2 were found to be essentially the same as those of native PLA2. [ABSTRACT FROM AUTHOR]