bluuebunny/crossref_metadata_2025 huggingface dataset:
Nrf2 mediates cancer protection but not prolongevity induced by caloric restriction
Authors: Pearson Kevin J. , Lewis Kaitlyn N. , Price Nathan L. , Chang Joy W. , Perez Evelyn , Cascajo Maria Victoria , Tamashiro Kellie L. , Poosala Suresh , Csiszar Anna , Ungvari Zoltan , Kensler Thomas W. , Yamamoto Masayuki , Egan Josephine M. , Longo Dan L. , Ingram Donald K. , Navas Placido , de Cabo Rafael
Published: February 2008

Caloric restriction (CR) is the most potent intervention known to both protect against carcinogenesis and extend lifespan in laboratory animals. A variety of anticarcinogens and CR mimetics induce and activate the NF-E2-related factor 2 (Nrf2) pathway. Nrf2, in turn, induces a number of antioxidative and carcinogen-detoxifying enzymes. Thus, Nrf2 offers a promising target for anticarcinogenesis and antiaging interventions. We used Nrf2-disrupted (KO) mice to examine its role on the biological effects of CR. Here, we show that Nrf2 is responsible for most of the anticarcinogenic effects of CR, but is dispensable for increased insulin sensitivity and lifespan extension. Nrf2-deficient mice developed tumors more readily in response to carcinogen exposure than did WT mice, and CR was ineffective in suppressing tumors in the KO mice. However, CR extended lifespan and increased insulin sensitivity similarly in KO and WT mice. These findings identify a molecular pathway that dissociates the prolongevity and anticarcinogenic effects of CR.
Intervention for lateral /s/ using electropalatography (EPG) biofeedback and an intensive motor learning approach: a case report
Authors: McAuliffe Megan J. , Cornwell Petrea L.
Published: February 2008

Background: Visual biofeedback using electropalatography (EPG) has been beneficial in the treatment of some cases of lateral /s/ misarticulation. While EPG intervention is motorically based, studies have not commonly employed a motor learning approach to treatment. Furthermore, treatment success is measured primarily by change to EPG tongue–palate contact patterns and listener ratings conducted by speech–language therapists. Studies have not commonly measured articulatory change without the palate in‐situ using acoustic analysis and non‐professional listeners.

Aims: To determine if an intensive treatment programme including both visual biofeedback (EPG) and traditional articulation techniques within a motor learning paradigm would result in functional improvement to /s/ articulation in an 11‐year‐old girl with persistent lateral misarticulation.

Methods & Procedures: Treatment involved 12 sessions of therapist‐delivered treatment over 4 weeks followed by a 6‐week home programme. Outcomes of the treatment programme were measured primarily using naïve listener ratings and acoustic analysis of /s/ spectra.

Outcomes & Results: Improvements to both the perceptual and spectral characteristics of /s/ articulation occurred following the treatment programme.

Conclusions: The study highlighted the benefit of an intensive approach to intervention incorporating both visual biofeedback and traditional articulation approaches. The inclusion of a 6‐week structured home‐programme was beneficial and resulted in consolidation of treatment gains.
Exploring the implementation and use of outcome measurement in practice: a qualitative study
Authors: Skeat J. , Perry A.
Published: February 2008

Background: Outcome measurement is important to clinical practice — yet outcome many speech and language therapists find it difficult to apply measures in practice, and not all clinicians and services have been able to implement and/or use outcome measurement successfully. To date there has been little research to explain why implementation is often unsuccessful, and to provide clinicians and managers with direction as to the likely barriers and facilitators which should be considered.

Aims: To develop a theoretical framework to explain the implementation and use of outcome measurement in clinical practice by speech and language therapists.

Methods & Procedures: A qualitative, inductive theory‐building approach, using grounded theory methodology, was applied. This included theoretical sampling, constant comparison, memo writing, and theoretical integration. Participants were 16 Australian managers and clinicians who were using, or who had used, outcome measures.

Outcomes & Results: The resulting theoretical framework explains two interactive stages that occur when speech pathologists attempt to use outcome measurements in practice. First, clinicians must ‘try on’ outcome measurement in their own context, examining the way it fits with existing areas, such as their normal practices and priorities, and the wider group and organizational context. Having identified where outcome measurement does not ‘fit’, clinicians attempt to ‘align’ outcome measurement with the context (or vice versa), in order to create a better fit between the two. Strategies of ‘tailoring’ outcome measurement (e.g. using only parts of a measure) or ‘accommodating’ outcome measurement (e.g. changing routines to allow time for outcome measurement ratings) are possible, but are dependent on clinicians having a true picture of outcome measurement, the role and need for the data, and the existing context. Clinicians must also have control over the areas that need to change in order for outcome measurement and the context to ‘align’. Where outcome measurement and the context can be aligned, outcome measures are more easily used.

Conclusions: The theory provides a framework for considering the use of outcome measurement in clinical practice. Implications for implementing outcome measurement in clinical practice are discussed, including the need to clarify the role and need for the data; the requirement that clinicians understand how outcome measurement fits with context outside of their own personal purview; and the need for managers to support change to areas that are outside of the control of clinicians.
Patients' experiences of disruptions associated with post‐stroke dysarthria
Authors: Dickson Sylvia , Barbour Rosaline S. , Brady Marian , Clark Alexander M. , Paton Gillian
Published: February 2008

Background: Post‐stroke dysarthria rehabilitation should consider social participation for people with dysarthria, but before this approach can be adopted, an understanding of the psychosocial impact of dysarthria is required. Despite the prevalence of dysarthria as a result of stroke, there is a paucity of research into this communication disorder, particularly studies that address the experiences of individuals. The available literature focuses mainly on the perceptions of others or includes groups of mixed aetiologies.

Aims: To investigate the beliefs and experiences of people with dysarthria as a result of stroke in relation to their speech disorder, and to explore the perceived physical, personal and psychosocial impacts of living with dysarthria.

Methods & Procedures: Participants for this qualitative study were recruited from twelve hospitals in Scotland that served both rural and urban populations and afforded opportunity for comparison. Semi‐structured, in‐depth interviews were carried out over a 12‐month period with 24 individuals with varying severity of dysarthria following stroke. The interviews were orthographically transcribed and coded using the NVivo package, which also facilitated identification of patterns using the constant comparative method.

Outcomes & Results: The results of the study indicate that the effects of dysarthria following stroke extend beyond the physiological characteristics of the impairment. In turn, the resulting communication difficulties lead to changes in self‐identity, relationships, social and emotional disruptions, and feelings of stigmatization or perceived stigmatization. The impact of dysarthria was found to be disproportionate to the physiological severity, with participants continually striving to get their speech back to ‘normal’.

Conclusions & Implications: The findings provide insight into the psychosocial impact of dysarthria following stroke. Speech and language therapy interventions need to go beyond the speech impairment to address and promote psychosocial well being, reduce the likelihood of feelings of stigmatization and changes in self‐identity, irrespective of the severity of dysarthria.
Treatment history and its relationship to outcome in psychotherapy for depression
Authors: Grenyer Brin F. S. , Deane Frank P. , Lewis Kate L.
Published: February 2008

Patients with major depression can expect an average of four depressive episodes in their lifetime. Thus most clients presenting to therapy have had multiple prior episodes of treatment. These ‘psychotherapy careers’ have as yet received only minimal study and there is little data regarding the relationship of these prior treatments and responsiveness to psychotherapy. Aim: To explore prior treatment history and its relationship to psychotherapy outcome in people with major depression. Method: For 48 individuals with major depression presenting to an Australian community‐based psychotherapy facility, structured diagnostic and treatment history interviews were taken and outcomes monitored. Results: In all, 90% had received some form of prior psychotherapy or counselling with on average 3.5 previous episodes of care (range 1–7). This Australian sample was less likely to have received group, family, or couples therapy than international samples. Those receiving psychotherapy at the time of intake showed higher levels of improvement over the following 12 months, although a more chronic subsample remained symptomatic and were seeking further therapy at follow‐up. Discussion: Those actively engaged in some therapy experience at intake benefited more than those with an ‘interrupted’ psychotherapy career. Enhancing recent episodes of care may be helpful in achieving better long‐term outcomes.
Australian women who seek counselling: Psychosocial, health behaviour, and demographic profile
Authors: Schofield Margot J. , Khan Asaduzzaman
Published: February 2008

Despite high rates of psychological distress in the Australian community, particularly among middle‐aged women, use of counselling and psychological services is relatively low. This study examined self‐reported use of counselling in the previous year among a population‐based sample of 11,201 Australian women aged 50–55, and describes the profile of women who seek counselling. Using multivariate analyses to control confounding, women who had consulted a counsellor/psychologist/social worker in the previous year (6.9%) were found to have increased odds of higher stress, life satisfaction, and perceived control, and lower optimism. They also had higher odds of: experiencing more life events over the previous 12 months, changed health status compared with a year ago, taking more prescribed medications, living in urban versus rural areas, having university versus no formal education, living alone or with others rather than with a spouse/partner, and having ancillary versus full private health insurance. This multivariate profile is discussed in relation to the delivery, marketing, and accessibility of counselling services in the Australian community. The implications for counsellor training and the future development of the profession are also discussed.
Exploring theatre of the oppressed in family therapy clinical work and supervision
Authors: Proctor Kerry , Perlesz Amaryll , Moloney Banu , McIlwaine Fiona , O'Neill Imogen
Published: February 2008

Augusto Boal's theatre of the oppressed (TOTO) techniques have been used in education, health, welfare, and prison systems world‐wide. However, the link between family therapy clinical supervision and training and TOTO has not been explored, either in Australia or overseas. This innovative action research project explores the ways family therapists and supervisors apply these theatre techniques in their everyday practice. Employing a group‐based, cooperative inquiry method, 12 experienced family therapists from the Bouverie Centre, Melbourne, reflected on what these techniques have to offer family therapists and counsellors, applied these theatre techniques in their work, and contrasted TOTO with other action techniques used by family therapists. The researchers found that TOTO provided a safe and grounded process that brings ‘action’ into both therapy and supervision in ways that enable clients, families, students, and therapists to explore their own agency in a range of settings.
With feeling: Writing emotion into counselling and psychotherapy research
Authors: Lewis Ione
Published: February 2008

Counsellors and psychotherapists bring unique knowledge to the field of research about the necessity for empathic connection to access participants’ lived experience, and about the co‐construction of knowledge by participant and researcher. The current study formed part of a broader study of the professional identity of social workers as counsellors and psychotherapists and the development of their practice‐based wisdom. Specifically, this study explored social workers’ narratives about critical incidents in their practice with particular reference to analysing the emotional experience of practitioners and the emotional response of the researcher. The sample comprised 18 clinical social workers who practised as therapists. They were purposively selected from professional associations and networks. Two semi‐structured one‐hour interviews were conducted with each participant, using professional biography and critical incident interviewing techniques. Interviews were transcribed, coded, and analysed using the NVivo software program, which facilitates a grounded theory qualitative analysis. The findings presented are from analysis of two participants’ interviews, which yielded rich emotional content in relation to both participant and researcher. The study concludes that revealing the researcher's identificatory processes, resulting from participants’ narratives, leads to a more truthful and accountable description of data collection and analysis in qualitative research and highlights how the researcher co‐constructs the data during data collection and analysis. This article advocates accepting subjectivity as an inevitable aspect of research and argues for the need to write subjectivity into research reports.
Australian counsellors and psychotherapists: A profile of the profession
Authors: Schofield Margot J.
Published: February 2008

In the absence of comprehensive Australian data on the counselling and psychotherapy profession, this study aimed to examine the profile of professionals affiliated with the Psychotherapy and Counselling Federation of Australia (PACFA) to inform future policy and service planning. PACFA's first workforce survey was undertaken in 2004. This cross‐sectional survey was mailed and e‐mailed to all members of the 41 professional associations affiliated with PACFA. A total of 316 full responses were received. This paper presents findings related to demographics, training and specialisation, theoretical orientation, professional affiliations, work and practice settings, and work roles. The study provides a baseline for future workforce surveys and a resource for policy development for the profession.
Nuclear polyglutamine-containing protein aggregates as active proteolytic centers
Authors: Chen Min , Singer Lena , Scharf Andrea , von Mikecz Anna
Published: February 2008

Protein aggregates and nuclear inclusions (NIs) containing components of the ubiquitin–proteasome system (UPS), expanded polyglutamine (polyQ) proteins, and transcriptional coactivators characterize cellular responses to stress and are hallmarks of neurodegenerative diseases. The biological function of polyQ-containing aggregates is unknown. To analyze proteasomal activity within such aggregates, we present a nanoparticle (NP)-based method that enables controlled induction of sodium dodecyl sulfate–resistant inclusions of endogenous nuclear proteins while normal regulatory mechanisms remain in place. Consistent with the idea that the UPS maintains quality control, inhibition of proteasomal proteolysis promotes extra large protein aggregates (1.4–2 μm), whereas formation of NP-induced NIs is found to be inversely correlated to proteasome activation. We show that global proteasomal proteolysis increases in NP-treated nuclei and, on the local level, a subpopulation of NIs overlaps with focal domains of proteasome-dependent protein degradation. These results suggest that inclusions in the nucleus constitute active proteolysis modules that may serve to concentrate and decompose damaged, malfolded, or misplaced proteins.
Mouse TEX15 is essential for DNA double-strand break repair and chromosomal synapsis during male meiosis
Authors: Yang Fang , Eckardt Sigrid , Leu N. Adrian , McLaughlin K. John , Wang Peijing Jeremy
Published: February 2008

During meiosis, homologous chromosomes undergo synapsis and recombination. We identify TEX15 as a novel protein that is required for chromosomal synapsis and meiotic recombination. Loss of TEX15 function in mice causes early meiotic arrest in males but not in females. Specifically, TEX15-deficient spermatocytes exhibit a failure in chromosomal synapsis. In mutant spermatocytes, DNA double-strand breaks (DSBs) are formed, but localization of the recombination proteins RAD51 and DMC1 to meiotic chromosomes is severely impaired. Based on these data, we propose that TEX15 regulates the loading of DNA repair proteins onto sites of DSBs and, thus, its absence causes a failure in meiotic recombination.
Identification of ERGIC-53 as an intracellular transport receptor of α1-antitrypsin
Authors: Nyfeler Beat , Reiterer Veronika , Wendeler Markus W. , Stefan Eduard , Zhang Bin , Michnick Stephen W. , Hauri Hans-Peter
Published: February 2008

Secretory proteins are exported from the endoplasmic reticulum (ER) by bulk flow and/or receptor-mediated transport. Our understanding of this process is limited because of the low number of identified transport receptors and cognate cargo proteins. In mammalian cells, the lectin ER Golgi intermediate compartment 53-kD protein (ERGIC-53) represents the best characterized cargo receptor. It assists ER export of a subset of glycoproteins including coagulation factors V and VIII and cathepsin C and Z. Here, we report a novel screening strategy to identify protein interactions in the lumen of the secretory pathway using a yellow fluorescent protein–based protein fragment complementation assay. By screening a human liver complementary DNA library, we identify α1-antitrypsin (α1-AT) as previously unrecognized cargo of ERGIC-53 and show that cargo capture is carbohydrate- and conformation-dependent. ERGIC-53 knockdown and knockout cells display a specific secretion defect of α1-AT that is corrected by reintroducing ERGIC-53. The results reveal ERGIC-53 to be an intracellular transport receptor of α1-AT and provide direct evidence for active receptor-mediated ER export of a soluble secretory protein in higher eukaryotes.
The yeast p24 complex is required for the formation of COPI retrograde transport vesicles from the Golgi apparatus
Authors: Aguilera-Romero Auxiliadora , Kaminska Joanna , Spang Anne , Riezman Howard , Muñiz Manuel
Published: February 2008

The p24 family members are transmembrane proteins assembled into heteromeric complexes that continuously cycle between the ER and the Golgi apparatus. These cargo proteins were assumed to play a structural role in COPI budding because of their major presence in mammalian COPI vesicles. However, this putative function has not been proved conclusively so far. Furthermore, deletion of all eight yeast p24 family members does not produce severe transport phenotypes, suggesting that the p24 complex is not essential for COPI function. In this paper we provide direct evidence that the yeast p24 complex plays an active role in retrograde transport from Golgi to ER by facilitating the formation of COPI-coated vesicles. Therefore, our results demonstrate that p24 proteins are important for vesicle formation instead of simply being a passive traveler, supporting the model in which cargo together with a small GTPase of the ARF superfamily and coat subunits act as primer for vesicle formation.
The wages of CIN
Authors: Yuen Karen W. , Desai Arshad
Published: February 2008

Aneuploidy and chromosome instability (CIN) are hallmarks of the majority of solid tumors, but the relationship between them is not well understood. In this issue, Thompson and Compton (Thompson, S.L., and D.A. Compton. 2008. Examining the link between chromosomal instability and aneuploidy in human cells. J. Cell. Biol. 180:665–672) investigate the mechanism of CIN in cancer cells and find that CIN arises primarily from defective kinetochore–spindle attachments that evade detection by the spindle checkpoint and persist into anaphase. They also explore the consequences of artificially elevating chromosome missegregation in otherwise karyotypically normal cells. Their finding that induced aneuploidy is rapidly selected against suggests that the persistence of aneuploid cells in tumors requires not only chromosome missegregation but also additional, as yet poorly defined events.
The AKT–mTOR axis regulates de novo differentiation of CD4+Foxp3+ cells
Authors: Haxhinasto Sokol , Mathis Diane , Benoist Christophe
Published: February 2008

CD4+Foxp3+ regulatory T (T reg) cells play an essential role in maintaining immunological tolerance via their suppressive function on conventional CD4+ T (Tconv) cells. Repertoire studies suggest that distinct T cell receptor signaling pathways lead to T reg differentiation, but the signals that regulate T reg specification are largely unknown. We identify AKT as a strong repressor of entry into the T reg phenotype in vitro and in vivo. A constitutively active allele of AKT substantially diminished TGF-β–induced Foxp3 expression in a kinase-dependent manner and via a rapamycin-sensitive pathway, implicating the AKT–mammalian target of rapamycin axis. The observed impairment in Foxp3 induction was part of a broad dampening of the typical T reg transcriptional signature. Expression of active AKT at a stage before Foxp3 turn on during normal T reg differentiation in the thymus selectively impaired differentiation of CD4+Foxp3+ cells without any alteration in the positive selection of Tconv. Activated AKT, in contrast, did not affect established Foxp3 expression in T reg cells. These results place AKT at a nexus of signaling pathways whose proper activation has a strong and broad impact on the onset of T reg specification.
Would Caccini approve?
Authors: Bass John
Published: February 2008

Although it is known that improvisation was an important part of musical performance in the 16th and 17th centuries, studying how extemporaneous elements were incorporated into real-world situations has proven to be difficult. Improvisers, by nature, do not record what they do, but there is evidence that points to some of these individuals attempting to document their approach to music, namely in ornamentation manuals and individual pieces with written-out embellishment. Among these sources is British Library Ms. Egerton 2971, a 37-folio volume probably dating from the second or third decade of the 17th century, which contains, among other things, embellished versions of Giulio Caccini’s Amarilli, mia bella and Dolcissimo sospiro, first published in Le nuove musiche (Florence, 1602). Sources like this, despite some inherent problems, offer the clearest window into the minds of improvisers of the time, and warrant further study.

The research in this article serves two purposes. First, the versions of Amarilli, mia bella and Dolcissimo sospiro contained in Egerton 2971 will be examined and compared to those published in Le nuove musiche as a case study of early 17th-century improvisation. Second, because of Caccini’s open disdain for singers taking liberties with his compositions, an attempt will be made to see if these pieces might be examples of such treatments. The crux of the article aims to show that ornamentation of the time, at least as shown in these examples, was not a random act of substituting stereotyped musical patterns for given intervals, but instead points to a more robust idea of improvisatory thought. Rather than looking at individual ornaments or how specific musical gestures might have painted certain words, the overall structure of the ornamentation is examined to show that it is subject to deeper and subtler intellectual considerations of poetic structure, overall musical structure, and rhetoric.
Oct4 dependence of chromatin structure within the extended Nanog locus in ES cells
Authors: Levasseur Dana N. , Wang Jianlong , Dorschner Michael O. , Stamatoyannopoulos John A. , Orkin Stuart H.
Published: February 2008

Embryonic stem (ES) cells offer insight into early developmental fate decisions, and their controlled differentiation may yield vast regenerative potential. The molecular determinants supporting ES cell self-renewal are incompletely understood. The homeodomain proteins Nanog and Oct4 are essential for mouse ES cell self-renewal. Using a high-throughput approach, we discovered DNaseI hypersensitive sites and potential regulatory elements along a 160-kb region of the genome that includes GDF3, Dppa3, and Nanog. We analyzed gene expression, chromatin occupancy, and higher-order chromatin structure throughout this gene locus and found that expression of the reprogramming factor Oct4 is required to maintain its integrity.
Cep164 is a mediator protein required for the maintenance of genomic stability through modulation of MDC1, RPA, and CHK1
Authors: Sivasubramaniam Sudhakar , Sun Xuemin , Pan Yen-Ru , Wang Shaohui , Lee Eva Y.-H.P.
Published: February 2008

The activation of the ataxia telangiectasia mutated (ATM) and ATM/Rad3-related (ATR) kinases triggers a diverse cellular response including the initiation of DNA damage-induced cell cycle checkpoints. Mediator of DNA Damage Checkpoint protein, MDC1, and H2AX are chromatin remodeling factors required for the recruitment of DNA repair proteins to the DNA damage sites. We identified a novel mediator protein, Cep164 (KIAA1052), that interacts with both ATR and ATM. Cep164 is phosphorylated upon replication stress, ultraviolet radiation (UV), and ionizing radiation (IR). Ser186 of Cep164 is phosphorylated by ATR/ATM in vitro and in vivo. The phosphorylation of Ser186 is not affected by RPA knockdown but is severely hampered by MDC1 knockdown. siRNA-mediated silencing of Cep164 significantly reduces DNA damage-induced phosphorylation of RPA, H2AX, MDC1, CHK2, and CHK1, but not NBS1. Analyses of Cep164 knockdown cells demonstrate a critical role of Cep164 in G2/M checkpoint and nuclear divisions. These findings reveal that Cep164 is a key player in the DNA damage-activated signaling cascade.
Host‐specific effect of P1 exchange between two potyviruses
Authors: SALVADOR BEATRIZ , SAÉNZ PILAR , YANGÜEZ EMILIO , QUIOT JEAN BERNARD , QUIOT LAURENCE , DELGADILLO MARÍA OTILIA , GARCÍA JUAN ANTONIO , SIMÓN‐MATEO CARMEN
Published: February 2008

The potyvirusesPlum pox virus(PPV) andTobacco vein mottling virus(TVMV) have distinct host ranges and induce different symptoms in their common herbaceous hosts. To test the relevance of the P1 protein in host compatibility and pathogenicity, hybrid viruses were constructed in which the P1 coding sequence of PPV was completely or partially replaced by the corresponding sequences from TVMV. Infections induced by these chimeric viruses revealed that the TVMV P1 and a PPV/TVMV hybrid P1 proteins are functionally equivalent in herbaceous plants to the P1 protein of a PPV isolate adapted to these hosts, in spite of having high sequence divergence. Moreover, the presence of TVMV P1 sequences enhanced the competence of a low‐infectivity PPV‐D‐derived chimera inNicotiana clevelandii. Conversely, all PPV/TVMV hybrids were unable to infectPrunus persicae, a specific host for PPV, suggesting that TVMV P1 is not functionally competent in this plant. Together, these data highlight the importance of the P1 protein in defining the virus host range.
Lettuce mosaic virus: from pathogen diversity to host interactors
Authors: GERMAN‐RETANA SYLVIE , WALTER JOCELYNE , LE GALL OLIVIER
Published: February 2008

Taxonomy:  Lettuce mosaic virus (LMV) belongs to the genus Potyvirus (type species Potato virus Y) in the family Potyviridae.

Physical properties:  The virion is filamentous, flexuous with a length of 750 nm and a width of 15 nm. The particles are made of a genomic RNA of 10 080 nucleotides, covalently linked to a viral‐encoded protein (the VPg) at the 5′ end and with a 3′ poly A tail, and encapsidated in a single type of capsid protein. The molecular weight of the capsid protein subunit has been estimated electrophoretically to be 34 kDa and estimated from the amino acid sequence to be 31 kDa.

Genome organization:  The genome is expressed as a polyprotein of 3255 amino‐acid residues, processed by three virus‐specific proteinases into ten mature proteins.

Hosts:  LMV has a worldwide distribution and a relatively broad host range among several families. Weeds and ornamentals can act as local reservoirs for lettuce crops. In particular, many species within the family Asteraceae are susceptible to LMV, including cultivated and ornamental species such as common (Lactuca sativa), prickly (L. serriola) or wild (L. virosa) lettuce, endive/escarole (Cichorium endiva), safflower (Carthamus tinctorius), starthistle (Centaurea solstitialis), Cape daisy (Osteospermum spp.) and gazania (Gazania rigens). In addition, several species within the families Brassicaceae, Cucurbitaceae, Fabaceae, Solanaceae and Chenopodiaceae are natural or experimental hosts of LMV.

Genetic control of resistance to LMV:  The only resistance genes currently used to protect lettuce crops worldwide are the recessive genes mo11 and mo12 corresponding to mutant alleles of the gene encoding the translation initiation factor eIF4E in lettuce. It is believed that at least one intact copy of eIF4E must be present to ensure virus accumulation.

Transmission:  LMV is transmitted in a non‐persistent manner by a high number of aphid species. Myzus persicae and Macrosiphum euphorbiae are particularly active in disseminating this virus in the fields. LMV is also seedborne in lettuce. The effectiveness of LMV transmission depends on the cultivar and the age of the seed carrier at the inoculation time.

Symptoms:  The characteristic symptoms on susceptible lettuce cultivars are dwarfism, mosaic, distortion and yellowing of the leaves with sometimes a much reduced heart of lettuce (failure to form heads). The differences in virus strains, cultivars and the physiological stage of the host at the moment of the attack cause different symptom severity: from a very slight discoloration of the veins to severe necrosis leading to the death of the plant.
Transcriptome analysis of the wheat–Puccinia striiformis f. sp. tritici interaction
Authors: CORAM TRISTAN E. , WANG MEINAN , CHEN XIANMING
Published: February 2008

Stripe rust [caused by Puccinia striiformis Westend. f. sp. tritici Eriks. (Pst)] is a destructive disease of wheat (Triticum aestivum L.) worldwide. Genetic resistance is the preferred method for control and the Yr5 gene, originally identified in Triticum spelta var. album, represents a major resistance (R) gene that confers all‐stage resistance to all currently known races of Pst in the United States. To identify transcripts associated with the Yr5‐mediated incompatible interaction and the yr5‐compatible interaction, the Wheat GeneChip was used to profile the changes occurring in wheat isolines that differed for the presence of the Yr5 gene after inoculation with Pst. This time‐course study (6, 12, 24 and 48 h post‐inoculation) identified 115 transcripts that were induced during the R‐gene‐mediated incompatible interaction, and 73 induced during the compatible interaction. Fifty‐four transcripts were induced in both interactions and were considered as basal defence transcripts, whilst 61 transcripts were specific to the incompatible interaction [hypersensitive response (HR)‐specific transcripts] and 19 were specific to the compatible interaction (biotrophic interaction‐specific transcripts). The temporal pattern of transcript accumulation showed a peak at 24 h after infection that may reflect haustorial penetration by Pst at ~16 h. An additional 12 constitutive transcript differences were attributed to the presence of Yr5 after eliminating those considered as incomplete isogenicity. Annotation of the induced transcripts revealed that the presence of Yr5 resulted in a rapid and amplified resistance response involving signalling pathways and defence‐related transcripts known to occur during R‐gene‐mediated responses, including protein kinase signalling and the production of reactive oxygen species leading to a hypersensitive response. Basal defence also involved substantial induction of many defence‐related transcripts but the lack of R‐gene signalling resulted in weaker response.
Differential protein expression in Colletotrichum acutatum: changes associated with reactive oxygen species and nitrogen starvation implicated in pathogenicity on strawberry
Authors: BROWN SIGAL HOROWITZ , YARDEN ODED , GOLLOP NATAN , CHEN SONGBI , ZVEIBIL AIDA , BELAUSOV EDUARD , FREEMAN STANLEY
Published: February 2008

The cellular outcome of changes in nitrogen availability in the context of development and early stages of pathogenicity was studied by quantitative analysis of two‐dimensional gel electrophoresis of Colletotrichum acutatum infecting strawberry. Significant alterations occurred in the abundance of proteins synthesized during appressorium formation under nitrogen‐limiting conditions compared with a complete nutrient supply. Proteins that were up‐ or down‐regulated were involved in energy metabolism, nitrogen and amino acid metabolism, protein synthesis and degradation, response to stress and reactive oxygen scavenging. Members belonging to the reactive oxygen species (ROS) scavenger machinery, superoxide dismutase and glutathione peroxidase, were up‐regulated at the appressorium formation stage, as well as under nitrogen‐limiting conditions relative to growth with a complete nutrient supply, whereas abundance of bifunctional catalase was up‐regulated predominantly at the appressorium formation stage. Fungal ROS were detected within germinating conidia during host pre‐penetration, penetration and colonization stages, accompanied by plant ROS, which were abundant in the apoplastic space. Application of exogenous antioxidants quenched ROS production and reduced the frequency of appressorium formation. Up‐regulation in metabolic activity was detected during appressorium formation and nutrient deficiency compared with growth under complete nutrient supply. Enhanced levels of proteins related to the glyoxylate cycle and lipid metabolism (malate dehydrogenase, formate dehydrogenase and acetyl‐CoA acetyltransferase) were observed at the appressorium formation stage, in contrast to down‐regulation of isocitrate dehydrogenase. The present study demonstrates that appressoria formation processes, occurring under nutritional deprivation, are accompanied by metabolic shifts, and that ROS production is an early fungal response that may modulate initial stages of pathogen development.
Citrus tristeza virus: a pathogen that changed the course of the citrus industry
Authors: MORENO PEDRO , AMBRÓS SILVIA , ALBIACH‐MARTÍ MARIA R. , GUERRI JOSÉ , PEÑA LEANDRO
Published: February 2008

Citrus tristeza virus (CTV) (genus Closterovirus, family Closteroviridae) is the causal agent of devastating epidemics that changed the course of the citrus industry. Adapted to replicate in phloem cells of a few species within the family Rutaceae and to transmission by a few aphid species, CTV and citrus probably coevolved for centuries at the site of origin of citrus plants. CTV dispersal to other regions and its interaction with new scion varieties and rootstock combinations resulted in three distinct syndromes named tristeza, stem pitting and seedling yellows. The first, inciting decline of varieties propagated on sour orange, has forced the rebuilding of many citrus industries using tristeza‐tolerant rootstocks. The second, inducing stunting, stem pitting and low bearing of some varieties, causes economic losses in an increasing number of countries. The third is usually observed by biological indexing, but rarely in the field. CTV polar virions are composed of two capsid proteins and a single‐stranded, positive‐sense genomic RNA (gRNA) of ~20 kb, containing 12 open reading frames (ORFs) and two untranslated regions (UTRs). ORFs 1a and 1b, encoding proteins of the replicase complex, are directly translated from the gRNA, and together with the 5′ and 3′UTRs are the only regions required for RNA replication. The remaining ORFs, expressed via 3′‐coterminal subgenomic RNAs, encode proteins required for virion assembly and movement (p6, p65, p61, p27 and p25), asymmetrical accumulation of positive and negative strands during RNA replication (p23), or suppression of post‐transcriptional gene silencing (p25, p20 and p23), with the role of proteins p33, p18 and p13 as yet unknown. Analysis of genetic variation in CTV isolates revealed (1) conservation of genomes in distant geographical regions, with a limited repertoire of genotypes, (2) uneven distribution of variation along the gRNA, (3) frequent recombination events and (4) different selection pressures shaping CTV populations. Measures to control CTV damage include quarantine and budwood certification programmes, elimination of infected trees, use of tristeza‐tolerant rootstocks, or cross protection with mild isolates, depending on CTV incidence and on the virus strains and host varieties predominant in each region. Incorporating resistance genes into commercial varieties by conventional breeding is presently unfeasible, whereas incorporation of pathogen‐derived resistance by plant transformation has yielded variable results, indicating that the CTV–citrus interaction may be more specific and complex than initially thought. A deep understanding of the interactions between viral proteins and host and vector factors will be necessary to develop reliable and sound control measures.
Combined thermotherapy and cryotherapy for efficient virus eradication: relation of virus distribution, subcellular changes, cell survival and viral RNA degradation in shoot tips
Authors: WANG QIAOCHUN , CUELLAR WILMER J. , RAJAMÄKI MINNA‐LIISA , HIRATA YUKIMASA , VALKONEN JARI P. T.
Published: February 2008

Accumulation of viruses in vegetatively propagated plants causes heavy yield losses. Therefore, supply of virus‐free planting materials is pivotal to sustainable crop production. In previous studies, Raspberry bushy dwarf virus (RBDV) was difficult to eradicate from raspberry (Rubus idaeus) using the conventional means of meristem tip culture. As shown in the present study, it was probably because this pollen‐transmitted virus efficiently invades leaf primordia and all meristematic tissues except the least differentiated cells of the apical dome. Subjecting plants to thermotherapy prior to meristem tip culture heavily reduced viral RNA2, RNA3 and the coat protein in the shoot tips, but no virus‐free plants were obtained. Therefore, a novel method including thermotherapy followed by cryotherapy was developed for efficient virus eradication. Heat treatment caused subcellular alterations such as enlargement of vacuoles in the more developed, virus‐infected cells, which were largely eliminated following subsequent cryotherapy. Using this protocol, 20–36% of the treated shoot tips survived, 30–40% regenerated and up to 35% of the regenerated plants were virus‐free, as tested by ELISA and reverse transcription loop‐mediated isothermal amplification. Novel cellular and molecular insights into RBDV–host interactions and the factors influencing virus eradication were obtained, including invasion of shoot tips and meristematic tissues by RBDV, enhanced viral RNA degradation and increased sensitivity to freezing caused by thermotherapy, and subcellular changes and subsequent death of cells caused by cryotherapy. This novel procedure should be helpful with many virus–host combinations in which virus eradication by conventional means has proven difficult.
Role of a xyloglucan‐specific endo‐β‐1,4‐glucanase inhibitor in the interactions ofNicotiana benthamianawithColletotrichum destructivum,C. orbiculareorPseudomonas syringaepv.tabaci
Authors: XIE W. , HAO L. , GOODWIN P. H.
Published: February 2008

A xyloglucan‐specific endo‐β‐1,4‐glucanase inhibitor cDNA,NbXEGIP1, was amplified from diseased leaves ofNicotiana benthamiana. The sequence was similar to the tomato xyloglucan‐specific endo‐β‐1,4‐glucanase inhibitor (XEGIP) and tobacco nectarin IV genes that have been described as binding and inactivating fungal Family 12 xyloglucan‐specific endo‐β‐1,4‐glucanases. Expression ofNbXEGIP1was not detected in healthy leaves, but the gene was induced during the later stages of infection by the fungiColletotrichum destructivumandC. orbiculare. Induction ofNbXEGIP1also occurred during disease development by the bacteriumPseudomonas syringaepv.tabaciand during the hypersensitive response produced byP. syringaepv.tabaciexpressingavrPto. A portion ofNbXEGIP1was cloned into a tobacco rattle virus vector for virus‐induced gene silencing inN. benthamiana. SilencingNbXEGIP1did not affect the interactions with eitherColletotrichumspecies but did significantly reduce population levels ofP. syringaepv.tabaciin the compatible interaction andP. syringaepv.tabaciexpressingavrPtoin the incompatible interaction. In the susceptible response toP. syringaepv.tabaci, silencing ofNbXEGIP1also resulted in visibly wilted leaves several hours prior to necrosis, which was not observed in control plants. This was related to a significantly higher level of electrolyte leakage and higher expression of a defensin gene from infectedNbXEGIP1‐silenced leaves compared with control leaves. Silencing appeared to be specific as it did not affect expression of a related gene,NbXEGIP2.NbXEGIP1may act as an inhibitor of a bacterial enzyme that degrades the xyloglucan–cellulose plant cell‐wall network, and degradation of the cell wall results in host membrane disruption and signalling of defence responses.
Involvement of ZFR1 of Fusarium verticillioides in kernel colonization and the regulation of FST1, a putative sugar transporter gene required for fumonisin biosynthesis on maize kernels
Authors: BLUHM B. H. , KIM H. , BUTCHKO R. A. E. , WOLOSHUK C. P.
Published: February 2008

Fumonisins comprise a class of carcinogenic mycotoxins produced by Fusarium verticillioides during colonization of maize kernels. In previous work, we identified ZFR1, which is predicted to encode a Zn(II)2Cys6 zinc finger transcription factor required for fumonisin B1 (FB1) production during growth on kernels. In this study, we characterized the role of ZFR1 in colonizing maize kernels and inducing FB1 biosynthesis. The ZFR1 deletion strain (Δzfr1) grew approximately 2.5‐fold less than the wild‐type on endosperm tissue and a variety of other carbon sources, including glucose and amylopectin. However, the Δzfr1 strain displayed higher α‐amylase activity and expression of genes involved in starch saccharification than the wild‐type, thus indicating that the reduced growth of the Δzfr1 strain was not due to inhibition of amylolytic enzymes. In the wild‐type strain, expression of six genes encoding putative sugar transporters was significantly greater on endosperm tissue than on germ tissue, and expression of at least three of the six genes was negatively affected by disruption of ZFR1. Intriguingly, disruption of FST1 had no effect on growth, kernel colonization or kernel pH but decreased FB1 production by approximately 82% on maize kernels. Based on these findings, we hypothesize that ZFR1 controls FB1 biosynthesis by regulating genes involved in the perception or uptake of carbohydrates.
Adult plant resistance‐related gene expression in ‘Camp Remy’ wheat inoculated withPuccinia striiformis
Authors: MALLARD STÉPHANIE , NÈGRE SYLVIE , POUYA SHALA , GAUDET DENIS , LU ZHEN‐XIANG , DEDRYVER FRANÇOISE
Published: February 2008

The French wheat variety ‘Camp Remy’ (CR) possesses a durable, adult plant resistance to yellow rust (YR), caused by the pathogenPuccinia striiformis. Using cDNA–AFLP on different sets of heterogeneous inbred families (HIFs) derived from the cross CR × Récital, we compared gene expression profiles during one seedling and two adult developmental stages following inoculation withP. striiformis. Transcripts differentially expressed in response to YR infection were isolated and cloned. Sequence analysis of the resultant clones revealed several classes of putative genes, including those related to resistance/defence responses, transcription and signal transduction, and primary metabolism. The expression profiles of seven selected genes were obtained using real‐time PCR in CR leaves at the same three stages of development. The results confirmed the stage‐specific expression of the genes at one or two specific stages in response toP. striiformisinfection and demonstrated that CR modifies the expression of some resistance/defence‐related genes during its transition from the seedling to adult growth stages. These results provided the first clue to understand the molecular basis of quantitative trait loci for adult plant resistance to YR and connect it with durability.
Contact person as a court‐ordered solution in child visitation disputes in Sweden
Authors: Andersson Gunvor , Arvidsson Maria Bangura
Published: February 2008

Separated parents have the joint responsibility to give their children access to the other parent. If they fail to reach a visitation agreement, the District Court will decide on one for them. In Sweden one demand can be supervision by a contact person. This paper is about court‐ordered visitations including supervision by a contact person. Different public systems, with different interpretations of the best interest of the child, have to interact in these cases: the District Court makes the decision on supervised visitation and the Social Services appoint a contact person and follow the intervention up. There is a shortage of research on this use of a contact person, and an exploratory research project is carried through: Three small‐scale studies, based on group‐interviews with family law social workers, social files and individual interviews with contact persons, supplement each other and form together a Social Services perspective on the intervention. The results are presented according to five themes: Social Services and the court; the families and children concerned; contact arrangements; termination of the intervention; Social Services' perceptions of the intervention. The conclusion is that contact person is perceived as a positive solution for children in visitation disputes involving risk. However, the intervention brings up some contradictory interests important to be conscious of.