bluuebunny/crossref_metadata_2025 huggingface dataset:
Amino acid 15N in long‐term bare fallow soils: influence of annual N fertilizer and manure applications
Authors: Bol R. , Ostle N. J. , Petzke K. J. , Chenu C. , Balesdent J.
Published: February 2008

Long‐term dynamics of amino acids (AAs), from a bare fallow soil experiment (established in 1928 at INRA‐Versailles, France), were examined in unamended control (Con) plots and plots treated with ammonium sulphate (Amsul), ammonium nitrate (Amnit), sodium nitrate (Nanit) or with animal manure (Man). Topsoil (0–25 cm) from 1929, 1963 and 1997 was analysed for C, N and 15N content and distribution of 18 amino acids recovered after acid hydrolysis with 6 m HCl. With time, soil N, C and AA content were reduced in Con, Amsul, Amnit and Nanit, but increased in Man. However, the absolute N loss was 3–11 times larger in Man than Nanit, Amsul, Amnit and Con, due to the much higher N annual inputs applied to Man. From 1929 to 1997 in Con, Amsul, Amnit and Nanit the whole soil and non‐hydrolysable‐N pool δ15N increased associated with the loss of N (indicative of Rayleigh 15N/14N fractionation). No δ15N change from 1929 to 1997 was found in the hydrolysable AA‐N (HAN) pool. Fertilizer N inputs aided stabilization of soil AA‐N, as AA half‐life in the mineral N fertilizer treatments increased from 34 years in 1963 to 50 years in 1997. The δ15N values of alanine and leucine reflected both source input and 15N/14N fractionation effects in soils. The δ15N increase of ornithine (∼6‰) was similar to the whole soil. The δ15N change of phenylalanine in Con (decrease of 7‰) was related to its proportional loss since 1929, whereas for Amsul, Amnit, Nanit and Man it was associated with isotope effects caused by the fertilizer inputs. However, the soil δ15N value of most individual amino acids (IAAs) did not significantly change over nearly 70 years, even with mineral or organic N inputs. We conclude for these bare fallow systems that: (i) δ15N changes in the whole soil and non‐hydrolysable AA pool were solely driven by microbial processes and not by the nature of fertilizer inputs, and (ii) without plant inputs, the δ15N of the HAN pool and (most) IAAs may reflect the influence of plant–soil interactions from the previous (arable cropping) rather than present (fallow) land use on these soil δ15N values.
Terrestrial export of highly bioavailable carbon from small boreal catchments in spring floods
Authors: ÅGREN A. , BERGGREN M. , LAUDON H. , JANSSON M.
Published: February 2008

1. We assessed the terrestrial export of organic carbon, which effectively supported aquatic bacterial production (BP), from small boreal catchments during spring flood. We analysed stream runoff from nine small catchments with different proportions of peat mires and coniferous forests by monitoring the dissolved organic carbon (DOC) flux in combination with conducting bacterial bioassays.

2. Multiple linear regression analysis showed that BP during 7‐day‐dark bioassays (BP7; μg C L−1day−1) was explained by both the quantity and quality (low‐molecular weight fractions) of the DOC. BP7 can be used as a measure of export of terrestrial organic carbon that is highly bioavailable.

3. Total export of DOC during spring flood from the different catchments ranged from 20 to 27 kg ha−1 and was negatively correlated to forest cover (%). However, the export of BP7 carbon was positively correlated to forest cover and varied from about 0.1 kg ha−1 in mire‐dominated streams to about 0.2 kg ha−1 in forest‐dominated streams.

4. The high bioavailability of forest carbon suggests that forests are the main contributors of BP‐supporting carbon in boreal streams although mires have higher area‐specific export of DOC.
Calibration of Terra/MODIS gross primary production over an irrigated cropland on the North China Plain and an alpine meadow on the Tibetan Plateau
Authors: ZHANG YONGQIANG , YU QIANG , JIANG JIE , TANG YANHONG
Published: February 2008

This paper evaluated the MODerate resolution Imaging Spectroradiometer (MODIS) gross primary production (GPP) product (MOD17) by using estimated GPP from eddy‐covariance flux measurements over an irrigated winter wheat and maize double‐cropping field on the North China Plain in 2003–2004, and an alpine meadow on the Tibetan Plateau in 2002–2003. The mean annual GPP from MOD17 accounted for 1/2–2/3 of the surface estimated mean annual GPP for the alpine meadow, but only about 1/5–1/3 for the cropland. This underestimation was partly attributed to low estimates of leaf area index by a MODIS product (MOD15) because it is used to calculate absorbed photosynthetically active radiation in the MOD17 algorithm. The main reason is that the parameter maximum light use efficiency (εmax) in the MOD17 algorithm was underestimated for the two biomes, especially for the cropland. Contrasted to the default, εmax was optimized using surface measurements. The optimized εmax for winter wheat, maize and meadow was 1.18, 1.81 and 0.73 g C/MJ, respectively. By using the surface measurements and optimized εmax , the MOD17 algorithm significantly improved the accuracy of GPP estimates. The optimum MOD17 algorithm explained about 82%, 68%, and 79% of GPP variance for winter wheat, maize, and meadow, respectively. These results suggest that it is necessary to adjust the MOD17 parameters for the estimation of cropland and meadow GPP, particularly over cropland.
Plant‐mediated effects of elevated ultraviolet‐B radiation on peat microbial communities of a subarctic mire
Authors: RINNAN RIIKKA , NERG ANNE‐MARJA , AHTONIEMI PAULIINA , SUOKANERVA HANNE , HOLOPAINEN TOINI , KYRÖ ESKO , BÅÅTH ERLAND
Published: February 2008

Elevated ultraviolet‐B (UVB) radiation has been reported to have few effects on plants but to alter the soil microbial community composition. However, the effects on soil microorganisms have to be mediated via plants, because direct radiation effects are only plausible on the uppermost millimeters of soil. Here, we assessed secondary effects of UVB on soil microbes. The responses in the dominant plant Eriophorum russeolum, peat pore water and microbial communities in the peat were recorded at a subarctic mire in the middle of the third growing season under field exposure simulating 20% depletion in the ozone layer. The UVB treatment significantly reduced the sucrose and the total soluble sugar (sucrose+glucose+fructose) concentration of the plant leaves while increasing the sucrose concentration in the belowground storage organ rhizome. The starch concentration of the leaves was also slightly reduced by elevated UVB. In the plant roots, carbohydrate concentrations remained unaffected but the total phenolics concentration increased under elevated UVB. We suggest that the simultaneously observed decrease in bacterial growth rate and the altered bacterial community composition are due to UVB‐induced changes in the plant photosynthate allocation and potential changes in root exudation. There were no effects of elevated UVB on microbial biomass, peat pore water or nutrient concentrations in the peat. The observed responses are in line with the previously reported lower ecosystem dark respiration under elevated UVB, and they signify that the changed plant tissue quality and lower bacterial activity are likely to reduce decomposition.
Coupling of respiration, nitrogen, and sugars underlies convergent temperature acclimation in Pinus banksiana across wide‐ranging sites and populations
Authors: TJOELKER MARK G. , OLEKSYN JACEK , REICH PETER B. , ŻYTKOWIAK ROMA
Published: February 2008

Patterns and mechanisms of short‐term temperature acclimation and long‐term climatic adaptation of respiration among intraspecific populations are poorly understood, but both are potentially important in constraining respiratory carbon flux to climate warming across large geographic scales, as well as influencing the metabolic fitness of populations. Herein we report on leaf dark respiration of 33‐year‐old trees of jack pine (Pinus banksiana Lamb.) grown in three contrasting North American common gardens (0.9, 4.6, and 7.9 °C, mean annual temperature) comprised of identical populations of wide‐ranging geographic origins. We tested whether respiration rates in this evergreen conifer acclimate to prevailing ambient air temperatures and differ among populations. At each of the common gardens, observed population differences in respiration rates measured at a standard temperature (20 °C) were comparatively small and largely unrelated to climate of seed‐source origin. In contrast, respiration in all populations exhibited seasonal acclimation at all sites. Specific respiration rates at 20 °C inversely tracked seasonal variation in ambient air temperature, increasing with cooler temperatures in fall and declining with warmer temperatures in spring and summer. Such responses were similar among populations and sites, thus providing a general predictive equation regarding temperature acclimation of respiration for the species. Temperature acclimation was associated with variation in nitrogen (N) and soluble carbohydrate concentrations, supporting a joint enzyme and substrate‐based model of respiratory acclimation. Regression analyses revealed convergent relationships between respiration and the combination of needle N and soluble carbohydrate concentrations and between N‐based respiration (RN, μmol mol N− 1 s− 1) and soluble carbohydrate concentrations, providing evidence for general predictive relationships across geographically diverse populations, seasons, and sites. Overall, these findings demonstrate that seasonal acclimation of respiration modulates rates of foliar respiratory carbon flux in a widely distributed evergreen species, and does so in a predictable way. Genetic differences in specific respiration rate appear less important than temperature acclimation in downregulating respiratory carbon fluxes with climate warming across wide‐ranging sites.
Artificial neural network approach to simultaneously predict shelf life of two varieties of packaged rice snacks
Authors: Siripatrawan Ubonrat , Jantawat Pantipa
Published: February 2008

Actual storage shelf life test by storing a packaged product under typical storage conditions is costly and time consuming. A new approach using an artificial neural network (ANN) algorithm for shelf life prediction of two varieties of moisture‐sensitive rice snacks packaged in polyethylene and polypropylene bags and stored at various storage conditions was established. The ANN used to predict the shelf life was based on multilayer perceptron with back propagation algorithm. The ANN algorithm employed the data of product characteristics, package properties and storage conditions. The neural network comprised an input, one hidden and one output layers. The network was trained using Bayesian regularisation. The performance of ANN was measured using regression coefficient (R2 = 0.23–0.28) and root mean square error (RMSE = 0.96–0.99). The ANN‐predicted shelf lives agreed very well with actual shelf life data. ANN could be used as an alternative method for shelf life prediction of moisture‐sensitive food products as well as product/package optimisation.
MRI study of bread baking: experimental device and MRI signal analysis
Authors: Wagner Muriel J. , Loubat Michel , Sommier Alain , Le Ray Dominique , Collewet Guylaine , Broyart Bertrand , Quintard Honoré , Davenel Armel , Trystram Gilles , Lucas Tiphaine
Published: February 2008

An oven dedicated to a magnetic resonance imager (MRI) was designed and constructed for continuous monitoring of the entire baking process. The general aim was to test whether response variables conventionally measured on bread loaves, such as temperature, density, and water loss, were consistent with those reported for similar products baked in classical convection ovens. MRI images acquired during baking are presented and discussed, emphasising the need to develop quantitative MRI methods allowing conversion of the MRI signal into one variable of interest, such as local density or local water content.
Changes in the processing quality of sugar beet (Beta vulgaris L.) during long‐term storage under controlled conditions
Authors: Kenter Christine , Hoffmann Christa M.
Published: February 2008

Long‐term storage of sugar beet is an option to extend the processing campaign of the sugar factories in Europe. In the present study, changes in the processing quality of sugar beet were quantified during 110 days of storage at 7 and 20 °C. During storage, the concentration of sucrose decreased whereas K, Na, amino N, betaine, invert sugar and raffinose accumulated in the beets, i.e. quality was impaired markedly. At 7 °C, the changes in sucrose concentration were relatively small but the formation of invert sugar and raffinose caused considerable losses in beet quality. Thus, long‐term storage at low temperature is appropriate to prolong the campaign but processing costs will increase. Quality assessment with two formulae showed that measurements of K, Na and amino N are insufficient to evaluate stored sugar beets for recoverable sugar. Due to its increase in storage, the concentration of invert sugar should also be taken into account.
Effects of ingredients and process conditions on ‘Amaretti’ cookies characteristics
Authors: Farris Stefano , Piergiovanni Luciano
Published: February 2008

This research aimed at determining the influence of different factors (i.e. ingredients and process conditions) on the most important characteristics defining consumers’ appreciation of ‘Amaretti’ cookies using DOE (design of experiment) technique. A different recipe than the original one was used in the manufacturing of the cookies, where saccharose was partially replaced with fructose and bamboo fibre was added as a new ingredient. Besides fructose/saccharose ratio and fibre, the effect of egg white, baking time and baking temperature on quality responses (hardness, water activity, moisture content and colour) of ‘Amaretti’ was measured by using a fractional factorial design in a screening test. Responses were affected mostly by changes in temperature and fructose/saccharose ratio levels and then by baking time; bamboo fibre had a statistically significant influence only on hardness. The power of fit of the regression models was significant for all four responses and had R2 value in the range of 0.886–0.997. However, the power of prediction was significant only for hardness, moisture content and colour and had Q2 value in the range of 0.584–0.965. The mathematical model for water activity resulted inappropriate to explain the link between factors and response. The achieved results can represent a useful tool to address and facilitate the next phase of optimisation.
The purpose and function of humour in health, health care and nursing: a narrative review
Authors: McCreaddie May , Wiggins Sally
Published: February 2008

Title.  The purpose and function of humour in health, health care and nursing: a narrative review

Aim.  This paper is a report of a review conducted to identify, critically analyse and synthesize the humour literature across a number of fields related to health, health care and nursing.

Background.  The humour–health hypothesis suggests that there is a positive link between humour and health. Humour has been a focus of much contention and deliberation for centuries, with three theories dominating the field: the superiority or tendentious theory, the incongruity theory and the relief theory.

Data sources.  A comprehensive literature search was carried out in January 2007 using a number of databases, keywords, manual recursive searching and journal alerts (January 1980–2007) cross‐referenced with the bibliographic databases of the International Society of Humor Studies. An inclusion and exclusion criterion was identified.

Review methods.  A narrative review of evidence‐ and non‐evidence‐based papers was conducted, using a relevant methodological framework with additional scrutiny of secondary data sources in the latter. Humour theories, incorporating definition, process and impact constituted a significant part of the appraisal process.

Results.  A total of 1630 papers were identified, with 220 fully sourced and 88 included in the final review. There is a dearth of humour research within nursing yet, ironically, an abundance of non‐evidence‐based opinion citing prerequisites and exclusion zones. Examination of physician–patient interaction and the humour–health hypothesis demonstrates that use of humour by patients is both challenging and revealing, particularly with regard to self‐deprecating humour.

Conclusion.  Nurses and nursing should adopt a circumspect and evidenced‐based approach to humour use in their work.
The empathetic response in nurses who treat pain: concept analysis
Authors: Campbell‐Yeo Marsha , Latimer Margot , Johnston Céleste
Published: February 2008

Title.  The empathetic response in nurses who treat pain: concept analysis

Aim. This paper is a report of a concept analysis of empathy.

Background. It is widely accepted that an empathetic response is necessary for nurses to deliver adequate pain relief and therapeutic care. Previous work suggests that empathy is a learned behaviour, and thus can be blocked if necessary to diminish personal distress.

Methods. A computerized search of the CINAHL, MEDLINE, PsycINFO, and Web of Science databases from 1980 to 2007 was conducted, using the keywords pain and empathy, both alone and in combination. Similar concepts such as sympathy, caring and compathy were included if the database distinguished between these concepts. Twenty‐five relevant articles were reviewed and Rodgers evolutionary concept analysis process was used to clarify the concept.

Findings. The recent observation that a mirror‐like neural response occurs in the brain of a person witnessing another in pain provides compelling evidence that empathetic arousal may occur independent of the previously described attributes of prior experience or learned cognitive appraisal.

Conclusion. While the empathetic response of care providers plays a central role in the recognition and treatment of pain, nurses are taught that regulation of this response is important to protect themselves against the traumatic effects of seeing patients in pain. However, there is emerging evidence that some elements of empathetic arousal are autonomic and therefore unable to be fully controlled; this may have important implications for nurses’ vulnerability.
Acknowledging communication: a milieu‐therapeutic approach in mental health care
Authors: Vatne Solfrid , Hoem Elisabeth
Published: February 2008

Title.  Acknowledging communication: a milieu‐therapeutic approach in mental health care

Aim.  This paper is a report of a study to develop milieu therapists’ acknowledging communication in their relationships with patients.

Background.  Gunderson’s therapeutic processes in milieu therapy have come into use in a broad range of mental health contexts in many countries. Research in nursing indicates that validation needs a more concrete development for use in clinical work.

Methods.  Schibbye’s theory, ‘Intersubjective relational understanding’, formed the theoretical foundation for a participatory action research project in 2004–2005. The data comprised the researcher’s process notes written during participation in the group of group leaders every second week over a period of 18 months, clinical narratives presented by participants in the same group, and eight qualitative interviews of members of the reflection group.

Findings.  The core concept in acknowledging communication, mutuality, was described as inter‐subjective sharing of feelings and beliefs in a respectful way. Participants presented their process of development as a movement from knowing what was best for the patient (acknowledging patients as competent persons, a milieu‐therapy culture based on conformity), to appreciating diversity and stubborn talk, to reflective wondering questions. Misunderstanding of acknowledgement occurred, for instance, in the form of always being supportive and affirmative towards patients.

Conclusion.  The concrete approaches in acknowledging communication presented in this article could be a fruitful basis for educating in and developing milieu therapy, both for nursing and in a multi‐professional approach in clinical practice and educational institutions. Future research should focus on broader development of various areas of acknowledging communication in practice, and should also include patients’ experiences of such approaches.
Childhood growth and cardiovascular reactivity to psychological stressors in late adulthood
Authors: Feldt K. , Räikkönen K. , Eriksson J. G. , Andersson S. , Osmond C. , Barker D. J. P. , Phillips D. I. W. , Kajantie E.
Published: February 2008

Objective.  Specific childhood growth patterns relate to risk of cardiovascular (CV) disease later in life, but the underlying mechanisms are unclear. We studied whether CV reactivity, a predictor of CV disease risk, is associated with childhood growth trajectories.

Methods.  A total of 144 (77 women and 67 men) participants of the Helsinki Birth Cohort Study born 1934–1944, whose height and weight were recorded repeatedly during the first 11 years, underwent the Trier Social Stress Test at the average age of 63 years. Beat‐to‐beat blood pressure was monitored via noninvasive finger photoplethysmograph (Finometer®), and CV reactivity scores were determined as the mean increment from baseline.

Results.  In both women and men, systolic blood pressure (SBP) reactivity increased by 3.8 mmHg (95% CI 0.8–6.9) and diastolic BP (DBP) reactivity by 1.4 mmHg (95% CI 0.0–2.8) for every standard deviation increase in gain in body mass index (kg m−2) between 7 and 11 years. By contrast, effects of height gain were dissimilar between sexes. In women, higher DBP reactivity was associated with a slow gain in height between 0 and 2 years, whilst in men higher SBP reactivity was associated with a slow gain in height between 2 and 7 years, which was preceded by a more rapid gain in height between 0 and 2 years. Adjusting for adult body size, body size at birth or childhood socio‐economic status did not change the results.

Conclusions.  We found that growth during childhood is associated with CV reactivity to stress later in adulthood. Early life programming of CV reactivity may partly underlie the link between early growth and CV disease.
Relationships between lipoprotein components and risk of myocardial infarction: age, gender and short versus longer follow‐up periods in the Apolipoprotein MOrtality RISk study (AMORIS)
Authors: Holme I. , Aastveit A. H. , Jungner I. , Walldius G.
Published: February 2008

Objectives.  Examine and compare lipoprotein components associated with fatal and nonfatal acute myocardial infarction (AMI) by time period in the Apolipoprotein MOrtality RISk (AMORIS) Study.

Design.  Prospective follow‐up study of nonfatal and fatal myocardial infarction through linkage with Swedish hospital discharge and Swedish mortality registers.

Setting.  Measurements of lipoprotein components from health check‐ups in the larger Stockholm area.

Subjects.  The AMORIS subjects (n = 149 121) free of AMI at blood sampling were followed from 1985 to 2002 with respect to n = 6794 first cases of AMI.

Results.  Hazard ratios of nonfatal and fatal AMI by lipoprotein parameters were highly significant and about equally strong in both genders. Apolipoprotein B (apoB), nonhigh density cholesterol and low density cholesterol predicted nonfatal AMI (NFAMI) better than fatal AMI, but high density cholesterol or apolipoprotein A‐1 did not. Atherogenic components were weaker predictors after 1997 than before. In multivariate analyses apoB/apoA‐1 was a better predictor than TC/HDL‐C. ApoB/apoA‐1 added clinically significant information to TC/HDL‐C in men as reflected by a net reclassification improvement (NRI) of 9.4% (P < 0.0001).

Conclusion.  ApoB, apoB/apoA‐1 and non‐HDL‐C were found about equally predictive with LDL‐C being slightly less, but multivariate analyses showed apoB/apoA‐1 to be the strongest predictor. Attenuation of prediction ability between nonfatal and fatal AMI may be due to modern treatment of CHD after a NFAMI and attenuation of hazard ratios after 1997 may be due to selection of lower risk subjects surviving to 1997.
Fluticasone and ibuprofen do not add to the effect of salmeterol on organic dust‐induced airway inflammation and bronchial hyper‐responsiveness
Authors: Strandberg K. , Ek A. , Palmberg L. , Larsson K.
Published: February 2008

Background.  Exposure in a pig house causes airway inflammation and bronchial hyper‐responsiveness which are not influenced by anti‐asthma drugs, including a β2‐agonist (salmeterol).

Objectives.  We hypothesized that a glucocorticoid or a cyclo‐oxygenase‐inhibitor synergistically interacts with salmeterol offering a protection against dust‐induced increased bronchial responsiveness and airway inflammation. As data did not confirm previous results a retrospective analysis of pooled data on dust‐induced bronchial hyper‐responsiveness from four other studies was performed.

Design.  Fluticasone or ibuprofen was administered for 1 week and salmeterol or placebo was inhaled 1 h prior to a 3‐h exposure in a pig barn in a double‐blind, placebo‐controlled, cross‐over design (2–3 weeks apart) in 12 healthy subjects. Lung function, bronchial responsiveness to methacholine and inflammatory markers were evaluated before and after exposure. Pre‐ and postexposure bronchial responsiveness in nontreated subjects was retrospectively evaluated from four previous studies.

Subjects.  Twelve healthy, nonatopic nonsmokers.

Results.  Salmeterol partially protected against bronchial hyper‐responsiveness but did not influence inflammatory markers. Fluticasone and ibuprofen did not add to these effects. The retrospective analysis showed that PD20FEV1 after exposure in a pig barn is almost totally independent of pre‐exposure PD20FEV1‐level; all subjects end up at the same low postexposure PD20FEV1.

Conclusion.  Contradictory to our previous results, salmeterol offered partial protection against enhanced bronchial responsiveness induced by exposure in a pig barn. This effect was not modified by fluticasone or ibuprofen. Our data clearly demonstrate that interventions altering bronchial responsiveness must be compared between groups with similar prechallenge bronchial responsiveness or in a cross‐over design.
Circulating KL‐6/MUC1 as an independent predictor for disseminated intravascular coagulation in acute respiratory distress syndrome
Authors: Nakashima T. , Yokoyama A. , Ohnishi H. , Hamada H. , Ishikawa N. , Haruta Y. , Hattori N. , Tanigawa K. , Kohno N.
Published: February 2008

Objectives.  Acute respiratory distress syndrome (ARDS) patients show high levels of circulating mucin including KL‐6/MUC1 (soluble MUC1 mucin). Because cancer mucin can bind vascular endothelial cells and platelets via selectins, mucin‐selectin interactions are reported to trigger platelet aggregation and intravascular coagulation. Therefore, we hypothesized that KL‐6/MUC1 is involved in the pathogenesis of disseminated intravascular coagulation (DIC) in ARDS. The aim of the current study is to evaluate the association between circulating KL‐6/MUC1 and DIC in ARDS patients.

Design.  Observational study with structured follow‐up.

Setting.  Intensive care unit in Hiroshima University Hospital.

Subjects.  Fifty‐six newly diagnosed patients with ARDS.

Interventions.  Circulating levels of KL‐6/MUC1 were measured during diagnosis and serially measured during the clinical course along with indices of respiratory failure, inflammation, coagulation and fibrinolysis and multiple organ dysfunction.

Results.  Acute respiratory distress syndrome patients complicated with DIC showed significantly higher levels of serum KL‐6/MUC1 than patients without DIC during the clinical course. Amongst the parameters analysed at diagnosis of ARDS, KL‐6/MUC1 was an independent predictor for DIC complication. The baseline level of circulating KL‐6/MUC1 at diagnosis of ARDS was significantly correlated with an increased DIC score following ARDS diagnosis. Using an optimum cutoff level of KL‐6/MUC1 obtained by a receiver operating characteristic curve, the sensitivity and specificity for predicting future DIC development in ARDS patients were 88.9% and 55.3%, respectively.

Conclusions.  These results suggest that KL‐6/MUC1 is associated with DIC development in ARDS patients. Elevated levels of KL‐6/MUC1 at diagnosis could be a predictor of DIC complication in ARDS.
Secular changes in cardiovascular risk factors and attack rate of myocardial infarction among men aged 50 in Gothenburg, Sweden. Accurate prediction using risk models
Authors: Wilhelmsen L. , Welin L. , Svärdsudd K. , Wedel H. , Eriksson H. , Hansson P.‐O. , Rosengren A.
Published: February 2008

Aims.  Coronary risk factor changes were related to attack rate of acute myocardial infarction (AMI).

Methods and results.  Cross‐sectional population samples of 50‐year‐old men were examined every 10th year from 1963 to 2003. Attack rates of AMI were recorded from 1975 to 2004. Prevalence of smoking decreased from 56% in 1963 to 22% in 2003. Leisure time physical activity decreased (n.s.), while psychological stress remained the same. Diabetes prevalence increased from 3.6% to 6.6%. Body mass index (BMI) increased from 24.8 to 26.4 kg m−2. Blood pressures decreased from 138.2/90.6 to 134.7/84.9 mmHg (P = 0.00001). Serum total cholesterol decreased from 6.42 to 5.50 mmol L−1 (P = 0.0001), but serum triglycerides increased from 1.26 to 1.71 mmol L−1 (P = 0.0001). The multivariable risk according to total cholesterol, blood pressure and smoking for AMI decreased from the set value 1.0 in 1963 to 0.418. From 1975–1979 to 2000–2004 attack rates for AMI for the age groups 35–44, 45–54 and 55–64 declined to 45%, 46% and 45%, respectively. The 28‐day case fatality declined from 30%, 38% and 46% to 12%, 16% and 20%.

Conclusion.  The more than 50% decline in attack rate of AMI during 30 years was comparable with the decline in risk factors.
Increased lipolysis by secretory phospholipase A2 group V of lipoproteins in diabetic dyslipidaemia
Authors: Pettersson C. , Fogelstrand L. , Rosengren B. , Ståhlman S. , Hurt‐Camejo E. , Fagerberg B. , Wiklund O.
Published: February 2008

Background.  Lipolysis of lipoproteins by secretory phospholipase A2 group V (sPLA2‐V) promotes inflammation, lipoprotein aggregation and foam cell formation – all considered as atherogenic mechanisms.

Objective.  In this study, we compared the susceptibility to sPLA2‐V lipolysis of VLDL and LDL from individuals with type 2 diabetes and the metabolic syndrome (T2D‐MetS) and from healthy controls.

Design.  VLDL and LDL were isolated from 38 T2D‐MetS subjects and 38 controls, treated pair‐wise. Extent of sPLA2‐V lipolysis was measured as release of nonesterified free fatty acids (NEFA). In a subset of the subjects, lipoprotein composition was determined as a relationship between lipid and apolipoprotein components.

Results.  Mean paired increase in sPLA2‐V lipolysis after 1 h for T2D‐MetS versus control was 2.0 μmol NEFA l−1 for VLDL (P = 0.004) and 0.75 μmol NEFA l−1 for LDL (P = 0.001). There were also substantial differences in lipoprotein composition between the groups. T2D‐MetS VLDL had higher triglyceride and cholesterol contents than control VLDL. T2D‐MetS LDL was smaller and contained more triglycerides and less cholesterol than control LDL. Both VLDL and LDL from T2D‐MetS subjects also contained more apolipoprotein CIII per particle.

Conclusion.  VLDL and LDL from T2D‐MetS individuals were more susceptible to sPLA2‐V lipolysis than those from control individuals. This may result in elevated levels of NEFA and lysophosphatidylcholine, both in circulation and in LDL, possibly contributing to the elevated inflammatory state and increased risk of cardiovascular diseases seen in these individuals.
Genetic structure of invasive earthwormsDendrobaena octaedrain the boreal forest of Alberta: insights into introduction mechanisms
Authors: CAMERON ERIN K. , BAYNE ERIN M. , COLTMAN DAVID W.
Published: February 2008

Population genetic studies can help to determine whether invasive species are established via single vs. multiple introduction events and also to distinguish among various colonization scenarios. We used this approach to investigate the introduction ofDendrobaena octaedra, a non‐native earthworm species, to the boreal forest of northern Alberta. The spread of non‐native earthworms in forested systems is not well understood, although bait abandonment and vehicular transport are believed to be important. Mitochondrial DNA sequencing revealed that multiple introductions of this species have occurred in northern Alberta, although individual populations may have been established by either single or multiple invaders introduced on one or more occasions. There was no relationship between genetic distances and either geographical distances or distances along road networks, suggesting that human‐mediated jump dispersal is more common than diffusive spread via road networks or via active dispersal. As well, genetic diversity was significantly greater at boat launches than roads, indicating that multiple introductions may be more likely to occur at those locations. Focusing management efforts on areas where multiple introductions are likely to occur may help to reduce invasive species’ potential for adaptive evolution and subsequent rapid spread.
Determining the origin and age of the Westland beech (Nothofagus) gap, New Zealand, using fungus beetle genetics
Authors: LESCHEN RICHARD A. B. , BUCKLEY THOMAS R. , HARMAN HELEN M. , SHULMEISTER JAMES
Published: February 2008

The formation and maintenance of theNothofagusbeech gap in the South Island, New Zealand, has been the focus of biogeographical debate since the 1920s. We examine the historical process of gap formation by investigating the population genetics of fungus beetles:Brachynopus scutellaris(Staphylinidae) inhabits logs and is absent from the beech gap, andHisparonia hystrix(Nitidulidae) is contiguous through the gap and is found commonly on sooty mould growing on several plant species. Both species show distinctive northern and southern haplotype distributions whileH. hystrixrecolonized the gap as shown by definitive mixing.B. scutellarisshows two major haplotype clades with strong geographical concordance, and unlikeH. hystrix,has clearly defined lineages that can be partitioned for molecular dating. Based on coalescence dating methods, disjunct lineages ofB. scutellarisindicate that the gap was formed less than 200 000 years ago. Phylogenetic imprints from both species reveal similar patterns of population divergence corresponding to recent glacial cycles, favouring a glacial explanation for the origin of the gap. Post‐gap colonization byH. hystrixmay have been facilitated by the spread ofLeptospermum scopariumhost trees to the area, and they may be better at dispersing thanB. scutellariswhich may be constrained by fungal host and/or microhabitat. The gap‐excluded speciesB. scutellarisis found in both beech and podocarp‐broadleaf forests flanking the Westland gap and its absence in the gap may be related to incomplete recolonization following glacial retreat. We also discuss species status and an ancient polymorphism withinB. scutellaris.
Ancient hybridization and mitochondrial capture between two species of chipmunks
Authors: GOOD JEFFREY M. , HIRD SARAH , REID NOAH , DEMBOSKI JOHN R. , STEPPAN SCOTT J. , MARTIN‐NIMS TINA R. , SULLIVAN JACK
Published: February 2008

Models that posit speciation in the face of gene flow are replacing classical views that hybridization is rare between animal species. We use a multilocus approach to examine the history of hybridization and gene flow between two species of chipmunks (Tamias ruficaudus and T. amoenus). Previous studies have shown that these species occupy different ecological niches and have distinct genital bone morphologies, yet appear to be incompletely isolated reproductively in multiple areas of sympatry. We compared data from four sequenced nuclear loci and from seven microsatellite loci to published cytochrome b sequences. Interspecific gene flow was primarily restricted to introgression of the T. ruficaudus mitochondrial genome into a sympatric subspecies of T. amoenus, T. a. canicaudus, with the four sequenced nuclear loci showing little to no interspecific allele sharing. Microsatellite data were consistent with high levels of differentiation between the species and also showed no current gene flow between broadly sympatric populations of T. a. canicaudus and T. ruficaudus. Coalescent analyses date the mtDNA introgression event from the mid‐Pleistocene to late Pliocene. Overall, these data indicate that introgression has had a minimal impact on the nuclear genomes of T. amoenus and T. ruficaudus despite multiple independent hybridization events. Our findings challenge long‐standing assumptions on patterns of reproductive isolation in chipmunks and suggest that there may be other examples of hybridization among the 23 species of Tamias that occur in western North America.
Mitochondrial DNA reveals multiple Northern Hemisphere introductions of Caprella mutica (Crustacea, Amphipoda)
Authors: ASHTON GAIL V. , STEVENS MARK I. , HART MARK C. , GREEN DAVID H. , BURROWS MICHAEL T. , COOK ELIZABETH J. , WILLIS KATE J.
Published: February 2008

Caprella mutica (Crustacea, Amphipoda) has been widely introduced to non‐native regions in the last 40 years. Its native habitat is sub‐boreal northeast Asia, but in the Northern Hemisphere, it is now found on both coasts of North America, and North Atlantic coastlines of Europe. Direct sequencing of mitochondrial DNA (cytochrome c oxidase subunit I gene) was used to compare genetic variation in native and non‐native populations of C. mutica. These data were used to investigate the invasion history of C. mutica and to test potential source populations in Japan. High diversity (31 haplotypes from 49 individuals), but no phylogeographical structure, was identified in four populations in the putative native range. In contrast, non‐native populations showed reduced genetic diversity (7 haplotypes from 249 individuals) and informative phylogeographical structure. Grouping of C. mutica populations into native, east Pacific, and Atlantic groups explained the most among‐region variation (59%). This indicates independent introduction pathways for C. mutica to the Pacific and Atlantic coasts of North America. Two dominant haplotypes were identified in eastern and western Atlantic coastal populations, indicating several dispersal routes within the Atlantic. The analysis indicated that several introductions from multiple sources were likely to be responsible for the observed global distribution of C. mutica, but the pathways were least well defined among the Atlantic populations. The four sampled populations of C. mutica in Japan could not be identified as the direct source of the non‐native populations examined in this study. The high diversity within the Japan populations indicates that the native range needs to be assessed at a far greater scale, both within and among populations, to accurately assess the source of the global spread of C. mutica.
Interspecific hybridization and restricted trans‐Pacific gene flow in the Tropical Eastern Pacific Pocillopora
Authors: COMBOSCH DAVID J. , GUZMAN HECTOR M. , SCHUHMACHER HELMUT , VOLLMER STEVEN V.
Published: February 2008

Coral reefs in the Tropical Eastern Pacific (TEP) are among the most isolated in the world. This isolation has resulted in relatively low species diversity but comparatively high endemism. The dominant reef‐building corals of the TEP are the Pocillopora corals, a ubiquitous Indo‐Pacific genus commonly regarded as inferior reef‐builder. In addition to being the dominant reef‐builders in the TEP, the Pocilloporids have undergone a reproductive shift from internally brooding larvae through most of their Indo‐Pacific range to free‐spawning in the TEP. Using genetic data from the internally transcribed spacer (ITS) regions of the nuclear ribosomal DNA gene cluster, we show here that this apparent reproductive shift coincides with interspecific hybridization among TEP Pocillopora species. We document a pattern of one‐way gene flow into the main TEP reef builder P. damicornis from one or both of its TEP congeners —P. eydouxi and P. elegans. Our data provide preliminary evidence that trans‐Pacific gene flow in P. damicornis between the Central and Eastern Pacific is restricted as well (ΦST = 0.419, P < 0.0001). In combination, these results suggest that Eastern Pacific corals exist in relative isolation from their Central Pacific counterparts and interact with each other differently via hybridization.
Can we stop transgenes from taking a walk on the wild side?
Authors: DLUGOSCH KATRINA M. , WHITTON JEANNETTE
Published: February 2008

Whether the potential costs associated with broad‐scale use of genetically modified organisms (GMOs) outweigh possible benefits is highly contentious, including within the scientific community. Even among those generally in favour of commercialization of GM crops, there is nonetheless broad recognition that transgene escape into the wild should be minimized. But is it possible to achieve containment of engineered genetic elements in the context of large scale agricultural production? In a previous study, Warwick et al. (2003) documented transgene escape via gene flow from herbicide resistant (HR) canola (Brassica napus) into neighbouring weedy B. rapa populations (Fig. 1) in two agricultural fields in Quebec, Canada. In a follow‐up study in this issue of Molecular Ecology, Warwick et al. (2008) show that the transgene has persisted and spread within the weedy population in the absence of selection for herbicide resistance. Certainly a trait like herbicide resistance is expected to spread when selected through the use of the herbicide, despite potentially negative epistatic effects on fitness. However, Warwick et al.'s findings suggest that direct selection favouring the transgene is not required for its persistence. So is there any hope of preventing transgene escape into the wild?

Weedy Brassica rapa (orange flags) growing in a B. napus field. (Photo: MJ Simard)

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MicroRNA399 is a long‐distance signal for the regulation of plant phosphate homeostasis
Authors: Pant Bikram Datt , Buhtz Anja , Kehr Julia , Scheible Wolf‐Rüdiger
Published: February 2008

The presence of microRNA species in plant phloem sap suggests potential signaling roles by long‐distance regulation of gene expression. Proof for such a role for a phloem‐mobile microRNA is lacking. Here we show that phosphate (Pi) starvation‐induced microRNA399 (miR399) is present in the phloem sap of two diverse plant species, rapeseed and pumpkin, and levels are strongly and specifically increased in phloem sap during Pi deprivation. By performing micro‐grafting experiments using Arabidopsis, we further show that chimeric plants constitutively over‐expressing miR399 in the shoot accumulate mature miR399 species to very high levels in their wild‐type roots, while corresponding primary transcripts are virtually absent in roots, demonstrating shoot‐to‐root transport. The chimeric plants exhibit (i) down‐regulation of the miR399 target transcript (PHO2), which encodes a critical component for maintenance of Pi homeostasis, in the wild‐type root, and (ii) Pi accumulation in the shoot, which is the phenotype of pho2 mutants, miR399 over‐expressers or chimeric plants with a genetic knock‐out of PHO2 in the root. Hence the transported miR399 molecules retain biological activity. This is a demonstration of systemic control of a biological process, i.e. maintenance of plant Pi homeostasis, by a phloem‐mobile microRNA.
Interplay between MAMP‐triggered and SA‐mediated defense responses
Authors: Tsuda Kenichi , Sato Masanao , Glazebrook Jane , Cohen Jerry D. , Katagiri Fumiaki
Published: February 2008

Plants respond to pathogen infection using an innate immune system with at least two distinct recognition mechanisms. One mechanism recognizes microbe‐associated molecular patterns (MAMPs). The other is based on resistance (R) genes and specifically recognizes certain pathogen virulence factors, including those delivered through the type III secretion system (TTSS) of bacteria. Salicylic acid (SA)‐mediated responses are an important part of the R gene‐mediated defense. Substantial overlaps between MAMP‐triggered and SA‐mediated responses have been reported. However, interactions between MAMP‐triggered and SA‐mediated signaling mechanisms have not been well documented. Here we report intimate interactions between MAMP‐triggered and SA‐mediated signaling. We found that SA accumulated at a higher level 6 h after treatment with a MAMP, flg22 or inoculation with Pseudomonas syringae pv. tomato DC3000 (PstDC3000) hrcC mutant, which is deficient in TTSS function. Disruptions of SA signaling components, such as SID2 and PAD4, strongly affected MAMP‐triggered responses monitored by expression profiling. We found two groups of genes that were induced by PstDC3000 hrcC in an SA‐dependent manner. One group was SID2‐dependent at all time points, whereas the other was SID2‐independent at early time points and SID2‐dependent at later time points. Thus, the expression of the latter genes responds to MAMPs through both SA‐independent and SA‐dependent signaling mechanisms. Strong resistance to PstDC3000 hrcC was dependent on SA signaling. These results indicate that the SA increase triggered by MAMPs is a major component of the MAMP‐triggered signaling mechanism, explaining the overlapping spectra of MAMP‐triggered and SA‐mediated responses.
Role of a GDSL lipase‐like protein as sinapine esterase in Brassicaceae
Authors: Clauß Kathleen , Baumert Alfred , Nimtz Manfred , Milkowski Carsten , Strack Dieter
Published: February 2008

The seeds of most members of the Brassicaceae accumulate high amounts of sinapine (sinapoylcholine) that is rapidly hydrolyzed during early stages of seed germination. One of three isoforms of sinapine esterase activity (BnSCE3) has been isolated from Brassica napus seedlings and subjected to trypsin digestion and spectrometric sequencing. The peptide sequences were used to isolate BnSCE3 cDNA, which was shown to contain an open reading frame of 1170 bp encoding a protein of 389 amino acids, including a leader peptide of 25 amino acids. Sequence comparison identified the protein as the recently cloned BnLIP2, i.e. a GDSL lipase‐like protein, which displays high sequence identity to a large number of corresponding plant proteins, including four related Arabidopsis lipases. The enzymes belong to the SGNH protein family, which use a catalytic triad of Ser‐Asp‐His, with serine as the nucleophile of the GDSL motif. The corresponding B. napus and Arabidopsis genes were heterologously expressed in Nicotiana benthamiana leaves and proved to confer sinapine esterase activity. In addition to sinapine esterase activity, the native B. napus protein (BnSCE3/BnLIP2) showed broad substrate specificity towards various other choline esters, including phosphatidylcholine. This exceptionally broad substrate specificity, which is common to a large number of other GDSL lipases in plants, hampers their functional analysis. However, the data presented here indicate a role for the GDSL lipase‐like BnSCE3/BnLIP2 as a sinapine esterase in members of the Brassicaceae, catalyzing hydrolysis of sinapine during seed germination, leading, via 1‐O‐sinapoyl‐β‐glucose, to sinapoyl‐l‐malate in the seedlings.