bluuebunny/crossref_metadata_2025 huggingface dataset:
Glycaemic index methodology
Authors: Brouns F. , Bjorck I. , Frayn K. N. , Gibbs A. L. , Lang V. , Slama G. , Wolever T. M. S.
Published: July 2005

The glycaemic index (GI) concept was originally introduced to classify different sources of carbohydrate (CHO)-rich foods, usually having an energy content of >80 % from CHO, to their effect on post-meal glycaemia. It was assumed to apply to foods that primarily deliver available CHO, causing hyperglycaemia. Low-GI foods were classified as being digested and absorbed slowly and high-GI foods as being rapidly digested and absorbed, resulting in different glycaemic responses. Low-GI foods were found to induce benefits on certain risk factors for CVD and diabetes. Accordingly it has been proposed that GI classification of foods and drinks could be useful to help consumers make ‘healthy food choices’ within specific food groups. Classification of foods according to their impact on blood glucose responses requires a standardised way of measuring such responses. The present review discusses the most relevant methodological considerations and highlights specific recommendations regarding number of subjects, sex, subject status, inclusion and exclusion criteria, pre-test conditions, CHO test dose, blood sampling procedures, sampling times, test randomisation and calculation of glycaemic response area under the curve. All together, these technical recommendations will help to implement or reinforce measurement of GI in laboratories and help to ensure quality of results. Since there is current international interest in alternative ways of expressing glycaemic responses to foods, some of these methods are discussed.
Isoflavones and endothelial function
Authors: Hall Wendy L. , Rimbach Gerald , Williams Christine M.
Published: July 2005

Dietary isoflavones are thought to be cardioprotective due to their structural similarity to oestrogen. Oestrogen is believed to have beneficial effects on endothelial function and may be one of the mechanisms by which premenopausal women are protected against CVD. Decreased NO production and endothelial NO synthase activity, and increased endothelin-1 concentrations, impaired lipoprotein metabolism and increased circulating inflammatory factors result from oestrogen deficiency. Oestrogen acts by binding to oestrogen receptors α and β. Isoflavones have been shown to bind with greater affinity to the latter. Oestrogen replacement therapy is no longer thought to be a safe treatment for prevention of CVD; isoflavones are a possible alternative. Limited evidence from human intervention studies suggests that isoflavones may improve endothelial function, but the available data are not conclusive. Animal studies provide stronger support for a role of isoflavones in the vasculature, with increased vasodilation and endothelial NO synthase activity demonstrated. Cellular mechanisms underlying the effects of isoflavones on endothelial cell function are not yet clear. Possible oestrogen receptor-mediated pathways include modulation of gene transcription, and also non-genomic oestrogen receptor-mediated signalling pathways. Putative non-oestrogenic pathways include inhibition of reactive oxygen species production and up regulation of the protein kinase A pathway (increasing NO bioavailability). Further research is needed to unravel effects of isoflavones on intracellular regulation of the endothelial function. Moreover, there is an urgent need for adequately powered, robustly designed human intervention studies in order to clarify the present equivocal findings.
The role of functional foods in the psychobiology of health and disease
Authors: Hamer Mark , Owen Gail , Kloek Joris
Published: July 2005

The effect of psychological stress on health is becoming a serious concern, with figures from the World Health Organization showing that stress-related disorders affect nearly 450 million individuals worldwide. Heightened physiological stress responses and psychosocial factors have been linked to disease pathways such as hypertension and CVD. This has prompted significant interest within the scientific community, public health bodies and industry to employ interventions to control and reduce the impact of stress on health. There is now strong potential for functional foods to offer stress management benefits. Various physiological pathways have been targeted by specific dietary supplements for stress reduction, including the hypothalamic–pituitary–adrenal axis and sympathetic nervous system. Presently there are a number of ingredients, which include vitamin C, milk proteins, a number of herbal extracts (ginkgo biloba, ginseng, kava, valerian and lemon balm), andn-3 fatty acids, that have demonstrated potential stress reactivity-lowering and mood-enhancing effects, although further work is required to substantiate the efficacy in human subjects. Dietary supplements that can alleviate excessive stress responses may play an increasingly important role for the maintenance of health in a stressful environment. However, future research should employ a greater range of measures that will provide stronger evidence to substantiate functional food claims for stress relief.
Odour from animal production facilities: its relationship to diet
Authors: Le Phung D. , Aarnink André J. A. , Ogink Nico W. M. , Becker Petra M. , Verstegen Martin W. A.
Published: July 2005

Though bad odour has always been associated with animal production, it did not attract much research attention until in many countries the odour production and emission from intensified animal production caused serious nuisance and was implicated in the health problems of individuals living near animal farms. Odour from pig production facilities is generated by the microbial conversion of feed in the large intestine of pigs and by the microbial conversion of pig excreta under anaerobic conditions and in manure stores. Assuming that primary odour-causing compounds arise from an excess of degradable protein and a lack of specific fermentable carbohydrates during microbial fermentation, the main dietary components that can be altered to reduce odour are protein and fermentable carbohydrates. In the present paper we aim to give an up-to-date review of studies on the relationship between diet composition and odour production, with the emphasis on protein and fermentable carbohydrates. We hypothesise how odour might be changed and/or reduced by altering the diet of pigs. Research so far has mainly focused on the single effects of different levels of crude protein and fermentable carbohydrates on odour production. However, also important for odour formation are the sources of protein and fermentable carbohydrates. In addition, it is not only the amount and source of these compounds that is important, but also the balance between them. On the basis of our review of the literature, we hypothesise that odour nuisance from pig production facilities might be reduced significantly if there is an optimum balance between protein and fermentable carbohydrates in the diet of pigs.
Pathophysiological and clinical aspects of malnutrition in chronic renal failure
Authors: Caimi G. , Carollo C. , Lo Presti R.
Published: July 2005

Kidney diseases are the ninth leading cause of death in the USA. In these patients cardiovascular mortality is greater than in the general population. This observation, not completely explained by the so-called ‘traditional’ cardiovascular risk factors, lead the authors to postulate other ‘emerging’ ones found in chronic renal failure patients. Among these new findings, nutritional status, considered as the balance existing between nutrient requirements and intakes, plays an important role for the development of cardiovascular diseases. In fact several nutritional parameters are widely known as pathophysiological determinants of cardiovascular disturbances, which are based on accelerated atherosclerosis, due especially to enhanced oxidative stress and endothelial dysfunction. Chronic renal failure is a clinical condition that from many points of view seems to be a chronic inflammatory state, and many studies confirm this observation. This influences nutritional status especially in dialysis patients. Malnutrition is related in turn to accelerated atherosclerosis thus leading to a postulated ‘malnutrition, inflammation, atherosclerosis’ (MIA) syndrome in which malnutrition, inflammation and atherosclerosis contribute to an elevated cardiovascular mortality rate. The present review explores this issue, first by describing epidemiological aspects of malnutrition in chronic renal failure patients and then by analysing the specific biochemical and metabolic features of these patients.
Sexing fish by palpation: a simple method for gonadal assessment of fluvial salmonids
Authors: Kano Y.
Published: July 2005

This paper presents a non‐destructive sexing method that can be employed in fluvial salmonids and presumably some other taxa of fish. The sex of a fish is identified and assessed by indirectly palpating the gonad.
Does client size affect cleaner fish choice of client? An empirical test using client fish models
Authors: Grutter A. S. , Glover S. , Bshary R.
Published: July 2005

To determine whether the choice of client fishes in the cleaner fish Labroides dimidiatus was influenced by client size, cleaner fish were given a choice of equal amount of food spread on large and small client redfin butterflyfish Chaetodon trifasciatus models. All large models received bites from cleaners compared to 27% for small models. Seventy‐nine per cent of cleaners took their first bite from the large fish model. The results suggest that client size may affect cleaner fish choice.
Haematology and leucocyte morphology of wild caught Thunnus maccoyii
Authors: Rough K. M. , Nowak B. F. , Reuter R. E.
Published: July 2005

The haematology of wild southern bluefin tuna Thunnus maccoyii was described using blood samples collected from fish immediately after they were caught. Cytology and cytochemistry revealed that the blood in peripheral circulation is comprised of erythrocytes, reticulocytes, ghost cells, lymphocytes, thrombocytes, eosinophilic granulocytes, neutrophilic granulocytes and monocytes. Reference ranges established were 41·09–55·50% for haematocrit, 0·62–3·00% for leucocrit, 13·25–17·92 g dl−1 for haemoglobin and 2·1–2·9 million erythrocytes μl−1 for erythrocyte count. Differential cell counts showed 94·58 ± 2·15% erythrocytes, 3·99 ± 1·44% leucocytes and 1·43 ± 1·03% thrombocytes (mean ± s.d.). Normal ranges for differential leucocyte counts were 0·00–5·45% for neutrophils, 0·69–12·06% for eosinophils, 0·00–5·03% for monocytes, 46·97–74·32% for lymphocytes and 14·47–43·92% for thrombocytes. Erythrocyte indices, leucocyte types and cytochemistry were comparable to other species of scombrids. Packed cell volume was sensitive to the physiological state of the fish and to sample handling technique.
Is the marginal otolith increment width a reliable recent growth index for larval and juvenile herring?
Authors: Fey D. P.
Published: July 2005

Marginal otolith increment width analysis was performed on field‐collected larval and juvenile spring‐spawned herring Clupea harengus that experienced variable feeding conditions and high temperatures that were above the optimum for growth. Although drastic zooplankton biomass reduction had a significant effect on increment width, a delay of a few days in the otolith response was observed. More importantly, a very clear, positive temperature effect on marginal increment width was demonstrated in fish characterized by temperature independent somatic growth. These results indicate that under natural conditions it may be impossible to distinguish increment width changes related to variation in feeding conditions from changes caused by temperature fluctuations. Therefore, it was concluded that marginal otolith increment width analysis could not be used as a recent growth index (IG) for herring larvae and juveniles exposed to drastic temperature fluctuations. The implication of these results is significant not only for the use of marginal increments as a recent growth index, but also if growth rate backcalculation is to be used as a research method.
Growth and morphological development of sagittal otoliths of larval and early juvenile Trachurus japonicus
Authors: Xie S. , Watanabe Y. , Saruwatari T. , Masuda R. , Yamashita Y. , Sassa C. , Konishi Y.
Published: July 2005

The daily periodicity of growth increment formation in sagittal otoliths of jack mackerel Trachurus japonicus was validated by marking otoliths with alizarin complexone (ALC). Analysis of otoliths of known‐age juveniles confirmed that the first increment formed on day 3 after hatching, and was associated with first feeding. A total of 198 specimens, ranging from 2·6 to 49·2 mm in body length (notochord length or standard length) and from 7 to 78 days in age, were collected in the East China Sea and Tosa Bay, and used to examine the association between otolith morphological development and ontogenetic development. The relationship between body length (L) and otolith radius (R) was significantly described by the linear function L = 2·65 + 0·0425R(n = 198, r2 = 0·99, P < 0·001), indicating that somatic growth history can be reconstructed from otolith growth patterns. The otolith was primarily spherical in the preflexion larval stage, and became elongated with notochord flexion. The first secondary primordium formed at c. 25 days, during the middle postflexion stage, and was associated with metamorphosis. By c. 42 days the sagittal otolith was adult‐like in morphology, with the primary growth zone enclosed by the marginal growth zone, except in the anterior rostrum area. Thus age, growth and developmental stages were recorded in sagittal otoliths during the larval and early juvenile stages of jack mackerel.
Hatch date‐dependent differences in early growth and development recorded in the otolith microstructure of Trachurus japonicus
Authors: Xie S. , Watanabe Y.
Published: July 2005

Otolith microstructure of 308 juvenile jack mackerel Trachurus japonicus sampled in the southern Sea of Japan between June and September 2002 were examined by light microscopy. Hatch‐date distribution indicated a protracted spawning season from 16 January to 30 May 2002. The first secondary primordium (SP) was formed at ages 19–54 days, with a mean ± s.d. of 30·4 ± 6·1. The number of SP in an otolith ranged from two to 15, with a mean of 6·1 ± 1·7. Age of the first SP formation, number of SP and increment width varied with hatch date. In general, late‐hatched fish were younger when the first SP formed, and had a higher number of SP and wider increments, than early‐hatched fish. As increment width is a linear function of somatic growth and formation of the first SP is associated with metamorphosis in jack mackerel, these variations in otolith microstructure indicated that rates of growth (as inferred from wider increments) and development (as inferred by younger age of first SP formation) were higher in late‐hatched fish relative to early‐hatched fish. Higher temperature experienced by late‐hatched fish during early life stages may contribute critically to their higher growth and development rates compared to early‐hatched fish.
Do egg size and parental care coevolve in fishes?
Authors: Kolm N. , Ahnesjö I.
Published: July 2005

A phenomenon that has attracted a substantial theoretical and empirical interest is the positive relationship between egg size and the extent of parental care in fishes. Interestingly, despite the effort put into solving the causality behind this relationship over the past two decades it remains largely unsolved. Moreover, how general the positive relationship between egg size and parental care is among fishes is also poorly understood. In order to stimulate research exploring egg size and parental care variation in fishes, the potential selective forces from both natural and sexual selection on egg size and parental care are discussed. Recent empirical findings on how oxygen requirements and developmental times may differ between differently sized eggs are incorporated into a critical view of the current theory of this field. Furthermore, it is suggested that the up to now neglected effects of sexual selection, through both mate choice and sexual conflict, can have strong effects on the relationship between egg size and parental care in fishes. In light of the recent developments of comparative and experimental methods, future approaches that may improve the understanding of the relationship between egg size and care in fishes are suggested.
Phylogeny of earwigs (Insecta: Dermaptera) based on molecular and morphological evidence: reconsidering the classification of Dermaptera
Authors: Jarvis Karl J. , Haas Fabian , Whiting Michael F.
Published: July 2005

Abstract.  Dermaptera (earwigs) is a cosmopolitan order of insects, the phylogenetic relationships of which are poorly understood. The phylogeny of Dermaptera was inferred from large subunit ribosomal (28S), small subunit ribosomal (18S), histone‐3 (H3) nuclear DNA sequences, and forty‐three morphological characters. Sequence data were collected for thirty‐two earwig exemplar taxa representing eight families in two suborders: Hemimeridae (suborder Hemimerina); Pygidicranidae, Anisolabididae, Labiduridae, Apachyidae, Spongiphoridae, Chelisochidae and Forficulidae (suborder Forficulina). Eighteen taxa from ten additional orders were also included, representing Ephemeroptera, Odonata, Orthoptera, Phasmida, Embiidina, Mantodea, Isoptera, Blattaria, Grylloblattodea and Zoraptera. These data were analysed via direct optimization in poy under a range of gap and substitution values to test the sensitivity of the data to variations in parameter values. These results indicate that the epizoic Hemimerus is not sister to the remaining Dermaptera, but rather nested as sister to Forficulidae + Chelisochidae. These analyses support the paraphyly of Pygidicranidae and Spongiphoridae and the monophyly of Chelisochidae, Forficulidae, Anisolabididae and Labiduridae.
Phylogenetic analysis of the Abana group of genera (Hemiptera: Cicadellidae: Cicadellinae: Proconiini)
Authors: Ceotto Paula C. , Mejdalani Gabriel
Published: July 2005

Abstract.  The Abana group sensu Mejdalani (2000) includes the genera Abana Distant, Acrobelus Stål, Acrogonia Stål, Deselvana Young, Omagua Melichar, Raphirhinus de LaPorte and Teletusa Distant. A comparative morphological study of these genera and six outgroup taxa yielded seventy‐four characters of the head, thorax, and male and female genitalia. The structures of the female genitalia, studied for the first time in a phylogenetic analysis of proconiine genera, provided informative characters for the analysis. A phylogenetic analysis conducted to estimate the relationships among these genera, using six outgroup genera, revealed eight equally most‐parsimonious trees. Goloboff's implied weights method resulted in two trees and successive weighting selected one of the original trees. The latter shows the following relationships for the genera: (Cicciana ((Acrogonia, Homalodisca) (Molomea, Tretogonia)) (Diestostemma (Desamera (Acrobelus ((Abana, Omagua) ((Raphirhinus (Deselvana sp., Deselvana ornata, Deselvana excavata)) (Deselvana dorsivitta, Teletusa))))))). The monophyly of the Abana group was not recovered, but a monophyletic group including Abana, Acrobelus, Deselvana, Omagua, Raphirhinus and Teletusa appeared in all eight trees. The genus Deselvana seems to be polyphyletic.
Phylogenetic placement of Arrowinini trib.n. within the subfamily Staphylininae (Coleoptera: Staphylinidae), with revision of the relict South African genusArrowinusand description of its larva
Authors: Solodovnikov Alexey YU. , Newton Alfred F.
Published: July 2005

Abstract. The rove beetle genusArrowinus, a flightless endemic of South Africa, is revised.Arrowinus phaenomenalisBernhauer, the type species of the genus, is redescribed based on an examination of type and additional material. Three new species,A. relictussp.n.,A. peckorumsp.n.andA. minutussp.n., are described. For all four species, an identification key for adults and larvae is provided, along with available data on their distribution and bionomics. Phylogenetic relationships among the four species ofArrowinuswere sought by means of a cladistic analysis. Based on the presumed larvae ofA. peckorumand other species of the genus (identified by association with the respective adults), the first larval description forArrowinusis provided. By means of a cladistic analysis of morphological characters of both adults and larvae, analysed separately and in combination, the phylogenetic relationships ofArrowinuswith other members of the subfamily Staphylininae were revealed and are discussed. To facilitate this discussion, current problems of phylogeny and systematics are summarized for all Staphylininae. In agreement with an earlier hypothesis, the analysis confirmed thatArrowinusdoes not belong to the subtribe Quediina of the tribe Staphylinini (where it has hitherto resided) but constitutes a separate taxon, sister to the tribe Staphylinini, for which a new tribe Arrowinini is established. The analysis provides support for the monophyly of the tribe Staphylinini, the subfamily Staphylininae, and the clade (Staphylininae + Paederinae). Adult and larval identification keys to all tribes of Staphylininae are provided.
Phylogeny, systematics and evolution of mimetic wing patterns of Eterusia moths (Lepidoptera, Zygaenidae, Chalcosiinae)
Authors: Yen Shen‐Horn , Robinson Gaden S. , Quicke Donald L. J.
Published: July 2005

Abstract.  The aim of the present study was to investigate the phylogeny, systematics and evolution of the mimetic wing patterns of Eterusia, a day‐flying moth genus that exhibits great morphological diversity, as well as the highest insular differentiation in eastern Asia and which has the most chaotic taxonomic history in the family Zygaenidae. We examined the wing patterns of the insects involved using visible and ultraviolet light (both reflectance and fluorescence). The phylogeny of thirty‐four taxa, including all the recognized species of Eterusia plus two species of Soritia as outgroups, was reconstructed based on eighty adult morphological characters, including forty‐one derived from colour patterns. Phylogenetic relationships based on the whole dataset revealed that (1) the most current concept of Eterusia is monophyletic, and (2) different types of mimetic pattern show different levels of phylogenetic conservation. To investigate the evolution of their colour patterns we inactivated all the relevant characters and reconstructed another phylogeny, which was found to differ significantly from the one based on the whole character set in the position of the E. risa species group. We used these phylogenetic hypotheses to test evolutionary predictions based on conventional Müllerian mimicry and quasi‐Batesian mimicry dynamics. The results of permutation–tail–probability tests showed that the coloration characters are phylogenetically conserved, thus justifying a Müllerian interpretation. However, when comparing the observed topologies with hypothetical trees constrained to fit perfect Müllerian or quasi‐Batesian scenarios using the Kishino–Hasegawa test, the observed phylogenies were more consistent with the phylogenetic prediction of quasi‐Batesian mimicry. Therefore, we consider that applying these two phylogenetic methods to justify mimicry models may not always be practical. Finally, the taxonomy of Eterusia is revised. In total, two new species (E. austrochinensis, E. guanxiana), one new subspecies (E. risa palawanica) and four new synonyms (E. lativitta and E. fasciata of E. sublutea, E. coelestina of E. subcyanea, E. angustipennis gaedei of E. angustipennis angustipennis) are established.
Orphan transcripts in Arabidopsis thaliana: identification of several hundred previously unrecognized genes
Authors: Riaño‐Pachón Diego Mauricio , Dreyer Ingo , Mueller‐Roeber Bernd
Published: July 2005

Expressed sequence tags (ESTs) represent a huge resource for the discovery of previously unknown genetic information and functional genome assignment. In this study we screened a collection of 178 292 ESTs from Arabidopsis thaliana by testing them against previously annotated genes of the Arabidopsis genome. We identified several hundreds of new transcripts that match the Arabidopsis genome at so far unassigned loci. The transcriptional activity of these loci was independently confirmed by comparison with the Salk Whole Genome Array Data. To a large extent, the newly identified transcriptionally active genomic regions do not encode ‘classic’ proteins, but instead generate non‐coding RNAs and/or small peptide‐coding RNAs of presently unknown biological function. More than 560 transcripts identified in this study are not represented by the Affymetrix GeneChip arrays currently widely used for expression profiling in A. thaliana. Our data strongly support the hypothesis that numerous previously unknown genes exist in the Arabidopsis genome.
ERECTA receptor‐like kinase and heterotrimeric G protein from Arabidopsis are required for resistance to the necrotrophic fungus Plectosphaerella cucumerina
Authors: Llorente Francisco , Alonso‐Blanco Carlos , Sánchez‐Rodriguez Clara , Jorda Lucía , Molina Antonio
Published: July 2005

Arabidopsis resistance to the necrotrophic fungus Plectosphaerella cucumerina is complex and depends on the ethylene, jasmonic acid and salicylic acid signaling pathways. A quantitative trait loci (QTL) analysis of resistance to this fungus was performed using two populations of recombinant inbred lines. Three loci QRP1‐QRP3 (for Quantitative Resistance to Plectosphaerella) were identified and mapped on chromosome 2 (QRP1 and QRP2) and 5 (QRP3). QRP1, the locus showing the strongest effect, was found to correspond to the ERECTA (ER) gene that encodes a receptor‐like‐kinase (RLK), which has been previously implicated in plant development, and resistance to the bacterium Ralstonia solanacearum. The leucine‐rich repeat and the kinase domains of ERECTA were specifically required for resistance to P. cucumerina, as er mutant alleles impaired in any of these domains showed enhanced susceptibility to this fungus, but not to other virulent pathogens. The involvement of the ER‐signaling pathway in resistance to P. cucumerina was supported by the fact that three mutants defective in this pathway, elk2, elk5 and elk4 (agb1‐1), which encodes the β‐subunit of Arabidopsis heterotrimeric G protein, were also impaired in their resistance to this fungus. The putative function of the Arabidopsis heterotrimeric G protein in resistance to P. cucumerina suggested by the enhanced susceptibility of agb1‐1 was corroborated by the demonstration that a null allele (gpa1‐4) of the G protein α‐subunit showed enhanced resistance to this pathogen. Deposition of β‐1,3‐glucan callose at infection sites was specifically impaired in er‐1 and agb1‐1 mutants upon P. cucumerina inoculation. Taken together, these data suggest a putative function of ERECTA and heterotrimeric G protein in P. cucumerina perception.
Altered microtubule dynamics by expression of modified α‐tubulin protein causes right‐handed helical growth in transgenic Arabidopsis plants
Authors: Abe Tatsuya , Hashimoto Takashi
Published: July 2005

The proper organization of cortical microtubule arrays is essential for anisotropic growth in plants but how distinct array patterns are formed is not understood. Here, we report a relationship between microtubule dynamics and array organization using transgenic plants expressing modified tubulins. When green fluorescent protein (GFP) or a hemaglutinin epitope tag was fused to the N‐terminus of tubulins and expressed in Arabidopsis plants, these tubulins were incorporated into microtubules along with endogenous tubulins. Plants expressing the modified β‐tubulins were phenotypically normal and possessed transversely oriented cortical arrays in the epidermal cells of the root elongation zone; however, the expression of modified α‐tubulins caused right‐handed helical growth, increased trichome branching, and a shallow left‐handed (S‐form) helical array organization. In cells expressing the modified α‐tubulins, microtubule dynamicity was suppressed and polymerization was promoted, and GFP‐EB1 (End Binding 1) labeled larger regions of the microtubule end more frequently, when compared with control cells. We propose that the N‐terminal appendage introduced into α‐tubulin inhibits GTP hydrolysis, thus producing polymerization‐prone microtubules with an extended GTP cap. Consistent with this interpretation, plants expressing an α‐tubulin mutated in the GTPase‐activating domain exhibited similar microtubule properties, with regard to dynamics and the localization of GFP‐EB1, and showed right‐handed helical growth.
Cell wall extension results in the coordinate separation of parallel microfibrils: evidence from scanning electron microscopy and atomic force microscopy
Authors: Marga Francoise , Grandbois Michel , Cosgrove Daniel J. , Baskin Tobias I.
Published: July 2005

Enlargement of the cell wall requires separation of cellulose microfibrils, mediated by proteins such as expansin; according to the multi‐net growth hypothesis, enlargement passively reorients microfibrils. However, at the molecular scale, little is known about the specific movement of microfibrils. To find out, we examined directly changes in microfibril orientation when walls were extended slowly in vitro under constant load (creep). Frozen‐thawed cucumber hypocotyl segments were strained by 20–30% by incubation in pH 4.5 buffer or by incubation of heat‐inactivated segments in α‐expansin or a fungal endoglucanase (Cel12A). Subsequently, the innermost layer of the cell wall was imaged, with neither extraction nor homogenization, by field‐emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). AFM images revealed that sample preparation for FESEM did not appreciably alter cell wall ultrastructure. In both FESEM and AFM, images from extended and non‐extended samples appeared indistinguishable. To quantify orientational order, we used a novel algorithm to characterize the fast Fourier transform of the image as a function of spatial frequency. For both FESEM and AFM images, the transforms of non‐extended samples were indistinguishable from those of samples extended by α‐expansin or Cel12A, as were AFM images of samples extended by acidic buffer. We conclude that cell walls in vitro can extend slowly by a creep mechanism without passive reorientation of innermost microfibrils, implying that wall loosening agents act selectively on the cross‐linking polymers between parallel microfibrils, rather than more generally on the wall matrix.
Interaction of Arabidopsis BRASSINOSTEROID‐INSENSITIVE 1 receptor kinase with a homolog of mammalian TGF‐β receptor interacting protein
Authors: Ehsan Hashimul , Ray William Keith , Phinney Brett , Wang Xiaofeng , Huber Steven C. , Clouse Steven D.
Published: July 2005

Brassinosteroids (BRs) regulate multiple aspects of plant growth and development and require an active BRASSINOSTEROID‐INSENSITIVE 1 (BRI1) receptor serine/threonine kinase for hormone perception and signal transduction. In mammals, the transforming growth factor‐beta (TGF‐β) family of polypeptides modulate numerous aspects of development and are perceived at the cell surface by a complex of type I and type II TGF‐β receptor serine/threonine kinases. TGF‐β receptor interacting protein (TRIP‐1) is a cytoplasmic substrate of the TGF‐β type II receptor kinase and plays a role in TGF‐β signaling. TRIP‐1 is a WD domain protein that also functions as an essential subunit of the eIF3 eukaryotic translation initiation factor in animals, yeast and plants. We previously cloned putative TRIP‐1 homologs from bean and Arabidopsis and found that transgenic Arabidopsis plants expressing antisense TRIP‐1 RNA exhibited a broad range of developmental defects including some morphological characteristics that resemble the phenotype of BR‐deficient and ‐insensitive mutants. We now show that the BRI1 kinase domain phosphorylates Arabidopsis TRIP‐1 on three specific sites in vitro (Thr‐14, Thr‐89 and either Thr‐197 or Ser‐198). Co‐immunoprecipitation experiments using antibodies against TRIP‐1, BRI1 and various fusion proteins strongly suggest that TRIP‐1 and BRI1 also interact directly in vivo. These findings support a role for TRIP‐1 in the molecular mechanisms of BR‐regulated plant growth and development, possibly as a cytoplasmic substrate of the BRI1 receptor kinase.
Heat shock protein 90 and its co‐chaperone protein phosphatase 5 interact with distinct regions of the tomato I‐2 disease resistance protein
Authors: De La Fuente Bentem van Sergio , Vossen Jack H. , de Vries Klaas Jan , van Wees Saskia , Tameling Wladimir I.L. , Dekker Henk L. , de Koster Chris G. , Haring Michel A. , Takken Frank L.W. , Cornelissen Ben J.C.
Published: July 2005

Recent data suggest that plant disease resistance (R) proteins are present in multi‐protein complexes. Tomato R protein I‐2 confers resistance against the fungal pathogen Fusarium oxysporum. To identify components of the I‐2 complex, we performed yeast two‐hybrid screens using the I‐2 leucine‐rich repeat (LRR) domain as bait, and identified protein phosphatase 5 (PP5) as an I‐2 interactor. Subsequent screens revealed two members of the cytosolic heat shock protein 90 (HSP90) family as interactors of PP5. By performing in vitro protein–protein interaction analysis using recombinant proteins, we were able to show a direct interaction between I‐2 and PP5, and between I‐2 and HSP90. The N‐terminal part of the LRR domain was found to interact with HSP90, whereas the C‐terminal part bound to PP5. The specific binding of HSP90 to the N‐terminal region of the I‐2 LRR domain was confirmed by co‐purifying HSP90 from tomato lysate using recombinant proteins. Similarly, the interaction between PP5 and HSP90 was established. To investigate the role of PP5 and HSP90 for I‐2 function, virus‐induced gene silencing was performed in Nicotiana benthamiana. Silencing of HSP90 but not of PP5 completely blocked cell death triggered by I‐2, showing that HSP90 is required for I‐2 function. Together these data suggest that R proteins require, like steroid hormone receptors in animal systems, an HSP90/PP5 complex for their folding and functioning.
Siderophore‐mediated upregulation of Arabidopsis ferritin expression in response to Erwinia chrysanthemi infection
Authors: Dellagi Alia , Rigault Martine , Segond Diego , Roux Camille , Kraepiel Yvan , Cellier Françoise , Briat Jean‐François , Gaymard Frédéric , Expert Dominique
Published: July 2005

Ferritins are multimeric iron storage proteins encoded by a four‐member gene family in Arabidopsis (AtFer1–4). To investigate whether iron sequestration in ferritins is a part of an iron‐withholding defense system induced in response to bacterial invasion, we used Arabidopsis thaliana as a susceptible host for the pathogenic bacterium Erwinia chrysanthemi. In this study, we used a T‐DNA insertion mutant line to show that the lack of a functional AtFer1 gene resulted in an enhanced susceptibility of Arabidopsis plants to E. chrysanthemi. We found that the AtFer1 gene is upregulated during infection, with a biphasic accumulation of the transcript at critical time points 0.5 and 24 h post‐infection (p.i.). The activation of AtFer1 expression observed at 24 h p.i. was independent of the iron‐dependent regulatory sequence (IDRS) known to mediate the transcriptional response of the AtFer1 gene to iron excess and to nitric oxide. Upregulation of AtFer1 gene expression was compromised after inoculation with an E. chrysanthemi siderophore null mutant. Infiltration of the purified siderophores chrysobactin and desferrioxamine strongly increased AtFer1 transcript abundance and it did not occur with the iron‐loaded forms of these siderophores. We found that neither oxidative stress nor nitric oxide was involved in the plant response to chrysobactin. Our data show that ferritin accumulation during infection of Arabidopsis by E. chrysanthemi is a basal defense mechanism which is mainly activated by bacterial siderophores. The potential role of siderophores in this process is discussed.
Disruption of the cellulose synthase gene, AtCesA8/IRX1, enhances drought and osmotic stress tolerance in Arabidopsis
Authors: Chen Zhizhong , Hong Xuhui , Zhang Hairong , Wang Youqun , Li Xia , Zhu Jian‐Kang , Gong Zhizhong
Published: July 2005

Two allelic Arabidopsis mutants, leaf wilting 2‐1 and leaf wilting 2‐2 (lew2‐1 and lew2‐2 ), were isolated in a screen for plants with altered drought stress responses. The mutants were more tolerant to drought stress as well as to NaCl, mannitol and other osmotic stresses. lew2 mutant plants accumulated more abscisic acid (ABA), proline and soluble sugars than the wild type. The expression of a stress‐inducible marker gene RD29A, a proline synthesis‐related gene P5CS (pyrroline‐5‐carboxylate synthase) and an ABA synthesis‐related gene SDR1 (alcohol dehydrogenase/reductase) was higher in lew2 than in the wild type. Map‐based cloning revealed that the lew2 mutants are new alleles of the AtCesA8/IRX1 gene which encodes a subunit of a cellulose synthesis complex. Our results suggest that cellulose synthesis is important for drought and osmotic stress responses including drought induction of gene expression.
Potential impacts of climate change on the distributions of several common and rare freshwater fishes in Canada
Authors: Chu Cindy , Mandrak Nicholas E. , Minns Charles K.
Published: July 2005

Climate change will ultimately affect the supply and quality of freshwater lakes and rivers throughout the world. This study examines the potential impacts of climate change on freshwater fish distributions in Canada. Climate normals data (means from 1961 to 1990) from Environment Canada were used to map current climate found throughout the tertiary watersheds of Canada. Logistic regressions based on these climate data were used to develop predictive presence‐absence equations for (a) common commercially and recreationally important species and (b) an Arctic freshwater species and a freshwater fish species of conservation significance listed by the Committee on the Status of Endangered Wildlife (COSEWIC). The Canadian Centre for Climate Modelling and Analysis Global Coupled Model 2(IS92a) provided forecasts of Canada's climate in 2020 and 2050. The data from this scenario and the logistic regressions provided a ready framework for predicting the potential distributions of the fishes. Physical and ecological barriers would have to be overcome for the distribution of these species to actually change in response to climate change. Generally, coldwater species may be extirpated from much of their present range while cool and warm‐water species may expand northward. Species that are limited to the most southern regions of the country may expand northwards. A conceptual framework for assessing potential climate change impacts on fishes and the variety of management strategies required to deal with these impacts are discussed. Our forecasts demonstrate the need for climate change assessments in species at risk as well as for common species.
Dispersal and establishment: spatial patterns and species–area relationships
Authors: Hovestadt Thomas , Poethke Hans Joachim
Published: July 2005

According to the equilibrium theory of island biogeography, high colonization ability of species is associated with low exponents (z) of the species–area relationship (SAR) and weak spatial patterns in species number and dissimilarity. However, the relationship betweenzand the strength of these spatial patterns has not been investigated systematically. We used a multispecies metapopulation model to investigate these relationships in an archipelago of islands. We conclude that this relationship can only be predicted if either the dispersal ability or the power of establishment of species is known. With species richness limited by establishment, we generated highz‐values associated with weak spatial patterns in species number and dissimilarity. If species richness was constrained by the dispersal ability of species, we observed low to mediumz‐values but strong spatial patterns. If the dispersal ability and the abilities of species to establish were both high,z‐values and spatial pattern tend to be low and species numbers were limited by the size of the regional species pool.
Invasive alien plant species in China: regional distribution patterns
Authors: Liu Jian , Liang Shi‐Chu , Liu Feng‐Hong , Wang Ren‐Qing , Dong Ming
Published: July 2005

Plant invasions have been attracting increasing attention from ecologists because of their worldwide environmental impacts and huge economic costs. Research on the characteristics of the recipient regions is essential for understanding the process of plant invasion. However, few previous studies on invasibility of habitats include social factors, although human activities are critical in the process of plant invasion. China is a vast country with high plant species diversity and a long history of introduction of exotic plant species and is particularly vulnerable to invasive plant species. Alien plant species are widespread in the country. Therefore, the study of invasive plants in China is urgent in practice and theoretically important for developing invasion ecology. For the present study, 126 species were selected to represent the major invasive plant species in China. We then collected data on their species richness in 31 provincial administrative units of China and performed Spearman rank correlations between species richness and possible natural and socio‐economic factors. We found that socio‐economic factors, such as human density and GDP, correlated positively with the species richness of invasive plants in China. In conjunction with the natural and socio‐economic correlations in the study of regional distribution pattern of the major invasive plants, we discussed the factors influencing the regional distribution pattern of the major invasive plants in China. We suggest that native plant species richness was mainly determined by the natural conditions of the regions, while invasive species richness was influenced by natural conditions and human disturbance together.
Profiling invasive fish species: the importance of phylogeny and human use
Authors: Alcaraz Carles , Vila‐Gispert Anna , García‐Berthou Emili
Published: July 2005

Understanding the ecological differences between native and invasive species is of considerable scientific and practical interest. We examined such differences between native and invasive inland fish species from the Iberian Peninsula in order to analyse the importance of phylogenetic correction and variability (in addition to central tendency). We collected 26 quantitative and qualitative variables on the ecology, life‐history traits and human use of the 69 inland fish species of the Iberian Peninsula, including native, invasive and migratory species. The taxonomic distribution of invasive fish species deviated significantly from world freshwater richness and in contrast to native species, invasive fish belongs to only five taxonomic orders but to a wide spectrum of families not native to the Iberian Peninsula. Because the life‐history traits were highly dependent on taxonomy, the results, with or without applying phylogenetic methods, differed and after accounting for phylogeny, invasive species displayed higher and wider latitude in general and a different reproductive season mainly among salmonids and cyprinids. Human use was also significantly different between native and invasive fish species and produced more variability in life‐history traits of invasive species and uneven taxonomic distribution because of the high diversity of species introduced. We show that accounting for taxonomy and studying variability in addition to central tendency is important in the comparison of life‐history traits between native and invasive species.
Borosilicate‐ and phengite‐bearing veins from the Grenville Province of Labrador: evidence for rapid uplift
Authors: KORHONEN F. J. , STOUT J. H.
Published: July 2005

Quartzo‐feldspathic veins emplaced within a migmatite terrane near Wilson Lake in the Grenville Province of central Labrador record a metamorphic event not evident in the host rocks. The discordant veins are undeformed and have undisturbed primary igneous/hydrothermal textures. Most of the veins contain euhedral kyanite, as well as aggregates of kyanite, K‐feldspar, phlogopite and minor dumortierite which are likely pseudomorphs after primary phengite. The reconstructed phengite compositions range from 3.1 to 3.2 Si per 11 oxygen formula unit. The pseudomorph assemblage is interpreted as the product of phengite + quartz melting under H2O‐undersaturated conditions, which brackets P–T conditions of formation to about 9–16 kbar and 775–875 °C. A parallel vein that is likely of the same generation contains the borosilicate phases, dumortierite, prismatine and grandidierite, but no kyanite. The borosilicate assemblages constrain the P–T conditions of vein crystallization to ≥10 kbar and c. 750–850 °C. Vein emplacement is constrained to T ≤ 875 °C at the same pressures, which is well within the kyanite zone.

Because the host rocks and veins must have experienced the same P–T history following vein emplacement, the presence of unreacted sillimanite in the host migmatites implies insufficient time for host rock equilibration. Slow reaction rates because of anhydrous conditions are not a likely explanation given the abundance of biotite and hornblende in the host rocks. The ductility implied by the breakdown of a hydrous phase (phengite) and the production of an H2O‐undersaturated melt in the veins contrasts with the apparently brittle behaviour of the host rocks. The absence of deformation since the time of vein emplacement, even at temperatures above 750 °C, suggests that the deep crust in this part of Labrador had a very short residence time under conditions of the kyanite zone. Rapid decompression from those conditions is consistent with quartz + phengite melting and accounts for the relatively brittle behaviour of the terrane as it was uplifted.
Progress of actinolite‐forming reactions in mafic schists during retrograde metamorphism: an example from the Sanbagawa metamorphic belt in central Shikoku, Japan
Authors: OKAMOTO A. , TORIUMI M.
Published: July 2005

Hydration reactions are direct evidence of fluid–rock interaction during regional metamorphism. In this study, hydration reactions to produce retrograde actinolite in mafic schists are investigated to evaluate the controlling factors on the reaction progress. Mafic schists in the Sanbagawa belt contain amphibole coexisting with epidote, chlorite, plagioclase and quartz. Amphibole typically shows two types of compositional zoning from core to rim: barroisite → hornblende → actinolite in the high‐grade zone, and winchite → actinolite in the low‐grade zone. Both types indicate that amphibole grew during the exhumation stage of the metamorphic belt. Microstructures of amphibole zoning and mass‐balance relations suggest that: (1) the actinolite‐forming reactions proceeded at the expense of the preexisting amphibole; and (2) the breakdown reaction of hornblende consumed more H2O fluid than that of winchite, when one mole of preexisting amphibole was reacted. Reaction progress is indicated by the volume fraction of actinolite to total amphibole, Yact, with the following details: (1) reaction proceeded homogeneously in each mafic layer; (2) the extent of the hornblende breakdown reaction is commonly low (Yact < 0.5), but it increases drastically in the high‐grade part of the garnet zone (Yact > 0.7); and (3) the extent of the winchite breakdown reaction is commonly high (Yact > 0.7). Many microcracks are observed within hornblende, and the extent of hornblende breakdown reaction is correlated with the size reduction of the hornblende core. Brittle fracturing of hornblende may have enhanced retrograde reaction progress by increasing of influx of H2O and the surface area of hornblende. In contrast to high‐grade rocks, the winchite breakdown reaction is well advanced in the low‐grade rocks, where reaction progress is not associated with brittle fracturing of winchite. The high extent of the reaction in the low‐grade rocks may be due to small size of winchite before the reaction.