Production of interleukin-10 by alveolar macrophages from lung cancer patients

AbstractInterleukin (IL)-10 is known to be an autoregulatory factor of functions of monocyte macrophages. The purpose of this study was to determine whether IL-10 production by alveolar macrophages (AMs) is altered in patients with lung cancer. AMs were obtained by bronchoalveolar lavage from 25 patients with lung cancer and 14 control patients. The production of IL-10 by AMs was quantitated by enzyme immunoassay with or without stimulation with lipopolysaccharide (LPS). No significant difference in spontaneous and LPS-stimulated IL-10 production by AMs was observed between lung cancer patients and control patients (mean ± sem; 288·0 ± 56·7 vs. 249·6 ± 58·4 pg ml−1). IL-10 production of LPS-stimulated AMs was not impaired even in lung cancer patients with systemic metastasis. IL-4 failed to suppress LPS-induced production of IL-10 by AMs both in control patients and in lung cancer patients. In eight patients with lung cancer, IL-10 production by AMs was estimated before and after systemic chemotherapy and IL-10 production by LPS-stimulated AMs tended to increase after systemic chemotherapy from 152·3 ± 51·9 to 278·0 ± 112·8 pg ml−1. As IL-10 is a potent inhibitor of tumour angiogenesis, an important process of tumour progression, these results suggest that, even in advanced cancer patients, macrophages can produce potent angiogenesis inhibitor and systemic chemotherapy may augment this inhibitory activity in the lung

Large sulfur isotope fractionations in Martian sediments at Gale crater

Variability in the sulfur isotopic composition in sediments can reflect atmospheric, geologic and biological processes. Evidence for ancient fluvio-lacustrine environments at Gale crater on Mars and a lack of efficient crustal recycling mechanisms on the planet suggests a surface environment that was once warm enough to allow the presence of liquid water, at least for discrete periods of time, and implies a greenhouse effect that may have been influenced by sulfur-bearing volcanic gases. Here we report in situ analyses of the sulfur isotopic compositions of SO2 volatilized from ten sediment samples acquired by NASA’s Curiosity rover along a 13 km traverse of Gale crater. We find large variations in sulfur isotopic composition that exceed those measured for Martian meteorites and show both depletion and enrichment in 34S. Measured values of δ34S range from −47 ± 14‰ to 28 ± 7‰, similar to the range typical of terrestrial environments. Although limited geochronological constraints on the stratigraphy traversed by Curiosity are available, we propose that the observed sulfur isotopic signatures at Gale crater can be explained by equilibrium fractionation between sulfate and sulfide in an impact-driven hydrothermal system and atmospheric processing of sulfur-bearing gases during transient warm periods

Three-Dimensional Spatially Constrained Sulfur Isotopes Highlight Processes Controlling Sulfur Cycling in the Near Surface of the Iheya North Hydrothermal System, Okinawa Trough

Abstract Modern seafloor hydrothermal systems are unique environments in which many of the Earth's reservoirs, including the hydrosphere, biosphere, and geosphere, dynamically interact. Analysis of spatially constrained sulfur isotope compositions from fluids and hydrothermal precipitates within the discharge zone of a volcanogenic system can be used to trace the interactions between the various isotopically distinct sulfur reservoirs that result in the formation of hydrothermal massive sulfide deposits. Here we present in situ sulfur isotope results from laterally and vertically constrained euhedral hydrothermal pyrite from the Iheya North hydrothermal system in the Okinawa Trough, which was investigated during the Integrated Ocean Drilling Program Expedition 331. Hydrothermal pyrite at the North Big Chimney yields δ34S values of ~+11.9 ± 1.1‰ (1σ), which are near identical to the δ34S composition of the vent fluid. Outward, ~150 and ~450 m from North Big Chimney, hydrothermal pyrite within drill core yields δ34S equal to +10.9 ± 1.3‰ (1σ) and +7.0 ± 3.8‰ (1σ), respectively, showing a shift in isotopic composition away from the main vent site. This evolution to a lighter and more scattered isotopic signature of hydrothermal pyrite (which is easily identifiable from biogenic pyrite) is interpreted to indicate that the hydrothermal fluid leached sulfides (formed previously by biogenic processes) from the surrounding sedimentary strata. As the most significant metal enrichments (Fe, Zn, Cu, Bi, Tl, and Cd) are associated with samples that contain average hydrothermal pyrite δ34S values similar to δ34S of the vent fluid, we demonstrate that sulfur isotopes can vector toward metals in seafloor massive sulfide deposits

An Archean Biosphere Initiative

The search for life on extrasolar planets will necessarily focus on the imprints of biolgy on the composition of planetary atmospheres. The most notable biological imprint on the modern terrestrial atmosphere is the presence of 21 % O2, However, during most of the past 4 billion years, life and the surface environments on Earth were profoundly different than they are today. It is therefore a major goal of the astrobiology community to ascertain how the O2 content of the atmosphere has varied with time. and to understand the causes of these variations. The NAI and NASA Exobiology program have played critical roles in developing our current understanding of the ancient Earth's atmosphere, supporting diverse observational, analytical, and computational research in geoscience, life science, and related fields. In the present incarnation of the NAI, ongoing work is investigating (i) variations in atmospheric O2 in the Archean to the Cambrian, (ii) characterization of the redox state of the oceans shortly before, during and after the Great Oxidation Event (GOE), and (iii) unraveling the complex connections between environmental oxygenation, global climate, and the evolution of life

Sulfur isotope evolution in sulfide ores from Western Alps: Assessing the influence of subduction-related metamorphism

Sulfides entering subduction zones can play an important role in the release of sulfur and metals to the mantle wedge and contribute to the formation of volcanic arc-associated ores. Fractionation of stable sulfur isotopes recorded by sulfides during metamorphism can provide evidence of fluid-rock interactions during metamorphism and give insights on sulfur mobilization. A detailed microtextural and geochemical study was performed on mineralized samples from two ocean floor-related sulfide deposits (Servette and Beth-Ghinivert) in high-pressure units of the Italian Western Alps, which underwent different metamorphic evolutions. The combination of microtextural investigations with d34S values from in situ ion probe analyses within individual pyrite and chalcopyrite grains allowed evaluation of the effectiveness of metamorphism in modifying the isotopic record and mobilizing sulfur and metals and have insights on fluid circulation within the slab. Textures and isotopic compositions inherited from the protolith are recorded at Beth-Ghinivert, where limited metamorphic recrystallization is attributed to limited interaction with metamorphic fluids. Isotopic modification by metamorphic processes occurred only at the submillimeter scale at Servette, where local interactions with infiltrating hydrothermal fluid are recorded by metamorphic grains. Notwithstanding the differences recorded by the two deposits, neither underwent intensive isotopic reequilibration or records evidence of intense fluid-rock interaction and S mobilization during metamorphism. Therefore, subducted sulfide deposits dominated by pyrite and chalcopyrite are unlikely to release significant quantities of sulfur to the mantle wedge and to arc magmatism sources at metamorphic grades below the lower eclogite facies

Observation of Hadronic W Decays in t-tbar Events with the Collider Detector at Fermilab

We observe hadronic W decays in t-tbar -> W (-> l nu) + >= 4 jet events using a 109 pb-1 data sample of p-pbar collisions at sqrt{s} = 1.8 TeV collected with the Collider Detector at Fermilab (CDF). A peak in the dijet invariant mass distribution is obtained that is consistent with W decay and inconsistent with the background prediction by 3.3 standard deviations. From this peak we measure the W mass to be 77.2 +- 4.6 (stat+syst) GeV/c^2. This result demonstrates the presence of two W bosons in t-tbar candidates in the W (-> l nu) + >= 4 jet channel.Comment: 20 pages, 4 figures, submitted to PR

Measurement of the lepton charge asymmetry in W-boson decays produced in p-pbar collisions

We describe a measurement of the charge asymmetry of leptons from W boson decays in the rapidity range 0 enu, munu events from 110+/-7 pb^{-1}of data collected by the CDF detector during 1992-95. The asymmetry data constrain the ratio of d and u quark momentum distributions in the proton over the x range of 0.006 to 0.34 at Q2 \approx M_W^2. The asymmetry predictions that use parton distribution functions obtained from previously published CDF data in the central rapidity region (0.0<|y_l|<1.1) do not agree with the new data in the large rapidity region (|y_l|>1.1).Comment: 13 pages, 3 tables, 1 figur