bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mycorrhizal vs saprotrophic status of fungi: the isotopic evidence
Authors: Hobbie Erik A. , Weber Nancy S. , Trappe James M. 
Published: March 2003

Summary Relative abundances of carbon and nitrogen isotopes in fungal sporocarps are useful in assessing mycorrhizal or saprotrophic status, and might provide insights into the evolutionary history of these traits. Sporocarps of known mycorrhizal or saprotrophic genera were collected at Woods Creek, OR, USA, and isotopically compared with foliage, litter, soils and wood collected from the same site. Possible trophic strategies were then isotopically assessed in archived specimens of the Pezizales of known molecular phylogeny from the western United States. At Woods Creek, mycorrhizal fungi were 3.5‰ ± 0.6‰ depleted in δ13C and 5.7‰ ± 0.4‰ enriched in δ15N compared with saprotrophic fungi. By contrast, fungi from four genera of uncertain mycorrhizal status (Clavulina,Helvella,Otidia, andRamaria) were only 0.4‰ ± 0.4‰ enriched in δ13C and 1.2‰ ± 1.1‰ depleted in δ15N relative to mycorrhizal fungi. In archived samples, the δ13C measurements appeared to be a better indicator of trophic strategy than δ15N measurements. The δ13C measurements suggested that mycorrhizal or saprotrophic status was conserved within families of the Pezizales (as determined by molecular phylogeny), with the Helvellaceae and Tuberaceae mycorrhizal and Discinaceae and Morchellaceae being largely saprotrophic.
Analysis of arbuscular mycorrhizas using symbiosis‐defective plant mutants
Authors: Marsh John F. , Schultze Michael 
Published: March 2003

SummaryArbuscular mycorrhizas (AM), mutualistic plant–fungus symbioses formed on the majority of land plants, appear to play an important role in plant mineral nutrition, plant health, and might influence the structure of plant communities. Progress in understanding the genetic and molecular basis of this important symbiotic association has been hampered by the obligate biotrophy of the fungal partner, and by the lack of mycorrhiza formation on the plant model species Arabidopsis thaliana. Recently, legume plants, such as Medicago truncatula and Lotus japonicus, have been chosen as experimental systems for research of plant–microbe symbioses. The application of both reverse‐ and traditional forward‐genetic approaches, in conjunction with genomics initiatives in model legumes, will rapidly increase our understanding of the plant‐encoded genetic determinants of the arbuscular mycorrhiza. An essential step in this process has been the generation, isolation and analysis of mycorrhizal mutants. This review provides an introduction to existing plant mutants affected in AM formation.
UV and blue light signalling: pathways regulating chalcone synthase gene expression in Arabidopsis
Authors: Jenkins Gareth I. , Long Joanne C. , Wade Helena K. , Shenton Matthew R. , Bibikova Tatiana N. 
Published: March 2003

SummaryUV‐B, UV‐A and blue light control a variety of aspects of plant development via distinct photoreceptors and signalling pathways. The known photoreceptors for UV‐A/blue light are cryptochrome (cry)1 and cry2, and the phototropism photoreceptor, phototropin. Redox processes are important in cry and phototropin signal transduction. A specific photoreceptor for UV‐B has not been identified and there appear to be several possible UV‐B signalling pathways. We are investigating the UV and blue light regulation of transcription of the chalcone synthase gene (CHS) in Arabidopsis. Experiments with photoreceptor mutants show that distinct UV‐A/blue (cry mediated) and UV‐B photoreception systems control CHS expression. Experiments with an Arabidopsis cell suspension culture show that the UV‐B and cry1 signalling pathways differ kinetically and pharmacologically. In contrast to some other UV‐B responses, the UV‐B induction of CHS does not appear to involve oxidative stress signalling. Promoter elements and candidate transcription factors that effect CHS induction have been identified. Interactions within a network of UV‐B, cry and phytochrome signalling pathways regulate CHS expression. Synergistic interactions between the UV‐B pathway and distinct UV‐A and blue‐light pathways maximize the response. In addition, specific phytochromes positively control the cry1 pathway via distinct potentiation and coaction effects, and negatively regulate the UV‐B pathway.
Calcium‐based signalling systems in guard cells
Authors: Ng CarL. K.‐Y. , Mcainsh Martin R. , Gray Julie E. , Hunt LeE. , Leckie Calum P. , Mills Lewis , Hetherington Alistair M. 
Published: March 2003

SummaryCalcium is a ubiquitous intracellular signal responsible for controlling numerous cellular processes in both plants and animals. As an example, Ca2+ has been shown to be a second messenger in the signal transduction pathways by which stomatal guard cells respond to external stimuli. Regulated increases in the cytosolic concentration of free calcium ions ([Ca2+]cyt) in guard cells have been observed to be a common intermediate in many of the pathways leading to either opening or closing of the stomatal pore. This observation has prompted investigations into how specificity is encoded in the Ca2+ signal. It has been suggested that the key to generating stimulus‐specific calcium signatures lies in the ability to access differentially the cellular machinery controlling calcium influx and release from intracellular stores. Several important components of the calcium‐based signalling pathways have been identified in guard cells including cADPR, phospholipase C–InsP3, InsP6 and H2O2. These data suggest that the pathways for intracellular mobilization of Ca2+ are evolutionarily conserved between plants and animals.AbbreviationsABA, abscisic acid; [Ca2+]cyt, cytosolic free calcium concentration; [Ca2+]ext, external calcium concentration; IK,in; inward‐rectifying K+ currents; InsP3, inositol‐1,4,5‐trisphosphate; InsP6, inositol hexakisphosphate; PLC, phospholipase C; PLD, phospholipase D; PA, phosphatidic acid; H2O2, hydrogen peroxide; AAPK, ABA‐activated serine‐threonine protein kinase; cADPR, cyclic adenosine 5′‐diphosphoribose; U73122, 1‐(6‐{[17â‐3‐methoxyestra‐1,3,5(10)‐trien‐17‐yl]amino}hexyl)‐1H‐pyrrole‐2, 5‐dione; RyR; ryanodine receptor; CICR; calcium‐induced calcium‐release; ICa, inward calcium current.
Composted recycled organic matter suppresses soil‐borne diseases of field crops
Authors: Tilston E. L. , Pitt D. , Groenhof A. C. 
Published: March 2003

Summary• Suppression of soil‐borne diseases of horticultural crops by composts has been attributed to the activities of antagonistic microorganisms. The potential for abiotic disease suppression in field‐grown crops was explored using glasshouse‐based bio‐assays for five pathogens of agricultural crops and eight formulations of recycled organic matter compost.• The effects of compost formulation and postmaturation processing were investigated by comparing disease severity on recycled organic matter composts with a commercial seedling compost. Comparisons were made within native and autoclaved series of composts. Autoclaving perturbed compost chemistry without the addition of other materials.• The severity of autoclaving‐induced changes to compost chemistry were related to formulation and processing issues. Extractable carbon content, nitrate‐N content and pH all contributed to the suppressive capacity of recycled organic matter composts. There may also be a biotic component to the suppression observed.• For each pathogen the influential chemical characteristics of suppressive composts were the same as those identified for soils in other studies. There is potential for the suppressive capacity of recycled organic matter composts to be improved.
Developmental shifts in watermelon growth and reproduction caused by the squash bug, Anasa tristis
Authors: Biernacki Maciej , Lovett‐Doust Jon 
Published: March 2003

Summary

Compared with leaf‐feeding herbivores, little is known about how sap‐feeding herbivores affect plant growth, morphology and reproduction. This study examines effects of the sap‐feeding squash bug ( Anasa tristis
) on watermelon (
Citrullus lanatus ) root, leaf and reproductive structures.
Plants at the four‐leaf stage were exposed to different densities of caged squash bugs for 67 d (to plant maturity).
Initial effects were on roots. Herbivory was associated with a significant reduction in mean total root length, root surface area and number of root tips, as well as an increase in root diameters. Herbivore‐exposed plants had significantly more leaves, although leaf lifespan was decreased. Both total plant dry mass and fruit dry mass per unit leaf area were significantly greater in controls. Significant effects of herbivores on plant reproductive traits included delayed flower formation (by 7–12 d), change in floral sex ratio (in favor of femaleness), increased fruit abortion, and smaller fruit size.
Developmental consequences were related to changes in plant water relations, including decreased water‐use efficiency. Water use in treated plants was three to nine times greater per unit of plant dry mass than in controls.
Ecology and evolution of light‐dependent and light‐independent phytogenic volatile organic carbon
Authors: Lerdau Manuel , Gray Dennis 
Published: March 2003

SummaryThe low molecular weight hydrocarbons produced by plants form a uniquely exciting group of compounds. Produced by a common biosynthetic route, they play multiple and complex roles in organismal, ecological, and atmospheric processes. While some of these compounds have clearly identified functions within plants, others are made for reasons not yet fully understood. Here, both light‐dependent and light‐independent emissions are reviewed, together with regulation of production and possible functions of light‐dependent volatile organic carbon (VOC). In addition to issues regarding the phylogenetic origins of VOC emissions, the origins of the pivotal enzymes that give rise to the observed emission phenotypes are discussed. Studies on the evolution and regulation of their production and emission provide an amazing opportunity for scientists working from the molecular to the tropospheric scales to interact.

Contents

Summary
199

I.
Introduction
199

II.
Light‐independent emissions
200

III.
Light‐dependent emissions
201

IV.
Regulation of production
202

V.
Possible functions of light‐dependent VOCs
204

VI.
Evolutionary aspects of phytogenic VOC
206

Acknowledgements
206

References
209
Source–sink balance and carbon allocation below ground in plants exposed to ozone
Authors: Andersen Christian P. 
Published: March 2003

SummaryThe role of tropospheric ozone in altering plant growth and development has been the subject of thousands of publications over the last several decades. Still, there is limited understanding regarding the possible effects of ozone on soil processes. In this review, the effects of ozone are discussed using the flow of carbon from the atmosphere, through the plant to soils, and back to the atmosphere as a framework. A conceptual model based on carbohydrate signaling is used to illustrate physiological changes in response to ozone, and to discuss possible feedbacks that may occur. Despite past emphasis on above‐ground effects, ozone has the potential to alter below‐ground processes and hence ecosystem characteristics in ways that are not currently being considered.ContentsSummary213I.Introduction213II.Source–sink model: carbohydrate signaling214III.Effect of ozone on above‐ground sources and sinks216IV.Decreased allocation below ground218V.Carbon flux to soils220VI.Soil food web223VII.Summary, conclusions and future research223Acknowledgements223References223
Phytochrome‐hormonal signalling networks
Authors: Halliday Karen J. , Fankhauser Christian 
Published: March 2003

SummaryThrough time, plants have evolved an extraordinary ability to interpret environmental cues. One of the most reliable of these cues is light, and plants are particularly adept at sensing and translating environmental light signals. The phytochrome family of photoreceptors monitor cues such as daylength or vegetative shade and adjust development to reflect change in these parameters. Indeed, it is their ability to coordinate these complex developmental changes that underpins the remarkable success of plants. Evidence is mounting that hormones control many of these light‐mediated changes. Therefore, if we are to understand how light manipulates development we need to explore the interplay between light and hormonal signalling. Toward this goal, this review highlights the known convergence points of the phytochrome and the hormonal networks and explores their interactions.

Contents

Summary
449

I.
Introduction
449

II.
The phytochrome protein
450

III.
Bacteriophytochromes
450

IV.
IBacteriophytochrome signalling
450

V.
Plant phytochrome signalling
451

VI.
Ethylene perception and signalling
451

VII.
Cytokinin perception and signalling
452

VIII.
Brassinosteroid perception and signalling
453

IX.
Gibberellin signalling
455

X.
Auxin signalling
456

XI.
Proteolysis in light and hormonal signalling
458

XII.
Conclusion
459

Acknowledgements
459

References
459
Anti‐microbial hand washes for domestic use – their effectiveness in vitro and in normal use
Authors: Sharp Kay , Haysom Iain , Parkinson Rosamund 
Published: March 2003

AbstractThe killing or removal of microbes from the hands is a critical factor in food safety as many studies have shown the hands to be both an important source of microbes and powerful agents of cross‐contamination in hospital and domestic situations. In response to this concern, a number of novel hand‐washing products have appeared on the market. These products contain anti‐microbial agents and claim to be more effective at removing bacteria than soap bars and conventional liquid soaps. This study attempts to test these claims by comparing the effectiveness of a conventional soap bar, a conventional liquid soap and an anti‐microbial liquid soap containing triclosan. In vitro tests demonstrate that the anti‐microbial liquid soap is more effective than conventional liquid soaps in reducing the viability of six bacterial species and that this effect is both time and dose dependent. However, when the three soaps were compared for their ability to reduce microbial counts on the hands no differences were observed between the three products. For all three soaps, counts after washing sometimes went up and sometimes down when compared with pre‐wash counts. This was the case both when the soaps were used ‘normally’– that is, with great variation in the time taken, water and soap volumes used and method of washing and after a standardized, rigorous wash recommended in clinical situations. Furthermore, reduction in microbial counts from hands contaminated by handling raw meat was no greater for the anti‐microbial than for the conventional liquid soap.
Incommensurate paradigms? Bridging the divide between technocrats and the lay public in health care planning: recent experience from Wales
Authors: Longley Marcus 
Published: March 2003

AbstractThe pressure on the UK National Health Service (NHS) to increase public involvement in the planning of future services has never been greater. Politicians and others argue that ‘lay wisdom’ has much to contribute, and that such involvement is essential if public confidence in the service is to be maintained. Many managers and clinicians, however, operating within an essentially technocratic paradigm, remain unconvinced. Their views are often reinforced by a lack of experience of methods for public involvement that can meet the many practical difficulties involved. Using Arnstein’s ‘ladder of citizen participation’, this paper describes the principal nuances of these two paradigms, explores the nature of the conflict between them, and assesses the extent to which they are really incommensurate. It then briefly describes some of the key methodological principles emerging from public involvement work in parts of the NHS in Wales, and assesses their potential to bridge the divide between the paradigms.
Mycobacterium aviumssp.paratuberculosis: its incidence, heat resistance and detection in milk and dairy products
Authors: Grant Irene R , Rowe Michael T , Dundee Louise , Hitchings Edward 
Published: March 2003

Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne’s disease in cattle and other ruminants and has been implicated as a possible cause of Crohn’s disease in humans. The organism gains access to raw milk directly through excretion into the milk within the udder, and indirectly through faecal contamination during milking. MAP has been shown to survive commercial pasteurization in naturally infected milk, even at the extended holding time of 25 s. Pasteurized milk must therefore be considered a vehicle of transmission of MAP to humans. Isolation methods for MAP from milk are problematical, chiefly because of the absence of a suitable selective medium. This makes food surveillance programs and research on this topic difficult. The MAP problem can be addressed in two main ways: by devising a milk‐processing strategy that ensures the death of the organism; and/or strategies at farm level to prevent access of the organism into raw milk. Much of the research to date has been devoted to determining if a problem exists and, if so, the extent of the problem. Little has been directed at possible solutions. Given the current state of information on this topic and the potential consequences for the dairy industry, research is urgently needed so that a better understanding of the risks and the efficacy of possible processing solutions can be determined.
Building bridges: towards integrated library and information services for mental health and social care
Authors: Blackburn Norma 
Published: March 2003

AbstractThis research focuses on identifying the information needs of health professionals, social workers and staff from voluntary agencies, who work together in the provision of services for people with a mental illness. The aim is to provide a fully integrated library and information service for mental health and social care. A number of recent government reports have prompted this research. These have culminated in the publication of the National Service Framework for Mental Health. It was decided to conduct a qualitative study using 17 semi‐structured interviews with individuals and multi‐professional groups. A thematic analysis highlighted a number of key themes including: information need, information seeking behaviour and information flows. Results have indicated that because of the dispersed nature of mental health services, across primary and secondary care, and from statutory and non‐statutory organisations, information technology is viewed as the only realistic vehicle to provide the required information. As specialist mental health trusts are configured, covering wider geographical areas, this can only increase the reliance on information technology, for information access and information sharing.
Carbohydrate–protein interactions between HNK‐1‐reactive sulfoglucuronyl glycolipids and the proteoglycan lectin domain mediate neuronal cell adhesion and neurite outgrowth
Authors: Miura Ryu , Ethell Iryna M. , Yamaguchi Yu 
Published: March 2003

Lecticans, a family of chondroitin sulfate proteoglycans, represent the largest group of proteoglycans expressed in the nervous system. We previously showed that the C‐type lectin domains of lecticans bind two classes of sulfated cell surface glycolipids, sulfatides and HNK‐1‐reactive sulfoglucuronylglycolipids (SGGLs). In this paper, we demonstrate that the interaction between the lectin domain of brevican, a nervous system‐specific lectican, and cell surface SGGLs acts as a novel cell recognition system that promotes neuronal adhesion and neurite outgrowth. The Ig chimera of the brevican lectin domain bind to the surface of SGGL‐expressing rat hippocampal neurons. The substrate of the brevican chimera promotes adhesion and neurite outgrowth of hippocampal neurons. The authentic, full‐length brevican also promotes neuronal cell adhesion and neurite outgrowth. These activities of brevican substrates are neutralized by preincubation of cells with HNK‐1 monoclonal antibodies and by pretreatment of the brevican substrates with purified SGGLs. Brevican and HNK‐1 carbohydrates are coexpressed in specific layers of the developing hippocampus where axons from entorhinal neurons elongate. Our observations suggest that cell surface SGGLs and extracellular lecticans comprise a novel cell‐substrate recognition system operating in the developing nervous system.
Synaptotagmin I is a molecular target for lead
Authors: Bouton Christopher M. L. S. , Frelin Laurence P. , Forde Cameron E. , Godwin Hilary Arnold , Pevsner Jonathan 
Published: March 2003

Lead poisoning can cause a wide range of symptoms with particularly severe clinical effects on the CNS. Lead can increase spontaneous neurotransmitter release but decrease evoked neurotransmitter release. These effects may be caused by an interaction of lead with specific molecular targets involved in neurotransmitter release. We demonstrate here that the normally calcium‐dependent binding characteristics of the synaptic vesicle protein synaptotagmin I are altered by lead. Nanomolar concentrations of lead induce the interaction of synaptotagmin I with phospholipid liposomes. The C2A domain of synaptotagmin I is required for lead‐mediated phospholipid binding. Lead protects both recombinant and endogenous rat brain synaptotagmin I from proteolytic cleavage in a manner similar to calcium. However, lead is unable to promote the interaction of either recombinant or endogenous synaptotagmin I and syntaxin. Finally, nanomolar concentrations of lead are able to directly compete with and inhibit the ability of micromolar concentrations of calcium to induce the interaction of synaptotagmin I and syntaxin. Based on these findings, we conclude that synaptotagmin I may be an important, physiologically relevant target of lead.
Molecular cloning and characterization of hNP22: a gene up‐regulated in human alcoholic brain
Authors: Fan Li , Jaquet Vincent , Dodd Peter R. , Chen Wenbin , Wilce Peter A. 
Published: March 2003

An improved differential display technique was used to search for changes in gene expression in the superior frontal cortex of alcoholics. A cDNA fragment was retrieved and cloned. Further sequence of the cDNA was determined from 5′ RACE and screening of a human brain cDNA library. The gene was named hNP22 (human neuronal protein 22). The deduced protein sequence of hNP22 has an estimated molecular mass of 22.4 kDa with a putative calcium‐binding site, and phosphorylation sites for casein kinase II and protein kinase C. The deduced amino acid sequence of hNP22 shares homology (from 67% to 42%) with four other proteins, SM22α, calponin, myophilin and mp20. Sequence homology suggests a potential interaction of hNP22 with cytoskeletal elements. hNP22 mRNA was expressed in various brain regions but in alcoholics, greater mRNA expression occurred in the superior frontal cortex, but not in the primary motor cortex or cerebellum. The results suggest that hNP22 may have a role in alcohol‐related adaptations and may mediate regulatory signal transduction pathways in neurones.