bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Arabidopsis IRX9/IRX9-L and IRX14/IRX14-L Pairs of Glycosyltransferase Genes Reveals Critical Contributions to Biosynthesis of the Hemicellulose Glucuronoxylan
Authors: Wu Ai-Min , Hörnblad Emma , Voxeur Aline , Gerber Lorenz , Rihouey Christophe , Lerouge Patrice , Marchant Alan
Published: April 2010

The hemicellulose glucuronoxylan (GX) is a major component of plant secondary cell walls. However, our understanding of GX synthesis remains limited. Here, we identify and analyze two new genes from Arabidopsis (Arabidopsis thaliana), IRREGULAR XYLEM9-LIKE (IRX9-L) and IRX14-LIKE (IRX14-L) that encode glycosyltransferase family 43 members proposed to function during xylan backbone elongation. We place IRX9-L and IRX14-L in a genetic framework with six previously described glycosyltransferase genes (IRX9, IRX10, IRX10-L, IRX14, FRAGILE FIBER8 [FRA8], and FRA8 HOMOLOG [F8H]) and investigate their function in GX synthesis. Double-mutant analysis identifies IRX9-L and IRX14-L as functional homologs of IRX9 and IRX14, respectively. Characterization of irx9 irx10 irx14 fra8 and irx9-L irx10-L irx14-L f8h quadruple mutants allows definition of a set of genes comprising IRX9, IRX10, IRX14, and FRA8 that perform the main role in GX synthesis during vegetative development. The IRX9-L, IRX10-L, IRX14-L, and F8H genes are able to partially substitute for their respective homologs and normally perform a minor function. The irx14 irx14-L double mutant virtually lacks xylan, whereas irx9 irx9-L and fra8 f8h double mutants form lowered amounts of GX displaying a greatly reduced degree of backbone polymerization. Our findings reveal two distinct sets of four genes each differentially contributing to GX biosynthesis.
Five Arabidopsis Reticulon Isoforms Share Endoplasmic Reticulum Location, Topology, and Membrane-Shaping Properties
Authors: Sparkes Imogen , Tolley Nicholas , Aller Isabel , Svozil Julia , Osterrieder Anne , Botchway Stanley , Mueller Christopher , Frigerio Lorenzo , Hawes Chris
Published: April 2010

The cortical endoplasmic reticulum (ER) in tobacco (Nicotiana tabacum) epidermal cells is a network of tubules and cisternae undergoing dramatic rearrangements. Reticulons are integral membrane proteins involved in shaping ER tubules. Here, we characterized the localization, topology, effect, and interactions of five Arabidopsis thaliana reticulons (RTNs), isoforms 1-4 and 13, in the cortical ER. Our results indicate that RTNLB13 and RTNLB1-4 colocate to and constrict the tubular ER membrane. All five RTNs preferentially accumulate on ER tubules and are excluded from ER cisternae. All isoforms share the same transmembrane topology, with N and C termini facing the cytosol and four transmembrane domains. We show by Förster resonance energy transfer and fluorescence lifetime imaging microscopy that several RTNs have the capacity to interact with themselves and each other, and we suggest that oligomerization is responsible for their residence in the ER membrane. We also show that a complete reticulon homology domain is required for both RTN residence in high-curvature ER membranes and ER tubule constriction, yet it is not necessary for homotypic interactions.
Drug‐related behaviors independently associated with syphilis infection among female sex workers in two Mexico–US border cities
Authors: Loza Oralia , Patterson Thomas L. , Rusch Melanie , Martínez Gustavo A. , Lozada Remedios , Staines‐Orozco Hugo , Magis‐Rodríguez Carlos , Strathdee Steffanie A.
Published: April 2010

Aims  To identify correlates of active syphilis infection among female sex workers (FSWs) in Tijuana and Ciudad Juarez.

Design  Cross‐sectional analyses of baseline interview data. Correlates of active syphilis (antibody titers >1 : 8) were identified by logistic regression.

Setting  Tijuana and Ciudad Juarez, two Mexican cities on the US border that are situated on major drug trafficking routes and where prostitution is quasi‐legal.

Participants  A total of 914 FSWs aged ≥18 years without known human immunodeficiency virus (HIV) infection who had had recent unprotected sex with clients.

Measurements  Baseline interviews and testing for syphilis antibody using Treponema pallidum particle agglutination (TPPA) and rapid plasma reagin (RPR) tests.

Findings  Median age and duration in sex work were 32 and 4 years, respectively. Overall, 18.0% had ever injected drugs, 14.2% often or always used illegal drugs before or during sex in the past month, 31.4% had clients in the last 6 months who injected drugs, and 68.6% reported having clients from the United States. Prevalence of HIV and active syphilis were 5.9% and 10.3%, respectively. Factors independently associated with active syphilis included injecting drugs (AOR: 2.39; 95% CI: 1.40, 4.08), using illegal drugs before or during sex (AOR: 2.06; 95% CI: 1.16, 3.65) and having any US clients (AOR: 2.85; 95% CI: 1.43, 5.70).

Conclusions  Among female sex workers in Tijuana and Ciudad Juarez, drug‐using behaviors were associated more closely with active syphilis than were sexual behaviors, suggesting the possibility of parenteral transmission of T. pallidum. Syphilis eradication programs should consider distributing sterile syringes to drug injectors and assisting FSWs with safer‐sex negotiation in the context of drug use.
Comparison of transcript profiles in late blight‐challenged Solanum cajamarquense and B3C1 potato clones
Authors: LINDQVIST‐KREUZE HANNELE , CARBAJULCA DORIS , GONZALEZ‐ESCOBEDO GEOFFREY , PÉREZ WILLMER , BONIERBALE MERIDETH
Published: April 2010

Two Solanum genotypes, a wild relative of cultivated potato S. cajamarquense (Cjm) and an advanced tetraploid clone B3C1 (B3), were inoculated with two Phytophthora infestans isolates and leaves were sampled at 72 and 96 h after inoculation. Gene expression in the inoculated versus noninoculated samples was monitored using the Institute of Genomic Research (TIGR) 10K potato array and real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR). The current experiment is study number 83 of the TIGR expression profiling service project, and all data are publicly available in the Solanaceae Gene Expression Database (SGED) at ftp://ftp.tigr.org/pub/data/s_tuberosum/SGED. Differentially regulated cDNA clones were selected separately for each isolate–time point interaction by significant analysis of microarray (SAM), and differentially regulated clones were classified into functional categories by MapMan. The results show that the genes activated in B3 and Cjm have largely the same biological functions and are commonly activated when plants respond to pathogen attack. The genes activated within biological function categories were considerably different between the genotypes studied, suggesting that the defence pathways activated in B3 and Cjm during the tested conditions may involve unique genes. However, as indicated by real‐time RT‐PCR, some of the genes thought to be genotype specific may be activated across genotypes at other time points during disease development.
Cutting to cope – a modern adolescent phenomenon
Authors: Hall B. , Place M.
Published: April 2010

Background  The frequency of young people cutting themselves appears to be increasing, with one review estimating the current prevalence across the UK to be between 1 in 12 and 1 in 15.

Aim  To identify factors that are associated with self‐harm by cutting, and more especially coping strategies that if encouraged might reduce such behaviour.

Method  Multivariate and exploratory factor analysis were used to analyse the results from a survey of the pupils attending four large comprehensive schools in the North of England where the frequency of cutting behaviour was causing concern.

Results  Three factors were identified from the analysis – Social & Active Coping, Seeking External Solutions and Non‐Productive Coping. The Social & Active Coping was the only factor that significantly correlated with non‐cutting behaviour.

Conclusions  The fostering of the elements that make up Social & Active Coping – namely working successfully and feeling a sense of achievement, together with positive friendship networks and positive diversions, including physical recreation, will help to minimize young people's sense of needing to cope by cutting themselves.
Clinical applicability of T-cell interferon-α release assay for tumour necrosis factor-α inhibitor therapy in severe psoriasis
Authors: Chiang Y. Z. , Panting K. , Dever B. , Parslew R. A. G.
Published: April 2010

Many studies have found that screening and treatment of latent tuberculosis (TB) before starting treatment with tumour necrosis factor (TNF)-α inhibitors reduces associated TB infections. The new T-cell interferon-α release assay (TIGRA), is more specific and sensitive for detection of latent TB compared with the tuberculin skin test (TST). We report results of TIGRA in our first 63 patients commencing TNF-α inhibitors for severe psoriasis. Of the 63 patients, 5 (7.9%) had a positive TIGRA result and were started on treatment for latent TB. We found that the only risk factor for TB associated with a positive TIGRA was a history of travel to countries with high TB incidence. To our knowledge, this is the first study to identify the background risk (7.9%) of latent TB in an endemic UK population. This result emphasizes the importance of TIGRA testing to reduce the risk of TB in patients treated with TNF-α inhibitor.
Identifying refugia from climate change
Authors: Ashcroft Michael B.
Published: April 2010

This article highlights how the loose definition of the term ‘refugia’ has led to discrepancies in methods used to assess the vulnerability of species to the current trend of rising global temperatures. The term ‘refugia’ is commonly used without distinguishing between macrorefugia and microrefugia, ex situ refugia and in situ refugia, glacial and interglacial refugia or refugia based on habitat stability and refugia based on climatic stability. It is not always clear which definition is being used, and this makes it difficult to assess the appropriateness of the methods employed. For example, it is crucial to develop accurate fine‐scale climate grids when identifying microrefugia, but coarse‐scale macroclimate might be adequate for determining macrorefugia. Similarly, identifying in situ refugia might be more appropriate for species with poor dispersal ability but this may overestimate the extinction risk for good dispersers. More care needs to be taken to properly define the context when referring to refugia from climate change so that the validity of methods and the conservation significance of refugia can be assessed.
Little shrimp left on the shelf: the roles that sea‐level change, ocean currents and continental shelf width play in the genetic connectivity of a seagrass‐associated species
Authors: Haig Jodie A. , Connolly Rod M. , Hughes Jane M.
Published: April 2010

Aim  Caridean shrimp are diverse and abundant inhabitants of seagrass beds. Anthropogenic disturbances have already reduced and fragmented seagrass habitat, and the rate of change is likely to increase in the future. It is therefore becoming increasingly important to build a basis of understanding of connectivity among populations of seagrass‐associated fauna. Phycomenes zostericola is closely associated with seagrass and makes an ideal study species with which to explore patterns of connectivity and the influence of biogeographic boundaries and historical sea‐level changes on seagrass‐associated species. We hypothesized that strong currents and the high potential of P. zostericola for dispersal and adult movement would result, for the most part, in panmixia. We also hypothesized that if structure was evident, it would occur close to known biogeographic boundaries in Queensland.

Location  Phycomenes zostericola is an abundant shrimp species distributed throughout Queensland’s seagrass habitats. Nineteen seagrass sites from the Torres Strait Islands and Queensland coastlines were sampled.

Methods  Molecular sequence data for a 590 base pair fragment of the mitochondrial gene cytochrome c oxidase subunit I (COI) was analysed for 279 specimens of P. zostericola. Phylogeographic patterns were analysed using nested clade phylogeographic analysis (NCPA); an isolation‐by‐distance effect was tested using a Mantel test; the effect of biogeographic boundaries was tested using an analysis of molecular variance (AMOVA), and also a spatial analysis of molecular variance (SAMOVA); demographic expansions were tested for using Tajima’s D, Fu’s FS and timing estimated using mismatch analysis; the timing of vicariant events was estimated using coalescent analysis (im program).

Results  Contrary to our original hypothesis, the strong marine currents are not a connective influence among populations of P. zostericola. Regional genetic structure and an isolation‐by‐distance effect are enhanced by existing coastal biogeographic boundaries. Population genetic structure and demographic history are intricately linked to the effects of a tumultuous Pleistocene sea‐level history on the Queensland continental shelf.

Main conclusions  Connectivity diminishes among populations of P. zostericola over scales larger than a few hundred kilometres. As seagrass habitats world‐wide become increasingly fragmented, low levels of connectivity will result in an isolated future for P. zostericola and other species reliant on seagrass as habitat.
Multiple periglacial refugia in the Patagonian steppe and post‐glacial colonization of the Andes: the phylogeography of Calceolaria polyrhiza
Authors: Cosacov Andrea , Sérsic Alicia N. , Sosa Victoria , Johnson Leigh A. , Cocucci Andrea A.
Published: April 2010

Aim  We perform a phylogeographical study of an endemic Patagonian herbaceous plant to assess whether geographical patterns of genetic variation correspond to in situ Pleistocene survival or to glacial retreat and post‐glacial expansion. We also seek to determine the locations of potential glacial refugia and post‐glacial colonization routes.

Location  Southern Andes and Patagonian steppe.

Methods  We used Calceolaria polyrhiza, a widely distributed Patagonian herbaceous plant that occurs mainly in the understorey of Nothofagus rain forests and in the arid Patagonian steppe, as our model system. The chloroplast intergenic spacer trnH–psbA was sequenced for 590 individuals from 68 populations. Sequence data were analysed using phylogenetic (maximum parsimony, maximum likelihood and Bayesian inference) and population genetic (spatial analyses of molecular variance, mismatch distributions and neutrality tests) methods. Nested clade phylogeographic analyses, and divergence time estimates using a calibrated molecular clock, were also conducted.

Results  A total of 27 haplotypes identified in the present study clustered into four primary genealogical lineages, revealing three significant latitudinal phylogeographical breaks. The two high Andean lineages probably split first, during the late Miocene, and the Patagonian lineage split around 4 Ma, coincident with the establishment of the Patagonian steppe. Within each haplogroup, major diversification occurred in the Pleistocene. The Patagonian groups show a pattern consistent with a rapid post‐glacial expansion and colonization of the Andean flanks, achieved independently by four lineages. The highest haplotype diversity was found along a longitudinal transect that is remarkably congruent with the limit of the ice‐sheet extension during the Greatest Patagonian Glaciation. A north‐east expansion is evident, which is probably associated with the ‘Arid Diagonal’ fluctuations.

Main conclusions  Glacial climate fluctuations had a substantial impact on the diversification, distribution and demography of the study species. A scenario of multiple periglacial Pleistocene refugia and subsequent multiple recolonization routes, from eastern Patagonia to the Andean flanks, may explain the phylogeographical patterns observed. However, current genetic structure also preserves the imprints of older events that probably occurred in the Miocene and Pliocene, providing evidence that multiple processes, operating at different spatial and temporal scales, have moulded biodiversity in Patagonia.
Gender differences in the effect of fish oil on appetite, inflammation and nutritional status in haemodialysis patients
Authors: Zabel R. , Ash S. , King N. , Naslund E. , Bauer J.
Published: April 2010

Background:  Haemodialysis patients show signs of chronic inflammation and reduced appetite, which is associated with a worse clinical status and an increased mortality risk. Fish oil has anti‐inflammatory properties and may be useful as a therapeutic treatment. There is limited evidence to indicate the feasibility and efficacy of this intervention in dialysis patients. The present study aimed to compare the effect of 12 weeks of supplementation with fish oil on markers of appetite and inflammation in male and female haemodialysis patients.

Methods:  The study was conducted in 28 haemodialysis patients. All patients were prescribed 3 g of fish oil per day for 12 weeks. Changes in appetite, plasma fatty acid profiles and inflammatory markers were measured at baseline and at 12 weeks.

Results:  The mean (SD) increase in percent plasma eicosapentaenoic acid was statistically significant [1.1 (0.8) to 4.1 (2.2), P < 0.001], which was a strong indicator of good adherence. There were trends towards reductions in peptide YY (−9%; P = 0.078) and an increase in subjective sensations of hunger (+12%; P = 0.406), which reflects an increase in motivation to eat. Males (n = 13) experienced a more marked increase in hunger compared to females (+23% versus −6%), which was associated with maintenance in C‐reactive protein and interleukin‐6, and a reduction in soluble intercellular adhesion molecule‐1.

Conclusions:  The results obtained demonstrate meaningful trends towards improvements in subjective appetite and certain inflammatory markers (although no change in dietary intake) and this effect was more pronounced in males. However, the levels of some inflammatory markers increased in females and this requires further study. The high level of adherence achieved indicates that an intervention requiring patients to consume four fish oil capsules per day is achievable. This was a short‐term study and the effects need to be confirmed in a randomised controlled trial.
Staying in the here‐and‐now: A pilot study on the use of dialectical behaviour therapy group skills training for forensic clients with intellectual disability
Authors: Sakdalan J. A. , Shaw J. , Collier V.
Published: April 2010

Background  Dialectic behaviour therapy (DBT) has been widely used with individuals diagnosed with borderline personality disorder who exhibit severe emotional and behavioural dysregulation. There is a paucity of research in assessing the effectiveness of DBT with forensic clients with intellectual disability (ID).

Methods  This pilot study aims to evaluate the effectiveness of the DBT group skills training programme adapted particularly for offenders with ID. Six participants completed the 13‐week adapted DBT group skills training programme. All participants exhibited challenging behaviours and have a history of prior charges or convictions for violent crimes. The study conducted pre‐ and post‐tests using instruments that measured dynamic risks, relative strengths, coping skills and global functioning.

Results  The study result showed improvement across all measures. A decrease in the level of risks, increase in relative strengths and general improvement in overall functioning were found significant. The results were promising particularly as a stand‐alone adapted DBT group skills training programme for this client group.
Profiling in resolving inflammatory exudates identifies novel anti‐inflammatory and pro‐resolving mediators and signals for termination
Authors: Norling L. V. , Serhan C. N.
Published: April 2010

Abstract.  Norling LV, Serhan CN (Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA). Profiling in resolving inflammatory exudates identifies novel anti‐inflammatory and pro‐resolving mediators and signals for termination (Review). J Intern Med 2010; 268:15–24.

A highly orchestrated inflammatory response and its completion, termed resolution, are essential for ongoing health. Thus, complete understanding of the cellular and molecular events that govern natural resolution is vital. Using an unbiased systems approach to profile self‐limited inflammatory exudates, we identified a novel genus of specialized pro‐resolving lipid mediators (SPMs) comprised of three new families coined the resolvins, protectins and most recently the maresins biosynthesized from ω‐3 fatty acids. These join the lipoxin‐ and aspirin‐triggered lipoxins as anti‐inflammatory and pro‐resolving lipid mediators formed from arachidonic acid with the genus. SPMs have proven stereoselective, and control both the duration and magnitude of inflammation. Mapping these endogenous resolution circuits provides new avenues to probe the molecular basis of many widely occurring diseases where uncontrolled inflammation is characteristic. The focus of this JIM review is to depict recent advances from studies by the authors and colleagues on the biosynthesis and actions of these novel anti‐inflammatory, pro‐resolving and protective lipid mediators. Together these findings indicate that defective mechanisms and pathways in resolution may underlie our current appreciation of the inflammatory phenotype(s) that characterize some prevalent human diseases.
Neutrophil granules in health and disease
Authors: Häger M. , Cowland J. B. , Borregaard N.
Published: April 2010

Abstract.  Häger M, Cowland JB, Borregaard N (University of Copenhagen, Copenhagen, Denmark). Neutrophil granules in health and disease (Review). J Intern Med 2010; 268:25–34.

Neutrophil granules store proteins that are critically important for the neutrophil to move from the vascular bed to tissues and to kill microorganisms. This is illustrated in nature when individual proteins are deleted due to inherited mutations of their cognate genes, and such deficiencies result in the conditions leucocyte adhesion deficiency and chronic granulomatous disease. The granules of the neutrophil have traditionally been divided into two or three major types but are instead a continuum where several subtypes can be identified with differences in protein content and propensity for mobilization. This is explained by the ‘targeting by timing hypothesis’ which states that granules are filled with granule proteins that are synthesized at the time the granule is formed. The heterogeneity of granules arises because the synthesis of granule proteins is individually controlled and major differences exist in the timings of biosynthesis during granulocytopoiesis. This is largely controlled by gene transcription.
Microsomal prostaglandin E synthase‐1 and 5‐lipoxygenase: potential drug targets in cancer
Authors: Rådmark O. , Samuelsson B.
Published: April 2010

Abstract.  Rådmark O, Samuelsson B (Karolinska Institutet, Stockholm, Sweden). Microsomal prostaglandin Esynthase‐1 and 5‐lipoxygenase: potential drug targets in cancer (Review). J Intern Med 2010; 268:5–14.

There is strong evidence for a role of prostaglandin (PG)E2 in cancer cell proliferation and tumour development. In PGE2 biosynthesis, cyclooxygenases (COX‐1/2) convert arachidonic acid to PGH2, which can be isomerized to PGE2 by PGE synthases, including microsomal PGE synthase‐1 (MPGES‐1). Data describing genetic deletions of MPGES‐1 are reviewed. The results suggest that MPGES‐1 is an alternative therapeutic target for cancer cells and tumours that express this enzyme. Several compounds that target COX‐2 or MPGES‐1 also inhibit 5‐lipoxygenase. This may be advantageous for treatment of some forms of cancer.
Low temperature and anhydrous electron microscopy techniques to observe the infection process of the bacterial pathogen Xanthomonas fragariae on strawberry leaves
Authors: ALLAN‐WOJTAS P. , HILDEBRAND P.D. , BRAUN P.G. , SMITH‐KING H.L. , CARBYN S. , RENDEROS W.E.
Published: April 2010

Preserving the structural arrangement of the components of a bacterial infection process within a plant for microscopy study is a technical challenge because of the different requirements of each component for optimal preservation and visualization. We used low temperature scanning electron microscopy (cryo‐SEM), anhydrous fixation at ambient temperature and freeze‐substitution for transmission electron microscopy to examine fractured and sectioned strawberry leaves infected with Xanthomonas fragariae. Cryo‐SEM images of fractured samples showed the bacterial colonization of mesophyll air spaces in the leaf, limited by the vascular bundles and the orientation and packing of bacteria in extracellular polysaccharide. Transmission electron microscopy of samples fixed using osmium tetroxide dissolved in FC‐72 solvent at ambient temperature showed that the entire plant/bacteria/extracellular polysaccharide system was preserved in situ, and showed plasmolysis of mesophyll cells and disruption of organelles. In freeze‐substitution samples, osmium tetroxide in FC‐72 solvent gave superior preservation of the extracellular polysaccharide as compared to a conventional cocktail. In addition, strands believed to be xanthan were preferentially contrasted to show their density and orientation around the bacterial cells. We conclude that anhydrous fixation using osmium tetroxide in FC‐72 at ambient temperature gave the best preservation of the entire system, and freeze‐substitution using this same fixative enhanced the visualization of strands in the biofilm.
Automated focusing in bright‐field microscopy for tuberculosis detection
Authors: OSIBOTE O.A. , DENDERE R. , KRISHNAN S. , DOUGLAS T.S.
Published: April 2010

Automated microscopy to detectMycobacterium tuberculosisin sputum smear slides would enable laboratories in countries with a high tuberculosis burden to cope efficiently with large numbers of smears. Focusing is a core component of automated microscopy, and successful autofocusing depends on selection of an appropriate focus algorithm for a specific task. We examined autofocusing algorithms for bright‐field microscopy of Ziehl–Neelsen stained sputum smears. Six focus measures, defined in the spatial domain, were examined with respect to accuracy, execution time, range, full width at half maximum of the peak and the presence of local maxima. Curve fitting around an estimate of the focal plane was found to produce good results and is therefore an acceptable strategy to reduce the number of images captured for focusing and the processing time. Vollath's F4measure performed best for full z‐stacks, with a mean difference of 0.27 μm between manually and automatically determined focal positions, whereas it is jointly ranked best with the Brenner gradient for curve fitting.
The LysR‐type regulator QseA regulates both characterized and putative virulence genes in enterohaemorrhagic Escherichia coli O157:H7
Authors: Kendall Melissa M. , Rasko David A. , Sperandio Vanessa
Published: April 2010

Enterohaemorrhagic Escherichia coli (EHEC) colonizes the large intestine, causing attaching and effacing (AE) lesions. Most of the genes involved in AE lesion formation are encoded within a chromosomal pathogenicity island termed the locus of enterocyte effacement (LEE). The LysR‐type transcriptional factor QseA regulates the LEE by binding to the regulatory region of ler. We performed transcriptome analyses comparing wild‐type (WT) EHEC and the qseA mutant to elucidate QseA's role in gene regulation. During both growth phases, several genes carried in O‐islands were activated by QseA, whereas genes involved in cell metabolism were repressed. During late‐logarithmic growth, QseA activated expression of the LEE genes as well as non‐LEE‐encoded effector proteins. We also performed electrophoretic mobility shift assays, competition experiments and DNase I footprints. The results demonstrated that QseA directly binds both the ler proximal and distal promoters, its own promoter, as well as promoters of genes encoded in EHEC‐specific O‐islands. Additionally, we mapped the transcriptional start site of qseA, leading to the identification of two promoter sequences. Taken together, these results indicate that QseA acts as a global regulator in EHEC, co‐ordinating expression of virulence genes.
PavB is a surface‐exposed adhesin of Streptococcus pneumoniae contributing to nasopharyngeal colonization and airways infections
Authors: Jensch Inga , Gámez Gustavo , Rothe Michael , Ebert Sandra , Fulde Marcus , Somplatzki Daniela , Bergmann Simone , Petruschka Lothar , Rohde Manfred , Nau Roland , Hammerschmidt Sven
Published: April 2010

The genomic analysis of Streptococcus pneumoniae strains identified the Pneumococcal adherence and virulence factor B (PavB), whose repetitive sequences, designated Streptococcal Surface REpeats (SSURE), interact with human fibronectin. Here, we showed the gene in all tested pneumococci and identified that the observed differences in the molecular mass of PavB rely on the number of repeats, ranging from five to nine SSURE. PavB interacted with fibronectin and plasminogen in a dose‐dependent manner as shown by using various SSURE peptides. In addition, we identified PavB as colonization factor. Mice infected intranasally with ΔpavB pneumococci showed significantly increased survival times compared with wild‐type bacteria. Importantly, the pavB‐mutant showed a delay in transmigration to the lungs as observed in real‐time using bioluminescent pneumococci and decreased colonization rates in a nasopharyngeal carriage model. In co‐infection experiments the wild‐type out‐competed the pavB‐mutant and infections of epithelial cells demonstrated that PavB contributes to adherence to host cell. Blocking experiments suggested a function of PavB as adhesin, which was confirmed by direct binding of SSURE peptides to host cells. Finally, PavB may represent a new vaccine candidate as SSURE peptides reacted with human sera. Taken together, PavB is a surface‐exposed adhesin, which contributes to pneumococcal colonization and infections of the respiratory airways.
Pneumococcal microbial surface components recognizing adhesive matrix molecules targeting of the extracellular matrix
Authors: Paterson Gavin K. , Orihuela Carlos J.
Published: April 2010

The attachment of bacteria to host cells and tissues, and their subsequent invasion and dissemination are key processes during pathogenesis. In this issue of Molecular Microbiology, Jensch and co‐workers provide further molecular insight into these events during infection with the Gram positive bacterium Streptococcus pneumoniae. Their characterization of pneumococcal adherence and virulence factor B (PavB), a bacterial surface protein with orthologues in other streptococci, show that it binds to the extracellar matrix components fibronection and plasminogen by virtue of repetitive sequences‐designated streptococcal surface repeats. In mice, a pavB mutant showed reduced nasopharyngeal colonization and was attenuated in a lung infection model. As discussed here in the context of the pneumococcus, the study of PavB highlights the central role during microbal pathogenesis of targetting the extracellular matrix by so‐called microbial surface components recognizing adhesive matrix molecules (MSCRAMMs).
Hyperosmosis enhances radiation and hydroxyurea resistance of Schizosaccharomyces pombe checkpoint mutants through the spindle checkpoint and delayed cytokinesis
Authors: Alao John P. , Huis in 't Veld Pim J. , Buhse Frederike , Sunnerhagen Per
Published: April 2010

The DNA damage and stress response pathways interact to regulate cellular responses to genotoxins and environmental stresses. How these pathways interact in Schizosaccharomyces pombe is not well understood. We demonstrate that osmotic stress suppresses the DNA damage sensitivity of checkpoint mutants, and that this occurs through three distinct cell cycle delays. A delay in G2/M is dependent on Srk1. Progression through mitosis is halted by the Mad2‐dependent spindle checkpoint. Finally, cytokinesis is impaired by modulating Cdc25 expression. These three delays, imposed by osmotic stress, together compensate for the loss of checkpoint signalling.
Changes in diurnal patterns within the Populus transcriptome and metabolome in response to photoperiod variation
Authors: HOFFMAN DANIEL E. , JONSSON PÄR , BYLESJÖ MAX , TRYGG JOHAN , ANTTI HENRIK , ERIKSSON MARIA E. , MORITZ THOMAS
Published: April 2010

Changes in seasonal photoperiod provides an important environmental signal that affects the timing of winter dormancy in perennial, deciduous, temperate tree species, such as hybrid aspen (Populus tremula × Populus tremuloides). In this species, growth cessation, cold acclimation and dormancy are induced in the autumn by the detection of day‐length shortening that occurs at a given critical day length. Important components in the detection of such day‐length changes are photoreceptors and the circadian clock, and many plant responses at both the gene regulation and metabolite levels are expected to be diurnal. To directly examine this expectation and study components in these events, here we report transcriptomic and metabolomic responses to a change in photoperiod from long to short days in hybrid aspen. We found about 16% of genes represented on the arrays to be diurnally regulated, as assessed by our pre‐defined criteria. Furthermore, several of these genes were involved in circadian‐associated processes, including photosynthesis and primary and secondary metabolism. Metabolites affected by the change in photoperiod were mostly involved in carbon metabolism. Taken together, we have thus established a molecular catalog of events that precede a response to winter.
Nucleotide binding and dimerization at the chloroplast pre‐protein import receptor, atToc33, are not essential in vivo but do increase import efficiency
Authors: Aronsson Henrik , Combe Jonathan , Patel Ramesh , Agne Birgit , Martin Meryll , Kessler Felix , Jarvis Paul
Published: April 2010

The atToc33 protein is one of several pre‐protein import receptors in the outer envelope of Arabidopsis chloroplasts. It is a GTPase with motifs characteristic of such proteins, and its loss in the plastid protein import 1 (ppi1) mutant interferes with the import of photosynthesis‐related pre‐proteins, causing a chlorotic phenotype in mutant plants. To assess the significance of GTPase cycling by atToc33, we generated several atToc33 point mutants with predicted effects on GTP binding (K49R, S50N and S50N/S51N), GTP hydrolysis (G45R, G45V, Q68A and N101A), both binding and hydrolysis (G45R/K49N/S50R), and dimerization or the functional interaction between dimeric partners (R125A, R130A and R130K). First, a selection of these mutants was assessed in vitro, or in yeast, to confirm that the mutations have the desired effects: in relation to nucleotide binding and dimerization, the mutants behaved as expected. Then, activities of selected mutants were tested in vivo, by assessing for complementation of ppi1 in transgenic plants. Remarkably, all tested mutants mediated high levels of complementation: complemented plants were similar to the wild type in growth rate, chlorophyll accumulation, photosynthetic performance, and chloroplast ultrastructure. Protein import into mutant chloroplasts was also complemented to >50% of the wild‐type level. Overall, the data indicate that neither nucleotide binding nor dimerization at atToc33 is essential for chloroplast import (in plants that continue to express the other TOC receptors in native form), although both processes do increase import efficiency. Absence of atToc33 GTPase activity might somehow be compensated for by that of the Toc159 receptors. However, overexpression of atToc33 (or its close relative, atToc34) in Toc159‐deficient plants did not mediate complementation, indicating that the receptors do not share functional redundancy in the conventional sense.
Staphylococcus aureus invades the epithelium in nasal polyposis and induces IL‐6 in nasal epithelial cells in vitro
Authors: Sachse F. , Becker K. , Von Eiff C. , Metze D. , Rudack C.
Published: April 2010

To cite this article: Sachse F, Becker K, von Eiff C, Metze D, Rudack C. Staphylococcus aureus invades the epithelium in nasal polyposis and induces IL‐6 in nasal epithelial cells in vitro. Allergy 2010; 65: 1430–1437.

Background:  Staphylococcus aureus has been associated with chronic rhinosinusitis with nasal polyps (CRSwNP) pathogenesis but its role is still controversially discussed. Here, we demonstrate S. aureus detection in the mucosa of CRSwNP. In addition, intracellular residency of S. aureus in nasal polyp epithelial cells (NPECs) and its capability to induce TH‐2 cytokines were analyzed in vitro.

Methods:  Staphylococcus aureus detection in CRSwNP (n = 25), CRS without polyps (CRSsNP, n = 5), and turbinate mucosa (TM, n = 10) was performed by peptide nucleic acid‐fluorescence in situ hybridization (PNA‐FISH) and microbial cultivation from tissue biopsies. Intracellular residency was examined by intracellular persistence assay and electron microscopy. IL‐6 and IL‐13 responses to S. aureus infection and supernatants were quantified by ELISA.

Results:  Peptide nucleic acid‐fluorescence in situ hybridization positive bacterial cells were significantly increased in the epithelium of CRSwNP (17/25) compared to CRSsNP (0/5) and TM (1/10). Good concordance of PNA‐FISH results and S. aureus cultivation was found applying Cohen’s κ for CRSwNP (κ = 0.841) and TM (κ = 1.0). Intracellular persistence assay with S. aureus strain Newman and its corresponding small‐colony variant mutant strain III33 demonstrated intracellular survival and replication of S. aureus within NPECs. Both S. aureus strains significantly induced IL‐6 but not IL‐13 in infected NPECs and in NPECs challenged with corresponding staphylococcal supernatants.

Conclusion:  Invasion of the epithelium by S. aureus was a phenomenon seen predominantly in CRSwNP. Regardless of an intra‐ or extracellular localization in the epithelium, S. aureus is capable to induce IL‐6 synthesis in vitro and thus may contribute to the TH‐2 cytokine pattern in CRSwNP.
Prebiotic oligosaccharides: In vitro evidence for gastrointestinal epithelial transfer and immunomodulatory properties
Authors: Eiwegger Thomas , Stahl Bernd , Haidl Paul , Schmitt Joachim , Boehm Günther , Dehlink Eleonora , Urbanek Radvan , Szépfalusi Zsolt
Published: April 2010

Eiwegger T, Stahl B, Haidl P, Schmitt J, Boehm G, Dehlink E, Urbanek R, Szépfalusi Z. Prebiotic oligosaccharides: In vitro evidence for gastrointestinal epithelial transfer and immunomodulatory properties. Pediatr Allergy Immunol 2010: 21: 1179–1188. © 2010 John Wiley & Sons A/S

Prebiotic oligosaccharides are present in breast milk and evidence is pointing toward immunomodulatory properties of the acidic fraction. Recently, prebiotic supplements of infant formula [short‐chain galacto (scGOS)‐, long‐chain fructo (lcFOS)‐oligosaccharides] showed preventive effects on atopic disease development.

We aimed to define the direct immunologic effects of these oligosaccharides and of human (aHMOS) and cows’ milk (aCMOS) acidic oligosaccharides and to investigate the systemic uptake of prebiotic supplements of infant formula and a specific pectin‐derived acidic oligosaccharide hydrolysate (pAOS) in vitro.

After assurance of LPS‐free conditions (limulus assay, toll like receptor‐2, ‐4 transfected human embryonic kidney‐cells), in vitro‐transfer through a CaCo‐2 cell monolayer was measured using high‐pH anion exchange chromatography with pulsed amperometric detection. Direct effects on proliferation, cytokine‐induction of cord blood mononuclear cells and modulation of allergen‐specific CD4+ T‐cell cytokine profiles from allergic and non‐allergic individuals were investigated.

Transfer of scGOS/lcFOS and pAOS in‐vitro was detected with a rate of transfer of 4–14%, depending on the molecular size and structure. AHMOS induced IFN‐γ and IL‐10 but not the Th‐2 cytokine IL‐13 at physiologic concentrations (10–100 μg/ml) in cord blood, whereas aCMOS did not induce any of these cytokines. AHMOS significantly suppressed Th‐2 type cytokine‐production by Ara h1‐specific CD4+ T cells (CFSElow CD3+CD4+cells) from peanut allergic patients.

In conclusion, human milk‐derived acidic oligosaccharides may modulate postnatal allergen‐specific immune responses by the suppression of Th‐2‐type responses in atopy‐prone individuals. Moreover, there is in vitro evidence for epithelial transport of prebiotic oligosaccharides.
Psoriasis among Sarawakian natives in a tertiary skin centre in Sarawak
Authors: Yap Felix Boon‐Bin
Published: April 2010

A prospective cross‐sectional study was done between December 2007 and June 2009 in the skin clinic, Sarawak General Hospital, to determine the clinical characteristics of 138 Sarawakian natives with a clinical diagnosis of psoriasis. Women made up 50.7% and the mean age of the patients was 45.2 years. Of the group, 94.2% had chronic stable plaque psoriasis, 86.9% had a body surface area involvement of less than 10%, 60.9% had nail disease, 22.5% had joint disease and 55.1% had minimal effects to their quality of life because of their psoriasis.
Increased expression of ubiquitin‐specific protease 22 can promote cancer progression and predict therapy failure in human colorectal cancer
Authors: Liu Yan Long , Yang Yan Mei , Xu Hui , Dong Xin Shu
Published: April 2010

Background and Aims:  Increasing experimental evidence suggests that ubiquitin‐specific protease 22 (USP22) could exhibit a critical function in pathological processes, including oncogenesis and cell cycle progression. The aim of this study was to investigate the role of USP22 and the association with its potential targets in colorectal cancer (CRC).

Methods:  We evaluated the implication of USP22 and the candidate targets, such as B‐cell‐specific murine leukemia virus integration site‐1 (BMI‐1), cellular homolog of avian myelocytomatosis virus oncogene (c‐Myc), cyclin D2, inhibiter of cyclin‐dependent kinase (CDK) 4 (p16INK4a), and an alternate reading frame product of the CDKN2A locus (p14ARF), in matched samples comprising carcinoma and adjacent non‐cancerous mucosa from 82 patients with CRC using quantitative reverse transcription–polymerase chain reaction and immunostaining analyses.

Results:  The USP22 mRNA expression in the CRC tissues was significantly higher than those in the non‐cancerous mucosa tissues (P < 0.0001). Increased mRNA expression of USP22 was associated with advanced American Joint Committee on Cancer stage (P = 0.033) and high likelihood of therapy failure after radical resection (P < 0.0001). The Cox regression analysis revealed that the USP22 mRNA expression level was a significant factor for predicting prognosis (P < 0.0001). The statistical correlation analysis in mRNA levels showed that USP22 was strongly correlated with BMI‐1 (r = 0.790, P < 0.0001), c‐Myc (r = 0.528, P < 0.0001), and cyclin D2 (r = 0.657, P < 0.0001), but not p16INK4a (r = 0.103, P = 0.358) or p14ARF (r = −0.039, P = 0.731).

Conclusion:  Our results indicate that activation of USP22 correlates with CRC progression and therapy failure. Additionally, the oncogenic role of USP22 in the progression of CRC can be mechanistically linked with BMI‐1, c‐Myc, and cyclin D2, but not with p16INK4a and p14ARF.
Asian consensus on irritable bowel syndrome
Authors: Gwee Kok‐Ann , Bak Young‐Tae , Ghoshal Uday Chand , Gonlachanvit Sutep , Lee Oh Young , Fock Kwong Ming , Chua Andrew Seng Boon , Lu Ching‐Liang , Goh Khean‐Lee , Kositchaiwat Chomsri , Makharia Govind , Park Hyo‐Jin , Chang Full‐Young , Fukudo Shin , Choi Myung‐Gyu , Bhatia Shobna , Ke Meiyun , Hou Xiaohua , Hongo Michio
Published: April 2010

Background and Aims:  Many of the ideas on irritable bowel syndrome (IBS) are derived from studies conducted in Western societies. Their relevance to Asian societies has not been critically examined. Our objectives were to bring to attention important data from Asian studies, articulate the experience and views of our Asian experts, and provide a relevant guide on this poorly understood condition for doctors and scientists working in Asia.

Methods:  A multinational group of physicians from Asia with special interest in IBS raised statements on IBS pertaining to symptoms, diagnosis, epidemiology, infection, pathophysiology, motility, management, and diet. A modified Delphi approach was employed to present and grade the quality of evidence, and determine the level of agreement.

Results:  We observed that bloating and symptoms associated with meals were prominent complaints among our IBS patients. In the majority of our countries, we did not observe a female predominance. In some Asian populations, the intestinal transit times in healthy and IBS patients appear to be faster than those reported in the West. High consultation rates were observed, particularly in the more affluent countries. There was only weak evidence to support the perception that psychological distress determines health‐care seeking. Dietary factors, in particular, chili consumption and the high prevalence of lactose malabsorption, were perceived to be aggravating factors, but the evidence was weak.

Conclusions:  This detailed compilation of studies from different parts of Asia, draws attention to Asian patients' experiences of IBS.
Role of epoxide hydrolase 1 gene polymorphisms in esophageal cancer in a high‐risk area in India
Authors: Ihsan Rakhshan , Chattopadhyay Indranil , Phukan Rupkumar , Mishra Ashwani K , Purkayastha Joydeep , Sharma Jagannath , Zomawia Eric , Verma Yogesh , Mahanta Jagadish , Saxena Sunita , Kapur Sujala
Published: April 2010

Background and Aim:  Microsomal epoxide hydrolase 1 (EPHX1) is involved in the metabolism of environmental and tobacco carcinogens. Tobacco smoking, betel quid chewing, and alcohol consumption are the major known risk factors for esophageal cancer. The present case‐control study evaluated the influence of EPHX1 genetic variations on esophageal cancer susceptibility in 142 patients and 185 healthy controls from a high‐incidence region of India where tobacco use and alcohol consumption are widespread and the users of these two substances are also betel quid chewers.

Methods:  EPHX1 polymorphic alleles (exon 3, Tyr113His and exon 4, His139Arg) were genotyped by polymerase chain reaction–restriction fragment length polymorphism method and direct sequencing. The results were analyzed using logistic regression to calculate odds ratios (OR) and confidence intervals (CI).

Results:  Patients with exon 4 genotypes (139His/Arg, 139Arg/Arg) and the 139Arg allele were significantly associated with a risk of esophageal cancer (ORHis139Arg 1.887, 95% CI = 1.112–3.201, P = 0.019; ORArg139Arg 7.140, 95% CI = 1.276–393.953, P = 0.025 and ORArg 1.83, 95% CI = 1.19–2.82, P = 0.003). The 139His/Arg genotype was a significant risk factor for esophageal cancer in tobacco chewers and betel quid chewers. Patients with the 139Arg/Arg genotype were at significantly higher risk for developing a well‐differentiated and moderately‐differentiated grade of tumor. In contrast, the 113His/His genotype of exon 3 was a significant protective factor for esophageal cancer in tobacco smokers (OR 0.291, 95% CI = 0.138–0.616, P = 0.001), betel quid chewers (OR 0.434, 95% CI = 0.236–0.797, P = 0.007), and alcohol users.

Conclusion:  EPHX1 exon 4 139His/Arg, and 139Arg/Arg genotypes were associated with a higher risk of esophageal cancer in a high‐risk area of India.