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Magnesium concentrations in acid‐sulfate fluids from Brothers and Macauley volcano, Kermadec arc, Western Pacific, exceed those of seawater and differ from previously known acid‐sulfate fluids with seawater‐like Mg concentrations. Earlier studies explained these Mg enrichments as due to phase separation, caminite (Mg1.25SO4(OH)0.5 × 0.5H2O) dissolution, water‐rock interaction and/or "mining" of deep seated magmatic brines. Since these different and partly contradictory explanations could neither be confirmed nor refuted, we investigated B, Li, and Mg isotope compositions in acid‐sulfate and black smoker fluids from both Brothers and Macauley to understand the origin of the high Mg concentrations and investigate a possible connection with the alteration of basement rocks. In addition, we performed seawater heating experiments to investigate Mg isotope fractionation during caminite precipitation. Lithium and B isotope signatures in all studied acid‐sulfate fluids indicate water‐rock interaction. Magnesium isotopes in fluids from Macauley correspond to seawater, implying Mg enrichment through phase separation in the fluids. In contrast, Mg‐enriched acid‐sulfate fluids from Brothers volcano have higher δ26Mg values (up to −0.62‰) than seawater. Considering that our seawater heating experiment shows a preferential incorporation of 24Mg into caminite, caminite dissolution would lead to lower δ26Mg values and thus cannot solely account for the enriched Mg concentrations seen at Brothers. Additionally, we thus suppose leaching of Mg from the basement during the interaction of acidic fluids with a relatively unaltered basement. Key Points: Mg isotopes in fluids from Macauley imply Mg enrichment by phase separationMg isotopes in fluids from Brothers indicate leaching of Mg from the basement24Mg is preferentially incorporated into caminite [ABSTRACT FROM AUTHOR]

We introduce a database of hydrothermal vent fluid compositions extracted from peer‐reviewed publications. The database includes general fluid parameters (e.g., temperature, salinity, and pH) as well as major‐, minor‐, and trace‐element concentrations (including rare earth elements) of dissolved cations, anions, reduced carbon compounds, and gases. In addition, isotopic compositions of elements and molecules are included. Each parameter in the database is given in a uniform unit and enables direct intercomparison of data from the incorporated sources. The database provides detailed information about geographic location, the date of sampling, and a broad set of supplementary information that enables clear identification of each individual sample and the original data source. This type of metadata was used to merge compositional data for discrete vent fluid samples that originate from different publications. Hence, the database provides a more complete set of compositional parameters than the original sources do. To facilitate operability, the database is provided as ®Excel sheet, which enables users to visualize, sort, filter, and evaluate the database in a straightforward way. The sample information metadata enables extraction of available vent fluid data for specific regions, tectonic settings, host rock types, etc. The database will be a useful tool in determining (1) mechanisms that set fluid chemistry, as well as (2) regional and global geochemical fluxes across the seabed. To demonstrate the extent of the database, we examine the global distribution of magnesium, chloride, and sodium concentrations in vent fluid samples that are incorporated in MARHYS Database. Plain Language Summary: We have compiled data for chemical compositions of hot solutions emitted from the ocean floor. This compilation uses data from journal publications, book chapters, and monographs and includes all chemical parameters that were found in the surveyed sources. The individual format in which the data are presented in the original sources varies considerably, which makes intercomparisons challenging. We have put all data in a common format to simplify the comparison of vent fluids from different sources. The sample information that was acquired along with the chemical data was used to find discrete samples that were analyzed in several publications and to merge the chemical data to unique entries. These merged entries provide a more complete chemical description of the samples than the original sources do. The database is included in an ®Excel sheet to provide interdisciplinary researchers a simple way to access, filter, and evaluate data. MARHYS Database provides an excellent mean to compare existing data with own results and provides a chance to evaluate globally or regionally averaged chemical compositions of hydrothermal solutions. To demonstrate the extent of the database, we present the distribution of magnesium, chloride and sodium concentrations of all samples incorporated in the database. Key Points: MARHYS Database: A comprehensive dataset of marine hydrothermal vent fluid compositions was compiledAverage values for hydrothermal fluids, end members, and seawater compositions are presentedThe database provides a mean to assess sample information and compositions for individual vents and regional/global compilations [ABSTRACT FROM AUTHOR]

The northwestern caldera wall of Brothers volcano in the southern Kermadec arc features several clusters of hydrothermal venting in a large area that extends from near the caldera floor (~1700 mbsl) almost up to the crater rim (~1300 mbsl). Abundant black smoker-type hydrothermal chimneys and exposed stockwork mineralization in this area provide an excellent archive of hydrothermal processes that form seafloor massive sulfide deposits. Using sulfate precipitates from chimneys and stockwork recently recovered by remotely operated vehicles, we conducted fluid inclusion microthermometry and Sr isotope studies to determine the role of phase separation and mixing between vent fluid and seawater. The variability in the vast majority of fluid inclusion salinities (i.e., 0.1–5.25 wt.% NaCl eq.) and entrapment temperatures of up to 346°C are indicative of phase-separated hydrothermal fluids. Large salinity variations in samples with entrapment temperatures mostly below the boiling temperature for the sample's depth show that the majority of fluids ascending below the NW Caldera are phase separating in the subsurface and cooling, prior to discharge. In several samples, entrapment temperatures of over 343°C suggest that phase-separating fluids have at least sporadically exited the seafloor at the NW Caldera site. Isobaric-isenthalpic mixing trends between coexisting phase-separated vapors and brines with seawater are consistent with phase-separated fluids at near-seafloor pressures of ~170 bar and suggest that the vast majority of the ascending fluids continue to phase separate to within tens to hundreds of meters below seafloor prior to mixing with seawater. A small subset of the most saline fluid inclusions (up to 18.6 wt.% NaCl eq.) is unlikely formed by near-seafloor phase separation and is considered to be produced either by supercritical phase separation or by the contribution of a magmatic brine from near the magmatic-hydrothermal interface. 87Sr/86Sr values of sulfate samples range from 0.7049 (i.e., near hydrothermal end-member) to 0.7090 (i.e., near seawater) and show that the crystals grew from vapor- and brine-derived fluids in a hydrothermally dominated mixing regime. Our work provides new insights into mineral growth conditions, mixing regimes, and in particular, the extent and character of subseafloor phase separation during the formation of hydrothermal vents and their underlying stockwork in seawater-dominated, arc-related hydrothermal systems. [ABSTRACT FROM AUTHOR]

The Gene Ontology (GO) is widely recognized as the premier tool for the organization and functional annotation of molecular aspects of cellular systems. However, for many immunologists the use of GO is a very foreign concept. Indeed, as a controlled vocabulary, GO can almost be considered a new language, and it can be difficult to appreciate the use and value of this approach for understanding the immune system. This review reflects on the application of GO to the field of immunology and explains the process of GO annotation. Finally, this review hopes to inspire immunologists to invest time and energy in improving both the content of the GO and the quality of GO annotations associated with genes of immunological interest. [ABSTRACT FROM AUTHOR]

Naltrexone is an opiate receptor antagonist mainly at the µ-receptor that is thought to reduce the positively reinforcing, pleasurable effects of alcohol and to reduce craving. An increase in time to first relapse to heavy drinking has been the most consistent finding obtained with naltrexone, although not all trials including two of the largest have been positive. Inconsistent outcome data suggest that effectiveness varies among different subgroups of patients. This paper re-evaluates recent data on the effectiveness of naltrexone in subjects differentiated according to Cloninger Type I and II. Moreover, it combines and cross-validates results of two recent European studies that found naltrexone treatment more beneficial in alcohol-dependent patients with early age at onset of drinking problems (Cloninger Type II). It is discussed whether especially these subjects should be targeted for pharmacological relapse prevention treatment with naltrexone. [ABSTRACT FROM AUTHOR]

Objectives: This pilot study has been designed to collect preliminary data on the use of a new antiepileptic drug in the management of alcoholic patients. Oxcarbazepine (OXC) blocks voltage-sensitive sodium channels. Its metabolite reduces high-voltage–activated calcium currents in striatal and cortical neurons, thus reducing glutamatergic transmission at corticostriatal synapses. This reduction is of interest in the treatment of alcohol dependence, as acamprosate (ACP) modulates NMDA receptors, resulting in an inhibition of glutamatergic transmission. Furthermore, OXC has revealed a mood-stabilizing effect in bipolar affective disorders. We have compared OXC with ACP in relapse prevention in recently withdrawn alcohol-dependent patients. Methods: We investigated the efficacy and safety of OXC (vs ACP) by conducting a 24-week randomized, parallel-group, open-label, clinical trial on 30 acutely detoxified alcoholic patients. Survival analyses (Kaplan–Meier) were performed to look for evidence of a longer “survival” of patients receiving OXC. We assessed time to first severe relapse and additional secondary endpoints. Results: After withdrawal, time to severe relapse and time to first consumption of any ethanol by OXC patients were not longer than for ACP patients. Abstinent patients in both study groups showed a significantly lower obsessive compulsive drinking scale—German version (OCDS-G) than relapsed patients. No undesired effects occurred when OXC patients consumed alcohol. Conclusion: Our findings indicate that it could be worthwhile to test relapse prevention using OXC in an adequate sample. While the current sample size clearly limits further conclusions from this pilot study, it is noteworthy that OXC is well tolerated, even when alcohol is on board. Thus, in medication-based relapse prevention, OXC could be a promising alternative for alcoholic patients unable to benefit from ACP or naltrexone or those who have affective liability. OXC certainly merits a larger placebo-controlled trial. [ABSTRACT FROM AUTHOR]

Background The nicotinic acetylcholine receptor partial agonist varenicline has been shown to be effective in the treatment of tobacco dependence, but has been reported to induce exacerbations of psychiatric symptoms in subjects with pre-existing psychiatric disorders. Case description We report a tobacco-dependent patient who developed depression and suicidal tendencies during several cessation attempts, but was finally able to stay nicotine-abstinent by taking varenicline. Conclusion In this case varenicline did not lead to exacerbation but appeared to improve the affective symptoms. [ABSTRACT FROM AUTHOR]