bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper‐induced oxidative stress in Saccharomyces cerevisiae targets enzymes of the glycolytic pathway
Authors: Shanmuganathan Anupama , Avery Simon V. , Willetts Sylvia A. , Houghton John E.
Published: December 2003

Increased cellular levels of reactive oxygen species are known to arise during exposure of organisms to elevated metal concentrations, but the consequences for cells in the context of metal toxicity are poorly characterized. Using two‐dimensional gel electrophoresis, combined with immunodetection of protein carbonyls, we report here that exposure of the yeast Saccharomyces cerevisiae to copper causes a marked increase in cellular protein carbonyl levels, indicative of oxidative protein damage. The response was time dependent, with total‐protein oxidation peaking approximately 15 min after the onset of copper treatment. Moreover, this oxidative damage was not evenly distributed among the expressed proteins of the cell. Rather, in a similar manner to peroxide‐induced oxidative stress, copper‐dependent protein carbonylation appeared to target glycolytic pathway and related enzymes, as well as heat shock proteins. Oxidative targeting of these and other enzymes was isoform‐specific and, in most cases, was also associated with a decline in the proteins’ relative abundance. Our results are consistent with a model in which copper‐induced oxidative stress disables the flow of carbon through the preferred glycolytic pathway, and promotes the production of glucose‐equivalents within the pentose phosphate pathway. Such re‐routing of the metabolic flux may serve as a rapid‐response mechanism to help cells counter the damaging effects of copper‐induced oxidative stress.
Distinct in vitro interaction pattern of dopamine receptor subtypes with adaptor proteins involved in post‐endocytotic receptor targeting
Authors: Heydorn Arne , Søndergaard Birgitte P , Hadrup Niels , Holst Birgitte , Haft Carol Renfrew , Schwartz Thue W
Published: December 2003

The mechanisms underlying targeted sorting of endocytosed receptors for recycling to the plasma membrane or degradation in lysosomes are poorly understood. In this report, the C‐terminal tails of the five dopamine receptors (D1–D5) were expressed as glutathione S‐transferase (GST) fusion proteins and studied for their interaction with ezrin–radixin–moesin‐binding phosphoprotein 50 (EBP50) and N‐ethylmaleimide‐sensitive factor (NSF), which are known to be involved in post‐endocytic recycling of receptors back to the plasma membrane, and with sorting nexin 1 (SNX1), known to be involved in targeting receptors to lysosomal degradation. EBP50 did not bind any of the dopamine receptor tails. NSF bound strongly to D1 and D5 and only weakly to D2, D3 and D4. However, SNX1 clearly distinguished between D1 and D5, as only D5 bound strongly to this protein. This report shows that there are distinct interaction patterns for NSF and SNX1 to the various dopamine receptor subtypes.
Labor augmentation in an Egyptian teaching hospital
Authors: Khalil K. , Cherine M. , Elnoury A. , Sholkamy H. , Breebaart M. , Hassanein N.
Published: December 2003

Objectives: The study documented facility‐based obstetric practices for normal labor in Egypt for the first time, to determine their relationship to evidence‐based medicine. This paper describes the labor augmentation pattern observed. Methods: 176 cases of normal labor were observed by medically‐trained observers using a checklist. Ward activities were also documented. Observed women were interviewed postpartum and all findings were shared with the providers for their feedback. Results: Labor was augmented in 91% (165) of the labors observed; this was inappropriate for 93% or 154 women. Reasons for inappropriateness were: oxytocin ordered at the first vaginal exam (41%); in spite of intact membranes (36%), at the time of membrane rupture (42%), in spite of good progress (24%), or a combination of these. The monitoring of oxytocin‐receiving women and their babies was inadequate. Conclusions: Labor augmentation and monitoring deviated from evidence‐based guidelines. Obstacles to implementing protocols need to be explored.
Apical left ventricular aneurysm without atrio‐ventricular block due to a lamin A/C gene mutation
Authors: Forissier Jean‐François , Bonne Gisèle , Bouchier Christiane , Duboscq‐Bidot Laetitia , Richard Pascale , Wisnewski Claudine , Briault Sylvain , Moraine Claude , Dubourg Olivier , Schwartz Ketty , Komajda Michel
Published: December 2003

Background:

Mutations in LMNA gene encoding two ubiquitously expressed nuclear proteins, lamins A and C, give rise to up to 7 different pathologies affecting specific tissues. Three of these disorders affect cardiac and/or skeletal muscles with atrio‐ventricular conduction disturbances, dilated cardiomyopathy and sudden cardiac death as common features.

Results:

A new LMNA mutation (1621C>T, R541C) was found in two members of a French family with a history of ventricular rhythm disturbances and an uncommon form of systolic left ventricle dysfunction. The two patients: the proband and his daughter, were affected and exhibited an atypical form of dilated cardiomyopathy with an unexplained left ventricle aneurysm revealed by ventricular rhythm disturbances without atrio‐ventricular block.

Conclusion:

This finding reinforces the highly variable phenotypic expression of LMNA mutation and emphasizes the fact that LMNA mutations can be associated with different cardiac phenotypes.
Determinants of insulin sensitivity in chronic heart failure
Authors: Sabelis L.W.E. , Senden P.J. , Zonderland M.L. , van de Wiel A. , Wielders J.P.M. , Huisveld I.A. , van Haeften T.W. , Mosterd W.L.
Published: December 2003

Objective:

To describe the determinants of insulin sensitivity (IS) in chronic heart failure (CHF), we created a model in which the influence of lifestyle factors and etiology of heart failure on IS were incorporated concomitantly with age, left ventricular ejection fraction (LVEF) and parameters of body composition.

Design:

Observational cohort study.

Setting:

Outpatient clinic for chronic heart failure.

Patients:

Fifty‐seven male CHF patients [NYHA class II–III, age 61±9 years, body mass index (BMI) 26.9±3.3 kg/m2 (mean±S.D.)].

Interventions:

Euglycemic hyperinsulinemic clamp, cycle ergometry, anthropometric measurements, LVEF and a physical activity questionnaire. Main outcome measures: A model explaining the variance of IS in CHF. Results: IS was 18.2±8.6 μg·kg−1·min−1·mU−1·l−1, fasting insulin level was 15.9±11.0 mU/l and fasting glucose level was 5.5±0.6 mmol/l. Peak was 19.1±4.9 ml·kg−1·min−1 and LVEF 26.2±7.1%. IS was inversely associated with fasting insulin concentration (r=−0.50, P<0.001) and BMI (r=−0.54, P<0.001). After controlling for BMI, IS also revealed a correlation with age (r=−0.36, P<0.01). The model explained 60% of variance in IS: BMI contributed 20%, smoking 17%, age 17% and physical activity in daily life (DPA) 16% (all P<0.05) to the variance of IS, whereas LVEF (9%) and etiology of heart failure (8%) contributed moderately.

Conclusions:

In CHF patients, IS is for a major part predicted by BMI, smoking, age, daily physical activity, LVEF and etiology of heart failure.
Evidence of biological activity in Hawaiian subsurface basalts
Authors: Fisk M. R. , Storrie‐Lombardi M. C. , Douglas S. , Popa R. , McDonald G. , Di Meo‐Savoie C.
Published: December 2003

The Hawaii Scientific Drilling Program (HSDP) cored and recovered igneous rock from the surface to a depth of 3109 m near Hilo, Hawaii. Much of the deeper parts of the hole is composed of hyaloclastite (fractured basalt glass that has been cemented in situ with secondary minerals). Some hyaloclastite units have been altered in a manner attributed to microorganisms in volcanic rocks. Samples from one such unit (1336 m to 1404 m below sea level) were examined to test the hypothesis that the alteration was associated with microorganisms. Deep ultraviolet native fluorescence and resonance Raman spectroscopy indicate that nucleic acids and aromatic amino acids are present in clay inside spherical cavities (vesicles) within basalt glass. Chemical mapping shows that phosphorus and carbon were enriched at the boundary between the clay and volcanic glass of the vesicles. Environmental scanning electron microscopy (ESEM) reveals two to three micrometer coccoid structures in these same boundaries. ESEM‐linked energy dispersive spectroscopy demonstrated carbon, phosphorous, chloride, and magnesium in these bodies significantly differing from unoccupied neighboring regions of basalt. These observations taken together indicate the presence of microorganisms at the boundary between primary volcanic glass and secondary clays. Amino acids and nucleic acids were extracted from bulk samples of the hyaloclastite unit. Amino acid abundance was low, and if the amino acids are derived from microorganisms in the rock, then there are less than 100,000 cells per gram of rock. Most nucleic acid sequences extracted from the unit were closely related to sequences of Crenarchaeota collected from the subsurface of the ocean floor.
Three‐dimensional numerical simulation of fluid flow and heat transport within the Barbados Ridge accretionary complex
Authors: Cutillo Paula A. , Screaton Elizabeth J. , Ge Shemin
Published: December 2003

The thickness of the Barbados accretionary prism varies along strike. The increased thickness of the prism to the south is believed to affect the transport of heat by fluids, resulting in anomalously high heat flow at the deformation front. We utilized a coupled three‐dimensional numerical fluid flow and heat transport model to investigate the effect of variable accretionary prism thickness on fluid flow patterns and heat transport in the décollement zone. The variation in sediment thickness produced along‐strike fluid flow in the more permeable décollement. Although surface heat flow is higher for simulations where flow occurs along both the décollement and underthrust sediments, the resultant advective heat transport was not sufficient to appreciably raise steady state surface heat flow at the latitude of the Ocean Drilling Program transect. Simulated temperatures in the décollement were consequently much lower than in situ borehole measurements, suggesting an additional source of warmer fluid. We then investigated the transient hydrologic and thermal response of the system to enhanced fault permeability. Model results provide insight into the degree to which episodic faulting may drive fluid flow and heat transport within subduction complexes. A transient scenario in which décollement permeability was increased two orders of magnitude with fluid flow along both the décollement and underthrust sediments caused the temperature gradient at the location of the drill sites to increase by a factor of two within 7100 years. The results of the three‐dimensional numerical simulations indicate that while both along‐strike advective heat transport and transient fluid flow events should be considered in the heat flow distribution of the northern Barbados accretionary complex, the effects of episodic fluid flow are more significant.
Seismic stratigraphy of the West Shetland Drift: Implications for late Neogene paleocirculation in the Faeroe‐Shetland gateway
Authors: Knutz Paul C. , Cartwright Joseph
Published: December 2003

The morphology and anatomy of a late Neogene contourite drift on the British margin of the Faeroe‐Shetland Channel is investigated in unprecedented detail using industrial two‐dimensional and three‐dimensional seismic data. The West Shetland Drift is constructed by a succession of mounded, asymmetric strata that in the basin and on the midslope has accumulated on a regional unconformity of early Pliocene age. The midslope component of the drift system forms a 400 m thick convex, elongate sedimentary body that can be traced from the outlet of the Norwegian Channel and 250 km southwest along the Shetland margin. Contourite drifts occupying the basin are evident as a succession of sheeted‐mounded and wavy migrating units intercalated by three mega‐debrite sequences. The seismic architecture of the West Shetland Drift and tentative age estimates of its bounding surfaces suggests that it formed rapidly (∼5–10 cm kyr−1) by alongslope transport of hemipelagic sediments derived from the NW European shelf. The change from erosion/nondeposition to enhanced contourite drift accumulation during the early Pliocene suggests that a moderate thermohaline current regime prevailed in the Faeroe‐Shetland Channel prior to the main phase of Northern Hemisphere glaciation at 3.0–2.5 Ma. A reduction in meridional heat transport associated with a decrease in the flux of North Atlantic deep waters may have been an important factor for the growth of Northern Hemisphere ice sheets.
Backstop geometry and accretionary mechanics of the Sunda margin
Authors: Kopp Heidrun , Kukowski Nina
Published: December 2003

The convergent Sunda margin off Indonesia displays all geological features characteristic of an accretion‐dominated subduction zone. A combined interpretation of prestack depth‐migrated seismic reflection data and velocity information gained from refraction studies is supplemented by high‐resolution bathymetric data and for the first time allows the exact mapping of backstop regimes. Initially, the outer high evolved as material was pushed against a static rigid arc framework backstop underlying a forearc basin. Increasing material strength of the outer high due to lithification formed a dynamic backstop, which controls accretion today. An out‐of‐sequence thrust marks the transition from the recent active frontal accretionary prism to the outer high and may be traced in the seismic and bathymetric data over the whole extent of the study area. The existence of a static as well as a dynamic backstop controls the forearc geometry and is associated with the segmentation of the forearc, which is observed in regimes of frontal as well as of oblique subduction. Mass balance calculations, which account for porosity changes and metamorphism, indicate a subduction history dominated by accretionary processes since the late Eocene. Accretion is associated with the low values of basal friction inferred for the Sunda margin. Structural investigations of conjugate fault planes indicate a very weak basal detachment. Effective stress analyses reveal that intrinsically weak material causes the high strength ratio of the detachment to the overlying sediments, whereas overpressuring within the frontal accretionary prism is negligible.
Thermal response of the tropical tropopause region to solar ultraviolet variations
Authors: Hood L. L.
Published: December 2003

Correlative and linear regression analyses of National Centers for Environmental Prediction (NCEP) temperature data in the tropical lower stratosphere and upper troposphere confirm the existence of a thermal response to solar ultraviolet variations occurring on the time scale of the solar rotation period. The maximum response occurs near the 100 hPa level (approximately 16 km altitude) at a phase lag of 2 ± 2 days with an amplitude of 0.24 ± 0.07 Kelvin for a change in the Mg II core‐to‐wing ratio of 0.01 (approximately equivalent to a 4% change in solar UV flux at a wavelength near 200 nm). It is suggested that the observed thermal response near the tropical tropopause is caused by changes in upwelling rates induced by the direct effects of solar UV forcing on photochemistry, radiative heating, and dynamics in the upper stratosphere.
Nitric acid photolysis on surfaces in low‐NOx environments: Significant atmospheric implications
Authors: Zhou Xianliang , Gao Honglian , He Yi , Huang Gu , Bertman Steven B. , Civerolo Kevin , Schwab James
Published: December 2003

Nitric acid (HNO3) is the dominant end product of NOx (= NO + NO2) oxidation in the troposphere, and its dry deposition is considered to be a major removal pathway for the atmospheric reactive nitrogen. Here we present both field and laboratory results to demonstrate that HNO3 deposited on ground and vegetation surfaces may undergo effective photolysis to form HONO and NOx, 1–2 orders of magnitude faster than in the gas phase and aqueous phase. With this enhanced rate, HNO3 photolysis on surfaces may significantly impact the chemistry of the overlying atmospheric boundary layer in remote low‐NOx regions via the emission of HONO as a radical precursor and the recycling of HNO3 deposited on ground surfaces back to NOx.
Bulk processes prior to the 2001 Mount Etna eruption, highlighted through microgravity studies
Authors: Carbone Daniele , Budetta Gennaro , Greco Filippo
Published: December 2003

Discrete gravity data were acquired at Mount Etna over a period lasting more than a year and spanning the July–August 2001 flank eruption. The gravity measurements were made using a Scintrex CG‐3M gravimeter along two profiles of Etna's gravity network. The gravity data indicate that during the second half of 2000, a mass increase of 2 × 1010 kg took place about 1.5 km below the summit craters zone. It is thought to be due to a magma accumulation. A comparable mass decrease was detected during a 4‐month period encompassing the eruption which is thought to be the result of withdrawal of the same magma. The gravity data also show that a mass decrease of 2.5 × 1011 kg occurred between January and 19 July 2001 (2 days after the start of the eruption), below the southeastern sector of the volcano, within a volume around 2.5 km below sea level. This decrease was followed by a sudden increase that, in 14 days, partially compensated the previous variation. Since many tensional earthquakes took place during the first half of 2001, within the same source volume of the inferred mass decrease, it is reasonable to assume that the variation observed before the eruption reflects the formation of new voids by tectonic tensile stresses below the volcano edifice. Magma was emplaced along the new formed path from a deep storage to higher levels of Etna's plumbing system, setting off the eruption and causing the gravity increase observed soon after its start. Vulcanological, petrological, and ground deformation studies agree with the assumption of a batch of magma coming directly from a deep storage to have supplied most material extruded during the eruption.
Exchange between the upper tropical troposphere and the lower stratosphere studied with aircraft observations
Authors: Tuck A. F. , Hovde S. J. , Kelly K. K. , Mahoney M. J. , Proffitt M. H. , Richard E. C. , Thompson T. L.
Published: December 2003

Exchange between the upper tropical troposphere and the lower stratosphere is considered by examining WB57F and ER‐2 aircraft observations of water, ozone, wind, and temperature in the potential temperature range 360 < θ < 420 K. These processes are examined in part by using the technique of unified scale invariance on the airborne data, as has been done previously for the lower stratospheric polar vortex. Scale invariance is found, on scales from a few hundred meters to the maximum flown, 2700 km (25 great circle degrees). The results apply both to vertical exchange at the tropical tropopause and to isentropic exchange at the subtropical jet stream. All scales participate in the maintenance of the mean state, with substantial contributions from relatively infrequent but intense events in the long tails of the probability distributions. Past data are examined and found to fit this general framework. A unique mapping of tropical tropopause temperature to the total hydrogen content of the middleworld and overworld should not be expected; the head of the “tape recorder” is at 50–60 hPa rather than 90–100 hPa. The tropical tropopause is observed at potential temperatures θT greater than the maximum moist static surface values θW, such that θT − θW varies between 10 K in fall and up to 40 K in spring. The meridional gradient of θT is directed from the subtropical jet stream to the inner tropics, with θT declining by approximately 10 K from near 30°N to near 10°N in the vicinity of 95°W. The maintenance of these θT values is discussed. Total water (measured as the sum of vapor and vaporized ice) and ozone, major absorbers of solar radiation and emitters/absorbers of terrestrial infrared radiation, show scale invariance in the upper tropical troposphere. The implications of this result for the notion of a conservative cascade of energy via fluid dynamics from the largest to the smallest scales are discussed. The scaling exponents Hz for total water and ozone in the upper tropical troposphere are not the value, 5/9, expected for a passive scalar, probably indicating the presence of sources and/or sinks operating faster than mixing.
Retrieval of temperature and tangent altitude pointing from limb emission spectra recorded from space by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS)
Authors: von Clarmann T. , Glatthor N. , Grabowski U. , Höpfner M. , Kellmann S. , Kiefer M. , Linden A. , Tsidu G. M. , Milz M. , Steck T. , Stiller G. P. , Wang D. Y. , Fischer H. , Funke B. , Gil‐López S. , López‐Puertas M.
Published: December 2003

Retrieval of abundances of atmospheric species from limb infrared emission spectra requires accurate knowledge of the pointing of the instrument in terms of elevation, as well as temperature and pressure profiles. An optimal estimation‐based method is presented to infer these quantities from measured spectra. The successful and efficient joint retrieval of these largely correlated quantities depends strongly on the proper selection of the retrieval space, the selection of spectral microwindows, and the choice of reasonable constraints which force the solution to be stable. The proposed strategy was applied to limb emission spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on board the Envisat research satellite in order to validate the instrument pointing information based on the satellite's orbit and attitude control system which uses star tracker information as a reference. Both systematic and periodic pointing calibration errors were detected, which meanwhile have been corrected to a major part. Furthermore, occasional pitch jumps were detected, which could be assigned to parameter uploads to the satellite's orbit and attitude control system. It has been shown that in general, it is justified to assume local thermodynamic equilibrium below 60 km for these purposes. The retrieval method presented has been proven to be suitable for independent monitoring of MIPAS line‐of‐sight pointing.
Mars Exploration Rover Engineering Cameras
Authors: Maki J. N. , Bell J. F. , Herkenhoff K. E. , Squyres S. W. , Kiely A. , Klimesh M. , Schwochert M. , Litwin T. , Willson R. , Johnson A. , Maimone M. , Baumgartner E. , Collins A. , Wadsworth M. , Elliot S. T. , Dingizian A. , Brown D. , Hagerott E. C. , Scherr L. , Deen R. , Alexander D. , Lorre J.
Published: December 2003

NASA's Mars Exploration Rover (MER) Mission will place a total of 20 cameras (10 per rover) onto the surface of Mars in early 2004. Fourteen of the 20 cameras are designated as engineering cameras and will support the operation of the vehicles on the Martian surface. Images returned from the engineering cameras will also be of significant importance to the scientific community for investigative studies of rock and soil morphology. The Navigation cameras (Navcams, two per rover) are a mast‐mounted stereo pair each with a 45° square field of view (FOV) and an angular resolution of 0.82 milliradians per pixel (mrad/pixel). The Hazard Avoidance cameras (Hazcams, four per rover) are a body‐mounted, front‐ and rear‐facing set of stereo pairs, each with a 124° square FOV and an angular resolution of 2.1 mrad/pixel. The Descent camera (one per rover), mounted to the lander, has a 45° square FOV and will return images with spatial resolutions of ∼4 m/pixel. All of the engineering cameras utilize broadband visible filters and 1024 × 1024 pixel detectors.
Turbulent flow over three‐dimensional dunes: 2. Fluid and bed stresses
Authors: Maddux T. B. , McLean S. R. , Nelson J. M.
Published: December 2003

Dunes formed in response to fluid flow exert a total boundary stress on the fluid that is made up of form drag and skin friction, the latter of which is generally considered important for predicting sediment transport and dune evolution. Previous research has used various methods to estimate the total stress and its subcomponents, with recent work suggesting the application of a spatial average to the equations of motion. A complete, three‐dimensional (3‐D) form of this analysis is derived and applied to recent measurements of turbulent open‐channel flow over 3‐D dunes. Spatial averages of Reynolds shear stresses over 3‐D dunes cannot be used to predict total boundary shear stress. However, estimations of total boundary shear stress from the spatially averaged equations of motion agree with not only the sum of form drag and skin friction but also the direct measurements of average free surface slope. Form‐induced stresses from secondary circulations augment the relatively low Reynolds shear stresses over the 3‐D dunes. These low turbulence levels have ramifications for sediment transport predictions, in that use of the total boundary shear stress in prediction of sediment transport over 3‐D dunes must account for these low turbulence levels so as not to overpredict transport rates.
Sensitivity of the Atlantic Intertropical Convergence Zone to Last Glacial Maximum boundary conditions
Authors: Chiang John C. H. , Biasutti Michela , Battisti David S.
Published: December 2003

Recent paleoproxy records suggest that the mean latitude of the Atlantic Intertropical Convergence Zone (ITCZ) varied synchronously with North Atlantic climate over a range of timescales throughout the Holocene and Last Glacial Maximum. We show that the present‐day “meridional mode” of atmosphere‐ocean variability in the tropical Atlantic is a potentially useful model for understanding these paleoclimate changes. The tropical Atlantic in a coupled atmospheric general circulation and slab ocean model responds to Last Glacial Maximum conditions with a southward displacement of the ITCZ. This response arises primarily through the land ice sheet that forces increased North Atlantic trades analogous to the forcing on the present‐day meridional mode. Changes to sea ice coverage and to ocean heat transport associated with a weakened Atlantic thermohaline circulation also cause a meridional mode response, though through different mechanisms. Our results highlight the potential for tropical Atlantic paleoclimate to be driven from the high latitude influences, in particular, land ice on glacial‐interglacial timescales.
Electrophysiological effects of 5‐hydroxytryptamine on isolated human atrial myocytes, and the influence of chronic β‐adrenoceptor blockade
Authors: Pau Davide , Workman Antony J , Kane Kathleen A , Rankin Andrew C
Published: December 2003

5‐Hydroxytryptamine (5‐HT) has been postulated to play a proarrhythmic role in the human atria via stimulation of 5‐HT4 receptors.

The aims of this study were to examine the effects of 5‐HT on the L‐type Ca2+ current (ICaL) action potential duration (APD), the effective refractory period (ERP) and arrhythmic activity in human atrial cells, and to assess the effects of prior treatment with β‐adrenoceptor antagonists.

Isolated myocytes, from the right atrial appendage of 27 consenting patients undergoing cardiac surgery who were in sinus rhythm, were studied using the whole‐cell perforated patch‐clamp technique at 37°C.

5‐HT (1 nM–10 μM) caused a concentration‐dependent increase in ICaL, which was potentiated in cells from β‐blocked (maximum response to 5‐HT, Emax=299±12% increase above control) compared to non‐β‐blocked patients (Emax=220±6%, P<0.05), but with no change in either the potency (log EC50: −7.09±0.07 vs −7.26±0.06) or Hill coefficient (nH: 1.5±0.6 vs 1.5±0.3) of the 5‐HT concentration–response curve.

5‐HT (10 μM) produced a greater increase in the APD at 50% repolarisation (APD50) in cells from β‐blocked patients (of 37±10 ms, i.e. 589±197%) vs non‐β‐blocked patients (of 10±4 ms, i.e. 157±54%; P<0.05). Both the APD90 and the ERP were unaffected by 5‐HT.

Arrhythmic activity was observed in response to 5‐HT in five of 17 cells (29%) studied from β‐blocked, compared to zero of 16 cells from the non‐β‐blocked patients (P<0.05).

In summary, the 5‐HT‐induced increase in calcium current was associated with a prolonged early plateau phase of repolarisation, but not late repolarisation or refractoriness, and the enhancement of these effects by chronic β‐adrenoceptor blockade was associated with arrhythmic potential.

British Journal of Pharmacology (2003) 140, 1434–1441. doi:10.1038/sj.bjp.0705553
Direct coronary vasodilator action of adrenomedullin is mediated by nitric oxide
Authors: Matteo R De , May C N
Published: December 2003

Increased circulating levels of adrenomedullin (ADM) cause peripheral vasodilatation and hypotension, accompanied by cardiac actions including tachycardia and increases in cardiac contractility, cardiac output, coronary conductance (CC) and coronary blood flow (CBF). It is unclear to what extent these cardiac effects are direct actions of ADM or secondary to the hypotension and altered cardiac loading.

The direct cardiac actions of ADM were examined in conscious sheep previously implanted with aortic and coronary flow probes, and an indwelling left coronary artery cannula. Responses to infusion of ADM (0.5 μg kg−1 h−1 for 1 h) into the left coronary artery or jugular vein were compared (n=6). The effect of blockade of nitric oxide (NO) synthase with intracoronary (i.c.) Nω‐nitro‐L‐arginine (L‐NNA; 1.5 mg kg−1 h−1), infused for 2 h before and during ADM infusion, was assessed to determine whether the responses to ADM were mediated by NO (n=5).

I.c. ADM caused large and sustained increases in CC (0.35±0.07–0.55±0.13 ml min−1 mmHg−1, P<0.05) and CBF (28±6–42±9 ml min−1, P<0.05), but had no effect on arterial pressure or indices of cardiac contractility (first differential of the upstroke of systole and peak aortic flow rate). Intravenous infusion of ADM had no effects.

I.c. L‐NNA, at a dose that abolished the coronary vasodilator action of acetylcholine, blocked ADM‐induced coronary vasodilatation.

In conclusion, ADM had a direct coronary vasodilator action that was mediated by release of endogenous NO and resulted in increased CBF. There was no evidence for a direct inotropic action of ADM.

British Journal of Pharmacology (2003) 140, 1414–1420. doi:10.1038/sj.bjp.0705572
Effects of A‐317491, a novel and selective P2X3/P2X2/3 receptor antagonist, on neuropathic, inflammatory and chemogenic nociception following intrathecal and intraplantar administration
Authors: McGaraughty Steve , Wismer Carol T , Zhu Chang Z , Mikusa Joseph , Honore Prisca , Chu Katharine L , Lee Chih‐Hung , Faltynek Connie R , Jarvis Michael F
Published: December 2003

We have recently reported that systemic delivery of A‐317491, the first non‐nucleotide antagonist that has high affinity and selectivity for blocking P2X3 homomeric and P2X2/3 heteromeric channels, is antinociceptive in rat models of chronic inflammatory and neuropathic pain. In an effort to further evaluate the role of P2X3/P2X2/3 receptors in nociceptive transmission, A‐317491 was administered either intrathecally or into the hindpaw of a rat in several models of acute and chronic nociception.

Intraplantar (ED50=300 nmol) and intrathecal (ED50=30 nmol) injections of A‐317491 produced dose‐related antinociception in the CFA model of chronic thermal hyperalgesia. Administration of A‐317491 by either route was much less effective to reduce thermal hyperalgesia in the carrageenan model of acute inflammatory hyperalgesia.

Intrathecal, but not intraplantar, delivery of A‐317491 attenuated mechanical allodynia in both the chronic constriction injury and L5‐L6 nerve ligation models of neuropathy (ED50=10 nmol for both models). Intrathecal injections of A‐317491 did not impede locomotor performance.

Both routes of injection were effective in reducing the number of nocifensive events triggered by the injection of formalin into a hindpaw. Nocifensive behaviors were significantly reduced in both the first and second phases of the formalin assay (intrathecal ED50=10 nmol, intraplantar ED50>300 nmol). Nocifensive behaviors induced by the P2X receptor agonist α,β‐meATP were also significantly reduced by intraplantar injection of A‐317491.

These data indicate that both spinal and peripheral P2X3/P2X2/3 receptors have significant contributions to nociception in several animal models of nerve or tissue injury. Intrathecal administration of A‐317491 appears to be more effective than intraplantar administration to reduce tactile allodynia following peripheral nerve injury.

British Journal of Pharmacology (2003) 140, 1381–1388. doi:10.1038/sj.bjp.0705574
Linkage and QTL mapping for Sus scrofa chromosome 1
Authors: Beeckmann P. , Schröffel J. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 1 (SSC1) have been produced using 10 markers in three different F2 families based on crosses of Meishan (M), Pietrain (P) and Wild Boar (W). The maps were similar for the different families and show higher paternal recombination, especially in the interval SW2130–SW803. Quantitative trait loci (QTLs) affecting body conformation, carcass composition, fat deposition and numbers of teats were identified in all three families. Major QTLs were mapped in chromosomal intervals centred at approximately 60, 120 and 170 cM. The QTLs explain up to 8.4% of phenotypic variance in the F2 generation. Pietrain QTL alleles were superior in comparison with Wild Boar and Meishan alleles for most of the trait values. Meishan alleles were associated with highest fat deposition. Additive gene effects were generally larger than dominance effects. QTL profiles on SSC1 differed between families, with the W × P family being most distinct.
Linkage and QTL mapping for Sus scrofa chromosome 3
Authors: Beeckmann P. , Schröffel J. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 3 (SSC3) were established on the basis of eight marker loci using three F2 families generated from crosses of Meishan (M), Pietrain (P) and Wild Boar (W) founders. The maps were similar for the three families and in agreement with the published linkage maps. Recombination was significantly higher in maternal than in paternal meioses. Quantitative trait loci (QTLs), explaining up to 6.0% of the F2 phenotypic variance, were mapped for daily gain, carcass traits and meat quality in proximal and central intervals of SSC3. The QTLs detected were often family‐specific. Pietrain QTL alleles were superior for muscle traits in comparison with Meishan alleles, and Wild Boar QTL alleles caused lower values for fatness than Pietrain alleles.
Linkage and QTL mapping for Sus scrofa chromosome 4
Authors: Cepica S. , Stratil A. , Kopecny M. , Blazkova P. , Schröffel J. , Davoli R. , Fontanesi L. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 4 (SSC4) based on 19 markers were similar in lengths for three F2‐families [Wild Boar (W), Meishan (M) and Pietrain (P) crosses] and in agreement with the previously published maps. Quantitative trait loci (QTLs) on SSC4 affect mainly muscle and fat mass. Compared with others, Pietrain alleles were associated with longer carcass, higher body weight and higher meat content. In all three families, the profiles of F ratio values for these traits showed peaks close to the positions of candidate genes V‐ATPase, ATP1A2 and ATP1B1. Additional more proximally mapped QTLs, significant at the p < 0.05 chromosome‐wide level, were found in the M × P and W × P families. The W × M family revealed highly significant QTLs located in the vicinity of AMPD1 and NGFB. The SSC4 QTLs explained up to 12% of F2 phenotypic variance.
Linkage and QTL mapping for Sus scrofa chromosome 5
Authors: Lee S. S. , Chen Y. , Moran C. , Stratil A. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 5 (SSC5) were constructed using up to 10 markers in three informative F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The map lengths differed among the families. In the M × P family, the MYF5 locus was linkage mapped between SW995 and SW967. Relatively few quantitative trait loci (QTLs) were observed on SSC5 explaining a maximum of 5.8% of phenotypic variance in the F2 generation. The presence and position of QTLs were not consistent among families. The Meishan and Wild Boar QTL allele effects were inferior compared with Pietrain allele effects. The additive effects were small and reasonably strong dominance‐effects were observed. QTLs affecting conductivity in the W × M family and food conversion ratio in the M × P family mapped near MYF5, while the QTL affecting conductivity in the M × P family was located near IGF1.
Linkage and QTL mapping for Sus scrofa chromosome 7
Authors: Yue G. , Stratil A. , Cepica S. , Schröffel J. , Schröffelova D. , Fontanesi L. , Cagnazzo M. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 7 (SSC7) for three informative F2 families, based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses, were constructed using 16 marker loci. Maps were consistent for the families, except the order of the markers PI2‐PO1A‐S0212 in the W × M family which was inverted in the M × P and W × P families. Important quantitative trait loci (QTLs) were localized in the region of the SLA complex in the M × P and W × M families. These explained up to 16% of F2 phenotypic variance for body conformation, fat deposition and muscling. In the W × P family, minor QTLs were mapped outside the SLA region. The highly significant QTL alleles were mainly additive (a > d). The Meishan alleles for QTL located in the SLA region were associated with higher head weights and carcass lengths, but with lower carcass fat contents than those from Wild Boar and Pietrain. The cryptic Meishan QTL allele, which reduces carcass fat, provides one of the first examples of transgressive segregation in animals and emphasizes that useful genetic variation can be hidden in the genetic background of a breed.
Linkage and QTL mapping for Sus scrofa chromosome 9
Authors: Cepica S. , Schröffel J. , Stratil A. , Hojný J. , Pierzchala M. , Kuryl J. , Brunsch C. , Sternstein I. , Davoli R. , Fontanesi L. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

Linkage and QTL maps of Sus scrofa chromosome 9 (SSC9) were constructed using 16 markers, with 13 to 15 used in three F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The LPR and SLN loci were integrated into the linkage map of SSC9 for the first time. Only a few quantitative trait loci (QTLs), explaining up to 5.1% of the F2 phenotypic variance, were identified on SSC9 with chromosome‐wide significant effects on growth and fattening in the W × P family and on weight of liver, growth and fat‐to‐meat ratio in the W × M family. No QTLs were found in the M × P family. Gene effects were mainly dominant in the W × P family. In the W × M family, Wild Boar QTL alleles for weight of liver were superior over Meishan alleles.
Linkage and QTL mapping for Sus scrofa chromosome 11
Authors: Dragos‐Wendrich M. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

Linkage and QTL maps of Sus scrofa chromosome 11 (SSC11) have been produced based on four microsatellite markers genotyped in three F2 families from Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The maps were similar across the families and in agreement with already published maps. Quantitative Trait Loci (QTLs) were identified in the W × M family and not in the M × P and W × P families. The QTLs affected live weight, loin and neck meat weight, back‐fat depth and food consumption, and explained up to 4.7% of the F2 phenotypic variance. Additive and dominance effects were similar in size. The Wild Boar QTL alleles led to higher trait values in comparison with Meishan alleles.
Linkage and QTL mapping for Sus scrofa chromosome 12
Authors: Yue G. , Schröffel J. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

The SSC12 (Sus scrofa chromosome 12) linkage and QTL maps were generated using 11 markers, of which seven to 10 have been used in the three F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. Linkage maps showed identical marker order among the families, but differed in total lengths. They were in agreement with the already published maps, except for the order SWR1021–SW605. Most quantitative trait loci (QTLs) affected fat or meat content in carcass, but were also found for some other traits (heart weight, CK20 values and teat number). They explained up to 5.4% of F2 phenotypic variance. Meishan alleles had stimulating effects on fat deposition and decreasing effects on lean content and CK20 value. The QTL profiles differed between families, with QTL effects in the vicinity of the GH1 locus found solely in the M × P family.
Linkage and QTL mapping for Sus scrofa chromosome 14
Authors: Dragos‐Wendrich M. , Sternstein I. , Brunsch C. , Moser G. , Bartenschlager H. , Reiner G. , Geldermann H.
Published: December 2003

The Sus scrofa chromosome 14 (SSC14) linkage maps, constructed using eight markers in three F2‐families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses, were similar for the different families. The detected quantitative trait loci (QTLs) explained up to 8.2% of the F2 phenotypic variance for carcass traits. They were located in the interval SW540 to SW2488 (containing the candidate loci ACTN2 and ACTA1) in the M × P and W × P families. A QTL for body weight at 35 days was mapped close to the candidate locus ACTN2 in the W × M family. In comparison with Pietrain QTL alleles, the effects of Meishan and Wild Boar alleles reduced meat content.
Linkage and QTL mapping for Sus scrofa chromosome 15
Authors: Kuryl J. , Pierzchala M. , Hojny J. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

The Sus scrofa chromosome 15 (SSC15) linkage maps were produced with six markers in three F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The maps were similar for the different families, with a higher rate of maternal recombination than paternal only in the M × P family. Quantitative trait loci (QTLs) for carcass composition (dressing yield, lean cuts and fat depth) explained up to 9% of F2 phenotypic variance in the W × P family and mapped near the marker S0148 (0 cM). Similar QTLs for fat depth were observed in the W × M family, where a minor QTL for dressing yield was mapped in the interval EAG–SW964 (approximately at 25 cM). No SSC15 QTL was found in the M × P family.
Linkage and QTL mapping for Sus scrofa chromosome 16
Authors: Pierzchala M. , Kuryl J. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

Linkage maps of Sus scrofa chromosome 16 (SSC16) were produced using five markers and three F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The maps were similar for the different families and in agreement with published maps. Quantitative trait loci (QTLs) for fattening, growth, meat quality and stress resistance were found in the M × P and W × P families, but not in the W × M family. QTLs for fattening and growth were mapped to the proximal end of SSC16, whereas QTLs for meat quality were located centrally or distally. The QTLs explained up to 5.9% of the F2 phenotypic variance.
Linkage and QTL mapping for Sus scrofa chromosome 17
Authors: Pierzchala M. , Cieslak D. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

Linkage and QTL maps of Sus scrofa chromosome 17 (SSC17) were analysed with five markers and in three F2 families based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The maps were similar across the three families and agree well with published maps. In the M × P family, new quantitative trait loci (QTLs) for growth and fat deposition were located in the vicinity of GHRH, whereas in the W × P family one minor QTLs for daily gain was detected. No QTL was found in the W × M family.
Linkage and QTL mapping for Sus scrofa chromosome X
Authors: Cepica S. , Reiner G. , Bartenschlager H. , Moser G. , Geldermann H.
Published: December 2003

The Sus scrofa chromosome X (SSCX) linkage and QTL maps, based on 11 markers, were investigated in F2 families generated from Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The linkage maps were similar for the three families and to the published USDA‐MARC.2 linkage map. Strongly supported quantitative trait loci (QTLs) for growth, fattening, meat quality and weight of head were mapped in the proximal part of SSCX of the M × P and W × P families, whilst QTLs for fat deposition and muscling mainly were assigned to the mid part of SSCX in the W × M and M × P families. The QTLs explained up to 13.7% of F2 phenotypic variance. Meishan QTL alleles led to increased fatness traits, while those of Pietrain tended to increased carcass and meat weights and to decreased meat quality.
Mesoscale regulation comes from the bottom‐up: intertidal interactions between consumers and upwelling
Authors: Nielsen Karina J. , Navarrete Sergio A.
Published: December 2003

Theory suggests that variation in resource supply should propagate up trophic webs influencing plant–herbivore interactions and abundances. Community regulation models have been tested in several ecosystems, but benthic marine ecologists have largely overlooked bottom‐up factors except at the largest spatial scales. We used naturally occurring variation in nutrient supply associated with upwelling intensity (over 10s of kilometre) to test community regulation models. Higher upwelling intensity was strongly associated with increased abundance of late‐successional, corticated algae, which in turn had apparent negative effects on ephemeral algae. Corticated algae were resistant to extant levels of herbivory. As a result, corticated algae were more abundant at sites of high upwelling intensity, while ephemeral algae were more abundant at sites of low upwelling intensity. We speculate that human removal of large grazers that can feed on corticated algae may interact with natural variation in nutrient supply to shift community structure over mesoscales.
Quantifying mortality of tropical rain forest trees using high‐spatial‐resolution satellite data
Authors: Clark David B. , Castro Carlomagno Soto , Alvarado Luis Diego Alfaro , Read Jane M.
Published: December 2003

Assessment of forest responses to climate change is severely hampered by the limited information on tree death on short temporal and broad spatial scales, particularly in tropical forests. We used 1‐m resolution panchromatic IKONOS and 0.7‐m resolution QuickBird satellite data, acquired in 2000 and 2002, respectively, to evaluate tree death rates at the La Selva Biological Station in old‐growth Tropical Wet Forest in Costa Rica, Central America. Using a calibration factor derived from ground inspection of tree deaths predicted from the images, we calculated a landscape‐scale annual exponential death rate of 2.8%. This corresponds closely to data for all canopy‐level trees in 18 forest inventory plots, each of 0.5 ha, for a mostly‐overlapping 2‐year period (2.8% per year). This study shows that high‐spatial‐resolution satellite data can now be used to measure old‐growth tropical rain forest tree death rates, suggesting many new avenues for tropical forest ecology and global change research.