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The physical properties of seafloor massive sulfides are crucial for interpreting sub-seafloor images from geophysical surveys, shedding light on the evolution of seafloor mineral deposits. While some studies have explored the relationship between electrical properties and the volume of conductive minerals in rocks from seafloor massive sulfide deposits, they primarily focused on artificial samples, leaving the characteristics of natural samples less understood. Moreover, there has been no comprehensive study detailing the general characteristics of electrical properties, particularly chargeability and relaxation time, in relation to the volumetric fraction of sulfides in rocks from massive sulfide mounds in typical hydrothermal areas. In this study, we employed complex conductivity measurements, elemental concentration analysis, and mineral content identification on to rock samples from the active hydrothermal zones of the Okinawa Trough in Japan. The complex conductivity observed was remarkably high, with a pronounced imaginary component and a broad frequency range. This is attributed to induced polarization extending beyond our measurement range. The rock samples were rich in conductive sulfide minerals such as pyrite, chalcopyrite, and galena. Using the Cole–Cole rock physics model, we established a correlation between rock chargeability and relaxation time coefficient with the volume fraction of conductive sulfide minerals, which deviated from previous findings. The intensity of induced polarization was notably higher than anticipated in earlier studies using artificial samples. Furthermore, we observed a distinct positive correlation between the coefficient of relaxation time and the increase in sulfide volume, likely due to the geometric characteristics of the sulfide minerals. Our findings suggest that rocks in massive sulfide mounds may generally construct sulfide clusters that lengthen the conductive path of the electrical carrier. [ABSTRACT FROM AUTHOR]

As a passive technology, constructed wetlands (CWs) are promising candidates for mine-drainage treatment. However, the design and operation of CWs have not been fully established because the chemical compositions of mine drainage are diverse. In this study data sets of 100 mine drainages in Japan were classified using multivariate analysis based on water quality. Mine drainage was classified into eight types based on the ratio of the concentrations of Cd, Pb, As, Cu, Zn, Fe, and Mn to the effluent standard: (I) neutral and low metal concentration, (II) weakly acidic and low metal concentration, (III) weakly acidic and high Zn concentration, (IV) weakly acidic and high Mn and Zn concentrations, (V) acidic and high As concentration, (VI) acidic and high Fe concentration, (VII) acidic and extremely high Fe concentration, and (VIII) acidic and high Zn concentration. Mechanisms for removing metals in CWs were discussed based on this classification. Metal hydroxides of Cu, Pb, Zn, and Cd can precipitate with an increasing pH. Under oxidative conditions, dissolved Fe and Mn are oxidized to metal oxides. Under reductive conditions, Pb, Zn, Cd, and Cu precipitate as metal sulfides. This classification of mine drainage will be helpful in the systematic design and operation of CWs. [ABSTRACT FROM AUTHOR]

The Hokuroku region of north-eastern Japan is endowed with important volcanic-hosted massive sulphide Zn–Pb–Cu deposits, which are considered the archetype of Kuroko (black ore) deposits worldwide. The bimodal, felsic-dominated volcanic succession that hosts the ore was deposited in a continental rift formed during continental extension in the final stages of the Miocene back-arc opening that led to the formation of the Japan Sea. In this study, we define some of the fundamental intensive parameters of this volcanism (temperature, pressure of crystallisation, fluid saturation, fO2) based on rock textures, and analyses of whole-rock samples, minerals and melt inclusions. Based on the melt inclusion analyses, we assess the behaviour of metals during magma evolution and degassing, and evaluate the possible implications for ore deposition. Plagioclase-melt geothermometry in felsic tuff and lava samples collected from both the units underlying and overlying the Kuroko indicates temperatures of 880–940 °C, and Fe–Ti oxide equilibrium indicates oxygen fugacity of ca. FMQ + 1.5. Melt inclusions have high-SiO2 rhyolite compositions (> 75 wt%, on an anhydrous basis), and the plot of normative mineral compositions in the granitic triplot indicates low pressure of magma stalling and crystallisation (< 1 kbar) at cotectic compositions. Melt inclusion metal contents plotted vs incompatible element Y suggest contrasting behaviour of different metals during fractionation and degassing. Zinc was mostly retained in the melt during crystallisation, whereas other metals, such as Pb, Cu, Sn and Mo, were released to an exsolving fluid phase. The latter may have thus been transferred to the hydrothermal system from a degassing magma. Shallow storage of relatively hot magma would have induced vigorous hydrothermal circulation on the seafloor, a precondition for ore deposition. [ABSTRACT FROM AUTHOR]

Blooms of green macroalgae (Ulva spp.) occur frequently in the hypereutrophic Yatsu tidal flat of eastern Japan. In this study, to elucidate the effects of such blooms on nutrients and sulfide dynamics, we measured Ulva nutrients uptakes and stocks, and sulfide release during Ulva blooms decay. NH4+ uptake was greater than NO3– uptake when NH4+ was sufficient, whereas NO3– uptake increased in the absence of NH4+. NH4+ concentration was generally higher than that of NO3– in seawater; thus, Ulva spp. would prefer NH4+ as N substrate. The mean N and P amounts in Ulva blooms were 2,320 kg-N and 116 kg-P, respectively. Sudden, rapid blooms collapse appears to release extremely high amounts of nutrients, especially NH4+. Thus, Ulva blooms affect NH4+ behavior and consequently affect N cycling in the Yatsu tidal flat. High sulfide concentrations were detected under anoxic Ulva mats following peaks in biomass. Incubation experiments revealed that sulfide was derived not only from SO42– in seawater but also from the S contained in Ulva spp. Subsequently, sulfide might be microbiologically oxidized to elemental sulfur thereafter. Moreover, sulfide was not detected without Ulva spp.. Therefore, Ulva blooms also influence S cycling in Yatsu tidal flat. [ABSTRACT FROM AUTHOR]

• Fe isotopes were variable in ferruginous rocks during and after Kuroko formation. • Anoxic pools in Hokuroku Basin may have facilitated preservation of sulfide ores. • Prominent Eu anomalies in ferruginous rocks indicate association with VMS deposits. • Fe isotopes in Zn-rich black ores are negatively shifted due to a kinetic effect. • Duration of hydrothermal circulation is a primary control on ore grade and tonnage. Anoxic seawater may have played an important role in the preservation of volcanogenic massive sulfide (VMS) deposits in the Hokuroku district, northeast Japan, which is the type locality for Kuroko-type VMS deposits. In this study, we investigated the Fe isotopic compositions of sulfide ores and overlying ferruginous sedimentary rocks in these deposits. These data, coupled with petrographic and geochemical data, enable us to investigate the key formation processes and conditions during the formation of large Kuroko-type VMS deposits. Large Fe isotope variations of ca. 4‰ (δ56Fe) associated with negative or positive Ce anomalies characterize the ferruginous sedimentary rocks formed in the Kuroko VMS deposits and post-Kuroko hydrothermal activity. This suggests that iron (hydr)oxides were precipitated by the partial oxidation of dissolved Fe2+ derived from hydrothermal fluids in anoxic or suboxic pools in the Hokuroku Basin. Positive Eu anomalies in the ferruginous cherts closely associated with the Kuroko VMS deposits indicate formation from high-temperature hydrothermal fluids. Zinc-rich black ores in both the Matsumine and Fukazawa deposits have lower δ56Fe values, due to rapid precipitation of pyrite triggered by the mixing of hydrothermal fluids with seawater. Positive shifts in δ56Fe values in the ferruginous cherts from the Ezuri and Fukazawa deposits may be explained by simultaneous precipitation of ferruginous sedimentary rocks with black ores, which modified the δ56Fe values of the hydrothermal fluids to positive values. However, Cu-rich yellow ores show no significant Fe isotope fractionation as compared with the dissolved Fe in the hydrothermal fluids, and were likely formed by slow growth of pyrite that replaced the black ores. The difference in the abundance of sulfide ores between the Matsumine and Fukazawa deposits may reflect the duration of hydrothermal circulation. [ABSTRACT FROM AUTHOR]

Abstract: The southwestern Hokkaido mining district is well known for the occurrence of many epithermal ore deposits ofNeogene Tertiary period.The ore mineral assemblages in the epithermal gold-silver deposits from the southwestern Hokkaido such as Kobetsuzawa, Shin Otoyo, Suttsu, Chitose, Teine, Date, Koryu and Toya mines are examined. The determinations of their minerals assemblages are based on the study of samples collected during field works in the southwestern Hokkaido and from the Hokkaido University Museum collection. Combinations of microscopic, electron-microprobe, and BSE-based image analyses of polished sections were used to evaluate the chemical composition of ore minerals. Most of gold-silver in the magmatic-hydrothermal systems of the southwestern Hokkaido are enriched in tellurides and Te-bearing minerals, suggesting major carriers of precious metal in the ore. Other minerals are sulfides, sulfosalts and oxides group of ores, although each deposit is characterized by the occurrence of some difference ore minerals assemblages. The presences ofenargite or famatinite in some deposits suggest the deposition in the higher sulfidation state of epithermal mineralization style. The measurement ofhomogenization temperature and salinity of fluid inclusions in some gangue minerals such as quartz associated with ores from those deposits suggest that the formation temperature in general are around 170 — 260°Cwith salinity less than 4wt.% NaClequiv.Boiling indications in fluid inclusions of some deposits give the possibility this phenomenainfluence to the ore precipitation. [Copyright &y& Elsevier]

For leukotriene receptor antagonists (LTRAs), especially pranlukast, safety data during pregnancy is limited. Therefore, we conducted a prospective, two-centered cohort study using data from teratogen information services in Japan to clarify the effects of LTRA exposure during pregnancy on maternal and fetal outcomes. Pregnant women who being counseled on drug use during pregnancy at two facilities were enrolled. The primary outcome of this study was major congenital anomalies. The incidence of major congenital anomalies in women exposed to montelukast or pranlukast during the first trimester of pregnancy was compared with that of controls. Logistic regression analysis was performed to analyze the effects of maternal LTRA use during the first trimester of pregnancy on major congenital anomalies. The outcomes of 231 pregnant women exposed to LTRAs (montelukast n = 122; pranlukast n = 106; both n = 3) and 212 live births were compared with those of controls. The rate of major congenital anomalies in the LTRA group was 1.9%. Multivariable logistic regression analysis revealed that LTRA exposure was not a risk factor for major congenital anomalies (adjusted odds ratio, 0.78; 95% confidence interval, 0.23-2.05; p = 0.653). In addition, no significant difference was detected in stillbirth, spontaneous abortion, preterm birth, and low birth weight between the two groups. The present study revealed that montelukast and pranlukast were not associated with the risk of major congenital anomalies. Our findings suggest that LTRAs could be safely employed for asthma therapy during pregnancy., (© 2022 Japanese Teratology Society.)

Various invertebrates inhabiting hydrothermal vents harbor thiotrophic endosymbionts that provide the host with nutrients and are possibly involved in the detoxification of harmful sulfides. In this study, we first determined the partial 16S rRNA gene sequence of the thiotrophic symbiont of the deep-sea mussel Bathymodiolus septemdierum, a dominant species at hydrothermal vents in the Izu-Ogasawara (Bonin) area. We then designed a new probe, Bsob692, for fluorescent in situ hybridization (FISH) using regions completely conserved among thiotrophic symbionts of all bathymodiolin mussels and established the protocol for FISH to compare the distribution and amount of the symbiont using an image analysis program that is commercially available. We compared fluorescent intensity in the gill of the mussels collected at different sites and found a higher intensity in specimens collected from a site with higher sulfide concentration. We also compared mussels reared in the presence and absence of sulfide and found that the former had a higher fluorescent intensity. [ABSTRACT FROM AUTHOR]

Atmospheric carbonyl sulfide (COS) mixing ratios measured over 24 h during five summer campaigns (2003-2007) in a forest at the foot of Mt. Fuji, Japan (35°21′ N, 138°43′ E; 1,300 m above sea level, a.s.l.) and at the summit (3,776 m a.s.l.) were compared. COS levels were lower at the foot than at the summit during four out of five summer campaigns. The ratios of COS mixing ratios at the foot of Mt. Fuji to those at the summit ranged from 0.7 to 0.9. These results provide evidence of biological consumption of COS in the East Asian atmospheric boundary layer. We also measured the vertical profile of ambient COS below the forest canopy. These data showed a clear gradient of COS mixing ratio: in the lowermost 1 m of the boundary layer, COS mixing ratios decreased markedly downward. Two of the different kinds of vertical distribution of COS presented here support the role of soil as a sink of atmospheric COS described by previous research using dynamic enclosure experiments. [ABSTRACT FROM AUTHOR]

Spatial patterns and morphology of hydrothermal vents and the occurrence of vent-associated megafauna were investigated in the back-arc basin system of the Okinawa Trough, western Pacific. Amongst hydrothermal vent fields located on the rising slopes to the NE and S of the basin, the Iheya North area has been subjected to a series of intensive diving surveys. Hydrothermal vents demonstrated concentrated patterns of distribution on different spatial scales. In Iheya North, the majority of vents occurred in lines parallel to the NE to W/SW alignment of the spreading axis, within a radius of ca. 200 m around the most active sulphide structure with the highest recorded fluid temperature of over 300°C. The morphology of hydrothermal vents varied greatly from an incipient flat rock with crevices to a 20- to 30-m-tall, multi-flanged structure with concomitant variation in the distribution and abundance of vent-associated megafauna, particularly a galatheid Shinkaia crosnieri and Bathymodiolus mussels. Comparison of active and inactive vents revealed that the spatial extent of Shinkaia 'aggregation' (a group of individuals with short nearest-neighbour distances) effectively defined a habitat unit of this species, and active hydrothermal chimneys contained more of these units, leading to greater spatial occupancy by Shinkaia. Given the temporally unstable nature of vent structures as recognised by repeated surveys, vent assemblages are thought to be closely dictated by the spatio-temporal dynamics of vents in the Okinawa Trough back-arc system. [ABSTRACT FROM AUTHOR]

The northeast (NE) Honshu arc was formed by three major volcano-tectonic events resulting from Late Cenozoic orogenic movement: continental margin volcanism (before 21 Ma), seafloor basaltic lava flows and subsequent bimodal volcanism accompanied by back-arc rifting (21 to 14 Ma), and felsic volcanism related to island arc uplift (12 to 2 Ma). Eight petrotectonic domains, parallel to the NE Honshu arc, were formed as a result of the eastward migration of volcanic activity with time. Major Kuroko volcanogenic massive sulfide (VMS) deposits are located within the eastern marginal rift zone (Kuroko rift) that formed in the final period of back-arc rifting (16 to 14 Ma). Volcanic activity in the NE Honshu arc is divided into six volcanic stages. The eruption volumes of volcanic rocks have gradually decreased from 4,600 km (per 1 my for a 200-km-long section along the arc) of basaltic lava flows in the back-arc spreading stage to 1,000-2,000 km of bimodal hyaloclastites in the back-arc rift stage, and about 200 km of felsic pumice eruptions in the island arc stage. The Kuroko VMS deposits were formed at the time of abrupt decrease in the eruption volume and change in the mode of occurrence of the volcanic rocks during the final period of back-arc rifting. In the area of the Kuroko rift, felsic volcanism changed from aphyric or weakly plagioclase phyric (before 14 Ma), to quartz and plagioclase phyric with minor clinopyroxene (12 to 8 Ma), to hornblende phyric (after 8 Ma), and hornblende and biotite phyric (after 4 Ma). The Kuroko VMS deposits are closely related to the aphyric rhyolitic activity before 14 Ma. The rhyolite was generated at a relatively high temperature from a highly differentiated part of felsic magma seated at a relatively great depth and contains higher Nb, Ce, and Y contents than the post-Kuroko felsic volcanism. The Kuroko VMS deposits were formed within a specific tectonic setting, at a specific period, and associated with a particular volcanism of the arc evolution process. Therefore, detailed study of the evolutional process from rift opening to island arc tectonics is very important for the exploration of Kuroko-type VMS deposits. [ABSTRACT FROM AUTHOR]

The copper isotope ratios of chalcopyrite, secondary malachite, and native copper of metamorphosed Besshi-type volcanogenic massive sulfide (VMS) deposits from two different mines, Japan, were measured by femtosecond-pulsed laser ablation-multiple collector-inductively coupled plasma-mass spectrometry (fs-LA-MC-ICP-MS). The δ65Cu (where δ65 = [{(65Cu/63Cu)sample(65Cu/NIST-SRM679} - 1] x 1,000) values of chalcopyrite samples of both mines are relatively narrow (-0.34 to +0.29‰) compared to those of previously reported chalcopyrite from modern submarine hydrothermal deposits at mid-oceanic ridge settings (-0.98 to +3.14‰). However, the δ65Cu values of chalcopyrite are slightly different between the two mines. This suggests that, although metamorphic reequilibration may have reduced the original range of copper isotopes, premetamorphic δ65Cu characteristics of both mines are generally preserved. The chalcopyrite samples of one deposit might be significantly affected by dissolution during reworking processes after precipitation on the sea floor. Secondary malachite (δ65Cu = 2.63-2.97‰ and native copper (δ65Cu = 1.43-1.71‰) have higher δ65Cu values than chalcopyrite from the same deposit. This variation is most reasonably explained in terms of a redox-controlled isotope fractionation at low-temperature conditions during secondary (weathering) processes involving the preferential incorporation of 65Cu in secondary Cu(II) solutions. It is also suggested that significant negative isotopic fractionations accompanying the reduction of Cu (II) solutions to native copper [Cu (0)] occurred. [ABSTRACT FROM AUTHOR]

The article discusses a study regarding the chemical characteristics of the rotting-animal like odor being emitted by the flowering plant Titan Arum (Amorphophallus titanum). The study used gas chromatography-mass spectrometry olfactometry (GC-MS-O) to analyzed the volatile compounds taken from the inflorescence of a titan arum at the Botanical Gardens of the University of Tokyo in Japan. Results show that dimethyl trisulfide is the main odorant which causes the odor at the flowering stage.

The Fukusen No. 1 vein is located in the southeastern part of the Yamada deposit, Hishikari epithermal gold deposits, southern Kyushu, Japan. Ar/Ar plateau ages of adularia from the margin and the center of the Fukusen vein are determined to be 0.617 ± 0.024 Ma and 0.606 ± 0.009 Ma, respectively. The Fukusen No. 1 vein shows banding structure composed mainly of quartz, adularia and clay minerals. Colloform texture is displayed by cryptocrystalline to amorphous silica material that is associated with fine-grained electrum and sulfides near the center of the vein. Pyrite in the Fukusen No. 1 vein often shows acicular shape resulting from inversion from marcasite. Near the center of the vein, primary marcasite occurs associated with colloform texture of silica. The Fukusen No.1 vein preserves primary texture and materials which were deposited from the ore-forming hydrothermal solution. The Fukusen No. 1 vein was formed in a short period and is one of the youngest veins in the Hishikari deposits. [ABSTRACT FROM AUTHOR]

Abstract: Besshi-type Cu deposits are strata-bound volcanogenic massive sulfide deposits usually associated with mafic volcanic rocks or their metamorphic equivalents. Although there are numerous Besshi-type deposits in the Sanbagawa metamorphic belt, Japan, their tectonic settings and depositional environments remain controversial because of a lack of depositional age constraints. We report Re–Os data for the Iimori deposit, one of the largest Besshi-type deposits in western Kii Peninsula, in order to examine the robustness of the Re–Os isotope system for dating sulfide minerals in the high-P/T metamorphic belt and to elucidate the primary depositional environment of the Iimori sulfide ores. An 11-point Re–Os isochron plot yields an age of 156.8±3.6Ma. As this Re–Os isochron age is significantly older than the timing of the Sanbagawa peak metamorphism (110–120 or ∼90Ma) and a well-defined isochron was obtained, the Re–Os age determined here is most likely the primary depositional age. Despite high-grade metamorphism at up to 520±25°C and 8–9.5kbar, the Re–Os isotope system of the Iimori sulfides was not disturbed. Hence, we consider that the whole-rock Re–Os closure temperature for the Iimori sulfide ores was probably higher than 500°C. As the accretion age of the Sanbagawa metamorphic belt is considered to be 120–130 or 65–90Ma on the basis of radiolarian and radiometric ages, we estimated the time from the Iimori sulfide deposition on the paleo-seafloor to its accretion at the convergent plate boundary to be greater than 25Myr. Consequently, the depositional environment of the Iimori sulfide ores was not in the marginal sea, but was truly pelagic. [Copyright &y& Elsevier]

Noble gas compositions of fluid inclusions hosted in sulfides from two modern submarine hydrothermal sites of contrasting tectonic settings have been analyzed. The JADE Field (central Okinawa Trough, Japan) is located in an active intracontinental back-arc basin whereas the SO 134 field is related to the central spreading ridge of the North Fiji Basin, which represents an active, highly mature intra-ocean back-arc system. Previous conventional studies of fluid inclusions have revealed compelling evidence for subcritical phase separation of the hydrothermal fluids at both sites. Elemental abundances of Ne, Ar, Kr, and Xe in fluid inclusions in all studied samples of chalcopyrite and sphalerite from both hydrothermal sites indicate that the heavier noble gases are derived from ambient seawater. In contrast, helium concentrations are 1 to 2 orders of magnitude higher than expected for equilibrium solution in seawater, indicating that helium is predominantly derived from a magmatic source beneath the hydrothermal systems. The ³He/4He ratios in sphalerite-bested fluid inclusions from the JADE Field and the SO 134 field are similar to those reported from related vent fluids and show that fluid inclusions reliably record the helium isotope ratio of the original hydrothermal fluid. However, in the North Fiji Basin, earlier "black smoker" activity and the formation of Fe-rich "Kies-type" sulfides seems to have been related to a more MORB-like volcanism, whereas the younger recent "white smoker" hydrothermal activity in the North Fiji Basin can be attributed to a hot spot magmatism in the study area. [ABSTRACT FROM AUTHOR]

Volcanic-hosted, massive sulfide deposits of Zn-Pb-Cu type were derived either from seawater-dominated, buoyant fluids that built mounds on the seafloor, e.g., the ores of the Hokuroku Basin, Japan, or from saline fluids that reversed buoyancy on mixing with seawater and filled basins on the seafloor, e.g., several ores of the Iberian pyrite belt and the Mount Read province in Tasmania. The Hokuroku ores formed above subduction zones during protracted periods of regional extension, but both the Iberian pyrite belt and the Mount Read province formed under extensional stress during continent-continent (Iberia) or arc-continent (Mount Read) collision and orogenesis. In the Iberian pyrite belt oblique convergence resulted in transcurrent faulting, and this may also be the case for the Mount Read province. Transcurrent faulting may have allowed easy vertical access for the ore-related magmas, some of which were sourced in the asthenosphere, as well as the blueschist and eclogitic facies emplaced in adjacent terrains, and possibly also saline fluids exsolved from the magmas. [ABSTRACT FROM AUTHOR]

Exploration for volcanogenic massive sulfide deposits of the kuroko-type is underway in many places. Clarifying the spatial patterns of the metals in kuroko deposits will be useful for understanding their genetic mechanisms and for future exploration of such types of deposits. This study represents a spatial distribution analysis on the contents of principal metals of kuroko deposits: Cu, Pb, and Zn, in the Hokuroku district, northern Japan, by a feedforward neural network and 1917 sample data at 143 drillhole sites. The network, which consists of three layers, was trained by the principle of SLANS in which the numbers of neurons in the middle layer and training data are changed to improve estimation accuracy. Using the weight coefficients connecting adjacent neurons, sensitivity analysis of the neural network was carried out to identify factors influencing spatial distributions of the three metals. The coordinates depth (z) direction, Bouguer gravity, and specific lithology such as dacite were determined to be influencing factors. The high frequency of the z coordinate signifies that the metal contents differ to a large extent by depth. The sensitivity vector was defined using sensitivity coefficients for x, y, and z coordinates of an estimation point. We determined that the directions of large vectors were different inside and outside of the Hanawa-Ohdate area. This characteristic is considered to originate from the differences in the permeability of fractures that became the paths for rising ore solutions, and the depths that the solutions mixed with sea water. KEY WORDS: Kuroko; metal content; feedforward neural network; sensitivity analysis; influence factor; sensitivity vector. [ABSTRACT FROM AUTHOR]

• Greenstone samples associated with Besshi-type ores show N-MORB and E-MORB features. • Trace element variations in pyrite are mostly influenced by inclusions of sphalerite and chalcopyrite. • The δ34S values of pyrites from Besshi suggest origin from high temperature hydrothermal fluids. • The Re-Os isotope geochronology of pyrite constraints timing of sulfide deposition at 147.9 Ma. • Ore formation was in a pelagic setting, associated with mid ocean ridge volcanism. The Besshi Cu-rich volcanogenic massive sulfide (VMS) deposit occurring in the type area of Besshi, central Shikoku, Southwest Japan comprises tabular orebodies closely associated with mafic schist in the Cretaceous Sambagawa high P/T metamorphic belt. Pyrite, chalcopyrite, and sphalerite are the dominant sulfide minerals, together with minor amounts of pyrrhotite and bornite. The associated greenstone samples show geochemical features between N-MORB and E-MORB. The δ34S values of sulfides from the greenstones and Cu ores are in the range of 2.10 to 7.11‰, indicating deposition from hydrothermal fluids with a heterogeneous metal source. Re-Os analysis of sulfides show initial (187Os/188Os) i ratio of 1.14 ± 0.86 and yield an isochron age of 147.9 ± 4.2 Ma, considered as the timing of sulfide deposition on the paleo-seafloor. The lithological association, geochemical features of the host greenstones and isotopic data from the sulfides indicate that the Besshi-type ores formed in a pelagic setting, and are possibly associated with hydrothermal activity related to mid ocean ridge volcanism and can be correlated to a major oceanic anoxic event. [ABSTRACT FROM AUTHOR]

A novel thermophilic phototrophic purple sulphur bacterium was isolated from microbial mats (56 °C) at Nakabusa hot springs, Nagano prefecture, Japan. Cells were motile, rod-shaped, stain Gram-negative and stored sulphur globules intracellularly. Bacteriochlorophyll a and carotenoids of the normal spirilloxanthin series were the major pigments. Dense liquid cultures were red in colour. Strain No.7 T was able to grow photoautotrophically using sulfide, thiosulfate, sulfite and hydrogen (in the presence of sulfide) as electron donors and bicarbonate as the sole carbon source. Optimum growth occurred under anaerobic conditions in the light at 50 °C (range, 40-56 °C) and pH 7.2 (range, pH 7-8). Major fatty acids were C 16 : 0 (46.8 %), C 16 : 1  ω7 c (19.9 %), C 18 : 1  ω7 c (21.1 %), C 14 : 0 (4.6 %) and C 18 : 0 (2.4 %). The polar lipid profile showed phosphatidylglycerol and unidentified aminophospholipids to be the major lipids. The only quinone detected was ubiquinone-8. 16S rRNA gene sequence comparisons indicated that the novel bacterium is only distantly related to Thermochromatium tepidum with a nucleotide identity of 90.4 %. The phylogenetic analysis supported the high novelty of strain No.7 T with a long-branching phylogenetic position within the Chromatiaceae next to Thermochromatium tepidum . The genome comprised a circular chromosome of 2.99 Mbp (2 989 870 bp), included no plasmids and had a DNA G+C content of 61.2 mol%. Polyphasic taxonomic analyses of the isolate suggested strain No.7 T is a novel genus within the Chromatiaceae . The proposed genus name of the second truly thermophilic purple sulphur bacterium is Caldichromatium gen. nov. with the type species Caldichromatium japonicum sp. nov. (DSM 110881=JCM 39101).

The effects of increased mining of seafloor massive sulfide deposits on marine ecosystems have not been characterized. In this study, the impact of leaching metals from a hydrothermal sulfide on photosynthetic protist and cyanobacterial communities in marine environments was investigated by amplicon analyses of small subunit rDNA (SSU rDNA) and rRNA (SSU rRNA). Seawater samples collected from the Iheya North region and Suruga Bay, Japan, were incubated with or without a leachate containing zinc, copper, cadmium, and manganese, of the actual seafloor hydrothermal sulfide from the Hakurei site in the Izena Hole region. The relative abundances of prasinophytes, diatom protists, and the cyanobacteria Synechococcus decreased substantially during incubation with leachate, indicating the vulnerability of these lineages to the leachate. Phylogenetic analysis based on the cyanobacterial phycocyanin cpcBA/rpcBA operon obtained from samples incubated with or without leachate indicated that the individual lineages of Synechococcus can determine sensitivity to heavy metals in different marine regions as well as particular clades and ecotypes. [ABSTRACT FROM AUTHOR]

Background: While Japanese guideline recommends initial control treatment for preschool children with asthma symptoms more than once a month, Western guidelines do not. To determine whether control treatment with montelukast was more effective than as-needed β 2 -agonists in this population, we conducted a randomized controlled trial., Methods: Eligible patients were children aged 1-5 years who had asthma symptoms more than once a month but less than once a week. Patients were randomly assigned in a 1:1 ratio to receive montelukast 4 mg daily for 48 weeks or as-needed β 2 -agonists. The primary endpoint was the number of acute asthma exacerbations before starting step-up treatment with inhaled corticosteroids. This study is registered with the University Hospital Medical Information Network clinical trials registry, number UMIN000002219., Results: From September 2009 to November 2012, 93 patients (47 in the montelukast group and 46 in the no-controller group) were enrolled into the study. All patients were included in the analysis. During the study, 13 patients (28%) in the montelukast group and 23 patients (50%) in the no-controller group had acute exacerbations with the mean numbers of 0.9 and 1.9/year, respectively (P = 0.027). In addition, 10 (21%) and 19 (41%) patients received step-up treatment, respectively. Cumulative incidence of step-up treatment was significantly lower in the montelukast group (hazard ratio 0.45, 95% confidence interval 0.21 to 0.92; P = 0.033)., Conclusions: Montelukast is an effective control treatment for preschool children who had asthma symptoms more than once a month but less than once a week., (Copyright © 2017 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.)

Objective: Orally disintegrating tablets (ODTs) offer a valuable treatment option, particularly when swallowing solid tablets with water is difficult or inconvenient. Montelukast is an effective treatment for asthma and allergic rhinitis (AR), and an ODT formulation became available in Japan in 2015. This study investigated levels of satisfaction with this new formulation among adults with asthma and/or AR in Japan., Methods: Patients aged 20 years or older who were refilling a prescription for montelukast ODT in pharmacies across Japan completed questions on satisfaction with key features of montelukast ODT and the 9-item Treatment Satisfaction Questionnaire for Medication (TSQM-9). Study variables were analyzed descriptively. Factors associated with TSQM-9 global satisfaction and convenience domain scores were examined using analysis of covariance., Results: Of the 201 patients who participated, 89.6% reported overall satisfaction with montelukast ODT. Overall satisfaction was highest in patients with AR only (94.7% satisfied) or with asthma and AR (90.2% satisfied), and in patients with treatment duration <4 weeks (98.5% satisfied). Mean TSQM-9 global satisfaction and convenience domain scores were 58.9 and 66.7, respectively; scores were higher for patients with both asthma and AR and for those with longer disease duration. Overall ease of taking and dissolving speed were most closely associated with TSQM-9 global satisfaction scores, and ability to take without water and taste were most closely associated with TSQM-9 convenience scores., Limitations: The generalizability of the findings was limited by the convenience sample and the descriptive, single-arm study design. The study was limited to adults with asthma and/or AR., Conclusion: Montelukast ODT may be an acceptable dosage formulation for adults with mild-to-moderate asthma and/or AR in Japan. Satisfaction was high, particularly with respect to tablet size, dissolving speed, taste, and ease of taking.

What Is Known and Objective: Montelukast, a cysteinyl leukotriene receptor 1 antagonist, is safe and efficacious in patients with asthma. The mechanisms underlying the significant interpatient variability in response to montelukast are not clear but are believed to be, in part, because of genetic variability., Methods: To examine the associations between polymorphisms in candidate genes in the leukotriene pathway and outcomes in patients with asthma on montelukast for 4-8 weeks, we evaluated the changes in peak expiratory flow (PEF), forced expiratory volume in 1 s (FEV(1·0) ) and patients' subjective symptom before and after montelukast treatment. DNA was collected from 252 Japanese participants., Results and Discussion: Two single-nucleotide polymorphisms (SNPs) in the ALOX5 (rs2115819) and LTA4H (rs2660845) genes were successfully typed. There was no difference between members of the general population (n = 200) and patients (n = 52) in each genotype frequency. Significant associations were found between SNP genotypes in the LTA4H gene and changes in PEF and FEV(1·0) . The PEF and FEV(1·0) responses to montelukast in the A/A genotypes (n = 4) for the LTA4H SNP were significantly higher than those in the G allele carriers (A/G+G/G) (n = 17)., What Is New and Conclusion: Despite the small sample size, our results suggest that genetic variation in leukotriene pathway candidate genes contributes to variability in clinical responses to montelukast in Japanese patients with asthma., (© 2011 Blackwell Publishing Ltd.)

Sulfur-turf microbial mats develop in sulfide-containing hot spring water dominated by chemolithoautotrophic sulfur-oxidizing bacteria. The sulfur-turf mat that developed at a source of hot water (72°C, pH 6.8) exhibited a growth rate of 0.48±0.04 h(-1) and biomass production of 4.6±1.0 mg of C h(-1). On a per-cell basis, this biomass production was at least an order of magnitude higher than the CO(2) uptake rate calculated for a photosynthetic mat dominated by thermophilic Synechococcus spp. at 70°C. The sulfur-turf-associated microbial community likely contributes to carbon fixation and primary production in this geothermal habitat.

Background: Secretion of nasal discharge was enhanced and airway-resistance in the nasal cavity was augmented, resulting in nasal congestion, when leukotrienes were administered to the nasal mucosa. These results indicate that leukotrienes play an important role in the pathogenesis of allergic rhinitis., Methods: A double-blind clinical study was carried out to evaluate the efficacy and the safety of montelukast, a cysteinyl leukotriene receptor 1 antagonist, 5 mg, 10 mg or placebo orally administered once daily at bedtime for 2 weeks, to Japanese patients with seasonal allergic rhinitis. The composite nasal symptom scores (average over the 2-week treatment period) were compared among the montelukast 5 mg and 10 mg groups with the placebo group., Results: The composite nasal symptom score significantly improved in the montelukast 5 mg and 10 mg groups compared with the placebo group. The administration of montelukast 5 mg or 10 mg once daily was well tolerated and the safety profiles were similar to those of the placebo. There were no significant differences in the incidences of adverse experience or drug-related adverse experience among the montelukast 5 mg, 10 mg groups and the placebo group., Conclusions: Both montelukast 5 mg and 10 mg doses show clinically meaningful efficacy for the treatment of patients with seasonal allergic rhinitis and the safety profiles of those are comparable to that of the placebo.