bluuebunny/crossref_metadata_2025 huggingface dataset:
Hidden phylogeographic complexity in the Sierra Madre Oriental: the case of the Mexican tulip poppy Hunnemannia fumariifolia (Papaveraceae)
Authors: Sosa Victoria , Ruiz‐Sanchez Eduardo , Rodriguez‐Gomez Flor C.
Published: July 2008

Aim  A phylogeographic study of the endemic Mexican tulip poppy Hunnemannia fumariifolia (Papaveraceae) was conducted to determine: (1) the historical processes that influenced its geographical pattern of genetic variation; (2) whether isolation by distance was one of the main factors that caused genetic divergence in populations of this species; and (3) whether genetic flow still exists between populations from northern arid zones (Chihuahuan Desert and Sierra Madre Oriental) and those from southern arid zones (Tehuacán‐Cuicatlán Valley) – populations that are separated by the Transvolcanic Belt.

Location  Xerophytic vegetation in Mexico.

Methods  Chloroplast DNA (cpDNA) sequences of three regions, trnH‐psbA, rpl32‐trnL(UAG) and ndhF‐rpl32, were obtained for 85 individuals from 17 populations sampled in the field, covering the entire range of H. fumariifolia. The evolutionary history of these populations was investigated using a nested clade phylogeographic analysis and also by conducting various population genetic analyses.

Results  In total, 17 haplotypes were detected, 14 of which were found in the Sierra Madre Oriental. Differentiation among populations based on cpDNA variation (GST = 0.787, SE 0.0614) indicated population structure in H. fumariifolia, corroborated by a fixation index (FST) of 0.907. Results from analysis of molecular variance found that most of the total variation (90.71%, P < 0.001) was explained by differences among populations. Three regions were determined based on geological correspondence – the Chihuahuan Desert, Sierra Madre Oriental and Tehuacán‐Cuicatlán Valley – and the variation between them was significant (43.39%, P < 0.001). Results of a Mantel test showed a significant correlation between genetic and geographic distances (r = 0.511; P = 0.0001), suggesting a pattern of isolation by distance, which was corroborated by nested clade phylogeographic analysis. Mismatch distribution analysis indicated a sudden demographic expansion.

Main conclusions  Our study found that isolation by distance influenced genetic divergence in populations of H. fumariifolia. The finding that allopatric fragmentation influenced genetic divergence in populations in the Sierra Madre Oriental may be a reflection of the complex geology of the area. Our results suggest that the areas located in the north of the Sierra Madre Oriental acted as post‐glacial refugia for some populations.
Nurses’ experiences of and opinions about using standardised care plans in electronic health records – a questionnaire study
Authors: Dahm Marie Fogelberg , Wadensten Barbro
Published: July 2008

Aim.  The aim of the present study was to investigate nurses’ opinions about using standardised care plans in electronic health record and quality standards for clinical practice.

Background.  Following introduction of an electronic health record, use of standardised care plans and quality standards has increased among nurses at two hospitals in Sweden. Understanding nurses’ opinions is important to continued development in this area. There are few previous studies on nurses’ opinions about standardised care plans.

Design.  Survey.

Method.  The study was quantitative, descriptive and based on a questionnaire. The questionnaire included items on nurses’ knowledge of and opinions about standardised care plans and quality standards.

Results.  The majority of the nurses were of the opinion that standardised care plans increase their ability to provide the same high‐quality basic care for all patients. They also thought that a common standardised care plan across several professions would improve conditions for provision of high‐quality care. The majority of the nurses also felt that the quality standards are a prerequisite of maintaining standardised care plans of high quality. There was no consensus on whether standardised care plans increase the risk of failing to notice patients’ individual problems. Most agreed that standardised care plans decrease documentation time as well as redundant documentation. The study showed that training is needed to teach nurses how to use standardised care plans in care provision.

Conclusions.  The nurses in the study had positive attitudes towards use of standardised care plans and felt that they could facilitate nursing practice.

Relevance to clinical practice.  Use of standardised care plans can improve nursing documentation and facilitate work for nurses. Moreover, it can support nurses in their use of evidence‐based nursing methods. The present study shows that nurses have positive attitudes, which could facilitate continued use of standardised care plans.
Strong genetic population structure in the boring giant clam, Tridacna crocea, across the Indo‐Malay Archipelago: implications related to evolutionary processes and connectivity
Authors: KOCHZIUS MARC , NURYANTO AGUS
Published: July 2008

Even though the Indo‐Malay Archipelago hosts the world's greatest diversity of marine species, studies on the genetic population structure and gene flow of marine organisms within this area are rather rare. Consequently, not much is known about connectivity of marine populations in the Indo‐Malay Archipelago, despite the fact that such information is important to understand evolutionary and ecological processes in the centre of marine biodiversity. This study aims to investigate the genetic population structure of the boring giant clam, Tridacna crocea. The analysis is based on a 456‐bp fragment of the cytochrome oxidase I gene from 300 individuals collected from 15 localities across the Indo‐Malay Archipelago. Tridacna crocea shows a very strong genetic population structure and isolation by distance, indicating restricted gene flow between almost all sample sites. The observed ΦST‐value of 0.28 is very high compared to other studies on giant clams. According to the pronounced genetic differences, the sample sites can be divided into four groups from West to East: (i) Eastern Indian Ocean, (ii) Java Sea, (iii) South China Sea, Indonesian throughflow, as well as seas in the East of Sulawesi, and (iv) Western Pacific. This complex genetic population structure and pattern of connectivity, characterised by restricted gene flow between some sites and panmixing between others can be attributed to the geological history and prevailing current regimes in the Indo‐Malay Archipelago.
Phylogeography of the invasive weed Hypochaeris radicata (Asteraceae): from Moroccan origin to worldwide introduced populations
Authors: ORTIZ M. Á. , TREMETSBERGER K. , TERRAB A. , STUESSY T. F. , GARCÍA‐CASTAÑO J. L. , URTUBEY E. , BAEZA C. M. , RUAS C. F. , GIBBS P. E. , TALAVERA S.
Published: July 2008

In an attempt to delineate the area of origin and migratory expansion of the highly successful invasive weedy species Hypochaeris radicata, we analysed amplified fragment length polymorphisms from samples taken from 44 populations. Population sampling focused on the central and western Mediterranean area, but also included sites from Northern Spain, Western and Central Europe, Southeast Asia and South America. The six primer combinations applied to 213 individuals generated a total of 517 fragments of which 513 (99.2%) were polymorphic. The neighbour‐joining tree presented five clusters and these divisions were supported by the results of Bayesian analyses: plants in the Moroccan, Betic Sierras (Southern Spain), and central Mediterranean clusters are all heterocarpic. The north and central Spanish, southwestern Sierra Morena, and Central European, Asian and South American cluster contain both heterocarpic (southwestern Sierra Morena) and homocarpic populations (all other populations). The Doñana cluster includes two homocarpic populations. Analyses of fragment parameters indicate that the oldest populations of H. radicata are located in Morocco and that the species expanded from this area in the Late Quaternary via at least three migratory routes, the earliest of which seems to have been to the southwestern Iberian Peninsula, with subsequent colonizations to the central Mediterranean area and the Betic Sierras. Homocarpic populations originated in the southwestern Iberian Peninsula and subsequently spread across north and central Spain, Central Europe and worldwide, where they became a highly successful weed.
Scanning the genome for gene single nucleotide polymorphisms involved in adaptive population differentiation in white spruce
Authors: NAMROUD MARIE‐CLAIRE , BEAULIEU JEAN , JUGE NICOLAS , LAROCHE JÉRÔME , BOUSQUET JEAN
Published: July 2008

Conifers are characterized by a large genome size and a rapid decay of linkage disequilibrium, most often within gene limits. Genome scans based on noncoding markers are less likely to detect molecular adaptation linked to genes in these species. In this study, we assessed the effectiveness of a genome‐wide single nucleotide polymorphism (SNP) scan focused on expressed genes in detecting local adaptation in a conifer species. Samples were collected from six natural populations of white spruce (Picea glauca) moderately differentiated for several quantitative characters. A total of 534 SNPs representing 345 expressed genes were analysed. Genes potentially under natural selection were identified by estimating the differentiation in SNP frequencies among populations (FST) and identifying outliers, and by estimating local differentiation using a Bayesian approach. Both average expected heterozygosity and population differentiation estimates (HE = 0.270 andFST = 0.006) were comparable to those obtained with other genetic markers. Of all genes, 5.5% were identified as outliers withFSTat the 95% confidence level, while 14% were identified as candidates for local adaptation with the Bayesian method. There was some overlap between the two gene sets. More than half of the candidate genes for local adaptation were specific to the warmest population, about 20% to the most arid population, and 15% to the coldest and most humid higher altitude population. These adaptive trends were consistent with the genes’ putative functions and the divergence in quantitative traits noted among the populations. The results suggest that an approach separating the locus and population effects is useful to identify genes potentially under selection. These candidates are worth exploring in more details at the physiological and ecological levels.
Female house wrens (Troglodytes aedon) increase the size, but not immunocompetence, of their offspring through extra‐pair mating
Authors: FORSMAN ANNA M.  , VOGEL LAURA A.  , SAKALUK SCOTT K.  , JOHNSON BONNIE G.  , MASTERS BRIAN S.  , JOHNSON L. SCOTT , THOMPSON CHARLES F. 
Published: July 2008

House wrens are typically socially monogamous, but frequently engage in extra‐pair matings leading to multisired broods. Because females do not appear to acquire direct material benefits from their extra‐pair mates, we tested the hypothesis that female house wrens derive indirect genetic benefits, such as enhanced immunocompetence (cutaneous immune activity, humoral immunity, and plasma bactericidal activity) and condition (size and haematoserological traits) for their offspring, by mating polyandrously. We predicted that extra‐pair young (EPY) should show greater immune responsiveness and better body condition than their within‐pair maternal half‐siblings (WPY). Contrary to our prediction, WPY had higher cutaneous immune activity than their EPY brood‐mates in two of three years, and EPY and WPY did not differ in measures of innate and humoral immunity. WPY also had higher albumin to γ‐globulin ratios than EPY; however, they were not in better condition based on other measures. EPY had consistently longer tarsi (a measure of long‐bone size) than their WPY half‐siblings, suggesting that females engage in extra‐pair copulations with larger males. The benefits of large structural size in the study population is unknown, but based on evidence from other passerines, we suggest that structural size may be an important fitness‐related trait in house wrens. We conclude that our results are not consistent with the hypothesis that females gain immune‐related benefits for their offspring by engaging in extra‐pair matings. Further study of the fitness consequences of differences in tarsus length is needed to determine whether females acquire size‐related benefits for their offspring from extra‐pair mates.
A SINE of restricted gene flow across the Alpine Fault: phylogeography of the New Zealand common skink (Oligosoma nigriplantare polychroma)
Authors: LIGGINS LIBBY , CHAPPLE DAVID G. , DAUGHERTY CHARLES H. , RITCHIE PETER A.
Published: July 2008

New Zealand has experienced a complex climatic and geological history since the Pliocene. Thus, identifying the processes most important in having driven the evolution of New Zealand's biota has proven difficult. Here we examine the phylogeography of the New Zealand common skink (Oligosoma nigriplantare polychroma) which is distributed throughout much of New Zealand and crosses many putative biogeographical boundaries. Using mitochondrial DNA sequence data, we revealed five geographically distinct lineages that are highly differentiated (pairwise ΦST 0.54–0.80). The phylogeographical pattern and inferred age of the lineages suggests Pliocene mountain building along active fault lines promoted their divergence 3.98–5.45 million years ago. A short interspersed nuclear element (SINE) polymorphism in the myosin gene intron (MYH‐2) confirmed a pattern of restricted gene flow between lineages on either side of the mountain ranges associated with the Alpine Fault that runs southwest to northeast across the South Island of New Zealand. An analysis of molecular variance confirmed that ~40% of the genetic differentiation in O. n. polychroma is distributed across this major fault line. The straits between the main islands of New Zealand accounted for much less of the variation found within O. n. polychroma, most likely due to the repeated existence of landbridges between islands during periods of the Pleistocene that allowed migration. Overall, our findings reveal the relative roles of different climatic and geological processes, and in particular, demonstrate the importance of the Alpine Fault in the evolution of New Zealand's biota.
Invasion of Europe by the western corn rootworm, Diabrotica virgifera virgifera: multiple transatlantic introductions with various reductions of genetic diversity
Authors: CIOSI M. , MILLER N. J. , KIM K. S. , GIORDANO R. , ESTOUP A. , GUILLEMAUD T.
Published: July 2008

The early stages of invasion involve demographic bottlenecks that may result in lower genetic variation in introduced populations as compared to source population/s. Low genetic variability may decrease the adaptive potential of such populations in their new environments. Previous population genetic studies of invasive species have reported varying levels of losses of genetic variability in comparisons of source and invasive populations. However, intraspecific comparisons are required to assess more thoroughly the repeatability of genetic consequences of colonization events. Descriptions of invasive species for which multiple introductions from a single source population have been demonstrated may be particularly informative. The western corn rootworm (WCR), Diabrotica virgifera virgifera, native to North America and invasive in Europe, offers us an opportunity to analyse multiple introduction events within a single species. We investigated within‐ and between‐population variation at eight microsatellite markers in WCR in North America and Europe to investigate the routes by which WCR was introduced into Europe, and to assess the effect of introduction events on genetic variation. We detected five independent introduction events from the northern USA into Europe. The diversity loss following these introductions differed considerably between events, suggesting substantial variation in introduction, foundation and/or establishment conditions. Genetic variability at evolutionarily neutral loci does not seem to underlie the invasive success of WCR in Europe. We also showed that the introduction of WCR into Europe resulted in the redistribution of genetic variance from the intra‐ to the interpopulational level contrary to most examples of multiple introductions.
Phylogeographical structure and temporal complexity in American sweetgum (Liquidambar styraciflua; Altingiaceae)
Authors: MORRIS ASHLEY B. , ICKERT‐BOND STEFANIE M. , BRUNSON D. BURKE , SOLTIS DOUGLAS E. , SOLTIS PAMELA S.
Published: July 2008

Eastern North American plant biogeography has traditionally focused on two primary issues: (i) the location of temperate Pleistocene refugia and their proximity to the southern margin of the ice sheet during the last glacial maximum, and (ii) the origin of the temperate element of northern Latin America. While numerous population genetic and phylogeographical studies have focused on the first issue, few (if any) have considered the second. We addressed these issues by surveying 117 individuals from 24 populations of Liquidambar styraciflua (American sweetgum; Altingiaceae) across the southeastern USA, eastern Mexico, and Guatemala, using more than 2200 bp of chloroplast DNA sequence data. To specifically address the issue of timing, we estimated intraspecific divergence times on the basis of multiple fossil‐based calibration points, using taxa from Altingiaceae (Liquidambar and Altingia) and Hammamelidaceae (Hamamelis) as outgroups. More than half of the sampled localities exhibited multiple haplotypes. Remarkably, the greatest variation was observed within the USA, with Mexico and Guatemala sharing widespread haplotypes with Texas, Mississippi, Kentucky, Ohio, and northern Virginia. This lack of differentiation suggests shared ancestral polymorphisms, and that the genetic signal we observed is older than the disjunction itself. Our data provide support for previously proposed hypotheses of Pleistocene refugia in peninsular Florida and along the eastern Atlantic, but also for deeper divergences (~8 million years ago) within the USA. These patterns reflect a dynamic biogeographical history for eastern North American trees, and emphasize the importance of the inclusion of a temporal component in any phylogeographical study.
Transport and compartmentation of phosphite in higher plant cells – kinetic and 31P nuclear magnetic resonance studies
Authors: DANOVA‐ALT RALITZA , DIJKEMA COR , DE WAARD PIETER , KÖCK MARGRET
Published: July 2008

Phosphite (Phi, H2PO3‐), being the active part of several fungicides, has been shown to influence not only the fungal metabolism but also the development of phosphate‐deficient plants. However, the mechanism of phosphite effects on plants is still widely unknown. In this paper we analysed uptake, subcellular distribution and metabolic effects of Phi in tobacco BY‐2 cells using in vivo31P nuclear magnetic resonance (31P‐NMR) spectroscopy. Based on the kinetic properties of the phosphate transport system of tobacco BY‐2 cells, it was demonstrated that phosphite inhibited phosphate uptake in a competitive manner. To directly follow the fate of phosphate and phosphite in cytoplasmic and vacuolar pools of tobacco cells, we took advantage of the pH‐sensitive chemical shift of the Phi anion. The NMR studies showed a distinct cytoplasmic accumulation of Phi in Pi‐deprived cells, whereas Pi resupply resulted in a rapid efflux of Phi. Pi‐preloaded cells shifted Phi directly into vacuoles. These studies allowed for the first time to follow Phi flux processes in an in vivo setting in plants. On the other hand, the external Pi nutrition status and the metabolic state of the cells had a strong influence on the intracellular compartmentalization of xenobiotic Phi.
Molecular mechanisms underlying plant memory in JA‐mediated defence responses
Authors: GÁLIS IVAN , GAQUEREL EMMANUEL , PANDEY SHREE P. , BALDWIN IAN T.
Published: July 2008

Plants must respond to biotic and abiotic challenges to optimize their Darwinian fitness in nature. Many of these challenges occur repeatedly during a plant's lifetime, and their sequence and timing can profoundly influence the fitness outcome of a plant's response. The ability to perceive, store and recall previous stressful events is likely useful for efficient, rapid and cost‐effective responses, but we know very little about the mechanisms involved. Using jasmonate‐elicited anti‐herbivore defence responses as an example, we consider how ‘memories’ of previous attacks could be created in (1) the biosynthetic processes involved in the generation of the oxylipin bursts elicited by herbivore attacks; (2) the perception of oxylipins and their transduction into cellular events by transcription factors and transcriptional activators; and (3) the role of small RNAs in the formation of long‐term stress imprints in plants.
Depositional processes in a kimberlite crater: the Upper Cretaceous Orapa South Pipe (Botswana)
Authors: GERNON THOMAS M. , FIELD MATTHEW , SPARKS R. STEPHEN J.
Published: July 2008

The Orapa A/K1 Diamond Mine, Botswana, exposes the crater facies of a bilobate kimberlite pipe of Upper Cretaceous age. The South Crater consists of layered volcaniclastic deposits which unconformably cross‐cut massive volcaniclastic kimberlite of diatreme facies in the North Pipe. Based on the depositional structure, grain‐size, sorting and composition of kimberlite in the South Crater, six units are distinguished in the ∼70 m thick stratiform crater‐fill sequence and talus slope deposits close to the crater wall, which represents a multistage infill of the volcanic crater. Monolithic basalt breccias (Unit 1) near the base of the crater‐fill are interpreted as rock‐fall avalanche deposits, generated by the sector collapse of the crater walls. These deposits are overlain by a basal imbricated lithic breccia and upper massive sub‐unit (Unit 2), interpreted as the deposits of a pyroclastic flow that entered the South Crater from another source. Vertical degassing structures within the massive sub‐unit show evidence for elutriation of fines and probably were formed after emplacement by fluidization due to air entrainment. Units 3 and 5 are thinly stratified deposits, characterized by diffuse bedding, reverse and normal grading, coarse lenticular beds, mudstone beds, small‐scale scour channels and load casts. These units are attributed to rapidly emplaced sheet floods on the crater floor. Units 3 and 5 are directly overlain by poorly sorted volcaniclastic kimberlite (Units 4 and 6) rich in basalt boulders, attributed to debris flows formed by the collapse of crater walls. Unit 7 comprises medium sandstones to cobble conglomerates representing talus fans, which were active throughout the deposition of Units 1 to 6. The study demonstrates that much of the material infilling the South Crater is derived externally after eruption, including primary pyroclastic flow deposits probably from another kimberlite pipe. These findings have important implications for predicting diamond grade. Results may also aid the interpretation of crater sequences of ultra‐basic, basaltic and intermediate volcanoes, together with the deposits of topographic basins in sub‐aerial settings.
Characterization of Arabidopsis mur3 mutations that result in constitutive activation of defence in petioles, but not leaves
Authors: Tedman‐Jones Jennifer D. , Lei Rita , Jay Florence , Fabro Georgina , Li Xuemei , Reiter Wolf‐Dieter , Brearley Charles , Jones Jonathan D. G.
Published: July 2008

A screen was established for mutants in which the plant defence response is de‐repressed. The pathogen‐inducible isochorismate synthase (ICS1) promoter was fused to firefly luciferase (luc) and a homozygous transgenic line generated in which the ICS1:luc fusion is co‐regulated with ICS1. This line was mutagenized and M2 seedlings screened for constitutive ICS1:luc expression (cie). The cie mutants fall into distinct phenotypic classes based on tissue‐specific localization of luciferase activity. One mutant, cie1, that shows constitutive luciferase activity specifically in petioles, was chosen for further analysis. In addition to ICS1, PR and other defence‐related genes are constitutively expressed in cie1 plants. The cie1 mutant is also characterized by an increased production of conjugated salicylic acid and reactive oxygen intermediates, as well as spontaneous lesion formation, all confined to petiole tissue. Significantly, defences activated in cie1 are sufficient to prevent infection by a virulent isolate of Hyaloperonospora parasitica, and this enhanced resistance response protects petiole tissue alone. Furthermore, cie1‐mediated resistance, along with PR gene expression, is abolished in a sid2‐1 mutant background, consistent with a requirement for salicylic acid. A positional cloning approach was used to identify cie1, which carries two point mutations in a gene required for cell wall biosynthesis and actin organization, MUR3. A mur3 knockout mutant also resists infection by H. parasitica in its petioles and this phenotype is complemented by transformation with wild‐type MUR3. We propose that perturbed cell wall biosynthesis may activate plant defence and provide a rationale for the cie1 and the mur3 knockout phenotypes.
A sequence‐anchored genetic linkage map for the moss, Physcomitrella patens
Authors: Kamisugi Yasuko , Von Stackelberg Mark , Lang Daniel , Care Matthew , Reski Ralf , Rensing Stefan A. , Cuming Andrew C.
Published: July 2008

The moss Physcomitrella patens is a model for the study of plant cell biology and, by virtue of its basal position in land plant phylogeny, for comparative analysis of the evolution of plant gene function and development. It is ideally suited for ‘reverse genetic’ analysis by virtue of its outstanding ability to undertake targeted transgene integration by homologous recombination. However, gene identification through mutagenesis and map‐based cloning has hitherto not been possible, due to the lack of a genetic linkage map. Using molecular markers [amplified fragment length polymorphisms (AFLP) and simple sequence repeats (SSR)] we have generated genetic linkage maps for Physcomitrella. One hundred and seventy‐nine gene‐specific SSR markers were mapped in 46 linkage groups, and 1574 polymorphic AFLP markers were identified. Integrating the SSR‐ and AFLP‐based maps generated 31 linkage groups comprising 1420 markers. Anchorage of the integrated linkage map with gene‐specific SSR markers coupled with computational prediction of AFLP loci has enabled its correspondence with the newly sequenced Physcomitrella genome. The generation of a linkage map densely populated with molecular markers and anchored to the genome sequence now provides a resource for forward genetic interrogation of the organism and for the development of a pipeline for the map‐based cloning of Physcomitrella genes. This will radically enhance the potential of Physcomitrella for determining how gene function has evolved for the acquisition of complex developmental strategies within the plant kingdom.
Tic40 is important for reinsertion of proteins from the chloroplast stroma into the inner membrane
Authors: Chiu Chi‐Chou , Min Li Hsou–
Published: July 2008

Chloroplast inner‐membrane proteins Tic40 and Tic110 are first imported from the cytosol into the chloroplast stroma, and subsequently reinserted from the stroma into the inner membrane. However, the mechanism of reinsertion remains unclear. Here we show that Tic40 itself is involved in this reinsertion process. When precursors of either Tic40 or a Tic110 C‐terminal truncate, tpTic110‐Tic110N, were imported into chloroplasts isolated from a tic40‐null mutant, soluble Tic40 and Tic110N intermediates accumulated in the stroma of tic40‐mutant chloroplasts, due to a slower rate of reinsertion. We further show that a larger quantity of soluble Tic21 intermediates also accumulated in the stroma of tic40‐mutant chloroplasts. In contrast, inner‐membrane insertion of the triose‐phosphate/phosphate translocator was not affected by the tic40 mutation. Our data suggest that multiple pathways exist for the insertion of chloroplast inner‐membrane proteins.
Red ‘Anjou’ pear has a higher photoprotective capacity than green ‘Anjou’
Authors: Li Pengmin , Castagnoli Steve , Cheng Lailiang
Published: July 2008

Photoprotective function of anthocyanins along with xanthophyll cycle and antioxidant system in fruit peel was investigated in red ‘Anjou’ vs green ‘Anjou’ pear (Pyrus communis) during fruit development and in response to short‐term exposure to high light. The sun‐exposed peel of red ‘Anjou’ had higher maximum quantum yield of photosystem II (FV/FM) than that of green ‘Anjou’ and both the sun‐exposed peel and the shaded peel of red ‘Anjou’ had smaller decreases in FV/FM after 2‐h high light (photon flux density of 1500 μmol m−2 s−1) treatment than those of green ‘Anjou’. At the middle and late developmental stages, the xanthophyll cycle pool size on a chlorophyll basis, the activity of superoxide dismutase, ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) and the level of reduced ascorbate and total ascorbate pool in the sun‐exposed peel were either the same or lower in red ‘Anjou’ than in green ‘Anjou’, whereas the xanthophyll cycle pool size on a chlorophyll basis and the activity of APX, catalase, MDAR, DHAR and GR in the shaded peel were higher in red ‘Anjou’ than in green ‘Anjou’. It is concluded that red ‘Anjou’ has a higher photoprotective capacity in both the sun‐exposed peel and the shaded peel than green ‘Anjou’. While the higher anthocyanin concentration along with the larger xanthophyll cycle pool size and the higher activity of some antioxidant enzymes may collectively contribute to the higher photoprotective capacity in the shaded peel of red ‘Anjou’, the higher photoprotective capacity in the sun‐exposed peel of red ‘Anjou’ is mainly attributed to its higher anthocyanin concentration.
Measuring and comparing evolvability and constraint in multivariate characters
Authors: HANSEN T. F. , HOULE D.
Published: July 2008

The Lande equation forms the basis for our understanding of the short‐term evolution of quantitative traits in a multivariate context. It predicts the response to selection as the product of an additive genetic variance matrix and a selection gradient. The selection gradient approximates the force and direction of selection, and the genetic variance matrix quantifies the role of the genetic system in evolution. Attempts to understand the evolutionary significance of the genetic variance matrix are hampered by the fact that the majority of the methods used to characterize and compare variance matrices have not been derived in an explicit theoretical context. We use the Lande equation to derive new measures of the ability of a variance matrix to allow or constrain evolution in any direction in phenotype space. Evolvability captures the ability of a population to evolve in the direction of selection when stabilizing selection is absent. Conditional evolvability captures the ability of a population to respond to directional selection in the presence of stabilizing selection on other trait combinations. We then derive measures of character autonomy and integration from these evolvabilities. We study the properties of these measures and show how they can be used to interpret and compare variance matrices. As an illustration, we show that divergence of wing shape in the dipteran family Drosophilidae has proceeded in directions that have relatively high evolvabilities.
Cell death upon H2O2 induction in the unicellular green alga Micrasterias
Authors: Darehshouri A. , Affenzeller M. , Lütz‐Meindl U.
Published: July 2008

In the present study, we investigated whether the unicellular green alga Micrasterias denticulata is capable of executing programmed cell death (PCD) upon experimental induction, and which morphological, molecular and physiological hallmarks characterise this. This is particularly interesting as unicellular freshwater green algae growing in shallow bog ponds are exposed to extreme environmental conditions, and the capacity to perform PCD may be an important strategy to guarantee survival of the population. The theoretically ‘immortal’ alga Micrasterias is an ideal object for such investigations as it has served as a cell biological model system for many years and details on its growth properties, physiology and ultrastructure throughout the cell cycle are well known. Treatments with low concentrations of H2O2 are known to induce PCD in other organisms, resulting in severe ultrastructural changes to organelles, as observed in TEM. These include deformation and part disintegration of mitochondria, abnormal dilatation of cisternal rims of dictyosomes, occurrence of multivesicular bodies, an increase in the number of ER compartments, and slight condensation of chromatin. Additionally, a statistically significant increase in caspase‐3‐like activity was detected, which was abrogated by a caspase‐3 inhibitor. Photosynthetic activity measured by fast chlorophyll fluorescence decreased as a consequence of H2O2 exposure, whereas pigment composition, except for a reduction in carotenoids, was the same as in untreated controls. TUNEL positive staining and ladder‐like degradation of DNA, both frequently regarded as a hallmark of PCD in higher plants, could only be detected in dead Micrasterias cells.
Wheat (Triticum aestivum) seedlings secrete proteases from the roots and, after protein addition, grow well on medium without inorganic nitrogen
Authors: Adamczyk B. , Godlewski M. , Zimny J. , Zimny A.
Published: July 2008

This paper reports on the role of proteases secreted by roots in nitrogen capture by plants. The study was conducted on aseptically cultivated wheat seedlings (Triticum aestivum cv. Tacher) obtained from embryos isolated from grains. Seedlings were cultivated for 21 days on deionised water, Murashige Skoog medium (MS), MS without inorganic nitrogen (IN), and MS without IN, in which IN was replaced by casein (0.01%, 0.1% or 1%). Comparison of seedlings grown on these media showed that casein entirely compensated for the lack of inorganic nitrogen in the medium. Shoots and roots of seedlings cultivated on MS medium with this protein had higher fresh weight than those cultivated on MS medium without casein. The increase in fresh weight of seedlings was correlated with casein concentration and proteolytic activity in the medium. In conclusion, wheat that uses proteases secreted by the roots can directly utilise proteins in the medium as a source of nitrogen without prior digestion by microbial proteases and without protein mineralisation. These results suggest the important role of organic nitrogen fertilisers in increasing wheat yield.
Transfer of selected mineral nutrients and trace elements in the host–hemiparasite association, Cistus–Odontites lutea, growing on and off metal‐polluted sites
Authors: Llugany M. , Lombini A. , Dinelli E. , Poschenrieder C. , Barceló J.
Published: July 2008

The role of a hemiparasitic life‐style in plant resistance to toxic trace elements in polluted soils is unclear. Restriction of metal uptake by the host, restriction of metal transfer from host to parasite, or transformation of metals into a less toxic form may play a role. This study analysed the transfer of selected mineral elements from soil to host (Cistus spp.) and from host to hemiparasite (Odontites lutea) at locations with different metal burdens: a Cu‐rich serpentine site, Pb–Ba mine spoil and an unpolluted soil. Highest soil‐to‐host transfer factors for K, Mg, Ca, Zn, Cu and Pb were observed on the unpolluted soil. Statistically significant differences among locations of host‐to‐parasite transfer factors were only found for Ca and Pb. Restriction of transfer of unfavourable Ca/Mg ratios, characteristic at the serpentine site, and of high Pb and Zn concentrations at the Pb–Ba mine occurred mainly at the soil–host, and not at the host–parasite, level. Odontites lutea was able to withstand enhanced Zn and Pb concentrations and low Fe/Cu ratios in shoot tissue without developing toxicity symptoms. This could be caused by specific metal resistance mechanisms in this hemiparasite and/or the transformation and transfer of these metals into a less toxic form by the metal‐tolerant host.
Transparent Testa Glabra 1 (TTG1) and TTG1‐like genes in Matthiola incana R. Br. and related Brassicaceae and mutation in the WD‐40 motif
Authors: Dressel A. , Hemleben V.
Published: July 2008

TTG1 (Transparent Testa Glabra 1), a WD‐40 repeat protein, is involved in regulation of flavonoid/anthocyanin biosynthesis, seed coat (mucilage) development/pigmentation and trichome formation in leaves. Here, we characterized the TTG1 gene of Matthiola incana wild type (e locus), showing 85.3% similarity to TTG1 of A. thaliana on the nucleotide level and 96.2% on the protein level. A white‐flowered and glabrous mutant, line 17, of M. incana exhibits one nucleotide change, leading to an amino acid substitution directly in the WD motif (W158R). Correspondingly, the DFR (dihydroflavonol 4‐reductase) gene, in which the expression is known to be dependent on TTG1, is not expressed in Matthiola mutant lines 17 (and 19). Comparison of the GC content of the Matthiola TTG1 (54.1%) and Arabidopsis TTG1 (46.1%) genes revealed a strong difference, mostly obtained by neutral substitutions (C to T transitions). To examine whether this is an ecologically influenced trend, a fragment of TTG1 was characterized from another Matthiola species (M. tricuspidata) and from Malcolmia flexuosa subsp. naxensis from the eastern Mediterranean, near a beach with sandy and salty soils. Both Matthiola species have a higher GC content in the TTG1 gene than Arabidopsis and the closer‐related Malcolmia, indicating that the GC content is rather an evolutionary than an ecological signal. A similar WD‐40 repeat protein gene (containing no intron in the 3′ untranslated region) with high similarity to the Arabidopsis TTG1‐like (AtAN11) gene was found in Matthiola.
Reduced lung uptake of Iodine‐123 metaiodobenzylguanidine in high‐altitude pulmonary oedema
Authors: URUSHIHATA Kazuhisa , KOIZUMI Tomonobu , HANAOKA Masayuki , FUJIMOTO Keisaku , KUBO Keishi , KOBAYASHI Toshio , FUJII Tadashige
Published: July 2008

Background and objective:  Iodine‐123 metaiodobenzylguanidine (123I‐MIBG) uptake in the lungs is a potentially suitable marker of pulmonary endothelial function because MIBG behaviour in the pulmonary circulation is quantitatively similar to that of norepinephrine. In addition, hypoxia reduces 123I‐MIBG transport in pulmonary endothelial cells in vitro. The present study was undertaken to evaluate 123I‐MIBG uptake in the lungs of patients with high‐altitude pulmonary oedema (HAPE).

Methods:  123I‐MIBG scintigraphy was performed in eight patients with HAPE. The findings were compared with those in 24 patients with congestive heart failure due to idiopathic dilated cardiomyopathy (DCM) and in 13 normal control subjects. In patients with HAPE, the 123I‐MIBG examination was performed 7–14 days after admission. Anterior planar images were acquired 15 min after injection of 123I‐MIBG and the total lung to upper mediastinum ratio (L/M ratio) was calculated for both lungs.

Results:  The L/M ratio in patients with HAPE (1.39 ± 0.15, mean ± SD) was significantly lower than in those with congestive heart failure/DCM (1.66 ± 0.16) or in normal controls (1.53 ± 0.14). There were no significant differences among the groups in 123I‐MIBG accumulation in the heart.

Conclusions:  Although the mechanism of altered 123I‐MIBG kinetics in HAPE remains obscure, decreased 123I‐MIBG uptake in the lungs may potentially be a suitable technique for the assessment of pathological conditions associated with the pulmonary endothelium.
Low‐dose dexamethasone alleviates lipopolysaccharide‐induced acute lung injury in rats and upregulates pulmonary glucocorticoid receptors
Authors: WANG Xiao‐Qiu , ZHOU Xin , ZHOU Yan , RONG Ling , GAO Lei , XU Wei
Published: July 2008

Background and objective:  The major causes of mortality among patients who survive acute lung injury/ARDS (ALI/ARDS) are due to the extensive tissue remodelling and fibrosis. Use of high‐dose glucocorticoids to reduce these inflammatory and fibroproliferative responses has been shown to do more harm than good. Recently, Meduri et al. found that the early use of low‐dose prolonged methylprednisolone in patients with severe ALI/ARDS significantly relieved the systemic inflammatory response and improved pulmonary and extrapulmonary organ function. This study investigated the therapeutic effect of low‐dose dexamethasone (Dex) on inflammation and fibrosis in LPS‐induced ALI in rats and its influence on the expression of the pulmonary glucocorticoid receptor (GR).

Methods:  Eighty Wistar rats were randomly divided into four groups: a control group (intraperitoneal normal saline injection (5 mL/kg) throughout experiment, n = 24); the LPS model group (LPS injection (5 mg/kg) for 3 days and normal saline thereafter, n = 24); the LPS + Dex group (LPS injection for 3 days and Dex solution (5 mg/kg) thereafter, n = 16); and the Dex group (normal saline injection (5 mL/kg) for 3 days and Dex solution (5 mg/kg) thereafter, n = 16). Levels of tumor necrosis factor‐α, matrix metallopeptidase‐9 and procollagen N‐terminal propeptide type I in BAL fluid were examined by ELISA on the third, seventh and fourteenth days after injection. Pulmonary hydroxyproline content was measured and histological examination was performed with haematoxylin–eosin and Victoria blue‐ponceau. Pulmonary distribution of GR‐positive cells was examined immunohistochemically, and expression of GR mRNA and protein was determined by RT‐PCR and western blot analysis.

Results:  Histological assessments showed that pulmonary fibrosis occurred in parallel with inflammation in the rat ALI model. Compared with the LPS group, the inflammation and fibrosis parameters were significantly improved in the LPS + Dex group at different periods after injection (P < 0.05 or P < 0.01), although parameters in the LPS + Dex group were not as good as those of the control group. GR mRNA and protein expression in the LPS + Dex group were markedly higher than that of the LPS group on the seventh and the fourteenth days (both P < 0.01). Western blotting showed that Dex also promoted the nuclear translocation of GR protein.

Conclusion:  Low‐dose Dex can reduce pulmonary inflammation and fibrosis after LPS‐induced ALI in rats and can elevate GR expression in the lung, probably through upregulating GR levels and promoting the nuclear translocation of GR protein.
Pleural effusion in patients with pulmonary embolism
Authors: YAP Elaine , ANDERSON Graeme , DONALD Jennifer , WONG Conroy A. , LEE Y.C. Gary , SIVAKUMARAN Pathmanathan
Published: July 2008

Background and objective:  It has been suggested that pulmonary embolism (PE) is an under‐recognized cause of pleural effusion. This study aimed to (i) establish the incidence and clinical relevance of pleural effusion in patients with pulmonary emboli; and (ii) determine if there is a relationship between development of pleural effusions and the location of emboli and number of pulmonary arteries involved.

Methods:  A retrospective analysis of all CT pulmonary angiograms (CTPA) performed over 12 months on adult patients with clinically suspected PE in a hospital which used CTPA as first‐line imaging investigation for PE.

Results:  Of 285 CTPA, 60 patients (21%) had evidence of pulmonary emboli (38 had both central and peripheral clots and 22 peripheral emboli only). Emboli were bilateral in 39 cases and unilateral in 21 cases. Pleural effusion was present in almost one half (n = 29, 48%) of the patients with pulmonary emboli. Patients with pulmonary emboli were more likely to have a pleural effusion (OR 2.2 (95% CI: 1.1–4.7), P < 0.05) than patients without PE; however, the effusions were generally very small. Most (86%) of the effusions were present on the same side as the emboli. The location of emboli and number of arteries involved did not predict the presence of pleural effusions.

Conclusions:  Pleural effusion is common in patients with pulmonary emboli demonstrated on CTPA. These effusions are small and seldom alter clinical management. Clinicians should therefore have a high threshold of suspicion in attributing large or contralateral pleural effusions to embolic diseases without excluding alternative diagnoses.
Bronchoperitoneal fistula from a lung abscess
Authors: HSU Po‐Shun , LEE Shih‐Chun , TZAO Ching , CHEN Cheng‐Jueng , CHENG Yeung‐Leung
Published: July 2008

Fistula formation between the bronchi and peritoneal cavity is extremely rare. In previous reports, fistulas have occurred secondary to thoraco‐abdominal trauma, subphrenic abscess, suppurative biliary tract obstruction, malignancy and iatrogenically through procedures such as biliary surgery or percutaneous biliary drainage. The direction of fistula formation has always been thought to be from the peritoneal cavity to the bronchi: there are no reports of a fistula with a bronchial origin. This case report presents a patient who presented with sepsis and a bronchoperitoneal fistula and pneumoperitoneum secondary to lung abscess.
Revision of the severity rating and classification of hospital‐acquired pneumonia in the Japanese Respiratory Society guidelines
Authors: SEKI Masafumi , WATANABE Akira , MIKASA Keiichi , KADOTA Junichi , KOHNO Shigeru
Published: July 2008

Background and objective:  Based on the results of a multicentre collaborative survey of hospital‐acquired pneumonia (HAP) conducted in Japan, the severity rating and classification of pneumonia in the Japanese Respiratory Society guidelines for management of HAP were examined.

Methods:  Parameters for the severity classification were selected from the factors associated with prognosis in the HAP survey and in other previous reports. Depending on the presence of the parameters listed below, patients with HAP were stratified into those with high, moderate or low‐risk. The high‐risk group was defined as patients with three or more of the following risk factors: ‘malignant tumour or immunocompromised status’, ‘impaired consciousness’, ‘requiring fraction of inspired oxygen (FiO2) >35% to maintain SaO2 >90%’, ‘man aged 70 years or older, or woman aged 75 years or older’ and ‘oliguria or dehydration.’ The moderate‐risk group was defined as patients with any of the secondary risk factors as follows: ‘CRP ≥ 200 mg/L’ and ‘extent of infiltration on CXR covers at least 2/3 of one lung’. The low‐risk group was defined as all other patients.

Results:  Application of this classification scheme to the patients enrolled in the HAP survey revealed a mortality rate of 40.8% (98/240) in the high‐risk group, which was significantly higher than the mortality rates in the moderate and low‐risk groups: 24.9% (69/277) and 12.1% (101/834), respectively.

Conclusion:  These results indicate that it is possible to classify patients using these parameters as prognostic indicators.