Protective role of endogenous carbon monoxide in hepatic microcirculatory dysfunction after hemorrhagic shock in rats

Maintenance of hepatic microcirculatory flow after ischemia of the liver is essential to prevent hepatic dysfunction. Thus, we determined the differential role of carbon monoxide (CO) and nitric oxide (NO) in the intrinsic control of sinusoidal perfusion, mitochondrial redox state, and bile production in the isolated perfused rat liver after hemorrhagic shock. Administration of tin protoporphyrin-IX (50 �M), a specific inhibitor of the CO generating enzyme heme oxygenase, caused a decrease in sinusoidal flow that was more pronounced after shock compared with sham shock, as determined by in situ epifluorescence microscopy. This was associated with a shift in hepatocellular redox potential to a more reduced state (increased fluorescence intensity of reduced pyridine nucleotides in hepatocytes, decreased acetoacetate/�-hydroxybutyrate ratio in the perfusate) and a profound reduction in bile flow. In sharp contrast, the preferential inhibitor of the inducible isoform of NO synthase S-methylisothiourea sulfate (100 �M) did not affect sinusoidal flow, hepatic redox state, or function. This indicates that 1.) endogenously generated CO preserves sinusoidal perfusion after hemorrhagic shock, 2.) protection of the hepatic microcirculation by CO may serve to limit shock-induced liver dysfunction, and 3.) in contrast to CO, inducible NO synthase-derived NO is of only minor importance for the intrinsic control of hepatic perfusion and function under these conditions. (J. Clin Invest. 1998. 102:1220– 1228.) Key words: liver • microcirculation • nitric oxide • heme oxygenase • oxidation reductio

The Auriga Nunataks shear zone: Mesozoic transfer faulting and arc deformation in northwest Palmer Land, Antarctica

The Auriga Nunataks shear zone places new tectonic and temporal constraints on the Mesozoic evolution of West Antarctica. The shear zone is a long-lived, arc-orthogonal, ductile transfer fault that preserves a history of regional Mesozoic compressional basement deformation and extensional arc pluton emplacement in the Antarctic Peninsula magmatic arc. It forms an east-west trending positive flower structure 2.4 km wide, exposed along 5 km of strike. Marble, graphite-bearing pyroxene-granulite, granodiorite-diorite, amphibolite, and gabbro are deformed to mylonite and marble-hosted tectonic breccia. The Mesozoic history of the shear zone is interpreted as follows: emplacement of granodiorite-diorite at circa 206 Ma during Early Jurassic dextral transtension and metamorphism that peaked at circa 188 Ma (D1), brecciation of marble and mylonitization of gneiss by Late Jurassic to Early Cretaceous sinistral shear during the peninsula-wide Palmer Land orogeny (D2), Early Cretaceous dextral transtension with emplacement of gabbro and garnet leucogranite between 140 and 135 Ma (D3), and mid-Cretaceous, ocean-vergent thrusting and sinistral transpression between 125 Ma and 80 Ma, with a peak at circa 110 Ma that folded, mylonitized, and brecciated preexisting plutonic and metamorphic rocks (D4); this is responsible for the current geometry of the shear zone. The Auriga Nunataks shear zone transferred motion between arc-parallel compressional and extensional structural elements and by hosting plutons appears to have acted like a leaky transform fault during episodes of regional extension

Genome-wide association and large-scale follow up identifies 16 new loci influencing lung function

Pulmonary function measures reflect respiratory health and are used in the diagnosis of chronic obstructive pulmonary disease. We tested genome-wide association with forced expiratory volume in 1 second and the ratio of forced expiratory volume in 1 second to forced vital capacity in 48,201 individuals of European ancestry with follow up of the top associations in up to an additional 46,411 individuals. We identified new regions showing association (combined P < 5 × 10?8) with pulmonary function in or near MFAP2, TGFB2, HDAC4, RARB, MECOM (also known as EVI1), SPATA9, ARMC2, NCR3, ZKSCAN3, CDC123, C10orf11, LRP1, CCDC38, MMP15, CFDP1 and KCNE2. Identification of these 16 new loci may provide insight into the molecular mechanisms regulating pulmonary function and into molecular targets for future therapy to alleviate reduced lung function

Atmospheric Composition Change: Ecosystems-Atmosphere interactions

Ecosystems and the atmosphere: This review describes the state of understanding the processes involved in the exchange of trace gases and aerosols between the earth's surface and the atmosphere. The gases covered include NO, NO2, HONO, HNO3, NH3, SO2, DMS, Biogenic VOC, O3, CH4, N2O and particles in the size range 1 nm–10 μm including organic and inorganic chemical species. The main focus of the review is on the exchange between terrestrial ecosystems, both managed and natural and the atmosphere, although some new developments in ocean–atmosphere exchange are included. The material presented is biased towards the last decade, but includes earlier work, where more recent developments are limited or absent. New methodologies and instrumentation have enabled, if not driven technical advances in measurement. These developments have advanced the process understanding and upscaling of fluxes, especially for particles, VOC and NH3. Examples of these applications include mass spectrometric methods, such as Aerosol Mass Spectrometry (AMS) adapted for field measurement of atmosphere–surface fluxes using micrometeorological methods for chemically resolved aerosols. Also briefly described are some advances in theory and techniques in micrometeorology. For some of the compounds there have been paradigm shifts in approach and application of both techniques and assessment. These include flux measurements over marine surfaces and urban areas using micrometeorological methods and the up-scaling of flux measurements using aircraft and satellite remote sensing. The application of a flux-based approach in assessment of O3 effects on vegetation at regional scales is an important policy linked development secured through improved quantification of fluxes. The coupling of monitoring, modelling and intensive flux measurement at a continental scale within the NitroEurope network represents a quantum development in the application of research teams to address the underpinning science of reactive nitrogen in the cycling between ecosystems and the atmosphere in Europe. Some important developments of the science have been applied to assist in addressing policy questions, which have been the main driver of the research agenda, while other developments in understanding have not been applied to their wider field especially in chemistry-transport models through deficiencies in obtaining appropriate data to enable application or inertia within the modelling community. The paper identifies applications, gaps and research questions that have remained intractable at least since 2000 within the specialized sections of the paper, and where possible these have been focussed on research questions for the coming decade

Fluxes and concentrations of volatile organic compounds from a South-East Asian tropical rainforest

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