bluuebunny/crossref_metadata_2025 huggingface dataset:
Camellia japonica suppresses immunoglobulin E‐mediated allergic response by the inhibition of Syk kinase activation in mast cells
Authors: Lee J‐H. , Kim J‐W. , Ko N‐Y. , Mun S‐H. , Kim D‐K. , Kim J‐D. , Kim H‐S. , Lee K‐R. , Kim Y‐K. , Radinger M. , Her E. , Choi W‐S.
Published: February 2008

Background
Novel approaches are being explored to develop new therapies for various allergic diseases. Complementary and alternative medicines are considered to be promising avenues for the development of such new therapies.

Objectives
To investigate the effect of many Korean plants on the IgE‐mediated allergic response in mast cells and in vivo, and its mechanism of action.

Materials and methods
The anti‐allergic activity was tested by evaluating effects on degranulation of mast cells in culture and passive cutaneous anaphylaxis (PCA) in vivo. Its mechanism of action was investigated by immunoblotting analysis, immunoprecipitation, RT‐PCR, and other molecular biological approaches in mast cells.

Results
We screened approximately 100 natural plant extracts collected in Korea for in vitro anti‐allergic activity. The leaf extract of Camellia japonica (LECJ) exhibited the most potent effect on degranulation in antigen‐stimulated rodent and human mast cells. LECJ reversibly inhibited degranulation in a dose‐dependent manner, with IC50 values of ∼50 μg/mL for the mast cells, and it also suppressed the expression and secretion of TNF‐α and IL‐4 in rat basophilic leukaemia‐2H3 mast cells. In agreement with its in vitro activity, LECJ significantly inhibited mast cell‐mediated PCA in an animal model. LECJ inhibited activating phosphorylation of tyrosine Y371 on Syk kinase, indicating that LECJ inhibits the activity of Src‐family kinases in mast cells. In the in vitro kinase assay, LECJ directly inhibited Lyn kinase, the major Src‐family kinase in the cells. It also suppressed Akt and MAP kinases, which are critical for the production of various pro‐inflammatory cytokines in mast cells. In high‐performance liquid chromatography analysis, quercetin‐3‐β‐d‐glucoside and eugenol were identified as the major active components.

Conclusion
The present results strongly suggest that the anti‐allergic activity of LECJ is mediated through inhibiting degranulation and allergic cytokine secretion by inhibition of Src‐family kinase in mast cells and it may be useful for the treatment of mast cell‐related immediate and delayed allergic diseases.
Post‐allergen challenge inhibition of poly(ADP‐ribose) polymerase harbors therapeutic potential for treatment of allergic airway inflammation
Authors: Naura A. S. , Hans C. P. , Zerfaoui M. , You D. , Cormier S. A. , Oumouna M. , Boulares A. H.
Published: February 2008

Background
Identifying therapeutic drugs that block the release or effects of T‐helper type 2 (Th2) cytokines after allergen exposure is an important goal for the treatment of allergic inflammatory diseases including asthma. We recently showed, using a murine model of allergic airway inflammation, that poly(ADP‐ribose) polymerase (PARP) plays an important role in the pathogenesis of asthma‐related lung inflammation. PARP inhibition, by single injection of a novel inhibitor, thieno[2,3‐c]isoquinolin‐5‐one (TIQ‐A), before ovalbumin (OVA) challenge, prevented airway eosinophilia in C57BL/6 mice with concomitant suppression of Th2 cytokine production and mucus secretion.

Objective
To evaluate the efficacy of the drug when it is given after OVA challenge for its possible therapeutic potential.

Methods
This study was conducted using a murine model of allergic airway inflammation.

Results
A single injection of TIQ‐A (6 mg/kg) one or 6 h post‐allergen challenge conferred similar reduction in OVA challenge‐induced eosinophilia. More significantly, post‐allergen challenge administration of the drug exerted even better suppression on the production of IL‐4, IL‐5, IL‐13, and IgE and prevented airway hyperresponsiveness to inhaled‐methacholine. The significant decrease in IL‐13 was accompanied by a complete absence of airways mucus production indicating a potential protection against allergen‐induced airway remodelling.

Conclusion
The coincidence of the inflammation trigger and the time of drug administration appear to be important for the drug's more pronounced protection. The observed time window for efficacy, 1 or 6 h after allergen challenge may be of great clinical interest. These findings may provide a novel therapeutic strategy for the treatment of allergic airway inflammation, including asthma.
The impact of fasting and treatment omission on susceptibility to hypoglycaemia in children and adolescents with GH and cortisol insufficiency
Authors: Johnstone Helen C. , McNally Richard J. Q. , Cheetham Tim D.
Published: February 2008

Objective  Hypoglycaemia may be a frequent occurrence in young GH deficient patients and so we studied the response to fasting in children and adolescents with GH and/or cortisol deficiency.

Methods  A total of 20 patients (2–18 years) fasted for 14 h (22·00–12·00 h) on two occasions as part of a randomized cross‐over study. Fourteen had pituitary hormone deficiency (PHD) including GH deficiency (GHD). Of the 14 patients, seven were ACTH sufficient (PHDC+) and seven ACTH deficient (PHDC–). Six had primary adrenal failure (PAF). Subjects administered or omitted their normal dose of evening GH and/or morning hydrocortisone. Glucose, insulin, GH, cortisol, ketones and catecholamines were measured at 04·00 h and regularly from 07·00 to 12·00 h. Insulin sensitivity was assessed by HOMA and hypoglycaemia defined as a blood glucose (BG) ≤ 3·3 mmol/l.

Results  BG was related to age and body mass index on treatment but no subject became hypoglycaemic on or off therapy prior to 07·00 h. Five children (aged 3, 4, 7, 8 and 11 years) were hypoglycaemic between 07·00 and 12·00 h off treatment. There was a positive relationship between GH AUC and minimum BG in patients with PHD on treatment (r2 = 0·45, P = 0·012) with increased insulin sensitivity off treatment. Increased cortisol levels were seen in PHDC+ patients off GH (P < 0·001). A negative relationship was observed between minimum BG and adrenaline (r2 = 0·37, P = 0·01), ketone bodies (r2 = –0·20, P = 0·05) and NEFA (r2 = –0·35, P = 0·02). Noradrenaline levels were reduced in patients with PHDC–. Low BMI (on treatment) and young age (off treatment) were determinants of low BG levels in a multiple regression model.

Conclusions  Unrecognized overnight hypoglycaemia in children and adolescents on pituitary hormone replacement is uncommon but BG levels quickly become abnormal when treatment and meals are omitted. The insulin antagonistic actions of GH are important in preventing hypoglycaemia. Patients with PHD have altered sympathetic nerve activity.
Haploinsufficiency at GCK gene is not a frequent event in MODY2 patients
Authors: Garin Intza , Rica Itxaso , Estalella Itziar , Oyarzabal Mirentxu , Rodríguez‐Rigual Mercedes , Pedro Jose Ignacio San , Pérez‐Nanclares Gustavo , Fernández‐Rebollo Eduardo , Busturia Maria Angeles , Castaño Luis , De Nanclares Guiomar Pérez ,   Spanish MODY Group
Published: February 2008

Objective  The aim of this study was to characterize glucokinase (GCK) alterations in maturity‐onset diabetes of the young 2 (MODY2)‐suspected patients and to investigate their clinical characteristics in relation to the parental origin of the mutation.

Patients and methods  We studied a group of 57 unrelated Spanish patients presenting with MODY2 phenotype. Patients without mutation in the coding region of the GCK gene were screened for rearrangements by Multiplex Ligation‐dependent Probe Amplification (MLPA). After classification according to the parental origin of the mutation, clinical characteristics were compared between the groups.

Results  We detected a point mutation or small deletion or insertion of the GCK gene in 47 patients (82·5%); 19 mutations were novel. In addition, we found a whole‐gene deletion by MLPA. Patients carrying a GCK gene defect and those with MODY of unknown genetic origin shows similar phenotypes.

Comparison of clinical parameters according to the origin of the mutation did not show any differences in the birth weight (BW) nor in age at diagnosis. Patients who inherited the mutation from the father had higher fasting glucose levels at diagnosis.

Conclusion  Although the presence of haploinsufficiency of GCK is not a common cause of MODY2, gene dose analysis should be performed when no mutation is found.

Strict maternal euglycaemia can contribute to intrauterine growth restriction and low BW when the foetus has inherited the GCK mutation from the mother. As foetal genotype in generally is not known, serial foetal abdominal scans may act as a surrogate for this.
Difference in development of medullary thyroid carcinoma among carriers of RET mutations in codons 790 and 791*
Authors: Frank‐Raue Karin , Machens Andreas , Scheuba Christian , Niederle Bruno , Dralle Henning , Raue Friedhelm ,   the German MEN2 Study Group
Published: February 2008

Objectives  Hereditary medullary thyroid carcinoma (MTC) is caused by germ‐line mutations in the RET proto‐oncogene. Our study addresses the difference in development of MTC between rare mutations in RET codons 790, 791 and 804.

Design  We evaluated tumour stage, calcitonin levels, biochemical cure rates and associated endocrinopathies in 153 German/Austrian patients with RET 790 (n = 47), 791 (n = 56) and 804 mutations (n = 50), divided into index‐ and screening groups.

Results  Age at diagnosis in index‐patients did not differ significantly among the three codon groups (medians of 57, 61 and 53 years). Tumour stage at diagnosis was significantly less advanced with codon 791 (n = 22) than 790 (n = 16) and 804 (n = 16) mutations (P = 0·001). In screening patients, age at diagnosis did not differ significantly among the three groups (medians 19, 24 and 32 years). Tumour stage at diagnosis was also significantly less advanced with codon 791 (n = 34) than 790 (n = 31) and 804 (n = 34) (P = 0·032). Preoperative basal calcitonin levels were significantly lower in codon 791 carriers compared to codon 790 carriers, and cure rates were significantly higher in both index (75%vs. 31%; P = 0·03) and screening patients (100%vs. 75%; P = 0·015). Additional endocrinopathies were observed only with codon 791 carriers (four pheochromocytomas and two hyperparathyroidism).

Conclusion  There is a significant difference in MTC development with less extensive C‐cell disease, higher cure rate and more frequent additional endocrinopathies in carriers of RET codon 791 mutations compared with carriers of codons 790 and 804 mutations. This information should be considered when age of prophylactic thyroidectomy is discussed.
Host plant variation in plant‐mediated indirect effects: moth boring‐induced susceptibility of willows to a specialist leaf beetle
Authors: UTSUMI SHUNSUKE , OHGUSHI TAKAYUKI
Published: February 2008

Abstract 1. We examined the plant‐mediated indirect effects of the stem‐boring moth Endoclita excrescens (Lepidoptera: Hepialidae) on the leaf beetle Plagiodera versicolora (Coleoptera: Chrysomelidae) in three willow species, Salix gilgiana, S. eriocarpa, and S. serissaefolia.

2. When the stem‐boring moth larvae damaged stems in the previous year, willows were stimulated to produce vigorously growing lateral shoots on these stems. These new lateral shoots were significantly longer and the upper leaves had significantly higher nitrogen and water content than current‐year shoots on unbored stems, although the carbon content and leaf dry mass were not different between lateral and current‐year shoots.

3. In the field, leaf beetle larvae and adults had significantly greater densities on lateral shoots of bored stems than on current‐year shoots of unbored stems. A laboratory experiment showed that female beetles had significantly greater mass and fecundity when fed on leaves of newly‐emerged lateral shoots. Thus, the stem‐boring moth had a positive effect on the temporally and spatially separated leaf beetle by increasing resource availability by inducing compensatory regrowth.

4. The strength of the indirect effects on the density and performance of the leaf beetle differed among willow species, because there was interspecific variation in host quality and herbivore‐induced changes in plant traits. In particular, we suggest that the differences in magnitude of the changes among willow species in shoot length and leaf nitrogen content greatly affected the strength of the plant‐regrowth mediated indirect effect, coupled with host‐plant preference of the leaf beetle.
Co‐inheritance of a PKD1 mutation and homozygous PKD2 variant: a potential modifier in autosomal dominant polycystic kidney disease
Authors: Dedoussis G. V. Z. , Luo Y. , Starremans P. , Rossetti S. , Ramos A. J. , Cantiello H. F. , Katsareli E. , Ziroyannis P. , Lamnissou K. , Harris P. C. , Zhou J.
Published: February 2008

Background  Autosomal dominant polycystic kidney disease (ADPKD), which is caused by mutations in polycystins 1 (PC1) and 2 (PC2), is one of the most commonly inherited renal diseases, affecting ~1 : 1000 Caucasians.

Materials and methods  We screened Greek ADPKD patients with the denaturing gradient gel electrophoresis (DGGE) assay and direct sequencing.

Results  We identified a patient homozygous for a nucleotide change c.1445T > G, resulting in a novel homozygous substitution of the non‐polar hydrophobic phenylalanine to the polar hydrophilic cysteine in exon 6 at codon 482 (p.F482C) of the PKD2 gene and a de‐novo PKD1 splice‐site variant IVS21–2delAG. We did not find this PKD2 variant in a screen of 280 chromosomes of healthy subjects, supporting its pathogenicity. The proband's parents did not have the PKD1 mutation. Real‐time PCR of the PKD2 transcript from a skin biopsy revealed 20‐fold higher expression in the patient than in a healthy subject and was higher in the patient's peripheral blood mononuclear cells (PBMCs) than in those of her heterozygote daughter and a healthy subject. The greater gene expression was also supported by Western blotting. Inner medullar collecting duct (IMCD) cells transfected with the mutant PKD2 mouse gene presented a perinuclear and diffuse cytoplasmic localization compared with the wild type ER localization. Patch‐clamping of PBMCs from the p.F482C homozygous and heterozygous subjects revealed lower polycystin‐2 channel function than in controls.

Conclusions  We report for the first time a patient with ADPKD who is heterozygous for a de novo PKD1 variant and homozygous for a novel PKD2 mutation.
Elevation of matrix metalloproteinases and interleukin‐6 in the culprit coronary artery of myocardial infarction
Authors: Suzuki H. , Kusuyama T. , Sato R. , Yokota Y. , Tsunoda F. , Sato T. , Shoji M. , Iso Y. , Koba S. , Katagiri T.
Published: February 2008

Background  Interleukin‐6 (IL‐6) and metalloproteinases (MMPs) are involved in the instability of vulnerable plaque associated with the induction of acute myocardial infarction (AMI). We examined the regional changes of cytokines, MMPs and adhesion molecules in patients with AMI to elucidate how these factors are involved in the onset of AMI.

Materials and methods  One hundred and twenty‐two patients with AMI were included. Blood was aspirated from the culprit coronary artery with a thrombectomy catheter, and was also sampled from peripheral veins during the coronary intervention. Control samples were obtained from the peripheral blood of age‐matched patients.

Results  The serum levels of IL‐6 (P < 0·05), tumour necrosis factor‐α (P < 0·005), MMP‐1 (P < 0·001), MMP‐13 (P < 0·001), soluble intercellular adhesion molecule‐1 (P < 0·005), and soluble vascular cellular adhesion molecule‐1 (P < 0·05) in peripheral blood were significantly higher in the AMI group than in the controls. Aspirated serum contained significantly higher levels of IL‐6 (P < 0·001), MMP‐1 (P < 0·001), and MMP‐13 (P < 0·05) compared to the peripheral blood of AMI. Serum IL‐6 levels were significantly higher in the aspirated than in the peripheral blood in the patients hospitalized within 6 h and 6–12 h, but were similar in the aspirated and peripheral blood of the patients hospitalized 12–24 h after the onset of AMI. There were no differences between the aspirated serum and peripheral blood in the levels of interleukin‐1β and MMP‐2.

Conclusions  The levels of MMP‐1, MMP‐13 and IL‐6 were higher in the culprit coronary artery than in the peripheral blood. These factors appear to be involved in the early stage of AMI.
Validation study of nasal nitric oxide measurements using a hand‐held electrochemical analyser
Authors: Maniscalco M. , Laurentiis G. de , Weitzberg E. , Lundberg J. O. , Sofia M.
Published: February 2008

Background  Exhaled nitric oxide (NO) measurement is a simple and non‐invasive method for monitoring airway inflammation. Similarly, nasal NO has been proposed as a surrogate marker in inflammatory diseases of the upper airways, e.g. allergic rhinitis. A new portable analyser using an electrochemical sensor has been developed for measurements of exhaled NO, and its reproducibility and comparison with other analysers has been tested recently in healthy subjects and in patients with lower airways disease. The application of this hand‐held analyser in nasal NO analysis was tested and compared to the gold standard represented by a chemiluminescence analyser.

Materials and methods  Thirty subjects including 15 patients with allergic rhinitis (AR) and 15 healthy subjects (HS) were studied. The intraindividual variability, calculated as the difference in nasal NO levels between two measurements from a single nasally exhaled breath manoeuvre, and the comparison between the electrochemical analyser (NIOX MINO, Aerocrine) and a chemiluminescence analyser (NOA, Sievers) were performed.

Results  In AR patients mean nasal NO was 59·0 ± 16·3 p.p.b. with the MINO and 58·3 ± 15·6 p.p.b. with the NOA. In HS nasal NO was 49·1 ± 10·8 p.p.b. with the MINO and 49·8 ± 8·2 p.p.b. with the NOA. The Bland‐Altman analysis showed bias values of 0·005 ± 3·6 with the 95% limits of agreement from –6·97 to 6·98 p.p.b.

Conclusion  Measurements of nasal NO levels with a hand‐held electrochemical analyser are reproducible and the results are comparable to a stationary chemiluminescence analyser.
Interactions of ferricyanide with humic soils and charred straw
Authors: Rennert T. , Kaufhold S. , Brodowski S. , Mansfeldt T.
Published: February 2008

The iron‐cyanide complexes ferricyanide, [FeIII(CN)6]3−, and ferrocyanide, [FeII(CN)6]4−, are anthropogenic contaminants in soil. We studied the interactions of ferricyanide with humic soils and charred straw (maize and rye, both charred at 300, 400 and 500°C) by batch experiments and Fourier transform infrared (FTIR) spectroscopy. All soil samples sorbed ferricyanide (up to 8.4 g kg−1). Precipitation of a manganese ferrocyanide after reduction of ferricyanide in the moderately acidic to neutral soils was deduced from both FTIR spectroscopy (CN absorption bands at 2069–2065 cm−1) and geochemical modelling. Ferricyanide was also adsorbed onto the charred straw. The amounts of iron‐cyanide complexes adsorbed increased with increasing charring temperature, with a maximum of 1.71 g kg−1. An absorption band at 2083 cm−1 indicated weakly adsorbed intermediates of the reduction of ferricyanide to ferrocyanide. This band disappeared in the samples charred at higher temperature, whereas a band at 2026 cm−1 was present in all spectra and became intensified in the high‐temperature straw. We attribute this band to ferrocyanide forming inner‐sphere complexes, presumably with quinone species of the organic matter. The band at 2026 cm−1 was also present in the spectra of the soils, indicating that soil organic matter also adsorbs ferrocyanide. However, in humic soils the main processes of ferricyanide interaction include reduction to ferrocyanide and precipitation as manganese ferrocyanide. Quantitatively, adsorption on highly aromatic substances plays only a less important role as compared with precipitation.
How do elevated CO2 and O3 affect the interception and utilization of radiation by a soybean canopy?
Authors: DERMODY ORLA , LONG STEPHEN P. , McCONNAUGHAY KELLY , DeLUCIA EVAN H.
Published: February 2008

Net productivity of vegetation is determined by the product of the efficiencies with which it intercepts light (ɛi) and converts that intercepted energy into biomass (ɛc). Elevated carbon dioxide (CO2) increases photosynthesis and leaf area index (LAI) of soybeans and thus may increase ɛi and ɛc; elevated O3 may have the opposite effect. Knowing if elevated CO2 and O3 differentially affect physiological more than structural components of the ecosystem may reveal how these elements of global change will ultimately alter productivity. The effects of elevated CO2 and O3 on an intact soybean ecosystem were examined with Soybean Free Air Concentration Enrichment (SoyFACE) technology where large field plots (20‐m diameter) were exposed to elevated CO2 (∼550 μmol mol−1) and elevated O3 (1.2 × ambient) in a factorial design. Aboveground biomass, LAI and light interception were measured during the growing seasons of 2002, 2003 and 2004 to calculate ɛi and ɛc. A 15% increase in yield (averaged over 3 years) under elevated CO2 was caused primarily by a 12% stimulation in ɛc , as ɛi increased by only 3%. Though accelerated canopy senescence under elevated O3 caused a 3% decrease in ɛi, the primary effect of O3 on biomass was through an 11% reduction in ɛc. When CO2 and O3 were elevated in combination, CO2 partially reduced the negative effects of elevated O3. Knowing that changes in productivity in elevated CO2 and O3 were influenced strongly by the efficiency of conversion of light energy into energy in plant biomass will aid in optimizing soybean yields in the future. Future modeling efforts that rely on ɛc for calculating regional and global plant productivity will need to accommodate the effects of global change on this important ecosystem attribute.
Potential effects of climate change on DOC release from three different soil types on the Northern Pennines UK: examination using field manipulation experiments
Authors: HARRISON ANTHONY F. , TAYLOR KENNETH , SCOTT ANDY , POSKITT JAN , BENHAM DAVID , GRACE JOHN , CHAPLOW JACKY , ROWLAND PHILIP
Published: February 2008

Three field manipulation experiments were carried out during 1993–1995 on the Northern Pennines to investigate the influences of temperature, solar radiation and rainfall on the release of dissolved organic carbon (DOC) from vegetated soil cores using zero‐tension lysimeters. The cores were manipulated by being translocated to four sites down a climatic gradient, by artificial soil heating or being exposed to double normal rainfall. In each experiment three soil types, a brown earth, a micropodzol and a peaty gley, with differing organic matter content and distribution within the profile, were studied. DOC data, expressed as mg C m−2 day−1, were analysed following log10 transformation, by a repeated measures analysis of variance procedure, using climatic variables measured concurrently with sampling, and 1 and 2 months before sampling. DOC release was dominated by rainfall but was also associated with solar radiation and temperature. With each of the three climatic variables, rainfall, solar radiation and temperature, both positive and negative effects on DOC release have been found significant, indicating that the concurrent and delayed effects of the same variable may be different. DOC release was positively related with all three soils to concurrent rainfall, indicating rainfall's primary leaching action. DOC release was also negatively related to rainfall of the previous month indicating that its action depletes the leachable pool of DOC in the soil. DOC release was positively associated with solar radiation 2 months earlier, indicating that DOC's main source is that of primary production; DOC peaks closely followed peaks of annual primary production. DOC release was linked with temperature, the strongest association being with temperature 2 months earlier, indicating that temperature effects both primary production and DOC regeneration via organic matter decomposition. A conceptual model, relating our findings to those processes known to govern DOC release from soils, has been presented.
Carbon dioxide exchange above a Mediterranean C3/C4 grassland during two climatologically contrasting years
Authors: AIRES LUIS MIGUEL IGREJA , PIO CASIMIRO ADRIÃO , PEREIRA JOÃO SANTOS
Published: February 2008

Eddy‐covariance measurements of net ecosystem carbon exchange (NEE) were carried out above a grazed Mediterranean C3/C4 grassland in southern Portugal, during two hydrological years, 2004–2005 and 2005–2006, of contrasting rainfall. Here, we examine the seasonal and interannual variation in NEE and its major components, gross primary production (GPP) and ecosystem respiration (Reco), in terms of the relevant biophysical controls. The first hydrological year was dry, with total precipitation 45% below the long‐term mean (669 mm) and the second was normal, with total precipitation only 12% above the long‐term mean. The drought conditions during the winter and early spring of the dry year limited grass production and the leaf area index (LAI) was very low. Hence, during the peak of the growth period, the maximum daily rate of NEE and the light‐use and water‐use efficiencies were approximately half of those observed in the normal year. In the summer of 2006, the warm‐season C4 grass, Cynodon dactylon L., exerted an evident positive effect on NEE by converting the ecosystem into a carbon sink after strong rain events and extending the carbon sequestration for several days, after the end of senescence of the C3 grasses. On an annual basis, the GPP and NEE were 524 and 49 g C m−2, respectively, for the dry year, and 1261 and −190 g C m−2 for the normal year. Therefore, the grassland was a moderate net source of carbon to the atmosphere, in the dry year, and a considerable net carbon sink, in the normal year. In these 2 years of experiment the total amount of precipitation was the main factor determining the interannual variation in NEE. In terms of relevant controls, GPP and NEE were strongly related to incident photosynthetic photon flux density on short‐term time scales. Changes in LAI explained 84% and 77% of the variation found in GPP and NEE, respectively. Variations in Reco were mainly controlled by canopy photosynthesis. After each grazing event, the reduction in LAI affected negatively the NEE.
Global change and biological soil crusts: effects of ultraviolet augmentation under altered precipitation regimes and nitrogen additions
Authors: BELNAP JAYNE , PHILLIPS SUSAN L. , FLINT STEPHAN , MONEY JOHN , CALDWELL MARTYN
Published: February 2008

Biological soil crusts (BSCs), a consortium of cyanobacteria, lichens, and mosses, are essential in most dryland ecosystems. As these organisms are relatively immobile and occur on the soil surface, they are exposed to high levels of ultraviolet (UV) radiation and atmospheric nitrogen (N) deposition, rising temperatures, and alterations in precipitation patterns. In this study, we applied treatments to three types of BSCs (early, medium, and late successional) over three time periods (spring, summer, and spring–fall). In the first year, we augmented UV and altered precipitation patterns, and in the second year, we augmented UV and N. In the first year, with average air temperatures, we saw little response to our treatments except quantum yield, which was reduced in dark BSCs during one of three sample times and in Collema BSCs two of three sample times. There was more response to UV augmentation the second year when air temperatures were above average. Declines were seen in 21% of the measured variables, including quantum yield, chlorophyll a, UV‐protective pigments, nitrogenase activity, and extracellular polysaccharides. N additions had some negative effects on light and dark BSCs, including the reduction of quantum yield, β‐carotene, nitrogenase activity, scytonemin, and xanthophylls. N addition had no effects on the Collema BSCs. When N was added to samples that had received augmented UV, there were only limited effects relative to samples that received UV without N. These results indicate that the negative effect of UV and altered precipitation on BSCs will be heightened as global temperatures increase, and that as their ability to produce UV‐protective pigments is compromised, physiological functioning will be impaired. N deposition will only ameliorate UV impacts in a limited number of cases. Overall, increases in UV will likely lead to lowered productivity and increased mortality in BSCs through time, which, in turn, will reduce their ability to contribute to the stability and fertility of soils in dryland regions.
Shrub encroachment in North American grasslands: shifts in growth form dominance rapidly alters control of ecosystem carbon inputs
Authors: KNAPP ALAN K. , BRIGGS JOHN M. , COLLINS SCOTT L. , ARCHER STEVEN R. , BRET‐HARTE M. SYNDONIA , EWERS BRENT E. , PETERS DEBRA P. , YOUNG DONALD R. , SHAVER GAIUS R. , PENDALL ELISE , CLEARY MEAGAN B.
Published: February 2008

Shrub encroachment into grass‐dominated biomes is occurring globally due to a variety of anthropogenic activities, but the consequences for carbon (C) inputs, storage and cycling remain unclear. We studied eight North American graminoid‐dominated ecosystems invaded by shrubs, from arctic tundra to Atlantic coastal dunes, to quantify patterns and controls of C inputs via aboveground net primary production (ANPP). Across a fourfold range in mean annual precipitation (MAP), a key regulator of ecosystem C input at the continental scale, shrub invasion decreased ANPP in xeric sites, but dramatically increased ANPP (>1000 g m−2) at high MAP, where shrub patches maintained extraordinarily high leaf area. Concurrently, the relationship between MAP and ANPP shifted from being nonlinear in grasslands to linear in shrublands. Thus, relatively abrupt (<50 years) shifts in growth form dominance, without changes in resource quantity, can fundamentally alter continental‐scale pattern of C inputs and their control by MAP in ways that exceed the direct effects of climate change alone.
Climate warming, dispersal inhibition and extinction risk
Authors: MASSOT MANUEL , CLOBERT JEAN , FERRIÈRE RÉGIS
Published: February 2008

Global warming impels species to track their shifting habitats or adapt to new conditions. Both processes are critically influenced by individual dispersal. In many animals, dispersal behaviour is plastic, but how organisms with plastic dispersal respond to climate change is basically unknown. Here, we report the analysis of interannual dispersal change from 16 years of monitoring a wild population of the common lizard, and a 12‐year manipulation of lizards' diet intended to disentangle the direct effect of temperature rise on dispersal from its effects on resource availability. We show that juvenile dispersal has declined dramatically over the last 16 years, paralleling the rise of spring temperatures during embryogenesis. A mesoscale model of metapopulation dynamics predicts that in general dispersal inhibition will elevate the extinction risk of metapopulations exposed to contrasting effects of climate warming.
Climate induced increases in species richness of marine fishes
Authors: HIDDINK J. G. , Ter HOFSTEDE R.
Published: February 2008

Climate change has been predicted to lead to changes in local and regional species richness through species extinctions and latitudinal ranges shifts. Here, we show that species richness of fish in the North Sea, a group of ecological and socio‐economical importance, has increased over a 22‐year period and that this rise is related to higher water temperatures. Over eight times more fish species displayed increased distribution ranges in the North Sea (mainly small‐sized species of southerly origin) compared with those whose range decreased (primarily large and northerly species). This increase in species richness can be explained from the fact that fish species richness in general decreases with latitude. This observation confirms that the interaction between large‐scale biogeographical patterns and climate change may lead to increasing species richness at temperate latitudes.
Declining coral calcification in massive Porites in two nearshore regions of the northern Great Barrier Reef
Authors: COOPER TIMOTHY F. , DE'ATH GLENN , FABRICIUS KATHARINA E. , LOUGH JANICE M.
Published: February 2008

Temporal and spatial variation in the growth parameters skeletal density, linear extension and calcification rate in massive Porites from two nearshore regions of the northern Great Barrier Reef (GBR) were examined over a 16‐year study period. Calcification rates in massive Porites have declined by approximately 21% in two regions on the GBR ∼450 km apart. This is a function primarily of a decrease in linear extension (∼16%) with a smaller decline in skeletal density (∼6%) and contrasts with previous studies on the environmental controls on growth of massive Porites on the GBR. Changes in the growth parameters were linear over time. Averaged across colonies, skeletal density declined over time from 1.32 g cm−3 (SE = 0.017) in 1988 to 1.25 g cm−3 (0.013) in 2003, equivalent to 0.36% yr−1 (0.13). Annual extension declined from 1.52 cm yr−1 (0.035) to 1.28 cm yr−1 (0.026), equivalent to 1.02% yr−1 (0.39). Calcification rates (the product of skeletal density and annual extension) declined from 1.96 g cm−2 yr−1 (0.049) to 1.59 g cm−2 yr−1 (0.041), equivalent to 1.29% yr−1 (0.30). Mean annual seawater temperatures had no effect on skeletal density, but a modal effect on annual extension and calcification with maxima at ∼26.7 °C. There were minor differences in the growth parameters between regions. A decline in coral calcification of this magnitude with increasing seawater temperatures is unprecedented in recent centuries based on analysis of growth records from long cores of massive Porites. We discuss the decline in calcification within the context of known environmental controls on coral growth. Although our findings are consistent with studies of the synergistic effect of elevated seawater temperatures and pCO2 on coral calcification, we conclude that further data on seawater chemistry of the GBR are required to better understand the links between environmental change and effects on coral growth.
Voltinism flexibility of a riverine dragonfly along thermal gradients
Authors: BRAUNE ERIK , RICHTER OTTO , SÖNDGERATH DAGMAR , SUHLING FRANK
Published: February 2008

Potential effects of future warming should be reflected in life history patterns of aquatic organisms observed in warmer climates or in habitats that are different in ambient temperature. In the special case of the dragonflyGomphus vulgatissimus(L.) (Odonata: Gomphidae) previous research suggests that voltinism decreases from south to north. We analysed data on voltinism from 11 sample sites along a latitudinal gradient from about 44°N to 53°N, comprising small streams to medium‐sized rivers. Furthermore, to simulate different conditions and to allow projections for future climate change scenarios, we developed a population dynamic model based on a projection matrix approach. The parameters of the model are dependent on temperature and day length. Our field results indicate a decrease in voltinism along the latitudinal gradient from southern to northern Europe and a corresponding increase of voltinism with higher temperatures. An increase in voltinism with width of the running water implies an effect of varying habitat temperature. Under the impact of global warming, our model predicts an increased development speed, particularly in the northern part of the latitudinal gradient, an extension of the northern range limit and changes in phenology ofG. vulgatissimus, leading to an extension of the flight season in certain regions along the gradient.
Disregarding topographical heterogeneity biases species turnover assessments based on bioclimatic models
Authors: LUOTO M. , HEIKKINEN R. K.
Published: February 2008

We investigated whether the inclusion of topographical heterogeneity in bioclimatic envelope models would significantly alter predictions of climate change – induced broad‐scale butterfly species range size changes in Europe. Using generalized additive models, and data on current climate and species distributions and two different climate scenarios (HadCM3A2 and HadCM3B2) for the period 2051–2080, we developed predictions of the currently suitable area and potential range size changes of 100 European butterfly species. The inclusion of elevation range increased the predictive accuracy of climate‐only models for 86 of the 100 species. The differences in projected future distributions were most notable in mountainous areas, where the climate–topography models projected only ca. half of the species losses than the climate‐only models. By contrast, climate–topography models estimated double the losses of species than climate‐only models in the flatlands regions. Our findings suggest that disregarding topographical heterogeneity may cause a significant source of error in broad‐scale bioclimatic modelling. Mountainous regions are likely to be even more important for future conservation of species than had until now been predicted, based on bioclimatic envelope models that did not take an explicit account of elevational range of grid squares.
Seasonal and annual variation of carbon exchange in an evergreen Mediterranean forest in southern France
Authors: ALLARD V. , OURCIVAL J. M. , RAMBAL S. , JOFFRE R. , ROCHETEAU A.
Published: February 2008

We present 9 years of eddy covariance measurements made over an evergreen Mediterranean forest in southern France. The goal of this study was to quantify the different components of the carbon (C) cycle, gross primary production (GPP) and ecosystem respiration (Reco), and to assess the effects of climatic variables on these fluxes and on the net ecosystem exchange of carbon dioxide. The Puéchabon forest acted as a net C sink of −254 g C m−2 yr−1, with a GPP of 1275 g C m−2 yr−1 and a Reco of 1021 g C m−2 yr−1. On average, 83% of the net annual C sink occurred between March and June. The effects of exceptional events such the insect‐induced partial canopy defoliation that occurred in spring 2005, and the spring droughts of 2005 and 2006 are discussed. A high interannual variability of ecosystem C fluxes during summer and autumn was observed but the resulting effect on the annual net C budget was moderate. Increased severity and/or duration of summer drought under climate change do not appear to have the potential to negatively impact the average C budget of this ecosystem. On the contrary, factors affecting ecosystem functioning (drought and/or defoliation) during March–June period may reduce dramatically the annual C balance of evergreen Mediterranean forests.
Worst experiences of pain and conceptions of worst pain imaginable among nursing students
Authors: Bergh Ingrid , Jakobsson Eva , Sjöström Björn
Published: February 2008

Title.  Worst experiences of pain and conceptions of worst pain imaginable among nursing students

Aim. This paper is a report of a study to explore nursing students’ own worst experiences of pain as well as their conceptions of the worst pain imaginable.

Background. Pain is a personal experience, often assessed using a visual analogue scale. The endpoints of this scale are labelled with the extremes for pain experience (e.g. no pain to worst pain imaginable). People may understand the meaning of ‘no pain’, but it is unclear what meaning they assign to ‘worst pain imaginable’. This indicates that a rating along the Visual Analogue Scale‐line is dependent on the individual’s previous experiences.

Methods. Data were collected during the autumn of 2002. In total, 549 nursing students completed a questionnaire focusing on two main questions: ‘What is the worst experience of hurt, ache or pain you have had?’ and ‘What is the worst pain imaginable for you?’ Content analysis was used for data analysis.

Results. The students’ worst experience of pain was mostly related to acute or traumatic painful conditions, pain associated with female physiology, inflicted pain, psychological suffering and chronic painful conditions. The worst pain imaginable was described as condition‐related pain, overwhelming pain, experiences of losses, deliberately inflicted pain, psychological suffering and as vicarious pain.

Conclusion. The findings imply that nursing students, when they are imagining pain, include dimensions such as hope of relief, grief, control over the situation, powerlessness and empathy for and suffer with other people’s pain. Further research is needed to explore why professional experience as a nurse diminishes the ability to imagine patients’ pain.
Embodied dispositions or experience? Identifying new patterns of professional competence
Authors: Rischel Vibeke , Larsen Kristian , Jackson Karen
Published: February 2008

Title.  Embodied dispositions or experience? Identifying new patterns of professional competence

Aim.  This paper is a report of a study to explore nurses’ competence as revealed during an admission assessment.

Background.  Studies of nursing competence and of models of competence have become virtually synonymous with the five‐stage developmental model applied to nursing by Benner. However, the model has been criticized for its interpretation of intuition and also for the exclusion of the social elements and context of nursing practice.

Method.  The study was conducted in 2004. This paper draws on data from 12 structured non‐participant observations of admission assessments in an orthopaedic ward by four nurses: two with <1 year’ experience and two with more than 5 years’ experience. Defined variables were observed using instantaneous and event sampling. The analysis was guided theoretically by the assumptions embedded in Benner’s competence model and Bourdieu’s theory of practice.

Findings.  Each nurse had unique patterns of practice that did not correspond to the level of competence expected in relation to their length of experience as a nurse. Nurses’ competence seems to be situational rather than related to levels in the developmental model: in some observed variables, inexperience nurses acted as experts, while experienced nurses acted as advanced beginners, contrary to the expectations of Benner.

Conclusion.  The five‐stage developmental competence model could not be verified empirically in this study. The findings suggest that further empirical research is needed to clarify the apparent links between situation and competence.
Parental stress and satisfaction in the non‐tertiary special care nursery
Authors: Foster Jann , Bidewell John , Buckmaster Adam , Lees Sylvia , Henderson‐Smart David
Published: February 2008

Title.  Parental stress and satisfaction in the non‐tertiary special care nursery

Aim.  This paper is a report of a study examining the effects of using headbox oxygen and continuous oxygen positive airway pressure treatments for respiratory distress on stress and satisfaction of parents with infants in a special care nursery, and the relationship between parental stress and satisfaction.

Background.  Continuous positive airway pressure respiratory support is increasingly used in special care nurseries worldwide. Almost nothing is known about effects of different types of respiratory support on the stress and satisfaction of parents with babies in the special care nursery.

Method.  Questionnaires were used from August 2004 to June 2006 in five special care nurseries to measure parental stress using an adaptation of the Parental Stressor Scale: Neonatal Intensive Care Unit and 5‐point scales to measure overall stress and satisfaction.

Findings.  Questionnaires were returned from 42 parents of babies receiving headbox oxygen and 51 parents of babies receiving continuous positive airway pressure (62% response rate). High stress was commonly reported. Stress did not differ statistically significantly between the two treatments. Parents with babies receiving continuous positive airway pressure were more satisfied compared to the headbox group. Stress and satisfaction were not statistically significantly correlated.

Conclusion.  Clinicians need not favour either method of respiratory support when attempting to minimize parental experience of environmental stress. Further research is needed to test parental stress reduction strategies in the special care nursery.
Concept clarification of neonatal neurobehavioural organization
Authors: Bell Aleeca F. , Lucas Ruth , White‐Traut Rosemary C.
Published: February 2008

Title. Concept clarification of neonatal neurobehavioural organization

Aim. This paper is a report of a concept analysis of neonatal neurobehavioural organization for healthy full‐term infants.

Background. The neonatal period is an opportune time for researchers and clinicians to assess and intervene for optimal neurobehavioural organization. Yet there is inconsistency and lack of clarity in a scientifically grounded definition of neonatal neurobehavioural organization. Clarification of the concept will strengthen research findings that influence practice for optimal infant development.

Method. A concept analysis of the literature between 1939 and 2007 (n = 57) was conducted using Penrod and Hupcey’s principle‐based concept analysis and Morse’s concept clarification.

Findings. The concept analysis within and across multiple disciplines revealed: (1) a view of the concept as a holistic phenomenon with multiple dimensions; (2) no agreement on the ideal instrument to operationally define the concept; and (3) consistency in implied meaning, but great variability in terminology. Neonatal neurobehavioural organization was defined as the ability of the neonate to use goal‐directed states of consciousness, in reciprocal interaction with the caregiving environment, to facilitate the emergence of differentiating, hierarchical, and coordinated neurobehavioural systems, with ever‐increasing resiliency and capacity to learn from complex stimuli.

Conclusion. A clear conceptual definition will help the international community to communicate effectively within and between disciplines and to apply evidence‐based research findings. It will encourage the development of valid and reliable instruments to capture the concept’s multiple dimensions and direct attention to the infant’s experience, which sculpts early neurobehavioural organization.