bluuebunny/crossref_metadata_2025 huggingface dataset:
The Cellular Basis for Enhanced Volume-modulated Cardiac Output in Fish Hearts
Authors: Shiels Holly A. , Calaghan Sarah C. , White Ed
Published: June 2006

During vertebrate evolution there has been a shift in the way in which the heart varies cardiac output (the product of heart rate and stroke volume). While mammals, birds, and amphibians increase cardiac output through large increases in heart rate and only modest increases (∼30%) in stroke volume, fish and some reptiles use modest increases in heart rate and very large increases in stroke volume (up to 300%). The cellular mechanisms underlying these fundamentally different approaches to cardiac output modulation are unknown. We hypothesized that the divergence between volume modulation and frequency modulation lies in the response of different vertebrate myocardium to stretch. We tested this by progressively stretching individual cardiac myocytes from the fish heart while measuring sarcomere length (SL), developed tension, and intracellular Ca2+ ([Ca2+]i) transients. We show that in fish cardiac myocytes, active tension increases at SLs greater than those previously demonstrated for intact mammalian myocytes, representing a twofold increase in the functional ascending limb of the length–tension relationship. The mechanism of action is a length-dependent increase in myofilament Ca2+ sensitivity, rather than changes in the [Ca2+]i transient or actin filament length in the fish cell. The capacity for greater sarcomere extension in fish myocardium may be linked to the low resting tension that is developed during stretch. These adaptations allow the fish heart to volume modulate and thus underpin the fundamental difference between the way fish and higher vertebrates vary cardiac output.
Playing Games with African Lives: The G7 Debt Relief Strategy and the Politics of Indifference
Authors: Cheru Fantu
Published: June 2006

This chapter examines the politics of policy reform in low-income Africa, and specifically the double standard applied by the creditor countries in dealing with the debts of middle-income Latin American and low-income African countries. Whereas the Latin American debt was promptly dealt with by Western creditors because of the risk it posed to the stability of the Western banking system, equal attention was never given to the debt burden of the poorest African countries, whose debts were largely owed to multilateral financial institutions. Finally, the chapter examines the adequacy of the heavily indebted poor countries (HIPC) initiative, which was introduced in 1996 to address the problem of debt owed by low-income countries to the multilateral development banks.
Ecological Debt—The Economic Possibilities for Our Grandchildren
Authors: Simms Andrew
Published: June 2006

This chapter broadens the analysis of sovereign debt by incorporating ecological concerns. Centuries of consumption of the natural resources of the developing world by the developed world, resources that in many cases were acquired illegally or by force, have produced what is describes as an ecological debt of the rich countries to the poor countries. The imbalance in resource consumption helps explain the dramatic divergence in income levels between rich nations and poor nations that has occurred since the early 20th century. It is argued that there is a sustainable equilibrium in the use of the world's natural resources — clean air, fresh water, timber, and petroleum. The wealthy nations of the world have upset that equilibrium at the expense of the poor — taking more than their share of the goods while inflicting the costs of resource depletion and pollution on the poor.
Using International Finance to Further Conservation: The First 15 Years of Debt-for-Nature Swaps
Authors: Reilly William K.
Published: June 2006

This chapter examines debt-for-nature swaps and their potential for offsetting sovereign debt. Debt-for-nature swaps originated in the 1980s as a way of preserving natural areas in the developing world while at the same time reducing the external debt of the host country. The win-win nature of this type of transaction created many potential applications, and the US Congress and other national legislatures soon passed legislation enabling billions of dollars worth of swaps to take place. However, that potential was never realized. Legislative mandates were not funded, developing countries became suspicious of swaps as they believed they posed a threat to their sovereignty, and an improvement in debt markets reduced the attractiveness of swap economics. It is argued that although swaps are not a panacea for either debt reduction or environmental protection, they offer a concrete tool to promote both ends, and tremendous potential for swaps still exists.
Dealing with Sovereign Debt: Trends and Implications
Authors: Porzecanski Arturo C.
Published: June 2006

This chapter provides an overview of the reasons behind sovereign debt defaults. It discusses trends in external indebtedness (public and private) and in government indebtedness (domestic and foreign). It describes the manner in which private lenders and investors, and official bilateral and multilateral agencies, have dealt with sovereign defaults during the 1980s and 1990s. It closes with an in-depth consideration of the case of Argentina post-2001, which promises to be the most complex sovereign default case in contemporary history. It argues that private lenders and investors have been, and continue to be, able to deal promptly and effectively with instances of sovereign default, such that new, supranational bankruptcy procedures are not necessary.
Darwin and Pangenesis
Authors: Stanford P. Kyle
Published: June 2006

This chapter focuses on the history of our theorizing about the phenomena of generation and inheritance. It attempts to show that according to historical records, our efforts to theorize about inheritance and generation continued to be plagued by the problem of unconceived alternatives long after we came to embrace substantive evidential, metaphysical, and methodological constraints essentially continuous with those of the present day. It is argued that Darwin shows no evidence of having considered and rejected the idea that similarities between ancestors and offspring might be results of a common cause rather than links in a causal chain, and indeed shows no evidence of even having been able to understand this line of thought when it was explicitly presented to him directly by Galton. Instead the most natural conclusion to draw from the historical evidence is that Darwin simply failed to conceive of or consider the entire class of theoretical alternatives to pangenesis picked out by this idea, notwithstanding the fact that it offered an equally promising strategy for explaining what he took to be the central phenomena of inheritance and generation.
SeqVis: Visualization of compositional heterogeneity in large alignments of nucleotides
Authors: Ho Joshua W. K. , Adams Cameron E. , Lew Jie Bin , Matthews Timothy J. , Ng Chiu Chin , Shahabi-Sirjani Arash , Tan Leng Hong , Zhao Yu , Easteal Simon , Wilson Susan R , Jermiin Lars S
Published: June 2006

Summary: Most phylogenetic methods assume that the sequences evolved under homogeneous, stationary and reversible conditions. Compositional heterogeneity in data intended for studies of phylogeny suggests that the data did not evolve under these conditions. SeqVis, a Java application for analysis of nucleotide content, reads sequence alignments in several formats and plots the nucleotide content in a tetrahedron. Once plotted, outliers can be identified, thus allowing for decisions on the applicability of the data for phylogenetic analysis.

Availability:  

Contact:  lars.jermiin@usyd.edu.au
‘The Song Unsung’: Luigi Nono's Il canto sospeso
Authors: Nielinger Carola
Published: June 2006

Taking into account the sources now available at the Archivio Luigi Nono in Venice, this article first looks at Nono's serial masterpiece Il canto sospeso (1955–6) in its historical context, both in Germany and in Italy. Having outlined the political circumstances and aesthetic premisses, the article goes on to provide a detailed analysis of the serial technique employed. Particular attention is paid to a technique of pitch permutation that explains the pitch structures of several movements, hitherto not fully understood. Each of the nine movements is examined in view of a better understanding of the work's expressive qualities and in order to show the underlying formal and compositional relationships.
Adorno's Mahler and the Timbral Outsider
Authors: Sheinbaum John J.
Published: June 2006

Orchestral colour can be read as an important part, both literally and metaphorically, of Theodor W. Adorno's approach to Mahler. Adorno's examples of ‘breakthrough’, ‘suspension’ and ‘fulfilment’ show that timbre, traditionally considered largely irrelevant to music's deep structure, plays a significant role in his conception of Mahlerian form. For Adorno, these musical relationships resonated strongly with his post-Second World War concern for the plight of the outsider within the homogenizing bounds of modern society.
An ontology of scientific experiments
Authors: Soldatova Larisa N , King Ross D
Published: June 2006

The formal description of experiments for efficient analysis, annotation and sharing of results is a fundamental part of the practice of science. Ontologies are required to achieve this objective. A few subject-specific ontologies of experiments currently exist. However, despite the unity of scientific experimentation, no general ontology of experiments exists. We propose the ontology EXPO to meet this need. EXPO links the SUMO (the Suggested Upper Merged Ontology) with subject-specific ontologies of experiments by formalizing the generic concepts of experimental design, methodology and results representation. EXPO is expressed in the W3C standard ontology language OWL-DL. We demonstrate the utility of EXPO and its ability to describe different experimental domains, by applying it to two experiments: one in high-energy physics and the other in phylogenetics. The use of EXPO made the goals and structure of these experiments more explicit, revealed ambiguities, and highlighted an unexpected similarity. We conclude that, EXPO is of general value in describing experiments and a step towards the formalization of science.
Modelling dynamics of the type I interferon response toin vitroviral infection
Authors: Howat Tom J , Barreca Cristina , O'Hare Peter , Gog Julia R , Grenfell Bryan T
Published: June 2006

Innate immunity is crucial in the early stages of resistance to novel viral infection. The family of cytokines known as the interferons (IFNs) forms an essential component of this system: they are responsible for signalling that an infection is underway and for promoting an antiviral response in susceptible cells. We construct a spatial stochastic model, parameterized by experimental data and informed by analytic approximation, to capture the dynamics of virus–IFN interaction duringin vitroinfection of Madin–Darby bovine kidney cell monolayers by Herpes simplex virus 1. The dose dependence of infection progression, subsequent monolayer destruction and IFN-β production are investigated. Implications forin vivoinfections, in particular the priming of susceptible cells by IFN-β during infection, are considered.
Frequency of recovery of pathogens causing acute maxillary sinusitis in adults before and after introduction of vaccination of children with the 7-valent pneumococcal vaccine
Authors: Brook Itzhak , Foote Perry A. , Hausfeld Jeffrey N.
Published: June 2006

The objective of the study was to compare the proportions of the recovery of pathogens of acute maxillary sinusitis in adults in the 4-year period prior to the 5-year period that followed the introduction of vaccination of children with the 7-valent pneumococcal vaccine (PCV7). Cultures were obtained through endoscopy from 385 adults with acute maxillary sinusitis, 156 between 1997 and 2000, and 229 between 2001 and 2005. One hundred and seventeen potentially pathogenic organisms were isolated from the cultures obtained between 1997 and 2000. The predominant organisms were Streptococcus pneumoniae (54 or 46 % of all isolates), Haemophilus influenzae non-type b (42 or 36 %), Moraxella catarrhalis (7 or 6 %), Streptococcus pyogenes (8 or 7 %) and Staphylococcus aureus (6 or 5 %). One hundred and sixty-seven potentially pathogenic organisms were isolated from the cultures obtained between 2001 and 2005. The most predominant organisms were H. influenzae non-type b (71 or 43 % of all isolates), Strep. pneumoniae (58 or 35 %), M. catarrhalis (13 or 8 %), Strep. pyogenes (12 or 7 %) and Staph. aureus (13 or 8 %). Significant statistical differences were noted in the rates of recovery of H. influenzae non-type b (P<0.05) and Strep. pneumoniae (P<0.05). A decrease occurred in the recovery of Strep. pneumoniae resistant to penicillin from 41 to 29 %, and an increase was noted in the isolation of beta-lactamase-producing H. influenzae from 33 to 39 %; however, neither change was statistically significant. These data illustrate that a significant shift occurred in the causative pathogens of acute maxillary sinusitis in adults in the 5 years after the introduction of vaccination of children with the PCV7 compared to the previous 4 years.
Chlamydia pneumoniae infection of microglial cells in vitro: a model of microbial infection for neurological disease
Authors: Ikejima Hideaki , Friedman Herman , Yamamoto Yoshimasa
Published: June 2006

Chlamydia pneumoniae is the aetiological cause of a wide variety of chronic inflammatory diseases and may be associated with neurological disease. Microbiological and immunological aspects of the interaction between C. pneumoniae and the central nervous system (CNS) are not well understood because of the lack of a suitable infection model for neuronal studies. In the present study, an in vitro C. pneumoniae infection model was developed in the established microglial cell line EOC 20. Infection of the cells resulted in obvious induction of proinflammatory cytokines. The infection also selectively induced matrix metalloproteinase-9 (MMP-9) but not MMP-2. Moreover, beta interferon, which is known to modulate CNS disease, inhibited induction of MMP-9 following C. pneumoniae infection. These results support the view that C. pneumoniae infection may be associated with marked alteration of the ability of microglial cells to enhance cytokine production as well as induction of an MMP.
Microscopic, cultural and molecular evidence of disseminated invasive aspergillosis involving the lungs and the gastrointestinal tract
Authors: Jayshree R. S. , Shafiulla M. , George J. , David J. K. , Bapsy P. P. , Chakrabarti A.
Published: June 2006

A patient with acute promyelocytic leukaemia developed invasive aspergillosis post chemotherapy during a pancytopenic episode, clinically involving the lungs and the gastrointestinal tract. Dichotomously branched septate fungal hyphae were demonstrated microscopically in stools and sputa. Cultures of the samples yielded Aspergillus flavus, which were identical by RFLP and random amplification of polymorphic DNA analyses and antifungal MICs, proving disseminated disease. To the best of the author's knowledge, this is the first time that boluses of fungal hyphae have been demonstrated microscopically in the stools of a patient with gastrointestinal aspergillosis.
Effect of N-chlorotaurine on Aspergillus, with particular reference to destruction of secreted gliotoxin
Authors: Reeves Emer P. , Nagl Markus , O'Keeffe Joseph , Kelly Judy , Kavanagh Kevin
Published: June 2006

The fungistatic and fungicidal activity ofN-chlorotaurine (NCT), a long-lived oxidant produced by stimulated neutrophils, was investigated. Physiological concentrations (75–100 μM) of NCT showed clear fungicidal activity against a range ofAspergillusisolates. Moreover, killing by NCT was significantly increased in the presence of ammonium chloride, explained by the formation of monochloramine by halogenation of ammonium. One clinical isolate ofAspergillus fumigatuswas characterized for the production of the immunosuppressive agent gliotoxin, and NCT was shown to cause destruction of gliotoxin, possibly via reduction of the disulphide bridge. Because of its endogenous nature and its high antifungal activity, NCT appears to be a good choice for topical treatment ofAspergillusinfections, and the results of this study further substantiate its therapeutic efficacy.
Molecular characterization of antimicrobial resistance in Shigella sonnei isolates in Korea
Authors: Seol Sung Yong , Kim Yong Tae , Jeong Young Sook , Oh Jae Young , Kang Hee Young , Moon Dong Chan , Kim Jungmin , Lee Yoo Chul , Cho Dong Taek , Lee Je Chul
Published: June 2006

The antimicrobial resistance of 122 Shigella sonnei isolates obtained in Korea during the period 1991–2000 was characterized. These isolates were highly resistant to traditional antibiotics such as trimethoprim (100 %), streptomycin (100 %), sulfamethoxazole (94 %), tetracycline (93 %) and nalidixic acid (90 %). All S. sonnei isolates carried Tn7 in their chromosomes. The 8.4 kb non-transferable resistance (R) plasmid carrying tetA, strA-strB and sul1 was found in 93 % of the S. sonnei isolates. Resistance to nalidixic acid first appeared in a S. sonnei isolate in 1997, and then in all S. sonnei isolates from 1998 and 1999. Resistance to commonly prescribed antibiotics such as ampicillin was increased in S. sonnei isolates during the outbreak period 1998–2000. Resistance to ampicillin was mediated by the conjugative R plasmids carrying bla
TEM-1. In conclusion, S. sonnei acquired antimicrobial resistance to commonly prescribed antibiotics through the horizontal transfer of conjugative R plasmids, while the genetic stability of transposon and non-transferable R plasmids was responsible for resistance to traditional antibiotics.
Influence of colostrum deprivation and concurrent Cryptosporidium parvum infection on the colonization and persistence of Escherichia coli O157 : H7 in young lambs
Authors: Ragione R. M. La , Best A. , Clifford D. , Weyer U. , Johnson L. , Marshall R. N. , Marshall J. , Cooley W. A. , Farrelly S. , Pearson G. R. , Woodward M. J.
Published: June 2006

Escherichia coliO157 : H7 andCryptosporidium parvuminfections of man have been associated with direct contact with small ruminants. Colostrum protects neonates against gastrointestinal pathogens, and orphan lambs, which are common on petting farms, may be deprived of this protection. In a recent study, it was demonstrated that high shedding ofE. coliO157 : H7 by an 8-week-old goat kid was associated with coincidentalC. parvuminfection. Furthermore, both pathogens were co-located in the distal gastrointestinal tract. It was hypothesized that colostrum deprivation and pre-infection withC. parvumpredisposed young ruminants to colonization and increased shedding ofE. coliO157 : H7. To test this, 21 lambs 5 weeks of age were divided into four groups as follows: (A) colostrum-deprived and inoculated withE. coliO157 : H7, (B) colostrum-deprived and inoculated withC. parvumand thenE. coliO157 : H7, (C) conventionally reared and inoculated withE. coliO157 : H7, (D) conventionally reared and inoculated withC. parvumand thenE. coliO157 : H7.C. parvumwas detected between 8 and 12 days post-inoculation in most of the infected lambs. At 24 h post-inoculation withE. coliO157 : H7, all lambs were shedding between 5×104and 5×107 c.f.u.E. coliO157 : H7 per gram of faeces.E. coliO157 : H7 was shed in higher numbers in the groups pre-inoculated withC. parvum, whether conventionally reared or colostrum-deprived. Interestingly, for the colostrum-deprived lambs on day 3, a significant difference in shedding ofE. coliO157 : H7 was observed (P=0.038), with the lambs inoculated withE. colialone yielding higher counts than those pre-inoculated withC. parvum. From day 15 onwards, shedding ofE. coliO157 : H7 was highest from the colostrum-deprivedC. parvum-infected lambs, then (in descending order of shedding) the colostrum-deprived lambs, the conventionally reared lambs infected withC. parvum, and the conventionally reared animals. In total, four animals were euthanized, two at 24 h and two at 96 h post inoculation withE. coliO157 : H7 (two conventionally reared and two colostrum-deprived). All animals euthanized were from groups pre-inoculated withC. parvumprior to challenge withE. coliO157 : H7. On examination of tissues, in three of the four animals examined, multifocal attaching and effacing lesions were observed in the caecum, colon, rectum and at the recto-anal junction, and were confirmed by immunohistochemistry to be associated withE. coliO157 : H7.
Clinical relevance of virulence genes in Campylobacter jejuni isolates in Bahrain
Authors: Al-Mahmeed Ali , Senok Abiola C. , Ismaeel Abdulrahman Y. , Bindayna Khalid M. , Tabbara Khaled S. , Botta Giuseppe A.
Published: June 2006

There are no data describing the genetic make-up of Campylobacter strains (an important aetiological agent of diarrhoea) circulating in the Arabian Gulf region. Here, the molecular characterization of two virulence genes in Campylobacter jejuni from Bahrain and the relationship with clinical infection are reported. Molecular screening for cytolethal distending toxin (cdtB) and invasion-associated marker (iam) genes was carried out on C. jejuni stool isolates collected from January 2002 to January 2004 in Bahrain. The molecular characterization was correlated with the patients' socio-demographic and clinical parameters. Of the 96 C. jejuni strains tested, 50 (52 %) were cdtB
+/iam
+, 30 (31 %) were cdtB
+/iam
− and 16 (17 %) were cdtB
−/iam
−. Sixty-nine per cent (66/96) of patients were less than 3 years old, with significantly higher detection of cdtB
+/iam
+ and cdtB
+/iam
− strains (P <0.001 and P <0.01, respectively) in this age group. Seventy patients (73 %) were symptomatic. In the group that were less than 3 years old, 62 and 85 % of those with cdtB
+/iam
+ and cdtB
+/iam
− strains, respectively, were symptomatic compared with 100 % for those over 3 years of age. However, the presence of cdtB
−/iam
− strains still resulted in clinical infection in the children under 3 years but not in the older patients. This is the first report describing the molecular characterization of virulence genes in Campylobacter isolates from this region. The findings indicate that strains of different virulence genetic make-up are circulating in the population, with children under the age of 3 years being most vulnerable. Further work on the molecular characterization, gene expression and determination of the invasive phenotypes of C. jejuni strains circulating in different regions is needed.
Streptococcus gallinaceus bacteraemia in an abattoir worker presenting with a febrile illness
Authors: Balm Michelle N. D. , Truong Han T. , Choudhary Anwar S. , Robinson Geoffrey M. , Blackmore Timothy K.
Published: June 2006

Streptococcus gallinaceusis a newly described species of viridans streptococci, previously only identified as causing disease in broiler chickens. This organism was recovered in pure culture from blood taken from a New Zealand abattoir worker presenting with a febrile illness. This first report of bacteraemia caused byS. gallinaceusin a human may help the understanding of the ecology of this recently described organism.
Invasive fungal infections: a review of epidemiology and management options
Authors: Enoch D. A. , Ludlam H. A. , Brown N. M.
Published: June 2006

Fungi are increasingly recognised as major pathogens in critically ill patients. Candida spp. and Cryptococcus spp. are the yeasts most frequently isolated in clinical practice. The most frequent filamentous fungi (moulds) isolated are Aspergillus spp., but Fusarium spp., Scedosporium spp., Penicillium spp., and Zygomycetes are increasingly seen. Several reasons have been proposed for the increase in invasive fungal infections, including the use of antineoplastic and immunosuppressive agents, broad-spectrum antibiotics, and prosthetic devices and grafts, and more aggressive surgery. Patients with burns, neutropenia, HIV infection and pancreatitis are also predisposed to fungal infection. The epidemiology and clinical features of fungal infections are reviewed, together with antifungal agents currently or soon to be available.
Visceral leishmaniasis/human immunodeficiency virus co-infection in India: the focus of two epidemics
Authors: Mathur Purva , Samantaray J. C. , Vajpayee Madhu , Samanta Palash
Published: June 2006

India contributes heavily to the global burden of visceral leishmaniasis (VL, kala-azar) and human immunodeficiency virus (HIV)/AIDS. The prevalence of HIV seropositivity in VL patients at a tertiary care centre in northern India, as observed during a prospective study over a period of 2 years, is presented. Of the 104 cases of VL/post-kala-azar dermal leishmaniasis, six (5.7 %) were found to be HIV positive, compared to 11 (5.5 %) seropositive for HIV of 198 patients with fever due to other causes. Four of the six (67 %) VL/HIV co-infected patients had a chronic/relapsing course, not responding to antileishmanial treatment. A CD4 T-cell count of <200 mm−3 was found in four of the five (80 %) co-infected patients in whom the test was done. Although the level of HIV/VL co-infection in the present study was lower than that of Mediterranean countries, there is a trend towards rising co-infection. The VL-endemic states of India have a huge population of migrant labourers, who work in high-HIV-prevalence states. The reported increase in the prevalence of HIV in the VL-endemic, populous states of India is a cause of grave concern, and co-infection may assume epidemic proportions in the coming decade if left unchecked.
Helicobacter pylori-associated oxidant monochloramine induces reactivation of Epstein–Barr virus (EBV) in gastric epithelial cells latently infected with EBV
Authors: Minoura-Etoh Junko , Gotoh Kazuyo , Sato Ryugo , Ogata Masao , Kaku Naomi , Fujioka Toshio , Nishizono Akira
Published: June 2006

To investigate the possibility of an interaction between two ubiquitous human pathogens, Helicobacter pylori and Epstein–Barr virus (EBV), the effect of monochloramine (NH2Cl), locally produced by H. pylori infection, on gastric epithelium latently infected with EBV was examined, by assessing the induction of EBV lytic infection. AGS cells harbouring latently infected EBV were used as the indicator of lytic change caused by NH2Cl treatment. Lytic infection, determined by morphological change and EA-D antigen expression, occurred immediately after treatment with in vitro-synthesized NH2Cl. Analysis of EBV infection in human gastric tissue revealed that out of 48 H. pylori-positive patients, 24 were positive for EBER-1, and 18 and 13 were positive for EBNA1 and LMP-1 antigen, respectively. The results suggest that H. pylori-associated NH2Cl induces EBV lytic conversion in gastric epithelium latently infected with EBV.
Genomic localization of RNA binding proteins reveals links between pre-mRNA processing and transcription
Authors: Swinburne Ian A. , Meyer Clifford A. , Liu X. Shirley , Silver Pamela A. , Brodsky Alexander S.
Published: June 2006

Pre-mRNA processing often occurs in coordination with transcription thereby coupling these two key regulatory events. As such, many proteins involved in mRNA processing associate with the transcriptional machinery and are in proximity to DNA. This proximity allows for the mapping of the genomic associations of RNA binding proteins by chromatin immunoprecipitation (ChIP) as a way of determining their sites of action on the encoded mRNA. Here, we used ChIP combined with high-density microarrays to localize on the human genome three functionally distinct RNA binding proteins: the splicing factor polypyrimidine tract binding protein (PTBP1/hnRNP I), the mRNA export factor THO complex subunit 4 (ALY/THOC4), and the 3′ end cleavage stimulation factor 64 kDa (CSTF2). We observed interactions at promoters, internal exons, and 3′ ends of active genes. PTBP1 had biases toward promoters and often coincided with RNA polymerase II (RNA Pol II). The 3′ processing factor, CSTF2, had biases toward 3′ ends but was also observed at promoters. The mRNA processing and export factor, ALY, mapped to some exons but predominantly localized to introns and did not coincide with RNA Pol II. Because the RNA binding proteins did not consistently coincide with RNA Pol II, the data support a processing mechanism driven by reorganization of transcription complexes as opposed to a scanning mechanism. In sum, we present the mapping in mammalian cells of RNA binding proteins across a portion of the genome that provides insight into the transcriptional assembly of RNA–protein complexes.
Pathways of Glucose Regulation of Monosaccharide Transport in Grape Cells
Authors: Conde Carlos , Agasse Alice , Glissant David , Tavares Rui , Gerós Hernâni , Delrot Serge
Published: June 2006

Grape (Vitis vinifera) heterotrophic suspension-cultured cells were used as a model system to study glucose (Glc) transport and its regulation. Cells transported d-[14C]Glc according to simple Michaelis-Menten kinetics superimposed on first-order kinetics. The saturating component is a high-affinity, broad-specificity H+-dependent transport system (Km = 0.05 mm). Glc concentration in the medium tightly regulated the transcription of VvHT1 (Vitis vinifera hexose transporter 1), a monosaccharide transporter previously characterized in grape berry, as well as VvHT1 protein amount and monosaccharide transport activity. All the remaining putative monosaccharide transporters identified so far in grape were poorly expressed and responded weakly to Glc. VvHT1 transcription was strongly repressed by Glc and 2-deoxy-d-Glc, but not by 3-O-methyl-d-Glc or Glc plus mannoheptulose, indicating the involvement of a hexokinase-dependent repression. 3-O-Methyl-d-Glc, which cannot be phosphorylated, and Glc plus mannoheptulose induced a decrease of transport activity caused by the reduction of VvHT1 protein in the plasma membrane without affecting VvHT1 transcript levels. This demonstrates hexokinase-independent posttranscriptional regulation. High Glc down-regulated VvHT1 transcription and Glc uptake, whereas low Glc increased those parameters. Present data provide an example showing control of plant sugar transporters by their own substrate both at transcriptional and posttranscriptional levels. VvHT1 protein has an important role in the massive import of monosaccharides into mesocarp cells of young grape berries because it was localized in plasma membranes of the early developing fruit. Protein amount decreased abruptly throughout fruit development as sugar content increases, consistent with the regulating role of Glc on VvHT1 expression found in suspension-cultured cells.
Pathway of Sugar Transport in Germinating Wheat Seeds
Authors: Aoki Naohiro , Scofield Graham N. , Wang Xin-Ding , Offler Christina E. , Patrick John W. , Furbank Robert T.
Published: June 2006

Three homeologous genes encoding a sucrose (Suc) transporter (SUT) in hexaploid wheat (Triticum aestivum), TaSUT1A, 1B, and 1D, were expressed in germinating seeds, where their function is unknown. All three TaSUT1 proteins were confirmed to be capable of transporting both Suc and maltose by complementation tests with the SUSY7/ura3 yeast (Saccharomyces cerevisiae) mutant strain. The role of Suc transporters in germinating grain was examined by combining in situ hybridization, immunolocalization, fluorescent dye tracer movement, and metabolite assays. TaSUT1 transcript and SUT protein were detected in cells of the aleurone layer, scutellar epidermis, scutellar ground cells, and sieve element-companion cell complexes located in the scutellum, shoot, and root. Ester loading of the membrane-impermeable fluorescent dye carboxyfluorescein into the scutellum epidermal cells of germinating seeds showed that a symplasmic pathway connects the scutellum to the shoot and root via the phloem. However, the scutellar epidermis provides an apoplasmic barrier to solute movement from endosperm tissue. Measurements of sugars in the root, shoot, endosperm, and scutellum suggest that, following degradation of endosperm starch, the resulting hexoses are converted to Suc in the scutellum. Suc was found to be the major sugar present in the endosperm early in germination, whereas maltose and glucose predominate during the later stage. It is proposed that loading the scutellar phloem in germinating wheat seeds can proceed by symplasmic and apoplasmic pathways, the latter facilitated by SUT activity. In addition, SUTs may function to transport Suc into the scutellum from the endosperm early in germination and later transport maltose.
Analysis of theArabidopsis rsr4-1/pdx1-3Mutant Reveals the Critical Function of the PDX1 Protein Family in Metabolism, Development, and Vitamin B6 Biosynthesis
Authors: Wagner Susan , Bernhardt Anne , Leuendorf Jan Erik , Drewke Christel , Lytovchenko Anna , Mujahed Nader , Gurgui Cristian , Frommer Wolf B. , Leistner Eckhard , Fernie Alisdair R. , Hellmann Hanjo
Published: June 2006

Vitamin B6 represents a highly important group of compounds ubiquitous in all living organisms. It has been demonstrated to alleviate oxidative stress and in its phosphorylated form participates as a cofactor in >100 biochemical reactions. By means of a genetic approach, we have identified a novel mutant, rsr4-1 (for reduced sugar response), with aberrant root and leaf growth that requires supplementation of vitamin B6 for normal development. Cloning of the mutated gene revealed that rsr4-1 carries a point mutation in a member of the PDX1/SOR1/SNZ (for Pyridoxine biosynthesis protein 1/Singlet oxygen resistant 1/Snooze) family that leads to reduced vitamin B6 content. Consequently, metabolism is broadly altered, mainly affecting amino acid, raffinose, and shikimate contents and trichloroacetic acid cycle constituents. Yeast two-hybrid and pull-down analyses showed that Arabidopsis thaliana PDX1 proteins can form oligomers. Interestingly, the mutant form of PDX1 has severely reduced capability to oligomerize, potentially suggesting that oligomerization is important for function. In summary, our results demonstrate the critical function of the PDX1 protein family for metabolism, whole-plant development, and vitamin B6 biosynthesis in higher plants.
JekyllEncodes a Novel Protein Involved in the Sexual Reproduction of Barley
Authors: Radchuk Volodymyr , Borisjuk Ljudmilla , Radchuk Ruslana , Steinbiss Hans-Henning , Rolletschek Hardy , Broeders Sylvia , Wobus Ulrich
Published: June 2006

Cereal seed development depends on the intimate interaction of filial and maternal tissues, ensuring nourishment of the new generation. The gene jekyll, which was identified in barley (Hordeum vulgare), is preferentially expressed in the nurse tissues. JEKYLL shares partial similarity with the scorpion Cn4 toxin and is toxic when ectopically expressed in Escherichia coli and tobacco (Nicotiana tabacum). In barley, jekyll is upregulated in cells destined for autolysis. The gene generates a gradient of expression in the nucellar projection, which mediates the maternal–filial interaction during seed filling. Downregulation of jekyll by the RNA interference technique in barley decelerates autolysis and cell differentiation within the nurse tissues. Flower development and seed filling are thereby extended, and the nucellar projection no longer functions as the main transport route for assimilates. A slowing down in the proliferation of endosperm nuclei and a severely impaired ability to accumulate starch in the endosperm leads to the formation of irregular and small-sized seeds at maturity. Overall, JEKYLL plays a decisive role in the differentiation of the nucellar projection and drives the programmed cell death necessary for its proper function. We further suggest that cell autolysis during the differentiation of the nucellar projection allows the optimal provision of basic nutrients for biosynthesis in endosperm and embryo.
Downregulation of ClpR2 Leads to Reduced Accumulation of the ClpPRS Protease Complex and Defects in Chloroplast Biogenesis inArabidopsis
Authors: Rudella Andrea , Friso Giulia , Alonso Jose M. , Ecker Joseph R. , van Wijk Klaas J.
Published: June 2006

Plastids contain tetradecameric Clp protease core complexes, with five ClpP Ser-type proteases, four nonproteolytic ClpR, and two associated ClpS proteins. Accumulation of total ClpPRS complex decreased twofold to threefold in an Arabidopsis thaliana T-DNA insertion mutant in CLPR2 designated clpr2-1. Differential stable isotope labeling of the ClpPRS complex with iTRAQ revealed a fivefold reduction in assembled ClpR2 accumulation and twofold to fivefold reductions in the other subunits. A ClpR2:(his)6 fusion protein that incorporated into the chloroplast ClpPRS complex fully complemented clpr2-1. The reduced accumulation of the ClpPRS protease complex led to a pale-green phenotype with delayed shoot development, smaller chloroplasts, decreased thylakoid accumulation, and increased plastoglobule accumulation. Stromal ClpC1 and 2 were both recruited to the thylakoid surface in clpr2-1. The thylakoid membrane of clpr2-1 showed increased carotenoid content, partial inactivation of photosystem II, and upregulated thylakoid proteases and stromal chaperones, suggesting an imbalance in chloroplast protein homeostasis and a well-coordinated network of proteolysis and chaperone activities. Interestingly, a subpopulation of PsaF and several light-harvesting complex II proteins accumulated in the thylakoid with unprocessed chloroplast transit peptides. We conclude that ClpR2 cannot be functionally replaced by other ClpP/R homologues and that the ClpPRS complex is central to chloroplast biogenesis, thylakoid protein homeostasis, and plant development.
Why Do People Engage in Collective Action? Revisiting the Role of Perceived Effectiveness
Authors: Hornsey Matthew J. , Blackwood Leda , Louis Winnifred , Fielding Kelly , Mavor Ken , Morton Thomas , O'Brien Anne , Paasonen Karl‐Erik , Smith Joanne , White Katherine M.
Published: June 2006

Research has shown limited support for the notion that perceived effectiveness of collective action is a predictor of intentions to engage in collective action. One reason may be that effectiveness has been in terms of whether the action will influence key decision makers. We argue that the effectiveness of collective action might be judged by other criteria, such as whether it influences third parties, builds an oppositional movement, and expresses values. Two hundred and thirty one attendees at a rally rated the effectiveness of the rally and their intentions to engage in future collective action. For those participants who were not members of an organization, intentions were linked to the perceived effectiveness of the rally in expressing values and influencing the public. For those who were members of an organization, intentions were linked only to the effectiveness of the rally in building an oppositional movement.
Progress Takes Work: Effects of the Locomotion Dimension on Job Involvement, Effort Investment, and Task Performance in Organizations1
Authors: Pierro Antonio , Kruglanski Arie W. , Higgins E. Tory
Published: June 2006

This research examined the relation between individual differences in the tendency toward locomotion, which is defined as a proclivity toward psychological movement; and job involvement, effort commitment, and performance in organizational contexts. Four separate studies found support for the notion that locomotion is related positively to effort investment in work activities. Locomotion also was related positively to job involvement and successful performance, as assessed by a self‐report measure and by manager ratings. Finally, the positive relation between locomotion and effort was mediated partially by job involvement, and the positive relation between locomotion and performance was mediated by effort investment. These findings are discussed in reference to the varied implications of the locomotion dimension for human functioning in organizations.
The Dynamic Interaction of Personal Norms and Environment‐Friendly Buying Behavior: A Panel Study1
Authors: Thøgersen John , Ölander Folke
Published: June 2006

A deeper understanding of the attitude–norm–behavior relationship in the environmental field can be obtained by analyzing the dynamic interaction over time between relevant attitudinal variables and specific behaviors of interest. This article is based on a panel survey with a random sample of about 1,500 Danes interviewed up to 3 times in 1998 to 2000, regarding their purchase of organic food products. The panel analysis reveals that the stronger are consumers' personal norms about buying organic food products and the less they perceive organic products as expensive, the greater the likelihood that they change their purchase patterns in favor of organic products. Furthermore, one can observe significant cross‐lagged paths from past behavior to belief and norm variables.
Affiliation Tendencies on the Eve of the Iraqi War: A Utility Theory Perspective
Authors: Rofé Yacov
Published: June 2006

Affiliation tendencies among 212 Israeli children and their parents were examined in January to March 2003, when the prospect for an Iraqi attack against Israel was high. Based on utility theory (Rofé, 1984), it was hypothesized that Israeli citizens would prefer the company of less anxious others, rather than those with similar and higher levels of anxiety. Additionally, it was expected that subjects would be less inclined to talk about war‐related issues since their need for cognitive clarity was already satisfied by the mass media. This study also compared the affiliation and discussion tendencies of children and adults. Results were consistent with utility theory and demonstrated its theoretical value in accounting for affiliation tendencies in stressful situations.
Direct‐Supervision and Remote‐Supervision Jails: A Comparative Study of Psychosocial Factors1
Authors: Yocum Rich , Anderson Jon , Davigo Teresa , Lee Shawn
Published: June 2006

The direct‐supervision style correctional facility has been offered as a design that provides a better atmosphere for staff and inmates. Prior research has shown minor support in favor of the general environment created by direct‐supervision facilities. However, the claims of benefits associated with direct supervision far outweigh the number of empirical research studies on the design. This research examined corrections officers' and inmates' feelings of boredom, perceived control, aggression, attitudes toward each other, and stress in a direct‐supervision style facility and a remote‐supervision style facility. Results from 164 inmates and 82 correctional officers showed that staff in the direct‐supervision facility reported elevated levels of perceived control, less anger and hostility, and less boredom.
Impact of Interpersonal Conflict on Individuals High in Unmitigated Communion1
Authors: Reynolds Kerry A. , Helgeson Vicki S. , Seltman Howard , Janicki Denise , Page‐Gould Elizabeth , Wardle Margaret
Published: June 2006

The current study examined the impact of interpersonal conflict on mood and physical symptoms for individuals who scored high on a personality characteristic called unmitigated communion (UC), as compared to individuals who did not score high in UC. UC is defined as a focus on others to the exclusion of the self. Forty‐one undergraduate students participated in 7 consecutive nightly interviews. Participants described their social interactions, indicated whether the interaction involved interpersonal conflict, and indicated their distress and physical symptoms at the end of the day. Multilevel modeling analysis demonstrated that conflict adversely affected UC and non‐UC individuals similarly on the same day, but had a more negative impact for UC individuals on the following day.
Adaptation of humoral memory
Authors: Höfer Thomas , Muehlinghaus Gwendolin , Moser Katrin , Yoshida Taketoshi , E. Mei Henrik , Hebel Katrin , Hauser Anja , Hoyer Bimba , O. Luger Elke , Dörner Thomas , Manz Rudolf A. , Hiepe Falk , Radbruch Andreas
Published: June 2006

Summary:  Immunological memory, as provided by antibodies, depends on the continued presence of antibody‐secreting cells, such as long‐lived plasma cells of the bone marrow. Survival niches for these memory plasma cells are limited in number. In an established immune system, acquisition of new plasma cells, generated in response to recent pathogenic challenges, requires elimination of old memory plasma cells. Here, we review the adaptation of plasma cell memory to new pathogens. This adaptation is dependent upon the influx of plasmablasts, generated in a secondary systemic immune reaction, into the pool of memory plasma cells, the efficiency of competition of new plasmablasts with old plasma cells, and the frequency of infection with novel pathogens. To maintain old plasma cells at frequencies high enough to provide protection and to accommodate as many specificities as possible, an optimal influx rate per infection exists. This optimal rate is approximately three times higher than the minimal number of plasma cells providing protection. Influx rates of plasmablasts generated by vaccination approximately match this optimum level. Furthermore, the observed stability of serum concentrations of vaccine‐specific antibodies implies that the influxing plasmablasts mobilize a similar number of plasma cells and that competitive infectious challenges are not more frequent than once per month.
Not all CD4+ memory T cells are long lived
Authors: Robertson Jennifer M. , MacLeod Megan , Marsden Vanessa S. , Kappler John W. , Marrack Philippa
Published: June 2006

Summary:  Memory T cells are thought to have several properties that distinguish them from their naïve precursors. They are found in parts of the body that rarely house naïve cells, they respond to antigen with faster proliferation and more rapid progression to effector function, they are less sensitive to the absence of their selecting major histocompatibility complex (MHC), and, above all, they are long lived. Here we show that this last property may not be universal. Some CD4+ T cells that have surface proteins characteristic of memory cells have the same half‐life in vivo as naïve cells. The description of these cells as memory cells therefore depends on our definition of the word ‘memory’.
Programming, demarcating, and manipulating CD8+ T‐cell memory
Authors: Badovinac Vladimir P. , Harty John T.
Published: June 2006

Summary:  In response to infection, antigen‐specific CD8+ T cells undergo massive expansion in numbers, acquire effector mechanisms, and disseminate throughout the body. The expansion phase is followed by a contraction (death) phase, where 90–95% of antigen‐specific CD8+ T cells are eliminated. The remaining antigen‐specific CD8+ T cells form the initial memory pool, which can be stably maintained for life. In this review, we discuss evidence that early events after infection ‘program’ CD8+ T cells to expand, contract, and generate memory in a fashion that is largely insensitive to the duration of infection or antigen display. Recent data demonstrate, despite numerical stability, that memory CD8+ T‐cell populations undergo phenotypic and functional changes with time after immunization. However, the early suggestion that specific markers can be used to identify memory CD8+ T cells has not been supported by recent studies. Thus, we argue that specific functional characteristics, such as the ability to persist and undergo vigorous secondary expansion leading to elevated memory cell numbers, remain the best markers of ‘good’ memory cells. Finally, we discuss experimental approaches to manipulate and accelerate generation of CD8+ T cells with memory characteristics, and how these systems can inform both basic and applied immunology.