bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exogenous 5,6‐dimethylbenzimidazole caused production of a non‐functional tetrachloroethene reductive dehalogenase in Sulfurospirillum multivorans
Authors: Keller Sebastian , Ruetz Markus , Kunze Cindy , Kräutler Bernhard , Diekert Gabriele , Schubert Torsten 
Published: September 2013

SummaryCorrinoid‐dependent reductive dehalogenation is mediated by phylogenetically diverse anaerobic bacteria that either synthesize corrinoids de novo or are dependent on corrinoid salvaging from the environment. The tetrachloroethene (PCE) reductive dehalogenase (PceA) of the Gram‐negative Epsilonproteobacterium Sulfurospirillum multivorans harbours a norpseudo‐B12 as corrinoid cofactor. Norpseudo‐B12 differs from coenzyme B12 in the nucleotide loop structure. Adenine instead of 5,6‐dimethylbenzimidazole (DMB) serves as lower ligand base of the central cobalt ion, and the nucleotide loop of norpseudo‐B12 lacks a methyl group at position 176. In this study, S. multivorans was grown anaerobically with PCE in the presence of DMB. At a DMB concentration of 25 μM, the adenine moiety in the nucleotide loop of norpseudo‐B12 was quantitatively replaced by DMB. The formation of the DMB‐containing nor‐B12 severely affected PCE‐dependent growth and the PceA activity. In DMB‐treated cells processing of the cytoplasmic PceA precursor was impeded, a result pointing to retarded cofactor incorporation. PceA enriched from cells cultivated with DMB contained nor‐B12. Nor‐B12 purified from cells grown in the presence of DMB mediated the abiotic reductive dehalogenation of trichloroacetate to dichloroacetate at a 25‐fold lower rate in comparison with norpseudo‐B12, a fact underpinning the relevance of norpseudo‐B12 as efficient catalyst for reductive dehalogenation in general.
The logic of metabolism and its fuzzy consequences
Authors: Danchin Antoine , Sekowska Agnieszka 
Published: September 2013

SummaryIntermediary metabolism molecules are orchestrated into logical pathways stemming from history (L‐amino acids, d‐sugars) and dynamic constraints (hydrolysis of pyrophosphate or amide groups is the driving force of anabolism). Beside essential metabolites, numerous variants derive from programmed or accidental changes. Broken down, variants enter standard pathways, producing further variants. Macromolecule modification alters enzyme reactions specificity. Metabolism conform thermodynamic laws, precluding strict accuracy. Hence, for each regular pathway, a wealth of variants inputs and produces metabolites that are similar to but not the exact replicas of core metabolites. As corollary, a shadow, paralogous metabolism, is associated to standard metabolism. We focus on a logic of paralogous metabolism based on diversion of the core metabolic mimics into pathways where they are modified to minimize their input in the core pathways where they create havoc. We propose that a significant proportion of paralogues of well‐characterized enzymes have evolved as the natural way to cope with paralogous metabolites. A second type of denouement uses a process where protecting/deprotecting unwanted metabolites – conceptually similar to the procedure used in the laboratory of an organic chemist – is used to enter a completely new catabolic pathway.
Surfactin triggers biofilm formation of Bacillus subtilis in melon phylloplane and contributes to the biocontrol activity
Authors: Zeriouh Houda , de Vicente Antonio , Pérez‐García Alejandro , Romero Diego 
Published: September 2013

SummaryThe biocontrol activity of many Bacillus species has been traditionally related to the direct antagonism of pathogens. In previous works, we reported that B. subtilis strain UMAF6614 was an efficient biocontrol agent that produced bacillomycin, fengycin and surfactin lipopeptides. Bacillomycins and fengycins were shown to have antagonistic activity towards fungal and bacterial pathogens of cucurbits; however, the functionality of surfactin remained unclear. In this study, the role of surfactin in the biocontrol activity of this strain was investigated. We observed that a deficiency in surfactin production led to a partial reduction of disease suppression by this biocontrol agent, which coincided with a defect in biofilm formation and the colonization of the melon phylloplane. These effects were due to a dramatic reduction in the production of exopolysaccharide and the TasA protein, which are the two major components of the extracellular matrix. We propose that the biocontrol activity of this strain is the result of the coordinated action of the three families of lipopeptides. B. subtilis UMAF6614 produces surfactin to trigger biofilm formation on melon phylloplane, which ensures the long‐term persistence and the adequate secretion of suppressive lipopeptides, bacillomycins and fengycins, which efficiently target pathogens.
NrsZ: a novel, processed, nitrogen‐dependent, small non‐coding RNA that regulates Pseudomonas aeruginosa PAO1 virulence
Authors: Wenner Nicolas , Maes Alexandre , Cotado‐Sampayo Marta , Lapouge Karine 
Published: September 2013

SummaryThe opportunistic pathogen Pseudomonas aeruginosa PAO1 has a remarkable capacity to adapt to various environments and to survive with limited nutrients. Here, we report the discovery and characterization of a novel small non‐coding RNA: NrsZ (nitrogen‐regulated sRNA). We show that under nitrogen limitation, NrsZ is induced by the NtrB/C two‐component system, an important regulator of nitrogen assimilation and P. aeruginosa's swarming motility, in concert with the alternative sigma factor RpoN. Furthermore, we demonstrate that NrsZ modulates P. aeruginosa motility by controlling the production of rhamnolipid surfactants, virulence factors notably needed for swarming motility. This regulation takes place through the post‐transcriptional control of rhlA, a gene essential for rhamnolipids synthesis. Interestingly, we also observed that NrsZ is processed in three similar short modules, and that the first short module encompassing the first 60 nucleotides is sufficient for NrsZ regulatory functions.
The Weaknesses of Civic Territorial Organizations: Civic Engagement and Homeowners Associations in Urban China
Authors: Fu Qiang , Lin Nan 
Published: September 2013

AbstractChina's massive transformation in urban governance, which is characterized by breaking the link between workplace and residence and consolidating state territorial agencies at the grassroots level, has profound implications for urban residents. While community building is employed as a deliberate (top‐down) approach to restore a governable urban society, the establishment, development and problems of bottom‐up civic territorial organizations — homeowners associations — are garnering increased attention from academia. Based on field research conducted in Guangzhou, Shenzhen and Meizhou in Guangdong Province from 2009 to 2011, we show that civic engagement, a necessary condition for the development of homeowners associations, is inadequate across urban communities. To understand why, we identified and analyzed three elements — lack of awareness of partitioned property ownership, the hidden costs of civic engagement and deficiency in social capital — as factors that impede civic engagement across urban communities. These elements also provide yardsticks for scholars to evaluate why, whether and how homeowners (dis‐)engage from neighborhood affairs.
Oligotyping: differentiating between closely related microbial taxa using 16S rRNA gene data
Authors: Eren A. Murat , Maignien Loïs , Sul Woo Jun , Murphy Leslie G. , Grim Sharon L. , Morrison Hilary G. , Sogin Mitchell L. 
Published: September 2013

Summary

Bacteria comprise the most diverse domain of life on Earth, where they occupy nearly every possible ecological niche and play key roles in biological and chemical processes. Studying the composition and ecology of bacterial ecosystems and understanding their function are of prime importance. High‐throughput sequencing technologies enable nearly comprehensive descriptions of bacterial diversity through 16S ribosomal RNA gene amplicons. Analyses of these communities generally rely upon taxonomic assignments through reference data bases or clustering approaches using de facto sequence similarity thresholds to identify operational taxonomic units. However, these methods often fail to resolve ecologically meaningful differences between closely related organisms in complex microbial data sets.

In this paper, we describe oligotyping, a novel supervised computational method that allows researchers to investigate the diversity of closely related but distinct bacterial organisms in final operational taxonomic units identified in environmental data sets through 16S ribosomal RNA gene data by the canonical approaches.

Our analysis of two data sets from two different environments demonstrates the capacity of oligotyping at discriminating distinct microbial populations of ecological importance.

Oligotyping can resolve the distribution of closely related organisms across environments and unveil previously overlooked ecological patterns for microbial communities. The URL http://oligotyping.org offers an open‐source software pipeline for oligotyping.
Genetic diversity of legume yellow mosaic begomoviruses in Indonesia and Vietnam
Authors: Tsai W.S. , Shih S.L. , Rauf A. , Safitri R. , Hidayati N. , Huyen B.T.T. , Kenyon L. 
Published: September 2013

AbstractHigh incidences of yellow mosaic symptoms were observed in soybean and yard‐long bean crops in Indonesia in 2009 and in mungbean crops in Vietnam in 2011. All five soybean and 20 yard‐long bean samples from Java, Indonesia, and 15 mungbean samples from Vietnam with symptoms tested positive for begomovirus infection by polymerase chain reaction (PCR) with primer pair PAL1v1978B/PAR1c715H. On the basis of collection location and the nucleotide sequence comparisons of the 1.5 kb begomoviral DNA‐A components amplified, a subset of samples comprising two soybean and six yard‐long bean isolates from Indonesia and five mungbean isolates from Vietnam were taken forward for more detailed examination. Sequence comparison and phylogenetic analysis of the full‐length sequences of all Indonesian and Vietnam isolates alongside other legume‐infecting begomoviruses revealed that all the isolates from Indonesia were Mungbean yellow mosaic India virus (MYMIV) strain‐A, and all from Vietnam were Mungbean yellow mosaic virus (MYMV) strain‐B. To the best of our knowledge, this is the first identification of MYMIV and MYMV associated with yellow mosaic of legumes in Indonesia and Vietnam, respectively. The epidemiological implications and potential consequences of the emergence of legume‐infecting begomoviruses on legume production in these areas of Southeast Asia are discussed.
Seed yield, head characteristics and oil content in sunflower varieties as influenced by seeds from single and multiple headed plants under humid tropical conditions
Authors: Olowe V.I. , Folarin O.M. , Adeniregun O.O. , Atayese M.O. , Adekunle Y.A. 
Published: September 2013

AbstractField trials were conducted during 2004 and 2005 to determine the effect of sowing seeds from plants with multiple heads and seeds from single headed plants of sunflower on seed yield, head characteristics and oil content of three widely grown open pollinated varieties (Funtua, Record and Isaanka) in the humid forest—savanna transition zone which is outside the current growing areas with a view to improving stability and sunflower productivity in this region. Seeds from multiple headed plants produced plants that flowered and matured 2–3 days later than plants from single headed plants. Apart from days to flowering in 2004, number of days to maturity and plant height were affected independently by variety and seed source factors. However, the seeds from single headed plants produced plants that recorded significantly (P < 0.01) higher head weight, head diameter, achene weight and number per head than plants from seeds of plants with multiple heads. Seed source had little effect on sunflower seed yield and oil content. However, Funtua produced significantly (P < 0.05) high seed yield (1956.0 kg ha−1 ± 76.06) when seeds from plants with multiple heads were sown, while Isaanka recorded comparatively high seed yield from seeds of plants from either multiple (1221.0 kg ha−1 ± 165.90) or single heads (1388.0 kg ha−1 ± 135.84) and Record (1201.0 kg ha−1 ± 96.97) when seeds from single headed plants were sown. Therefore, it is recommended that prospective sunflower growers who wish to cultivate Isaanka, can sow seeds from either the multiple or single head and preferably the multiple head for Funtua, and single head for Record.
Pre‐hospital critical care by anaesthesiologist‐staffed pre‐hospital services in Scandinavia: a prospective population‐based study
Authors: KRÜGER A. J. , LOSSIUS H. M. , MIKKELSEN S. , KUROLA J. , CASTRÉN M. , SKOGVOLL E. 
Published: September 2013

BackgroundAll Scandinavian countries provide anaesthesiologist‐staffed pre‐hospital services. Little is known of the incidence of critical illness or injury attended by these services. We aimed to investigate anaesthesiologist‐staffed pre‐hospital services in Scandinavia with special emphasis on incidence and severity.MethodsThis population‐based, prospective study recorded activity in 16 anaesthesiologist‐staffed pre‐hospital services in Denmark, Finland, Norway and Sweden serving half of the Scandinavian population. We calculated population incidence of medical conditions, and the proportion of patients with severely deranged vital signs and/or receiving advanced therapy.ResultsFour thousand two hundred thirty‐six alarm calls were recorded during 4 weeks. Two thousand two hundred fity‐six alarms resulted in a patient encounter. The population incidence varied from 74.9 missions per 10,000 person‐years (Denmark), followed by Finland with 14.6, Norway with 11, and Sweden with 5. Medical aetiology was most frequent (14.9 missions per 10,000 person‐years, 95% CI: 14.2–15.8). Trauma was second (5.6 missions per 10,000 person‐years, 95%CI: 5.12–6.09). Twenty‐three per cent of patients had severely deranged vital functions, and advanced emergency medical procedures were performed in every four to twelve encounters (Denmark 8%, Sweden 15%, Norway 23%, and Finland 25%). The probability that the patient was physiologically deranged, received advanced medication, or procedure was 35%. Critical illness or injury occured at a rate of 25–30 per 10,000 person‐years.ConclusionsThe incidence of pre‐hospital anaesthesiologist patient encounters in Scandinavia varies. Medical aetiology is most frequent. Almost one‐quarter of patients presents with deranged vital functions requiring emergency measures. The Scandinavian pre‐hospital population incidence of critical illness and injury is 25–30 per 10,000 person‐years.
A novel mGluR5 antagonist, MFZ 10‐7, inhibits cocaine‐taking and cocaine‐seeking behavior in rats
Authors: Keck Thomas M. , Zou Mu‐Fa , Bi Guo‐Hua , Zhang Hai‐Ying , Wang Xiao‐Fei , Yang Hong‐Ju , Srivastava Ratika , Gardner Eliot L. , Xi Zheng‐Xiong , Newman Amy Hauck 
Published: September 2013

AbstractPre‐clinical studies suggest that negative allosteric modulators (NAMs) of the metabotropic glutamate receptor subtype 5 (mGluR5), including 2‐methyl‐6‐(phenylethynyl)pyridine (MPEP), 3‐[(2‐methyl‐1,3‐thiazol‐4‐yl)ethynyl]pyridine (MTEP) and fenobam are highly effective in attenuating drug‐taking and drug‐seeking behaviors. However, both MPEP and MTEP have no translational potential for use in humans because of their off‐target effects and short half‐lives. Here, we report that 3‐fluoro‐5‐[(6‐methylpyridin‐2‐yl)ethynyl]benzonitrile (MFZ 10‐7), a novel mGluR5 NAM, is more potent and selective than MPEP, MTEP and fenobam in both in vitro binding and functional assays. Similar to MTEP, intraperitoneal administration of MFZ 10‐7 inhibited intravenous cocaine self‐administration, cocaine‐induced reinstatement of drug‐seeking behavior and cocaine‐associated cue‐induced cocaine‐seeking behavior in rats. Although MFZ 10‐7 and MTEP lowered the rate of oral sucrose self‐administration, they did not alter total sucrose intake. Further, MFZ 10‐7 appeared to be more potent than MTEP in inducing downward shifts in the cocaine dose–response curve, but less effective than MTEP in attenuating sucrose‐induced reinstatement of sucrose‐seeking behavior. MFZ 10‐7 and MTEP had no effect on basal locomotor behavior. These findings not only provide additional evidence supporting an important role for mGluR5 in cocaine reward and addiction, but also introduce a new tool for both in vitro and in vivo investigations with which to further characterize this role.
Sexual selection and genital evolution
Authors: Simmons Leigh W 
Published: September 2013

AbstractMale genitalia show patterns of divergent evolution, and sexual selection is recognised as being responsible for this taxonomically widespread phenomenon. Much of the empirical support for the sexual selection hypothesis comes from studies of insects. Here, I synthesise the literature on insect genital evolution, and use this synthesis to address the debate over the mechanisms of selection most likely to explain observed patterns of macroevolutionary divergence in genital morphology. Studies of seven insect orders provide evidence that non‐intromittent genitalia are subject to sexual selection through their effects on mating success, while intromittent genitalia are subject to selection through their effects on fertilisation success. However, studies that use quantitative methods to analyse the form of selection are necessary to identify the mechanisms of sexual selection involved. Phylogenetic analyses from diverse taxonomic groups confirm that divergence in male genital morphology can be predicted from variation in the opportunity for sexual selection. Much debate revolves around the importance of female choice and sexual conflict in the evolution of male genitalia, the resolution of which lies in economic studies of mating interactions and in recognising sexual selection as a continuum between male competition, sexual conflict and female choice. The species isolating lock‐and‐key hypothesis is frequently dismissed as unimportant in genital evolution because in part of a perceived lack of variation in female genitalia across species. Increasingly, however, studies report species‐specific variation in female genital morphology and its coevolutionary divergence with male genital morphology. Contemporary views recognise a continuum between female choice that enforces species isolation and female choice that targets variation in male quality within populations, placing lock‐and‐key processes into the realm of sexual selection. Distinguishing between species‐isolating and directional forms of female choice will require studies that examine both the tempo and mode of divergence, both within and among species.
Tolerogenic CX3CR1+ B cells suppress food allergy‐induced intestinal inflammation in mice
Authors: Liu Z.‐Q. , Wu Y. , Song J.‐P. , Liu X. , Liu Z. , Zheng P.‐Y. , Yang P.‐C. 
Published: September 2013

AbstractBackgroundB lymphocytes are an important cell population of the immune regulation; their role in the regulation of food allergy has not been fully understood yet.ObjectiveThis study aims to investigate the role of a subpopulation of tolerogenic B cells (TolBC) in the generation of regulatory T cells (Treg) and in the suppression of food allergy‐induced intestinal inflammation in mice.MethodsThe intestinal mucosa‐derived CD5+ CD19+ CX3CR1+ TolBCs were characterized by flow cytometry; a mouse model of intestinal T helper (Th)2 inflammation was established to assess the immune regulatory role of this subpopulation of TolBCs.ResultsA subpopulation of CD5+ CD19+ CX3CR1+ B cells was detected in the mouse intestinal mucosa. The cells also expressed transforming growth factor (TGF)‐β and carried integrin alpha v beta 6 (αvβ6). Exposure to recombinant αvβ6 and anti‐IgM antibody induced naive B cells to differentiate into the TGF‐β‐producing TolBCs. Coculturing this subpopulation of TolBCs with Th0 cells generated CD4+ CD25+ Foxp3+ Tregs. Adoptive transfer with the TolBCs markedly suppressed the food allergy‐induced intestinal Th2 pattern inflammation in mice.ConclusionsCD5+ CD19+ CX3CR1+ TolBCs are capable of inducing Tregs in the intestine and suppress food allergy‐related Th2 pattern inflammation in mice.
Teenage pregnancies in the European Union in the context of legislation and youth sexual and reproductive health services
Authors: Part Kai , Moreau Caroline , Donati Serena , Gissler Mika , Fronteira Inês , Karro Helle ,   the REPROSTAT group
Published: September 2013

AbstractObjectiveTo study cross‐country and regional variations and trends in reported teenage pregnancies in the context of legislation and youth sexual and reproductive health (SRH) services in Europe.DesignData were collected on teenage live births and induced abortions, abortion legislation and youth SRH services.SettingPopulation‐based statistics from the European Union (EU) member states.PopulationFifteen‐ to nineteen‐year‐old female teenagers.MethodsDetailed statistical information for each member state about teenage live births, induced abortions, abortion legislation and youth SRH services were compiled relying on national and international data sources.Main outcome measuresThe annual reported pregnancies per 1000 women aged 15–19 years.ResultsTeenage pregnancy rates have declined since 2001, although progress has been uneven across regions and countries. Eastern Europe has a higher average teenage pregnancy rate (41.7/1000) than Northern (30.7/1000), Western (18.2/1000) and Southern Europe (17.6/1000). While data on teenage live births are available across Europe, data on teenage abortions are unavailable or incomplete in more than one‐third of EU countries. Reported teenage pregnancy rates are generally lower for countries where parental consent for abortion is not required, youth SRH services are available in all areas and contraceptives are subsidized for all minors, compared with countries where these conditions are not met.ConclusionsThe collection of standardized teenage pregnancy statistics is critically needed in the EU. The remarkable variability in teenage pregnancy rates across the EU is likely to be explained, among other factors, by varying access to abortion and youth SRH services.