bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regional heterogeneity in the haemodynamic responses to urotensin II infusion in relation to UT receptor localisation
Authors: Gardiner Sheila M , March Julie E , Kemp Philip A , Maguire Janet J , Kuc Rhoda E , Davenport Anthony P , Bennett Terence 
Published: November 2005

The aim of the study was to measure regional haemodynamic responses to 6 h infusions of human urotensin II (hUII), to identify possible mediators of the effects observed, and to relate the findings to the distribution of urotensin II receptors (UT receptors).
Male, Sprague–Dawley rats had pulsed Doppler flow probes and intravascular catheters implanted for measurement of regional haemodynamics in the conscious, freely moving state. Infusions of saline (0.4 ml h−1) or hUII (30, 300 and 3000 pmol kg−1 h−1) were given i.v. for 6 h, and the effects of pretreatment with indomethacin (5 mg kg−1 h−1), NG‐nitro‐L‐arginine methyl ester (L‐NAME, 3 mg kg−1 h−1) or propranolol (1 mg kg−1; 0.5 mg kg−1 h−1) on responses to hUII (300 pmol kg−1 h−1 for 6 h) were assessed. Cellular localisation of UT receptor‐like immunoreactivity was determined in relevant tissues.
hUII caused dose‐dependent tachycardia and hindquarters vasodilatation, accompanied by a slowly developing rise in blood pressure. Haemodynamic effects of hUII were attenuated by propranolol or L‐NAME and abolished by indomethacin. UT receptor‐like immunoreactivity was detected in skeletal and vascular smooth muscle.
The findings indicate that in conscious rats, infusions of hUII cause vasodilatation, which, of the vascular beds monitored, is selective for the hindquarters and dependent on cyclooxygenase products and nitric oxide. The pressor effect of hUII under these conditions is likely to be due to an increase in cardiac output, possibly due to a positive inotropic effect. UT receptor‐like immunoreactivity present in skeletal muscle is consistent with the haemodynamic pattern.

British Journal of Pharmacology (2006) 147, 612–621. doi:10.1038/sj.bjp.0706503
Reduction of experimental colitis in the rat by inhibitors of glycogen synthase kinase‐3β
Authors: Whittle Brendan J R , Varga Csaba , Pósa Anikó , Molnár Andor , Collin Marika , Thiemermann Christoph 
Published: November 2005

The effects of the inhibitors of glycogen synthase kinase‐3β (GSK‐3β), TDZD‐8 and SB 415286, which can substantially reduce the systemic inflammation associated with endotoxic shock in vivo, have now been investigated on the acute colitis provoked by trinitrobenzene sulphonic acid (TNBS) in the rat.
Administration of the GSK‐3β inhibitor TDZD‐8 (0.1, 0.33 or 1.0 mg kg−1, s.c., b.i.d., for 3 days) caused a dose‐dependent reduction in the colonic inflammation induced by intracolonic TNBS assessed after 3 days, both as the area of macroscopic involvement and as a score using 0–10 scale.
Likewise, following administration of the GSK‐3β inhibitor SB 415286 (0.1, 0.33 or 1.0 mg kg−1, s.c., b.i.d., for 3 days), the extent and degree of the TNBS‐provoked colonic inflammation was reduced.
Administration of either TDZD‐8 or SB 415286 reduced the fall in body weight following challenge with TNBS at each dose level studied.
The increase in myeloperoxidase activity, an index of neutrophil infiltration into the TNBS‐induced inflamed colon, was significantly inhibited by both TDZD‐8 and SB 415286 at each dose level.
The increase in the levels of the proinflammatory cytokine, TNF‐α, in the inflamed colon was also significantly inhibited by either compound at the highest doses evaluated.
The elevated levels of the transcription factor NF‐κB subunit p65, as determined by Western blot in the nuclear extracts from the TNBS‐provoked inflamed colonic tissue, were dose‐dependently reduced by TDZD‐8 or SB 415286 treatment.
These findings demonstrate that two chemically distinct selective inhibitors of the activity of GSK‐3β reduce the inflammation and tissue injury in a rat model of acute colitis. The mechanisms underlying this anti‐inflammatory action may be related to downregulation of NF‐κB activity, involved in the generation of proinflammatory mediators.

British Journal of Pharmacology (2006) 147, 575–582. doi:10.1038/sj.bjp.0706509
‘Coarse-to-Fine’ Cyclopean Processing
Authors: Popple Ariella V , Findlay John M 
Published: November 2005

Previously (Popple et al, 1998 Vision Research38 319–326) we found, using random-dot stereograms, that initial vergence increases with the size of a cyclopean disc. A corresponding improvement in stereoacuity within the disc was predicted, because disparities in the disc would be brought closer to the plane of current fixation. In the present experiment, we looked at the effect of the spatial extent of a briefly presented (≤ 500 ms) cyclopean depth pedestal on stereoacuity thresholds. Observers were required to judge the depth of a small, 1.7 deg, central disc relative to a larger surrounding disc in a random-pattern stereogram. The larger disc was set, initially, at a pedestal disparity of ±24 min of arc against a fixation-plane surround. The size of the larger disc was varied from 2.6 to 8.0 deg. As predicted, stereoacuity thresholds fell significantly with increasing pedestal disc size. Next, the disparity of the pedestal disc was varied. When pedestal disparity was reduced to ±2.4 min of arc, a disparity too small to demand vergence, the size effect disappeared except when the pedestal boundary was within 30 min of arc of the test disc boundary. We argue from this result that the effect was largely due to vergence and not cyclopean integration alone. However, the effect of pedestal size was found to persist with stimuli too brief to permit vergence (≤ 100 ms) suggesting that factors other than vergence may also play a role.
From Elements to Perception: Local and Global Processing in Visual Neurons
Authors: Spillmann Lothar 
Published: November 2005

Gestalt psychologists in the early part of the century challenged psychophysical notions that perceptual phenomena can be understood from a punctate (atomistic) analysis of the elements present in the stimulus. Their ideas slowed later attempts to explain vision in terms of single-cell recordings from individual neurons. A rapprochement between Gestalt phenomenology and neurophysiology seemed unlikely when the first ECVP was held in Marburg, Germany, in 1978. Since that time, response properties of neurons have been discovered that invite an interpretation of visual phenomena (including illusions) in terms of neuronal processing by long-range interactions, as first proposed by Mach and Hering in the last century. This article traces a personal journey into the early days of neurophysiological vision research to illustrate the progress that has taken place from the first attempts to correlate single-cell responses with visual perceptions. Whereas initially the receptive-field properties of individual classes of cells—eg contrast, wavelength, orientation, motion, disparity, and spatial-frequency detectors—were used to account for relatively simple visual phenomena, nowadays complex perceptions are interpreted in terms of long-range interactions, involving many neurons. This change in paradigm from local to global processing was made possible by recent findings, in the cortex, on horizontal interactions and backward propagation (feedback loops) in addition to classical feedforward processing. These mechanisms are exemplified by studies of the tilt effect and tilt aftereffect, direction-specific motion adaptation, illusory contours, filling-in and fading, figure – ground segregation by orientation and motion contrast, and pop-out in dynamic visual-noise patterns. Major questions for future research and a discussion of their epistemological implications conclude the article.
Stereoselective disposition of fluoxetine and norfluoxetine during pregnancy and breast‐feeding
Authors: Kim John , Riggs K. Wayne , Misri Shaila , Kent Nancy , Oberlander Tim F. , Grunau Ruth E. , Fitzgerald Colleen , Rurak Dan W. 
Published: November 2005

AimsTo compare the disposition of fluoxetine and norfluoxetine enanantiomers in the mother, foetus and infant.MethodsBlood from pregnant women taking fluoxetine (n = 9), during pregnancy was sampled in the third trimester and at delivery (maternal and cord venous blood), and from the infants 48 h after delivery. The subset of these women who were breastfeeding, plus additional subjects recruited in the postpartum period, were studied further, and maternal and infant blood, and breast milk was sampled between 6 days and 11 months (n = 23). Drug and metabolite concentrations were measured using gas chromatography/mass spectrometry or liquid chromatography, tandem mass spectrometry.ResultsThere was a high correlation between maternal and foetal (cord blood) fluoxetine and norfluoxetine enantiomers (r2−0.9), the mean foetal/maternal ratios (95% confidence intervals) being 0.91 (0.61, 1.02) and 1.04 (0.93, 1.05), for fluoxetine and norfluoxetine, respectively. In 2 day old infants exposed to the drugin utero, the fluoxetine and norfluoxetine plasma concentrations were the same as in cord blood at delivery. Over the next 2 months, the plasma concentrations in the infants fell progressively. Stereoselective disposition of both the drug and metabolite in the mother, foetus, infant and breast milk was observed. The S : R ratios in the foetus and newborn (∼3) were significantly higher than in the serum (∼2) or breast milk (∼1.9) of the mothers, resulting in greater exposure of the foetus and infants to the biologically active enantiomers, particularly S‐norfluoxetine.ConclusionsFoetal and infant exposure to fluoxetine and norfluoxetine is enhanced by their stereoselective disposition in the mother, foetus, breast milk and infant. Increased exposure may also result from decreased metabolism of the drug in the foetus and neonate.
Lanthanide and trace element mobilization in a lateritic toposequence: inferences from the Kaya laterite in Burkina Faso
Authors: Dequincey O. , Chabaux F. , Leprun J.‐C. , Paquet H. , Clauer N. , Larque P. 
Published: November 2005

SummaryThe geochemical development of laterites, a very common superficial formation in the tropics, is still a matter of debate. To determine the main steps of their formation, and to interpret lateral geochemical variations often observed within laterites, we studied the Kaya ferricrete in northern Burkina Faso by analysing two profiles in contrasting topographic positions. We determined the mineralogy and the composition in major and trace elements of whole rocks and of < 0.2 µm granulometric fractions. The nature and proportion of relictual primary minerals and of secondary clays and Fe‐oxyhydroxides control the distribution of major and soluble trace elements. The distribution patterns of Fe, transition metals, lanthanides, U and Th in the two profiles require (i) an initial accumulation in the top ferruginous horizon during its formation and (ii) a secondary redistribution downwards in the underlying horizons. Lanthanides, Ni and Co were remobilized to a much greater extent than Cu and Sc, whereas Fe, V, Cr and Th accumulated in the ferruginous horizon. The uphill better drained profile showed more intense redistribution than the downhill profile. Uranium in particular is poorly redistributed in the downhill profile, whereas it was redistributed like the lanthanides in the uphill profile. Remobilizations are also more intensely recorded in the fine fractions than in the whole rocks. These results allow us to propose a scenario for the formation of the Kaya laterite that accounts for both vertical and lateral chemical distributions. They also highlight the potential of multimethod geochemical studies to uncover the sequence of evolution of weathering profiles.
Niche‐based modelling as a tool for predicting the risk of alien plant invasions at a global scale
Authors: THUILLER WILFRIED , RICHARDSON DAVID M. , PYŠEK PETR , MIDGLEY GUY F. , HUGHES GREG O. , ROUGET MATHIEU 
Published: November 2005

AbstractPredicting the probability of successful establishment of plant species by matching climatic variables has considerable potential for incorporation in early warning systems for the management of biological invasions. We select South Africa as a model source area of invasions worldwide because it is an important exporter of plant species to other parts of the world because of the huge international demand for indigenous flora from this biodiversity hotspot. We first mapped the five ecoregions that occur both in South Africa and other parts of the world, but the very coarse definition of the ecoregions led to unreliable results in terms of predicting invasible areas. We then determined the bioclimatic features of South Africa's major terrestrial biomes and projected the potential distribution of analogous areas throughout the world. This approach is much more powerful, but depends strongly on how particular biomes are defined in donor countries. Finally, we developed bioclimatic niche models for 96 plant taxa (species and subspecies) endemic to South Africa and invasive elsewhere, and projected these globally after successfully evaluating model projections specifically for three well‐known invasive species (Carpobrotus edulis, Senecio glastifolius, Vellereophyton dealbatum) in different target areas. Cumulative probabilities of climatic suitability show that high‐risk regions are spatially limited globally but that these closely match hotspots of plant biodiversity. These probabilities are significantly correlated with the number of recorded invasive species from South Africa in natural areas, emphasizing the pivotal role of climate in defining invasion potential. Accounting for potential transfer vectors (trade and tourism) significantly adds to the explanatory power of climate suitability as an index of invasibility.The close match that we found between the climatic component of the ecological habitat suitability and the current pattern of occurrence of South Africa alien species in other parts of the world is encouraging. If species' distribution data in the donor country are available, climatic niche modelling offers a powerful tool for efficient and unbiased first‐step screening. Given that eradication of an established invasive species is extremely difficult and expensive, areas identified as potential new sites should be monitored and quarantine measures should be adopted.
Partitioning sources of soil‐respired CO2 and their seasonal variation using a unique radiocarbon tracer
Authors: CISNEROS‐DOZAL LUZ MARIA , TRUMBORE SUSAN , HANSON PAUL J. 
Published: November 2005

AbstractSoil respiration is derived from heterotrophic (decomposition of soil organic matter) and autotrophic (root/rhizosphere respiration) sources, but there is considerable uncertainty about what factors control variations in their relative contributions in space and time. We took advantage of a unique whole‐ecosystem radiocarbon label in a temperate forest to partition soil respiration into three sources: (1) recently photosynthesized carbon (C), which dominates root and rhizosphere respiration; (2) leaf litter decomposition and (3) decomposition of root litter and soil organic matter >1–2 years old.Heterotrophic sources and specifically leaf litter decomposition were large contributors to total soil respiration during the growing season. Relative contributions from leaf litter decomposition ranged from a low of ∼1±3% of total soil respiration (6± 3 mg C m−2 h−1) when leaf litter was extremely dry, to a high of 42±16% (96± 38 mg C m−2 h−1). Total soil respiration fluxes varied with the strength of the leaf litter decomposition source, indicating that moisture‐dependent changes in litter decomposition drive variability in total soil respiration fluxes. In the surface mineral soil layer, decomposition of C fixed in the original labeling event (3–5 years earlier) dominated the isotopic signature of heterotrophic respiration.Root/rhizosphere respiration accounted for 16±10% to 64±22% of total soil respiration, with highest relative contributions coinciding with low overall soil respiration fluxes. In contrast to leaf litter decomposition, root respiration fluxes did not exhibit marked temporal variation ranging from 34±14 to 40±16 mg C m−2 h−1 at different times in the growing season with a single exception (88±35 mg C m−2 h−1). Radiocarbon signatures of root respired CO2 changed markedly between early and late spring (March vs. May), suggesting a switch from stored nonstructural carbohydrate sources to more recent photosynthetic products.
Climatic and ecological determinants of leaf lifespan in polar forests of the high CO2 Cretaceous ‘greenhouse’ world
Authors: BRENTNALL S. J. , BEERLING D. J. , OSBORNE C. P. , HARLAND M. , FRANCIS J. E. , VALDES P. J. , WITTIG V. E. 
Published: November 2005

AbstractPolar forests once extended across the high‐latitude landmasses during ice‐free ‘greenhouse’ intervals in Earth history. In the Cretaceous ‘greenhouse’ world, Arctic conifer forests were considered predominantly deciduous, while those on Antarctica contained a significantly greater proportion of evergreens. To investigate the causes of this distinctive biogeographical pattern, we developed a coupled model of conifer growth, soil biogeochemistry and forest dynamics. Our approach emphasized general relationships between leaf lifespan (LL) and function, and incorporated the feedback of LL on soil nutrient status. The model was forced with a mid‐Cretaceous ‘greenhouse’ climate simulated by the Hadley Centre GCM. Simulated polar forests contained mixtures of dominant LLs, which reproduced observed biogeographical patterns of deciduous, mixed and evergreen biomes. It emerged that disturbance by fire was a critical factor. Frequent fires in simulated Arctic ecosystems promoted the dominance of trees with short LLs that were characterized by the rapid growth and colonization rates typical of today's boreal pioneer species. In Antarctica, however, infrequent fires allowed trees with longer LLs to dominate because they attained greater height, despite slower growth rates. A direct test of the approach was successfully achieved by comparing modelled LLs with quantitative estimates using Cretaceous fossil woods from Svalbard in the European Arctic and Alexander Island, Antarctica. Observations and the model both revealed mixed Arctic and evergreen Antarctic communities with peak dominance of trees with the same LLs. Our study represents a significant departure from the long‐held belief that leaf habit was an adaptation to warm, dark winter climates, and highlights a previously unrecognized role for disturbance (in whatever guise) in polar forest ecology.
Soil organic carbon changes in landscape units of Belgium between 1960 and 2000 with reference to 1990
Authors: LETTENS SUZANNA , VAN ORSHOVEN JOS , VAN WESEMAEL BAS , MUYS BART , PERRIN DOMINIQUE 
Published: November 2005

AbstractThe present study quantifies changes in soil organic carbon (SOC) stocks in Belgium between 1960, 1990 and 2000 for 289 spatially explicit land units with unique soil association and land‐use type, termed landscape units (LSU). The SOC stocks are derived from multiple nonstandardized sets of field measurements up to a depth of 30 cm.Approximately half of the LSU show an increase in SOC between 1960 and 2000. The significant increases occur mainly in soils of grassland LSU in northern Belgium. Significant decreases are observed on loamy cropland soils. Although the largest SOC gains are observed for LSU under forest (22 t C ha−1 for coniferous and 29 t C ha−1 for broadleaf and mixed forest in the upper 30 cm of soil), significant changes are rare because of large variability. Because the number of available measurements is very high for agricultural land, most significant changes occur under cropland and grassland, but the corresponding average SOC change is smaller than for forests (9 t C ha−1 increase for grassland and 1 t C ha−1 decrease for cropland).The 1990 data for agricultural LSU show that the SOC changes between 1960 and 2000 are not linear. Most agricultural LSU show a higher SOC stock in 1990 than in 2000, especially in northern Belgium. The observed temporal and spatial patterns can be explained by a change in manure application intensity.SOC stock changes caused by land‐use change are estimated. The SOC change over time is derived from observed differences between SOC stocks in space. Because SOC stocks are continuously influenced by a number of external factors, mainly land‐use history and current land management and climate, this approach gives only an approximate estimate whose validity is limited to these conditions.
Elevated atmospheric carbon dioxide increases soil carbon
Authors: JASTROW JULIE D. , MICHAEL MILLER R. , MATAMALA ROSER , NORBY RICHARD J. , BOUTTON THOMAS W. , RICE CHARLES W. , OWENSBY CLENTON E. 
Published: November 2005

AbstractThe general lack of significant changes in mineral soil C stocks during CO2‐enrichment experiments has cast doubt on predictions that increased soil C can partially offset rising atmospheric CO2 concentrations. Here, we show, through meta‐analysis techniques, that these experiments collectively exhibited a 5.6% increase in soil C over 2–9 years, at a median rate of 19 g C m−2 yr−1. We also measured C accrual in deciduous forest and grassland soils, at rates exceeding 40 g C m−2 yr−1 for 5–8 years, because both systems responded to CO2 enrichment with large increases in root production. Even though native C stocks were relatively large, over half of the accrued C at both sites was incorporated into microaggregates, which protect C and increase its longevity. Our data, in combination with the meta‐analysis, demonstrate the potential for mineral soils in diverse temperate ecosystems to store additional C in response to CO2 enrichment.
HER‐2/neu gene amplification in ovarian tumours: a comprehensive immunohistochemical and FISH analysis on tissue microarrays
Authors: Mayr D , Kanitz V , Amann G , Engel J , Burges A , Löhrs U , Diebold J 
Published: November 2005

Aims : Data on HER‐2/neu overexpression, its correlation to prognosis and the success of treatment with Herceptin® in ovarian carcinomas are scarce and contradictory. Therefore we assessed HER‐2/neu expression and amplification in a large series of ovarian tumours by using tissue microarrays (TMAs).Methods and results : Two TMAs containing 173 invasive carcinomas, 36 borderline tumours, 20 granulosa cell tumours, 14 carcinosarcomas, 11 benign cystadenoms and eight other pelvic tumours were constructed to assess HER‐2/neu gene amplification by fluorescence in‐situ hybridization (FISH) and immunohistochemistry. Immunohistochemistry was successful in 94.3%; 81.8% were HercepTestTM negative, 11.3% were scored as 1+, 4.1% as 2+ and 2.8% as 3+, including 3.1% of invasive carcinomas, 2.8% of borderline tumours and 7.7% of carcinosarcomas; 83.6% could be analysed successfully by FISH revealing no aberration in 75.8%, low amplification in 2.7% and high amplification in 3.7% of the cases. In 17.8% monosomy, trisomy, polysomy or deletion could be detected. All cases with high‐level amplification had 2+ or 3+ scores on immunohistochemistry.Conclusions : TMA is a feasible tool to study a large number of ovarian cases. Correlation between immunohistochemistry and FISH was excellent. HER‐2/neu overexpression or gene amplification does not correlate with histological tumour type, stage, grade or prognosis.