bluuebunny/crossref_metadata_2025 huggingface dataset:
Duration of estrogen deprivation, not chronological age, prevents estrogen's ability to enhance hippocampal synaptic physiology
Authors: Smith Caroline C. , Vedder Lindsey C. , Nelson Amy R. , Bredemann Teruko M. , McMahon Lori L.
Published: October 2010

Whether estrogen replacement is beneficial to cognitive health is controversial. Some studies have shown that estrogen replacement therapy (ERT) relieves memory impairment associated with menopause in women, whereas others suggest that estrogen not only is incapable of providing a benefit, but actually can be detrimental. One possible explanation for this discrepancy in study findings could be the varying time after menopause at which ERT is initiated. It has been proposed that a critical period exists during which ERT must be administered to enhance cognitive function. This idea has yet to be tested directly using functional synaptic studies, however. Here we investigated whether prolonged hormone deprivation caused by ovariectomy (OVX) in young adult rats prevents the ability of estrogen replacement to increase synaptic function in the hippocampus to a degree necessary for estrogen-induced improvement in learning and memory. Remarkably, estrogen replacement was found to increase long-term potentiation, the current mediated by NR2B-containing NMDA receptors, and the dendritic spine density at CA3–CA1 synapses up to 15 months post-OVX. However, by 19 months post-OVX, the same estrogen replacement was unable to induce these changes. Importantly, this loss of estrogen's effectiveness was seen to be a consequence of the duration of deprivation. In female rats aged with their ovaries intact and examined at the same chronological age as the 19-month post-OVX group, estrogen replacement significantly increased synaptic function and spine density. These data clearly demonstrate that a critical period exists during which ERT must be administered, and that once this period passes, the beneficial effects are lost.
Filament structure of bacterial tubulin homologue TubZ
Authors: Aylett Christopher H. S. , Wang Qing , Michie Katharine A. , Amos Linda A. , Löwe Jan
Published: October 2010

Low copy number plasmids often depend on accurate partitioning systems for their continued survival. Generally, such systems consist of a centromere-like region of DNA, a DNA-binding adaptor, and a polymerizing cytomotive filament. Together these components drive newly replicated plasmids to opposite ends of the dividing cell. The
Bacillus thuringiensis
plasmid pBToxis relies on a filament of the tubulin/FtsZ-like protein TubZ for its segregation. By combining crystallography and electron microscopy, we have determined the structure of this filament. We explain how GTP hydrolysis weakens the subunit–subunit contact and also shed light on the partitioning of the plasmid–adaptor complex. The double helical superstructure of TubZ filaments is unusual for tubulin-like proteins. Filaments of ParM, the actin-like partitioning protein, are also double helical. We suggest that convergent evolution shapes these different types of cytomotive filaments toward a general mechanism for plasmid separation.
Rubicon controls endosome maturation as a Rab7 effector
Authors: Sun Qiming , Westphal Wiebke , Wong Kwun Ngok , Tan Irena , Zhong Qing
Published: October 2010

The activation and recruitment of the small GTPase Rab7 to early endosome is a critical step for early to late endosome maturation, a process that requires the class III phosphatidylinositol 3-kinase (PI3KC3) and GTPase regulators. However, the molecular mechanism underlying Rab7 activation and endosome maturation is still poorly defined. Here we report that Rubicon, a component of the PI3KC3 complex, prevents endosome maturation through differential interactions with Rab7 and UVRAG. UVRAG activates PI3KC3 and C-VPS/HOPS, a guanine nucleotide exchange factor that catalyzes the exchange of GDP for GTP on Rab7. We demonstrate that Rubicon sequesters UVRAG from C-VPS/HOPS. Active GTP-bound Rab7 competes for Rubicon binding and releases UVRAG to associate with C-VPS/HOPS, which in turn promotes further loading of Rab7 with GTP. This feed-forward loop ensures rapid amplification of GTP-bound Rab7 and consequent stimulation of endosome maturation. Hence, Rubicon serves as a previously unknown Rab7 effector to ensure the proper progression of the endocytic pathway.
Identification of a receptor for an extinct virus
Authors: Soll Steven J. , Neil Stuart J. D. , Bieniasz Paul D.
Published: October 2010

The resurrection of endogenous retroviruses from inactive molecular fossils has allowed the investigation of interactions between extinct pathogens and their hosts that occurred millions of years ago. Two such paleoviruses, chimpanzee endogenous retrovirus-1 and -2 (CERV1 and CERV2), are relatives of modern MLVs and are found in the genomes of a variety of Old World primates, but are absent from the human genome. No extant CERV1 and -2 proviruses are known to encode functional proteins. To investigate the host range restriction of these viruses, we attempted to reconstruct functional envelopes by generating consensus genes and proteins. CERV1 and -2 enveloped MLV particles infected cell lines from a range of mammalian species. Using CERV2 Env-pseudotyped MLV reporters, we identified copper transport protein 1 (CTR1) as a receptor that was presumably used by CERV2 during its ancient exogenous replication in primates. Expression of human CTR1 was sufficient to confer CERV2 permissiveness on otherwise resistant hamster cells, and CTR1 knockdown or CuCl
2
treatment specifically inhibited CERV2 infection of human cells. Mutations in highly conserved CTR1 residues that have rendered hamster cells resistant to CERV2 include a unique deletion in a copper-binding motif. These CERV2 receptor-inactivating mutations in hamster CTR1 are accompanied by apparently compensating changes, including an increased number of extracellular copper-coordinating residues, and this may represent an evolutionary barrier to the acquisition of CERV2 resistance in primates.
The
Vibrio cholerae
type VI secretion system displays antimicrobial properties
Authors: MacIntyre Dana L. , Miyata Sarah T. , Kitaoka Maya , Pukatzki Stefan
Published: October 2010

The acute diarrheal disease cholera is caused by the marine bacterium
Vibrio cholerae
. A type VI secretion system (T6SS), which is structurally similar to the bacteriophage cell-puncturing device, has been recently identified in
V. cholerae
and is used by this organism to confer virulence toward phagocytic eukaryotes, such as J774 murine macrophages and
Dictyostelium discoideum
. We tested the interbacterial virulence of
V. cholerae
strain V52, an O37 serogroup with a constitutively active T6SS. V52 was found to be highly virulent toward multiple Gram-negative bacteria, including
Escherichia coli
and
Salmonella
Typhimurium, and caused up to a 100,000-fold reduction in
E. coli
survival. Because the T6SS-deficient mutants V52Δ
vasK
and V52Δ
vasH
showed toxicity defects that could be complemented, virulence displayed by
V. cholerae
depends on a functional T6SS.
V. cholerae
V52 and strains of the O1 serogroup were resistant to V52, suggesting that
V. cholerae
has acquired immunity independently of its serogroup. We hypothesize that the T6SS, in addition to targeting eukaryotic host cells, confers toxicity toward other bacteria, providing a means of interspecies competition to enhance environmental survival. Thus, the
V. cholerae
T6SS may enhance the survival of
V. cholerae
in its aquatic ecosystem during the transmission of cholera and between epidemics.
Intrinsic apurinic/apyrimidinic (AP) endonuclease activity enables
Bacillus subtilis
DNA polymerase X to recognize, incise, and further repair abasic sites
Authors: Baños Benito , Villar Laurentino , Salas Margarita , de Vega Miguel
Published: October 2010

The
N
-glycosidic bond can be hydrolyzed spontaneously or by glycosylases during removal of damaged bases by the base excision repair pathway, leading to the formation of highly mutagenic apurinic/apyrimidinic (AP) sites. Organisms encode for evolutionarily conserved repair machinery, including specific AP endonucleases that cleave the DNA backbone 5′ to the AP site to prime further DNA repair synthesis. We report on the DNA polymerase X from the bacterium
Bacillus subtilis
(PolX
Bs
) that, along with polymerization and 3′–5′-exonuclease activities, possesses an intrinsic AP-endonuclease activity. Both, AP-endonuclease and 3′–5′-exonuclease activities are genetically linked and governed by the same metal ligands located at the C-terminal polymerase and histidinol phosphatase domain of the polymerase. The different catalytic functions of PolX
Bs
enable it to perform recognition and incision at an AP site and further restoration (repair) of the original nucleotide in a standalone AP-endonuclease-independent way.
The tumor-associated EpCAM regulates morphogenetic movements through intracellular signaling
Authors: Maghzal Nadim , Vogt Emily , Reintsch Wolfgang , Fraser James S. , Fagotto François
Published: October 2010

Epithelial cell adhesion molecule (EpCAM) is best known as a tumor-associated protein highly expressed in carcinomas. The function of this cell surface protein during embryonic development and its potential role in cancer are still poorly understood. We identified EpCAM in a gain-of-function screen for inducers of abnormal tissue mixing during gastrulation. Elevated EpCAM levels in either the ectoderm or the mesoderm confer “invasive” properties to cells in both populations. We found that this phenotype represents an “overstimulation” of an essential activity of EpCAM in controlling cell movements during embryonic development. Surprisingly, this property is independent of the putative adhesive function of EpCAM, and rather relies on a novel signaling function that operates through down-regulation of PKC activity. We show that inhibition of novel PKCs accounts entirely for the invasive phenotype induced by abnormally high levels of EpCAM as well as for its normal function in regulating cell rearrangement during early development.
Quality control for unfolded proteins at the plasma membrane
Authors: Apaja Pirjo M. , Xu Haijin , Lukacs Gergely L.
Published: October 2010

Cellular protein homeostasis profoundly depends on the disposal of terminally damaged polypeptides. To demonstrate the operation and elucidate the molecular basis of quality control of conformationally impaired plasma membrane (PM) proteins, we constructed CD4 chimeras containing the wild type or a temperature-sensitive bacteriophage λ domain in their cytoplasmic region. Using proteomic, biochemical, and genetic approaches, we showed that thermal unfolding of the λ domain at the PM provoked the recruitment of Hsp40/Hsc70/Hsp90 chaperones and the E2–E3 complex. Mixed-chain polyubiquitination, monitored by bioluminescence resonance energy transfer and immunoblotting, is responsible for the nonnative chimera–accelerated internalization, impaired recycling, and endosomal sorting complex required for transport–dependent lysosomal degradation. A similar paradigm prevails for mutant dopamine D4.4 and vasopressin V2 receptor removal from the PM. These results outline a peripheral proteostatic mechanism in higher eukaryotes and its potential contribution to the pathogenesis of a subset of conformational diseases.
Extracellular NAD+ shapes the Foxp3+ regulatory T cell compartment through the ART2–P2X7 pathway
Authors: Hubert Sandra , Rissiek Björn , Klages Katjana , Huehn Jochen , Sparwasser Tim , Haag Friedrich , Koch-Nolte Friedrich , Boyer Olivier , Seman Michel , Adriouch Sahil
Published: October 2010

CD4+CD25+FoxP3+ regulatory T cells (T reg cells) play a major role in the control of immune responses but the factors controlling their homeostasis and function remain poorly characterized. Nicotinamide adenine dinucleotide (NAD+) released during cell damage or inflammation results in ART2.2–mediated ADP-ribosylation of the cytolytic P2X7 receptor on T cells. We show that T reg cells express the ART2.2 enzyme and high levels of P2X7 and that T reg cells can be depleted by intravenous injection of NAD+. Moreover, lower T reg cell numbers are found in mice deficient for the NAD-hydrolase CD38 than in wild-type, P2X7-deficient, or ART2-deficient mice, indicating a role for extracellular NAD+ in T reg cell homeostasis. Even routine cell preparation leads to release of NAD+ in sufficient quantities to profoundly affect T reg cell viability, phenotype, and function. We demonstrate that T reg cells can be protected from the deleterious effects of NAD+ by an inhibitory ART2.2-specific single domain antibody. Furthermore, selective depletion of T reg cells by systemic administration of NAD+ can be used to promote an antitumor response in several mouse tumor models. Collectively, our data demonstrate that NAD+ influences survival, phenotype, and function of T reg cells and provide proof of principle that acting on the ART2–P2X7 pathway represents a new strategy to manipulate T reg cells in vivo.
Proliferating cell nuclear antigen acts as a cytoplasmic platform controlling human neutrophil survival
Authors: Witko-Sarsat Véronique , Mocek Julie , Bouayad Dikra , Tamassia Nicola , Ribeil Jean-Antoine , Candalh Céline , Davezac Noélie , Reuter Nathalie , Mouthon Luc , Hermine Olivier , Pederzoli-Ribeil Magali , Cassatella Marco A.
Published: October 2010

Neutrophil apoptosis is a highly regulated process essential for inflammation resolution, the molecular mechanisms of which are only partially elucidated. In this study, we describe a survival pathway controlled by proliferating cell nuclear antigen (PCNA), a nuclear factor involved in DNA replication and repairing of proliferating cells. We show that mature neutrophils, despite their inability to proliferate, express high levels of PCNA exclusively in their cytosol and constitutively associated with procaspases, presumably to prevent their activation. Notably, cytosolic PCNA abundance decreased during apoptosis, and increased during in vitro and in vivo exposure to the survival factor granulocyte colony-stimulating factor (G-CSF). Peptides derived from the cyclin-dependent kinase inhibitor p21, which compete with procaspases to bind PCNA, triggered neutrophil apoptosis thus demonstrating that specific modification of PCNA protein interactions affects neutrophil survival. Furthermore, PCNA overexpression rendered neutrophil-differentiated PLB985 myeloid cells significantly more resistant to TNF-related apoptosis-inducing ligand– or gliotoxin-induced apoptosis. Conversely, a decrease in PCNA expression after PCNA small interfering RNA transfection sensitized these cells to apoptosis. Finally, a mutation in the PCNA interdomain-connecting loop, the binding site for many partners, significantly decreased the PCNA-mediated antiapoptotic effect. These results identify PCNA as a regulator of neutrophil lifespan, thereby highlighting a novel target to potentially modulate pathological inflammation.
Epithelial reticulon 4B (Nogo-B) is an endogenous regulator of Th2-driven lung inflammation
Authors: Wright Paulette L. , Yu Jun , Di Y.P. Peter , Homer Robert J. , Chupp Geoffrey , Elias Jack A. , Cohn Lauren , Sessa William C.
Published: October 2010

Nogo-B is a member of the reticulon family of proteins (RTN-4B) that is highly expressed in lung tissue; however, its function remains unknown. We show that mice with Th2-driven lung inflammation results in a loss of Nogo expression in airway epithelium and smooth muscle compared with nonallergic mice, a finding which is replicated in severe human asthma. Mice lacking Nogo-A/B (Nogo-KO) display an exaggerated asthma-like phenotype, and epithelial reconstitution of Nogo-B in transgenic mice blunts Th2-mediated lung inflammation. Microarray analysis of lungs from Nogo-KO mice reveals a marked reduction in palate lung and nasal clone (PLUNC) gene expression, and the levels of PLUNC are enhanced in epithelial Nogo-B transgenic mice. Finally, transgenic expression of PLUNC into Nogo-KO mice rescues the enhanced asthmatic-like responsiveness in these KO mice. These data identify Nogo-B as a novel protective gene expressed in lung epithelia, and its expression regulates the levels of the antibacterial antiinflammatory protein PLUNC.
Productivity Orientation and the Consumption of Collectable Experiences
Authors: Keinan Anat , Kivetz Ran
Published: October 2010

This research examines why consumers desire unusual and novel consumption experiences and voluntarily choose leisure activities, vacations, and celebrations that are predicted to be less pleasurable. For example, consumers sometimes choose to stay at freezing ice hotels and to eat at restaurants serving peculiar foods, such as bacon ice cream. We propose that such choices are driven by consumers' continual striving to use time productively, make progress, and reach accomplishments (i.e., a productivity orientation). We argue that choices of collectable (unusual, novel, extreme) experiences lead consumers to feel productive even when they are engaging in leisure activities as they “check off” items on an “experiential check list” and build their “experiential CV.” A series of laboratory and field studies shows that the consumption of collectable experiences is driven and intensified by a (chronic or situational) productivity orientation.
Development of a Benchtop Baking Method for Chemically Leavened Crackers. I. Identification of a Diagnostic Formula and Procedure
Authors: Kweon Meera , Slade Louise , Levine Harry
Published: October 2010

A benchtop baking method has been developed to predict the contribution of gluten functionality to overall flour performance for chemically leavened crackers. To identify a diagnostic cracker formula, the effects of leavening system (sodium bicarbonate, monocalcium phosphate, and ammonium bicarbonate), sugar concentration (%S), and total solvent (TS) on cracker‐baking performance were explored. From preliminary experiments to establish a production procedure, 10 min of dough‐mixing time, a cord‐weave baking mesh, and a 500°F oven temperature were selected. For the leavening system, increasing ammonium bicarbonate (ABC) level at constant sodium bicarbonate (soda) and monocalcium phosphate (MCP) levels resulted in increased cracker height. For the diagnostic formula, 1.25 g of soda, 1.25 g of MCP, and 1.25 g of ABC were selected, based on 100 g of flour. As the sugar concentration in the cracker formula, at constant total solvent (38 TS), decreased to <20%, the resulting cracker dough became softer, and the baked cracker exhibited an increased blistering tendency because of a too‐high formula water level. In contrast, a cracker dough formulated with >40% sugar concentration was too crumbly to handle and sheet. As the total solvent in the cracker formula increased at constant sugar concentration (≈23.7%S), the resulting dough became softer. A dough with 34 TS was too crumbly to handle, while doughs with 42 and 46 TS were too soft to handle and resulted in blistering. Therefore, 38 TS and 23.7%S were identified for the diagnostic formula. Crackers baked with a hard wheat flour, a soft wheat flour, and blends validated the utility of the developed method.
Effect of Wheat Genotype and Environment on Relationships Between Dough Extensibility and Breadmaking Quality
Authors: Caffe‐Treml Melanie , Glover Karl D. , Krishnan Padmanaban G. , Hareland Gary A. , Bondalapati Krishna D. , Stein Jeff
Published: October 2010

Dough extensibility affects processing ease, gas retention, and loaf volume of finished products. The Kieffer dough extensibility test was developed to assess extensibility of small dough samples and is therefore adapted for use in breeding programs. Information is lacking on relationships between wheat growing environments and dough properties measured by the Kieffer dough extensibility test. This study documents the variability of dough extensibility (Ext), maximum resistance to extension (Rmax), and area under the extensibility curve (Area) in relation to breadmaking quality, and the effect of wheat growing environments. Mixograph, Kieffer dough extensibility, and bake tests were performed on flour milled from 19 hard red spring wheat (Triticum aestivum L.) genotypes grown during three growing seasons (2007‐2009) at six South Dakota locations. Although both genotype and environment had significant effects on Kieffer dough extensibility variables, environment represented the largest source of variation. Among genotype means, Area was most correlated (r = 0.63) with loaf volume, suggesting that by selecting lines with increased Area, loaf volume should improve. Rmax was positively correlated (r = 0.58) with loaf volume among genotype means but negatively correlated (r = –0.80) among environmental means. Ext was positively correlated (r = 0.90) with loaf volume among environmental means. Weather variables were correlated with Rmax, Ext and loaf volume and therefore could help predict end‐use quality.
Effects of LAB Fermentation on Physical Properties of Oat Flour and Its Suitability for Noodle Making
Authors: Wan Jingjing , Huang Weining , Zhong Jing , Huang Liqun , Rayas‐Duarte Patricia , Liu Bin
Published: October 2010

Flour was obtained from oats fermented with lactic acid bacteria (LAB) to study the effect of fermentation on the physical properties and the suitability of fermented oats for use in starch noodle production. The results showed that fermented samples had a significantly lower pH than control samples. Gel strength and amylose content initially increased and then decreased (P < 0.05) with fermentation time. The peak viscosity, breakdown, final viscosity, and setback value decreased with fermentation time. Fermented noodles showed a higher hardness and springiness. In particular, Lactobacillus plantarum (LP) induced the highest springiness, cohesiveness, gumminess, chewiness, and resilience over 12 hr of fermentation. The cooking quality evaluation indicated that fermentation improved the quality of oat starch noodles. Fermented oats resulted in noodles with low cooking loss and higher cooking weight compared to noodles made from fresh flour. The use of LP for 12 hr of fermentation time yielded noodles of the best quality.
Real-Time PCR Quantification of Peronospora arborescens, the Opium Poppy Downy Mildew Pathogen, in Seed Stocks and Symptomless Infected Plants
Authors: Montes-Borrego Miguel , Muñoz-Ledesma Francisco J. , Jiménez-Díaz Rafael M. , Landa Blanca B.
Published: October 2010

In this study, we developed a reliable, quick, and accurate quantitative polymerase chain reaction (qPCR) assay based on the MIQE (Minimum Information for publication of Quantitative Real-Time PCR Experiments) guidelines for the quantification of Peronospora arborescens in infected downy mildew–symptomless opium poppy (Papaver somniferum) tissues and commercial seed stocks. The protocol was highly reproducible and allowed accurate quantification of pathogen DNA up to 10 fg in different plant DNA backgrounds without losing specificity and efficiency. Moreover, to further overcome difficulties conferred by the strict biotrophy of this pathogen, we developed dilution series of DNA extracted from a plasmid with the target pathogen DNA as a cloned insert. This facilitated the demonstration of the robustness of the protocol in different laboratories with different qPCR equipment and reagents, which may help in its use on a broad scale. Finally, we validated the usefulness of the qPCR protocol for quarantine purposes and downy mildew resistance screening by quantifying P. arborescens in complex, naturally infested opium poppy samples. Thus, a pathogen biomass of 0.0003 to 0.007‰ or of 0.110 to 5,557 ppm was quantified in symptomless capsules in commercial seed stocks, or in stem samples from symptomless opium poppy plants systemically infected by the pathogen, respectively.
First Report of Oidium longipes as the Causal Agent of Petunia Powdery Mildew in the United Kingdom
Authors: Kiss L. , Bereczky Z.
Published: October 2010

In autumn 2009, during a survey of powdery mildews of solanaceous plants in the United Kingdom, petunia (Petunia × hybrida) plants showing typical symptoms of powdery mildew infections were repeatedly collected in East Malling, Rochester, and Sandringham, UK. Leaves, stems, and petals of the collected plants, grown as outdoor ornamentals, were covered by dense, sporulating, white mycelium. Conidia were ellipsoid-cylindrical, measured 20 to 30 × 10 to 15 μm, and were produced in chains. Germ tubes arose from the ends of conidia and terminated in simple, unlobed apices. Some of the conidiophores were extremely long, up to 250 μm, because the second or third cell, or sometimes the foot cell, was up to 105 to 170 μm long. Other conidiophores were shorter, with no exceptionally long cells, but all of them exhibited a few characteristics in common: their width increased from base to top, sometimes enlarging considerably at a particular point of the foot cell, and basal septa were usually located 7 to 30 μm from the point of branching. Hyphal appressoria were nipple shaped. The teleomorph stage was not found. On the basis of these characteristics, the fungus was identified as Oidium longipes, a recently described (4) and little known pathogen of petunia and other solanaceous plants (1,3). To support the identification of this fungus, DNA was extracted from conidia collected with sterile brushes from single leaves collected in Sandringham, East Malling, and Rochester with a Qiagen DNeasy Plant Kit (Qiagen, Hilden, Germany), and the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA was amplified and determined as described in Jankovics et al. (2). The three identical ITS sequences, deposited in GenBank under Accession Nos. HM156495, HM156496, and HM156497, were identical to several ITS sequences of O. longipes, such as AF250777, EU327324, and EU327325. This has also supported that the disease was caused by this species. Herbarium specimens were deposited under the Accession Nos. HAL 2373F, HAL 2374F, and HAL 2375F at the Herbarium of Martin Luther University, Halle, Germany. To our knowledge, this is the first report of O. longipes in the UK.

References: (1) A. Bolay. Cryptogam. Helv. 20:1, 2005. (2) T. Jankovics et al. Phytopathology 98:529, 2008. (3) L. Kiss et al. Plant Disease 92:818, 2008. (4) M. E. Noordeloos and W. M. Loerakker. Persoonia 14:51, 1989.
Genetic Diversity of Potato virus Y Infecting Tobacco Crops in China
Authors: Tian Y. P. , Liu J. L. , Zhang C. L. , Liu Y. Y. , Wang B. , Li X.-D. , Guo Z. K. , Valkonen J. P. T.
Published: October 2010

Genetic variability of Potato virus Y (PVY) isolates infecting potato has been characterized but little is known about genetic diversity of PVY isolates infecting tobacco crops. In this study, PVY isolates were collected from major tobacco-growing areas in China and single-lesion isolates were produced by serial inoculation on Chenopodium amaranticolor. Most isolates (88%) caused systemic veinal necrosis symptoms in tobacco. Of these, 16 isolates contained a PVYO-like coat protein (CP) and PVYN-like helper component proteinase (HC-pro) and, in this respect, were similar to the PVYN-Wi, PVYN:O, and PVY-HN2 isolates characterized from potato in Europe, the United States, and China, respectively; two isolates contained a PVYO-like HC-pro and a PVYN-like CP; another two isolates had recombination junctions in the CP-encoding region. Both the HC-pro and CP of PVY were under negative selection as a whole; however, seven amino acids in HC-pro and six amino acids in CP were under positive selection. Selection pressures differed between the subpopulations of PVY distinguished by phylogenetic analysis of HC-pro and CP sequences. When PVY isolates from potato were included, no host-specific clustering of the PVY isolates was observed in phylogenetic and nucleotide diversity analyses, suggesting frequent spread of PVY isolates between potato and tobacco crops in the field.
Effects of habitat modification on coastal fish assemblages
Authors: Wen C. K.‐C. , Pratchett M. S. , Shao K.‐T. , Kan K.‐P. , Chan B. K. K.
Published: October 2010

The purpose of this study was to assess the influence of anthropogenic modification of coastal habitats on fish assemblages in Taiwan, comparing the abundance, species richness and taxonomic composition of fishes on natural v. artificial habitats. While there was no significant variation in the abundance or richness of fishes between natural and artificial habitats, the species composition of fishes in artificial habitats was significantly different from that of natural habitats. Natural reefs were characterized by greater abundance of Stethojulis spp. (Labridae), Abudefduf spp. (Pomacentridae) and Thalassoma spp. (Labridae), whereas anthropogenic habitats were dominated by Parupeneus indicus (Mullidae), Pempheris oualensis (Pempheridae) and Parapriacanthus ransonneti (Pempheridae). In general, it appears that specialist reef‐associated species are being replaced with fishes that are much more generalist in their habitat‐use. The loss of natural coastal habitats may threaten some species that cannot live in anthropogenically altered habitats, though the overall abundance and diversity of coastal fishes was not significantly different between natural and artificial habitats in Taiwan.
Predictors and correlates of reduced frequency or cessation of injection drug use during a randomized HIV prevention intervention trial
Authors: Mackesy‐Amiti Mary E. , Ouellet Lawrence J. , Golub Elizabeth T. , Hudson Sharon , Hagan Holly , Garfein Richard S.
Published: October 2010

Aims  This study conducted a secondary analysis to examine injection cessation and decreasing frequency of injection during a multi‐site randomized controlled HIV prevention intervention trial that sought to reduce sexual and injection risk behavior among young injection drug users.

Design and Setting  A six‐session, cognitive–behavioral skills‐building intervention in which participants were taught peer education skills [peer education intervention (PEI)] was compared with a time‐equivalent attention control. Follow‐up interviews were conducted at 3 and 6 months post‐baseline.

Participants  Trial participants were HIV and hepatitis C virus (HCV) antibody‐negative injection drug users aged 15–30 years. Participants who had at least one follow‐up interview and reported injecting drugs in the previous 3 months at baseline were eligible for the present analysis (n = 690).

Measurements  At each interview, data were collected on the number of times participants injected drugs over the previous 3 months.

Findings  Twenty‐seven per cent of participants reported at least one 3‐month period of injection cessation. In a multivariate, zero‐inflated negative binomial regression adjusting for prior injection frequency, time of follow‐up and psychosocial variables, PEI trial arm and smaller session size were associated significantly with injection cessation. Trial arm had no effect on the frequency of injection among those who continued to inject.

Conclusions  HIV prevention interventions that encourage injection drug users to take on the role of peer educator may have the additional benefit of increasing the likelihood of injection cessation. Intervention group size is also an important consideration, with smaller groups having higher rates of cessation.
RNA‐binding motif protein 24 regulates myogenin expression and promotes myogenic differentiation
Authors: Jin Donghao , Hidaka Kyoko , Shirai Manabu , Morisaki Takayuki
Published: October 2010

The formation of muscle fibers involves sequential expression of many proteins that regulate key steps during myoblast‐to‐myotube transition. Myogenin is a major player in the initiation and maintenance of myogenic differentiation in a mouse myoblast cell line, C2C12. RNA‐binding proteins bind to specific target RNA sequences and regulate gene expression in a post‐transcriptional manner. This study demonstrates that RNA‐binding motif protein 24 (Rbm24) interacts with the 3′‐untranslated region of myogenin mRNA and affects its half‐life in C2C12 myogenesis. Knockdown of Rbm24 expression by RNA interference significantly decreased myogenin expression associated with the inhibition of myogenesis. In contrast, the overexpression of Rbm24 by stable transfection of a plasmid increased myogenin expression and had a positive effect on myogenic differentiation. Ectopic expression of myogenin was also able to restore myogenic differentiation in Rbm24‐knockdown cells. Together, our results suggest that Rbm24 binds to myogenin mRNA and regulates its stability in C2C12 cells. Rbm24 plays a crucial role in myogenic differentiation at least in part through a myogenin‐dependent post‐transcriptional regulatory pathway.
Possible solutions for barriers in incident reporting by residents
Authors: Martowirono Kartinie , Jansma José D. , van Luijk Scheltus J. , Wagner Cordula , Bijnen A. Bart
Published: October 2010

Rationale, aims and objectives  Incident reporting can contribute to safer health care. Since the rate of reporting by residents is low, it is useful to investigate which barriers exist and how these can be solved.

Methods  Data were collected in a large teaching hospital in the Netherlands. The hospital uses a confidential, voluntary and web‐based incident reporting system. Residents working in the hospital participated in focus group discussions to explore barriers and possible solutions. A grounded theory approach was used to analyse the transcribed discussions.

Results  In each focus group six to eight residents participated, resulting in a total number of 22 participants. After three focus group discussions, information saturation had been reached. Residents do not report all incidents because of a negative attitude towards incident reporting, because they experience a non‐stimulating culture and because of a lack of perceived ability to report. Residents suggest several solutions to solve the barriers: providing the possibility to report anonymously, providing feedback, creating an incident reporting culture, simplifying the procedure, clarifying what and how to report, and exciting residents to report.

Conclusions  Residents have useful suggestions to resolve the barriers that prevent them from reporting incidents. They include solutions that influence attitude, culture and perceived ability. These suggestions should be considered when making an effort to improve incident reporting by residents.
Habitat distribution influences dispersal and fine‐scale genetic population structure of eastern foxsnakes (Mintonius gloydi) across a fragmented landscape
Authors: ROW JEFFREY R. , BLOUIN‐DEMERS GABRIEL , LOUGHEED STEPHEN C.
Published: October 2010

Dispersal is a fundamental attribute of species in nature and shapes population dynamics, evolutionary trajectories and genetic variation across spatial and temporal scales. It is increasingly clear that landscape features have large impacts on dispersal patterns. Thus, understanding how individuals and species move through landscapes is essential for predicting impacts of landscape alterations. Information on dispersal patterns, however, is lacking for many taxa, particularly reptiles. Eastern foxsnakes (Mintoinus gloydi) are marsh and prairie specialists that avoid agricultural fields, but they have persisted across a fragmented region in southwestern Ontario and northern Ohio. Here, we combined habitat suitability modelling with population genetic analyses to infer how foxsnakes disperse through a habitat mosaic of natural and altered landscape features. Boundary regions between the eight genetic clusters, identified through assignment tests, were comprised of low suitability habitat (e.g. agricultural fields). Island populations were grouped into a single genetic cluster, and comparatively low FST values between island and mainland populations suggest open water presents less of a barrier than nonsuitable terrestrial habitat. Isolation by resistance and least‐cost path analysis produced similar results with matrices of pairwise individual genetic distance significantly more correlated to matrices of resistance values derived from habitat suitability than models with an undifferentiated landscape. Spatial autocorrelation results matched better with assignment results when incorporating resistance values rather than straight‐line distances. All analyses used in our study produced similar results suggesting that habitat degradation limits dispersal for foxsnakes, which has had a strong effect on the genetic population structure across this region.
Patterns of introduction and adaptation during the invasion of Aegilops triuncialis (Poaceae) into Californian serpentine soils
Authors: MEIMBERG HARALD , MILAN NEIL F. , KARATASSIOU MARIA , ESPELAND ERIN K. , McKAY JOHN K. , RICE KEVIN J.
Published: October 2010

Multiple introductions can play a prominent role in explaining the success of biological invasions. One often cited mechanism is that multiple introductions of invasive species prevent genetic bottlenecks by parallel introductions of several distinct genotypes that, in turn, provide heritable variation necessary for local adaptation. Here, we show that the invasion of Aegilops triuncialis into California, USA, involved multiple introductions that may have facilitated invasion into serpentine habitats. Using microsatellite markers, we compared the polymorphism and genetic structure of populations of Ae. triuncialis invading serpentine soils in California to that of accessions from its native range. In a glasshouse study, we also compared phenotypic variation in phenological and fitness traits between invasive and native populations grown on loam soil and under serpentine edaphic conditions. Molecular analysis of invasive populations revealed that Californian populations cluster into three independent introductions (i.e. invasive lineages). Our glasshouse common garden experiment found that all Californian populations exhibited higher fitness under serpentine conditions. However, the three invasive lineages appear to represent independent pathways of adaptation to serpentine soil. Our results suggest that the rapid invasion of serpentine habitats in California may have been facilitated by the existence of colonizing Eurasian genotypes pre‐adapted to serpentine soils.
Bacterial inflorescence rot of grapevine caused by Pseudomonas syringae pv. syringae
Authors: Whitelaw‐Weckert M. A. , Whitelaw E. S. , Rogiers S. Y. , Quirk L. , Clark A. C. , Huang C. X.
Published: October 2010

Molecular sequencing (rpoB) and standard pathological and microbiological methods identified Pseudomonas syringae pv. syringae (Pss) as the causal agent of bacterial inflorescence rot of grapevines (Vitis vinifera) in three vineyards in Tumbarumba, NSW, Australia in 2006 and 2007. Pss strains from shrivelled berries and necrotic inflorescences of diseased grapevines were used to inoculate leaves and inflorescences of potted cv. Semillon grapevines. Pss caused disease symptoms similar to those experienced in the field, including angular leaf lesions, longitudinal lesions in shoot tissues and rotting of inflorescences from before flowering until shortly after fruit set. High humidity promoted symptom severity. The necrotic bunch stem and leaf lesions were susceptible to the development of Botrytis cinerea infections. Cryo‐scanning electron microscopy (cryoSEM) indicated that Pss entered leaves and inflorescence tissues via distorted, open, raised stomata surrounded by folds of tissue that appeared as ‘star‐shaped’ callose‐rich complexes when viewed by UV light microscopy. In necrotic tissues, cryoSEM revealed Pss within petiole parenchyma cells and air‐filled rachis xylem vessels. This is the first report of inflorescence and hence fruit loss caused by Pss in grapevines. The disease is described as ‘bacterial inflorescence rot’ and regarded as one that expands the previously reported pathology of grapevines caused by P. syringae. This study also indicated that infection by Pss might promote destructive B. cinerea infections when the fungus is already present but latent, although further experimentation is needed to prove such an interaction.
Kidney from uncontrolled donors after cardiac death with one hour warm ischemic time: resuscitation by extracorporal normothermic abdominal perfusion “in situ” by leukocytes‐free oxygenated blood
Authors: Reznik Oleg , Skvortsov Andrej , Loginov Igor , Ananyev Alexey , Bagnenko Sergey , Moysyuk Yan
Published: October 2010

Reznik O, Skvortsov A, Loginov I, Ananyev A, Bagnenko S, Moysyuk Y. Kidney from uncontrolled donors after cardiac death with one hour warm ischemic time: resuscitation by extracorporal normothermic abdominal perfusion “in situ” by leukocytes‐free oxygenated blood. Clin Transplant 2011: 25: 511–516. © 2010 John Wiley & Sons A/S.

Abstract:  The availability of brain death donors is restricted by many factors. Use of uncontrolled donors after cardiac death could be a promising perspective, but the limiting factor in uncontrolled donation after cardiac death is the warm ischemic time. The purpose of our work was to develop an in situ kidney preservation protocol with application of the extracorporal normothermic abdominal perfusion for organ resuscitation in uncontrolled donors after cardiac death. The main attention was paid to the elimination of leukocytes as the key damaging factor from modified donor oxygenated blood circulating in the device. In 2009, we had 10 uncontrolled donors with warm ischemic time from 45 to 92 min; a normothermic extracorporal perfusion device was applied, providing preservation and restoration of kidney after ischemic damage. In 6 out of 20 kidney recipients, graft function was recovered immediately. All kidney grafts are functioning, and to the end of the third month, the average creatinine was 118.5 ± 19.9 mM. Treatment of ischemically damaged kidney by normothermic extracorporal perfusion with leukocyte depletion before procurement seems to be a challenging protocol for expanding donors’ pool and demands further study.
Inhibition of the renal renin‐angiotensin system and renoprotection by pitavastatin in type 1 diabetes
Authors: Toba Hiroe , Mitani Takuya , Takahashi Tamotsu , Imai Nobuyoshi , Serizawa Ryoko , Wang Jiahong , Kobara Miyuki , Nakata Tetsuo
Published: October 2010

1. The aim of the present study was to investigate whether or not pitavastatin ameliorates diabetic nephropathy and if inhibition of the rennin–angiotensin–aldosterone system (RAAS) is associated with any renoprotective effects. Pitavastatin (10 mg/ kg/day) and/or spironolactone (100 mg/kg/day) were given by gavage for 3 weeks to uninephrectomized rats with streptozotocin‐induced diabetes.

2. Pitavastatin or spironolactone significantly reduced proteinuria and collagen deposition, and normalized creatinine clearance, serum creatinine levels and blood urea nitrogen concentrations.

3. Reverse transcription polymerase chain reaction analysis showed that the renal expression of collagen I, transforming growth factor‐β and monocyte chemoattractant‐1 were increased in diabetic rats and reduced by the pitavastatin and/or spironolactone treatment.

4. These agents also decreased angiotensin converting enzyme expression and aldosterone concentrations in the renal homogenate, but had no effect on blood glucose, haemoglobinA1c, and plasma total cholesterol, Na+, K+, aldosterone and NOx levels, or on systolic blood pressure measured by the tail‐cuff method. Interestingly, cotreatment with pitavastatin and spironolactone did not result in additional normalization.

5. These results suggest that pitavastatin shows renoprotective effects against diabetic nephropathy mediated in part by inhibition of the renal RAAS, including the suppression of angiotensin‐converting enzyme expression and aldosterone production.
Mechanical ventilation in the newborn; a simplified approach Part 2: High‐frequency ventilation
Authors: Muhlethaler Vincent , Malcolm Girvan
Published: October 2010

High frequency oscillatory ventilation (HFOV) is becoming an increasingly popular intervention in the neonatal intensive care unit. This article will attempt to explain the principles of HFOV. It is inherently more difficult to become skilled in this technique than in other forms of mechanical ventilation, so caution is warranted.
Recommendations for bariatric surgery in adolescents in Australia and New Zealand
Authors: Baur Louise A , Fitzgerald Dominic A
Published: October 2010

The prevalence of severe obesity and associated co‐morbidities is increasing in adolescence. Although support for long‐term whole‐of‐family lifestyle change is the mainstay of paediatric obesity treatment, there is increasing recognition of the place of other therapies, including bariatric surgery, in the management of severely obese adolescents. While there are rising numbers of reports of bariatric surgery in adolescents, there are as yet no Australian or New Zealand recommendations available to guide decisions as to which adolescents should receive such surgery and how they should best be managed. This paper presents a summary of the recommendations that are contained within the full position paper developed on behalf of the Royal Australasian College of Physicians Paediatric Policy and Advocacy Committee Working Party on Bariatric Surgery for Adolescents, working in conjunction with the Australia and New Zealand Association of Paediatric Surgeons and the Obesity Surgery Society of Australia and New Zealand.
Changing trends in newborn sepsis in Sagamu, Nigeria: Bacterial aetiology, risk factors and antibiotic susceptibility
Authors: Ogunlesi Tinuade A , Ogunfowora Olusoga B , Osinupebi Olubunmi , Olanrewaju Durotoye M
Published: October 2010

Aim:  Sepsis is a major contributor to newborn deaths in the developing world. The objective is to determine the prevalence of newborn sepsis, the bacterial pathogens and antibiotic sensitivity pattern of the isolates.

Method:  A study of consecutive babies hospitalised in Sagamu, Nigeria, with risk factors for or clinical features of sepsis was retrospectively done between January 2006 and December 2007, and prospectively between January and December 2008. Positive blood culture defined neonatal sepsis, and the antibiotic sensitivity pattern of the organisms was also determined.

Results:  There were 1050 admissions, and 174 (16.5%) babies had positive blood culture. Of the 527 babies with risk factors and clinical features of sepsis, 174 (33.3%) had confirmed sepsis: 119 (22.5%) had early‐onset sepsis, while 55 (10.4%) had late‐onset sepsis. The incidence of neonatal sepsis in the hospital was 51.3/1000 live births. Weight less than 1.5 kg, prolonged labour, prolonged rupture of membranes and lower socio‐economic status were risk factors for sepsis. Staphylococcus aureus (31.0%), Klebsiella (23.0%), and coagulase‐negative Staphylococcus (12.6%) and Escherichia coli (11.0%) were the leading aetiologies. The isolates were most sensitive to levofloxacin (95.7%), ofloxacin (95.1%), cefotaxime (86.7%) and ceftazidime (81.3%). Their sensitivity was 56.4% to cefuroxime and gentamicin, which are commonly used.

Conclusion:  The prevalence of sepsis was high in this cohort of high‐risk infants. The low in vitro sensitivity of the leading microbes to commonly used drugs is challenging. Guidelines on the reduction of emergence of drug resistance must be provided and instituted in newborn units.