bluuebunny/crossref_metadata_2025_split huggingface dataset:
The debate about drag and reconfiguration of freshwater macrophytes: comparing results obtained by three recently discussed approaches
Authors: STATZNER BERNHARD , LAMOUROUX NICOLAS , NIKORA VLADIMIR , SAGNES PIERRE 
Published: September 2006

Summary1. The paper by Sand‐Jensen (2003, Freshwater Biology, 48, 271–283) on drag and reconfiguration of freshwater macrophytes stimulated comments and a reply about the use of variables in assessments of the drag coefficient (Cd) or the Reynolds number (Re) of such plants. Although the physical argument in this debate starts from the same equations, it diverges into approaches that address differently the dynamic behaviour of flexible plants in the boundary layer flow (the typical condition experienced by lotic macrophytes).2. We compared three (potentially among many more) such different approaches using some preliminary experiments with Egeria densa by measuring drag (and other physical variables of interest) on (1) a single shoot exposed to varying flume flows; (2) a single shoot exposed to a constant flume flow, from which we subsequently pruned off pieces from the distal end; and (3) multiple shoots exposed to a constant flume flow after they had experienced replicated flow disturbances (causing shoot reconfiguration).3. These experiments illustrated that the three approaches can produce opposite trends in the relationship between Cd and Re and that, for a given plant and flow, the Cd values obtained by these approaches can differ by about two orders of magnitude. Thus, conventions about the use of variables are required for experiments on drag and reconfiguration of freshwater macrophytes, otherwise the field will be plagued by a multitude of incomparable results.
Predation by the tropical plant Utricularia foliosa
Authors: SANABRIA‐ARANDA LIZANDRO , GONZÁLEZ‐BERMÚDEZ ADRIANA , TORRES NÉSTOR NED , GUISANDE CÁSTOR , MANJARRÉS‐HERNÁNDEZ ANA , VALOYES‐VALOIS VANESSA , DÍAZ‐OLARTE JHON , ANDRADE‐SOSSA CAMILO , DUQUE SANTIAGO R. 
Published: September 2006

Summary1. We examined the prey captured by individual plants of the tropical carnivorous plant Utricularia foliosa, located in different areas along a creek in the Colombian Amazon and the zooplankton and macroinvertebrate communities associated with the plants. The aims were: (i) to determine whether bladders of different sizes within each plant catch different numbers of prey or exploit different size ranges and types of prey, (ii) if the quantity and composition of prey captured varies temporally and/or spatially and (iii) if the plant has evolved effective mechanisms of attracting prey.2. Utricularia foliosa captured the most abundant species of macroinvertebrates associated with the plant. Larger bladders captured more, larger and more diverse prey. However, benefits of the extra prey caught by large bladders were not offset by the greater cost of producing bladders larger than approximately 1650 μm.3. The number of prey captured was higher in those plants with more carbohydrates per bladder and with a higher ratio of antenna size/bladder length. The antennae enhance capture success by offering the prey a favourable substratum that exploits their natural locomotor and feeding behaviour. However, although carbohydrates may lure prey, carbohydrate production was not a strategy of the plant to enhance the capture of prey, because the amount of carbohydrates in the bladder was related to the abundance of periphyton.
Runt domain partner proteins enhance DNA binding and transcriptional repression in cultured Drosophila cells
Authors: Fujioka Miki , Yusibova Galina L , Sackerson Charles M. , Tillib Sergei , Mazo Alexander , Satake Masanobu , Goto Tadaatsu , Suzuki Yoshiaki 
Published: September 2006

Abstract Background: The Drosophila gene runt plays multiple roles during embryogenesis, including one as a pair‐rule class segmentation gene. The runt protein (Runt) contains an evolutionarily conserved domain (the Runt domain) that is found in several mammalian proteins including the human protein AML1, which is involved in many chromosome translocations associated with leukaemia. Specific DNA binding activity of a mammalian Runt domain is enhanced by a partner protein called PEBP2β/CBFβ. DNA binding activity of Drosophila Runt is also stimulated by this protein, suggesting the existence of a similar Runt partner protein in Drosophila. Results: We report here the cloning of two closely linked Drosophila genes, runt domain partner (rp) β1 and β2, that encode homologues of mouse PEBP2β/CBFβ. They are highly homologous to each other and to the mammalian counterpart. Either of the rpb proteins is capable of forming a complex with Runt and stimulating its DNA binding activity, but their temporal and spatial distributions are quite dissimilar, suggesting that functional specificity of Runt may be conferred by the interacting partner. Runt represses transcription dominantly when coexpressed with either partner in cultured cells, a function consistent with a direct role for Runt in regulating expression of the even‐skipped gene in Drosophila embryos. Conclusions: Drosophila Runt can interact with either of two Runt domain partners, and the resulting complex functions as an active repressor of transcription.
BMP‐4 mediates interacting signals between the neural tube and skin along the dorsal midline
Authors: Takahashi Yoshiko , Tonegawa Akane , Matsurnoto Kazuyuki , Ueno Naoto , Kuroiwa Atsushi , Noda Masaki , Nifuji Akira , Kondoh Hisato 
Published: September 2006

Abstract Background: The neural tube and its overlying tissues (skin and mesenchyme) interact along the dorsal midline during early development. This has been previously demonstrated experimentally in chicken embryos by the fact that the dorsal neural tube transplanted ectopically induced expression of Msx 2 in the adjacent tissues. It is important to identify the molecules responsible for these interactions. Results: We observed that BMP‐4, a member of the TGFβ‐family, is expressed in the dorsal neural tube in a pattern closely correlated with that of Msx 2. hi order to investigate whether BMP‐4 mediates the signal between the neural tube and the skin/ mesenchyme, BMP‐4 was ectopically administered in ovo either by implantation of the recombinant protein or transplantation of COS cells producing BMP‐4. Both manipulations resulted in ectopic induction of Msx 2 expression in the adjacent skin/mesenchyme. In addition, the activity of BMP‐4 in inducing Msx 2 was counteracted by the floor plate. Conclusion: These data suggest that BMP‐4 positively mediates the signals from the neural tube to the adjacent tissues and that this signal may be an essential step for the establishment of the dorsal midline structures.
The innate host defence against nematode parasites
Authors: DE VEER M. J. , KEMP J. M. , MEEUSEN E. N. T. 
Published: September 2006

SUMMARY Nematode parasites cause significant infections in both humans and animals. They are complex, multicellular organisms that present unique challenges for the host, in particular with respect to the recognition of their unusual surface structures by the innate defence system. The innate immune system is now recognized to be a critical component in the development of an adaptive effector response as well as a driver of vaccine‐induced immunity. This paper will give an overview of current research on the innate barriers and immune mechanisms, cells, and receptors involved in the innate host response to nematode parasites. It will also review the ‘nematode‐associated molecular patterns’ that may be specifically recognized by the host, in addition to other signals, such as nervous stimulation and tissue damage, that may alert the innate system to parasite invasion.
HIV and helminth co‐infection: is deworming necessary?
Authors: BORKOW G. , BENTWICH Z. 
Published: September 2006

SUMMARY We have previously suggested that helminth infections play a major role in the pathogenesis of HIV‐1 infection in Africa and other developing areas, due to their profound effects on the host immune system, which make those infected more susceptible to HIV‐1 infection and less able to cope with it. Chronic immune activation with a dominant Th2 profile, and anergy, are the hallmarks of chronic helminth infection, and may therefore account for most of these effects. In the present review, we summarize the studies that have addressed these issues and argue that despite some conflicting results, the cumulative immunological and epidemiological evidence is in favour of deworming as a preventive and possible therapeutic measure vis‐à‐vis HIV‐1 infection. We suggest that it should be at least tested on a wider and larger scale than has been done until now, because of its immense potential impact on the still raging AIDS epidemic in developing countries.
NK and LAK Susceptibility Varies Inversely with Target Cell MHC Class I Antigen Expression in a Rat Epithelial Tumour System
Authors: CARBONE E. , RACIOPPI L. , LA CAVA A. , PORTELLA G. , VELOTTI F. , ZAPPACOSTA S. , FONTANA S. 
Published: September 2006

Several cell clones derived from cell lines obtained from a rat thyroid carcinoma, induced by in vivo injection of the Kirsten murine sarcoma virus into the thyroid gland, and from its spontaneous lung metastases were analysed for their major histocompatability complex (MMC) class I antigen expression. The susceptibility lo natural killer (NK) cell lysis of these clones, differing in their levels of MHC class I antigen expression, was determined and found to vary inversely with the target cell MHC level, confirming numerous reports of the literature.We then tried to localize the step of the multistage natural cytotoxic process, in which class I antigens could interfere, and tested first whether lymphokine(IL‐2) activation of the killer (LAK) cells could overcome the differences in MHC class I expression of target cells. As this did not appear lo be the case, we studied the binding step by cither a cold target inhibition assay and a target binding assay and found that target cells expressing class I antigens show a lower competitive capacity for effector cells than targets not expressing such antigens, indicating that this interference may occur, at least in our system, in the binding step of the cytotoxic process.
Molecular karyotyping and aneuploidy detection in Arabidopsis thaliana using quantitative fluorescent polymerase chain reaction
Authors: Henry Isabelle M. , Dilkes Brian P. , Comai Luca 
Published: September 2006

SummaryCertain cellular processes are sensitive to changes in gene dosage. Aneuploidy is deleterious because of an imbalance of gene dosage on a chromosomal scale. Identification, classification and characterization of aneuploidy are therefore important for molecular, population and medical genetics and for a deeper understanding of the mechanisms underlying dosage sensitivity. Notwithstanding recent progress in genomic technologies, limited means are available for detecting and classifying changes in chromosome dose. The development of an inexpensive and scalable karyotyping method would allow rapid detection and characterization of both simple and complex aneuploid types. In addition to the problem of karyotyping, genomic and molecular genetic studies of aneuploids and polyploids are complicated by multiple heterozygous combinations possible at loci present in more than two copies. Quantitative scoring of allele genotypes would enable large‐scale population genetic experiments in polyploids, and permit genetic analyses on bulked populations in diploid species. Here, we demonstrate that quantitative fluorescent‐polymerase chain reaction (QF‐PCR) can be used to simultaneously genotype and karyotype aneuploid and polyploid Arabidopsis thaliana. Comparison of QF‐PCR with flow cytometric determination of nuclear DNA content indicated near perfect agreement between the methods, but complete karyotype resolution was only possible using QF‐PCR. A complex karyotype, determined by QF‐PCR, was validated by comparative genomic hybridization to microarrays. Finally, we screened the progeny of tetraploid individuals and found that more than 25% were aneuploid and that our artificially induced tetraploid strain produced fewer aneuploid individuals than a tetraploid strain isolated from nature.
The glucosyltransferase UGT72E2 is responsible for monolignol 4‐O‐glucoside production in Arabidopsis thaliana
Authors: Lanot Alexandra , Hodge Denise , Jackson Rosamond G. , George Gilu L. , Elias Luisa , Lim Eng‐Kiat , Vaistij Fabián E. , Bowles Dianna J. 
Published: September 2006

SummaryThe phenylpropanoid pathway in plants leads to the synthesis of a wide range of soluble secondary metabolites, many of which accumulate as glycosides. In Arabidopsis, a small cluster of three closely related genes, UGT72E1–E3, encode glycosyltransferases shown to glucosylate several phenylpropanoids in vitro, including monolignols, hydroxycinnamic acids and hydroxycinnamic aldehydes. The role of these genes in planta has now been investigated through genetically downregulating the expression of individual genes or silencing the entire cluster. Analysis of these transgenic Arabidopsis plants showed that the levels of coniferyl and sinapyl alcohol 4‐O‐glucosides that accumulate in light‐grown roots were significantly reduced. A 50% reduction in both glucosides was observed in plants in which UGT72E2 was downregulated, whereas silencing the three genes led to a 90% reduction, suggesting some redundancy of function within the cluster. The gene encoding UGT72E2 was constitutively overexpressed in transgenic Arabidopsis to determine whether increased glucosylation of monolignols could influence flux through the soluble phenylpropanoid pathway. Elevated expression of UGT72E2 led to increased accumulation of monolignol glucosides in root tissues and also the appearance of these glucosides in leaves. In particular, coniferyl alcohol 4‐O‐glucoside accumulated to massive amounts (10 μmol g−1 FW) in root tissues of these plants. Increased glucosylation of other phenylpropanoids also occurred in plants overexpressing this glycosyltransferase. Significantly changing the pattern of glycosides in the leaves also led to a pronounced change in accumulation of the hydroxycinnamic ester sinapoyl malate. The data demonstrate the plasticity of phenylpropanoid metabolism and the important role that glucosylation of secondary metabolites can play in cellular homeostasis.
An Arabidopsis chloroplast‐targeted Hsp101 homologue, APG6, has an essential role in chloroplast development as well as heat‐stress response
Authors: Myouga Fumiyoshi , Motohashi Reiko , Kuromori Takashi , Nagata Noriko , Shinozaki Kazuo 
Published: September 2006

SummaryAnalysis of albino or pale‐green (apg) mutants is important for identifying nuclear genes responsible for chloroplast development and pigment synthesis. We have identified 38 apg mutants by screening 11 000 Arabidopsis Ds‐tagged lines. One mutant, apg6, contains a Ds insertion in a gene encoding APG6 (ClpB3), a homologue of the heat‐shock protein Hsp101 (ClpB1). We isolated somatic revertants and identified two Ds‐tagged and one T‐DNA‐tagged mutant alleles of apg6. All three alleles gave the same pale‐green phenotype. These results suggest that APG6 is important for chloroplast development. The APG6 protein contains a transit peptide and is localized in chloroplasts. The plastids of apg6 pale‐green cells were smaller than those of the wild type, and contained undeveloped thylakoid membranes. APG6 mRNA accumulated in response to heat shock in various organs, but not in response to other abiotic stresses. Under normal conditions, APG6 is constitutively expressed in the root tips, the organ boundary region, the reproductive tissues of mature plants where plastids exist as proplastids, and slightly in the stems and leaves. In addition, constitutive overexpression of APG6 in transgenic plants inhibited chloroplast development and resulted in a mild pale‐green phenotype. The amounts of chloroplast proteins related to photosynthesis were markedly decreased in apg6 mutants. These results suggest that APG6 functions as a molecular chaperone involved in plastid differentiation mediating internal thylakoid membrane formation and conferring thermotolerance to chloroplasts during heat stress. The APG6 protein is not only involved in heat‐stress response in chloroplasts, but is also essential for chloroplast development.
Repeat ABO‐incompatible platelet transfusions leading to haemolytic transfusion reaction
Authors: Sadani D. T. , Urbaniak S. J. , Bruce M. , Tighe J. E. 
Published: September 2006

summary A 65‐year‐old woman, blood group A RhD positive, who had completed her first course of induction chemotherapy for acute myeloid leukaemia was transfused with apheresis platelets over a number of days.On three occasions she received group O RhD positive units, which had been screened and found not to contain high‐titre anti‐A,B isoagglutinins. Following the third unit, she developed a haemolytic transfusion reaction and died soon thereafter. This has led to change in policy of the supplying centre in testing for high‐titre anti‐A,B isoagglutinins. Blood group O apheresis platelets and fresh‐frozen plasma units are now labelled as high titre with a cut‐off of 1/50 as compared to the previous cut‐off of 1/100 for anti‐A,B isoagglutinins. A universal approach to testing donations for high‐titre anti‐A,B isoagglutinins, better compliance of guidelines and monitoring of patients is necessary.
Efficacy, safety and user‐friendliness of two devices for postoperative autologous shed red blood cell re‐infusion in elective orthopaedic surgery patients: a randomized pilot study
Authors: So‐Osman C. , Nelissen R. G. H. H. , Eikenboom H. C. J. , Brand A. 
Published: September 2006

summary To determine the safety, efficacy and user‐friendliness of two different postoperative autologous blood re‐infusion systems, an open, randomized, controlled study was performed.Eligible consecutive primary and revision total hip and knee replacement patients were randomized for one of the two systems or for a control group in which shed blood was not re‐infused. The nursing staff scored user‐friendliness. Patients were monitored after re‐infusion. In all three patient groups, a restrictive transfusion trigger was used.Sixty‐nine of 70 randomized patients were evaluated. Ease of use, efficacy and safety of both re‐infusion systems were comparable. There was no difference in allogeneic blood use between the groups. Thirty per cent of the patients re‐infused with autologous blood developed a mainly mild, febrile transfusion reaction. No other adverse reactions were seen. Signs of coagulopathy after re‐infusion were not found. In multivariate analysis, autologous re‐infusion was an independent factor associated with a shorter hospital stay. Both postoperative autologous blood re‐infusion systems were of equal efficacy and safety. The contribution of autologous wound blood re‐infusion to reduce allogeneic transfusions must be investigated in a larger study.
First encounters – deployment of defence‐related natural products by plants
Authors: Field Ben , Jordán Ferenc , Osbourn Anne 
Published: September 2006

SummaryPlant‐derived natural products have important functions in ecological interactions. In some cases these compounds are deployed to sites of pathogen challenge by vesicle‐mediated trafficking. Polar vesicle trafficking of natural products, proteins and other, as yet uncharacterized, cargo is emerging as a common theme in investigations of diverse disease resistance mechanisms in plants. Root‐derived natural products can have marked effects on interactions between plants and soilborne organisms, for example by serving as signals for initiation of symbioses with rhizobia and mycorrhizal fungi. They may also contribute to competitiveness of invasive plant species by inhibiting the growth of neighbouring plants (allelopathy). Very little is known about the mechanisms of release of natural products from aerial plant parts or from roots, although there are likely to be commonalities in these processes. There is increasing evidence to indicate that pathogens and symbionts can manipulate plant endomembrane systems to suppress host defence responses and facilitate accommodation within plant cells. The relationship between secretory processes and plant interactions forms the focus of this review, which brings together different aspects of the deployment of defence‐related natural products by plants.

Contents

Summary
193

I.
Introduction
194

II.
Natural product trafficking and plant disease resistance
195

III.
Allelopathy
199

VI.
Conclusions and future directions
203

Acknowledgements
204

References
204
Application of electron tomography to fungal ultrastructure studies
Authors: Hohmann‐Marriott Martin F. , Uchida Maho , Van De Meene Allison M. L. , Garret Matthew , Hjelm Brooke E. , Kokoori Shylaja , Roberson Robert W. 
Published: September 2006

SummaryAccess to structural information at the nanoscale enables fundamental insights into many complex biological systems. The development of the transmission electron microscope (TEM) has vastly increased our understanding of multiple biological systems. However, when attempting to visualize and understand the organizational and functional complexities that are typical of cells and tissues, the standard 2‐D analyses that TEM affords often fall short. In recent years, high‐resolution electron tomography methods, coupled with advances in specimen preparation and instrumentation and computational speed, have resulted in a revolution in the biological sciences. Electron tomography is analogous to medical computerized axial tomography (CAT‐scan imaging) except at a far finer scale. It utilizes the TEM to assemble multiple projections of an object which are then combined for 3‐D analyses. For biological specimens, tomography enables the highest 3‐D resolution (5 nm spatial resolution) of internal structures in relatively thick slices of material (0.2–0.4 µm) without requiring the collection and alignment of large numbers of thin serial sections. Thus accurate and revealing 3‐D reconstructions of complex cytoplasmic entities and architecture can be obtained. Electron tomography is now being applied to a variety of biological questions with great success. This review gives a brief introduction into cryopreservation and electron tomography relative to aspects of cytoplasmic organization in the hyphal tip of Aspergillus nidulans.

Contents

Summary
208

I.
Introduction
209

II.
Sample preparation for electron tomography
209

III.
Electron tomography
211

IV.
Model generation and segmentation
212

V.
Electron tomography of the hyphal apex of Aspergillus nidulans
213

VI.
Outlook
217

Acknowledgements
217

References
217
Automated binning of microsatellite alleles: problems and solutions
Authors: AMOS W. , HOFFMAN J. I. , FRODSHAM A. , ZHANG L. , BEST S. , HILL A. V. S. 
Published: September 2006

AbstractAs genotyping methods move ever closer to full automation, care must be taken to ensure that there is no equivalent rise in allele‐calling error rates. One clear source of error lies with how raw allele lengths are converted into allele classes, a process referred to as binning. Standard automated approaches usually assume collinearity between expected and measured fragment length. Unfortunately, such collinearity is often only approximate, with the consequence that alleles do not conform to a perfect 2‐, 3‐ or 4‐base‐pair periodicity. To account for these problems, we introduce a method that allows repeat units to be fractionally shorter or longer than their theoretical value. Tested on a large human data set, our algorithm performs well over a wide range of dinucleotide repeat loci. The size of the problem caused by sticking to whole numbers of bases is indicated by the fact that the effective repeat length was within 5% of the assumed length only 68.3% of the time.