bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surveillance of Antibiotic Susceptibility Patterns among
Shigella sonnei
Strains Isolated in Belgium during the 18-Year Period 1990 to 2007
Authors: Vrints M. , Mairiaux E. , Van Meervenne E. , Collard J.-M. , Bertrand S. 
Published: March 2009

ABSTRACT

This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of
Shigella sonnei
, the predominant species causing shigellosis in Belgium. Between 1990 and 2007, a total of 7,307 strains, mainly (98.2%) isolated from stools, were diagnosed by peripheral laboratories before being confirmed as
Shigella
strains by serotyping by the National Reference Center of
Salmonella
and
Shigella
. A significant increase in resistances to tetracycline, streptomycin, trimethoprim, sulfonamides, and cotrimoxazole (i.e., trimethoprim in combination with sulfonamides) was observed during this period. Since 1998, resistance to nalidixic acid also increased to reach a peak (12.8%) of resistant isolates in 2004. Concomitantly, multidrug resistance (MDR) in this species emerged in 2007, with 82% of total isolates being MDR. However, during this 18-year period, all isolates remained fully susceptible to ciprofloxacin and gentamicin. The work includes the molecular characterization of mechanisms of resistance to ampicillin, tetracycline, chloramphenicol, and cotrimoxazole and class 1 and class 2 integrons.
S. sonnei
acquired antimicrobial resistance to traditional antibiotics (ampicillin and tetracycline) by horizontal gene transfer, while the genetic stability of transposons was responsible for a high (89%) proportion of resistance to a commonly prescribed antibiotic (cotrimoxazole). Therefore, cotrimoxazole should no longer be considered appropriate as empirical therapy for treatment of shigellosis in Belgium when antibiotics are indicated. Rates of resistance to nalidixic acid should also be attentively monitored to detect any shift in fluoroquinolone resistance, because it represents the first line among antibiotics used in the treatment of shigellosis.
Widespread Phosphorylation of Histone H2AX by Species C Adenovirus Infection Requires Viral DNA Replication
Authors: Nichols Gena J. , Schaack Jerome , Ornelles David A. 
Published: March 2009

ABSTRACT
Adenovirus infection activates cellular DNA damage response and repair pathways. Viral proteins that are synthesized before viral DNA replication prevent recognition of viral genomes as a substrate for DNA repair by targeting members of the sensor complex composed of Mre11/Rad50/NBS1 for degradation and relocalization, as well as targeting the effector protein DNA ligase IV. Despite inactivation of these cellular sensor and effector proteins, infection results in high levels of histone 2AX phosphorylation, or γH2AX. Although phosphorylated H2AX is a characteristic marker of double-stranded DNA breaks, this modification was widely distributed throughout the nucleus of infected cells and was coincident with the bulk of cellular DNA. H2AX phosphorylation occurred after the onset of viral DNA replication and after the degradation of Mre11. Experiments with inhibitors of the serine-threonine kinases ataxia telangiectasia mutated (ATM), AT- and Rad3-related (ATR), and DNA protein kinase (DNA-PK), the kinases responsible for H2AX phosphorylation, indicate that H2AX may be phosphorylated by ATR during a wild-type adenovirus infection, with some contribution from ATM and DNA-PK. Viral DNA replication appears to be the stimulus for this phosphorylation event, since infection with a nonreplicating virus did not elicit phosphorylation of H2AX. Infected cells also responded to high levels of input viral DNA by localized phosphorylation of H2AX. These results are consistent with a model in which adenovirus-infected cells sense and respond to both incoming viral DNA and viral DNA replication.
Effect of Ribavirin on the Mutation Rate and Spectrum of Hepatitis C Virus In Vivo
Authors: Cuevas José M. , González-Candelas Fernando , Moya Andrés , Sanjuán Rafael 
Published: March 2009

ABSTRACTTheir extremely error-prone replication makes RNA viruses targets for lethal mutagenesis. In the case of hepatitis C virus (HCV), the standard treatment includes ribavirin, a base analog with an in vitro mutagenic effect, but the in vivo mode of action of ribavirin remains poorly understood. Here, we test the mutagenic effects of ribavirin plus interferon treatment in vivo using a new method to estimate mutation rates based on the analysis of nonsense mutations. We apply this methodology to a large HCV sequence database containing over 15,000 reverse transcription-PCR molecular clone sequences from 74 patients infected with HCV. We obtained an estimate of the spontaneous mutation rate of ca. 10−4substitutions per site or lower, a value within the typically accepted range for RNA viruses. A roughly threefold increase in mutation rate and a significant shift in mutation spectrum were observed in samples from patients undergoing 6 months of interferon plus ribavirin treatment. This result is consistent with the known in vitro mutagenic effect of ribavirin and suggests that the antiviral effect of ribavirin plus interferon treatment is at least partly exerted through lethal mutagenesis.
Arginine Methylation of the ICP27 RGG Box Regulates ICP27 Export and Is Required for Efficient Herpes Simplex Virus 1 Replication
Authors: Souki Stuart K. , Gershon Paul D. , Sandri-Goldin Rozanne M. 
Published: March 2009

ABSTRACT
The herpes simplex virus 1 (HSV-1) multifunctional regulatory protein ICP27 shuttles between the nucleus and cytoplasm in its role as a viral mRNA export factor. Arginine methylation on glycine- and arginine-rich motifs has been shown to regulate protein export. ICP27 contains an RGG box and has been shown to be methylated during viral infection. We found by mass spectrometric analysis that three arginine residues within the RGG box were methylated. Viral mutants with substitutions of lysine for arginine residues were created as single, double, and triple mutants. Growth of these mutants was impaired and the viral replication cycle was delayed compared to wild-type HSV-1. Most striking was the finding that under conditions of hypomethylation resulting from infection with arginine substitution mutants or treatment of wild-type HSV-1-infected cells with the methylation inhibitor adenosine dialdehyde, ICP27 export to the cytoplasm occurred earlier and was more rapid than wild-type ICP27 export. We conclude that arginine methylation of the ICP27 RGG box regulates its export activity and that early export of ICP27 interferes with the performance of its nuclear functions.
Efficient Reverse Genetics Generation of Infectious Junin Viruses Differing in Glycoprotein Processing
Authors: Albariño César G. , Bergeron Éric , Erickson Bobbie Rae , Khristova Marina L. , Rollin Pierre E. , Nichol Stuart T. 
Published: March 2009

ABSTRACT
The New World arenaviruses, Junin, Machupo, Guanarito, Sabia, and Chapare, are associated with rapidly progressing severe hemorrhagic fever with a high rate of case fatality in various regions of South America. The threat of natural or deliberate outbreaks associated with these viruses makes the development of preventive or therapeutic measures important. Here we describe a Junin virus functional minigenome system and a reverse genetics system for production of infectious Junin virus. This robust, highly efficient system involves transfection of cells with only two plasmids which transcribe the virus S and L antigenomic RNAs. The utility of the system is demonstrated by generating Junin viruses which encode a glycoprotein precursor (GPC) containing the following: (i) the wild-type (SKI-1/S1P peptidase) cleavage site, (ii) no cleavage site, or (iii) a cleavage site where the SKI-1/S1P motif (RSLK) is replaced by a furin cleavage site (RRKR). In contrast to the wild-type virus, Junin virus lacking a GPC cleavage site replicated within successfully transfected cells but failed to yield infectious virus particles. This confirms observations with other arenaviruses suggesting that GPC cleavage is essential for arenavirus infectivity. In contrast, infectious Junin virus which encoded GPC cleaved by furin-like proteases was easily generated. The two-plasmid, high efficiency aspects of this Junin virus reverse genetics system show great promise for addressing important questions regarding arenavirus hemorrhagic fever disease and for development of precisely attenuated live arenavirus vaccines.
Influenza A Virus Lacking M2 Protein as a Live Attenuated Vaccine
Authors: Watanabe Shinji , Watanabe Tokiko , Kawaoka Yoshihiro 
Published: March 2009

ABSTRACT
Mutant influenza virus that lacks the transmembrane and cytoplasmic tail domains of M2 (M2 knockout [M2KO]) is attenuated in both cell culture and mice. Here, we examined the potency of M2KO influenza virus as a live attenuated influenza vaccine. M2KO virus grew as efficiently as the wild-type virus in cells stably expressing the wild-type M2, indicating the feasibility of efficient vaccine production. Mice intranasally vaccinated with M2KO virus developed protective immune responses and survived a lethal challenge with the wild-type virus, suggesting that the M2KO virus has potential as a live attenuated vaccine.
Characterization of the Interaction between Latency-Associated Nuclear Antigen and Glycogen Synthase Kinase 3β
Authors: Hagen Thilo 
Published: March 2009

ABSTRACT
The latency-associated nuclear antigen (LANA) of Karposi's sarcoma-associated herpesvirus has been reported to interact with glycogen synthase kinase 3β (GSK-3β) and regulate its activity, leading to inhibition of GSK-3-dependent β-catenin degradation. In this study, the interaction between LANA and GSK-3β was characterized further. LANA was found to interact with GSK-3β in vitro as well as in intact cells. However, LANA did not regulate GSK-3β kinase activity and LANA-induced upregulation of β-catenin was GSK-3β independent. LANA did not regulate the stability of β-catenin or of its reported interaction partners p53 and von Hippel-Lindau protein. Additional targets of LANA are likely to mediate its malignancy-promoting function.
MODELING THE POPULATION DYNAMICS OF ANTIBIOTIC-RESISTANT BACTERIA: AN AGENT-BASED APPROACH
Authors: MURPHY JAMES T. , WALSHE RAY , DEVOCELLE MARC 
Published: March 2009

The response of bacterial populations to antibiotic treatment is often a function of a diverse range of interacting factors. In order to develop strategies to minimize the spread of antibiotic resistance in pathogenic bacteria, a sound theoretical understanding of the systems of interactions taking place within a colony must be developed. The agent-based approach to modeling bacterial populations is a useful tool for relating data obtained at the molecular and cellular level with the overall population dynamics. Here we demonstrate an agent-based model, called Micro-Gen, which has been developed to simulate the growth and development of bacterial colonies in culture. The model also incorporates biochemical rules and parameters describing the kinetic interactions of bacterial cells with antibiotic molecules.Simulations were carried out to replicate the development of methicillin-resistant S. aureus (MRSA) colonies growing in the presence of antibiotics. The model was explored to see how the properties of the system emerge from the interactions of the individual bacterial agents in order to achieve a better mechanistic understanding of the population dynamics taking place. Micro-Gen provides a good theoretical framework for investigating the effects of local environmental conditions and cellular properties on the response of bacterial populations to antibiotic exposure in the context of a simulated environment.
Carbon Dioxide Emissions of the City Center of Firenze, Italy: Measurement, Evaluation, and Source Partitioning
Authors: Matese A. , Gioli B. , Vaccari F. P. , Zaldei A. , Miglietta F. 
Published: March 2009

AbstractAn eddy covariance station was installed in the city center of Firenze, Italy, to measure carbon fluxes at half-hourly intervals over a mostly homogeneous urban area. Carbon dioxide (CO2) emission observations made over an initial period of 3.5 months were compared with indirect estimates of CO2 emissions based on inventory data sources of vehicle circulation and natural gas consumption for domestic heating and cooking. Such a comparison provided proper evaluation of the measurements. Using seasonal dynamics of observed fluxes, the overall CO2 source of the city center was partitioned into its major components (i.e., road traffic and domestic heating). Results were directly compared with CO2 source estimates based on inventory sources.
Orographic Precipitation in the Tropics: Large-Eddy Simulations and Theory
Authors: Kirshbaum Daniel J. , Smith Ronald B. 
Published: March 2009

AbstractRecent radar and rain gauge observations from the Caribbean island of Dominica (15°N) show a strong orographic enhancement of trade wind precipitation. The mechanisms behind this enhancement are investigated using idealized large-eddy simulations with a realistic representation of the shallow trade wind cumuli over the open ocean upstream of the island. The dominant mechanism is found to be the rapid growth of convection by the bulk lifting of the inhomogenous impinging flow. When rapidly lifted by the terrain, existing clouds and other moist parcels gain buoyancy relative to rising dry air because of their different adiabatic lapse rates. The resulting energetic, closely packed convection forms precipitation readily and brings frequent heavy showers to the high terrain. Despite this strong precipitation enhancement, only a small fraction (1%) of the impinging moisture flux is lost over the island. However, an extensive rain shadow forms to the lee of Dominica due to the convective stabilization, forced descent, and wave breaking. A linear model is developed to explain the convective enhancement over the steep terrain.
Relation between Indian Monsoon Variability and SST
Authors: Krishnamurthy V. , Kirtman Ben P. 
Published: March 2009

AbstractThe relation between the intraseasonal modes of the South Asian monsoon and the sea surface temperature (SST) in the tropical oceans on a daily time scale has been investigated. Long lead–lag relations of the daily SST anomalies with the dominant monsoon modes obtained from a multichannel singular spectrum analysis (MSSA) of the daily outgoing longwave radiation (OLR) over the South Asian monsoon region are presented. The dominant MSSA monsoon modes, consisting of two oscillatory modes (at 45- and 28-day time scales) and two seasonally persistent modes, are found to have varying degrees of lead–lag relation with the SSTs in the Indian and Pacific Oceans. While the 45-day oscillatory mode has weak correlations with the SSTs in the Pacific and Indian Ocean, it also reveals a possible 45-day oscillation in the SST in the northwestern Pacific and northern Indian Ocean. The 28-day oscillatory mode has negligible correlation with the tropical SST. One of the persistent monsoon modes has a very strong relation with the El Niño–Southern Oscillation (ENSO)–related SST in the Pacific with correlation above 0.8 for a long lead–lag time range. The other persistent monsoon mode has moderate lead–lag correlation with the Indian Ocean dipole (IOD) SST as well as with the ENSO-like SST in the Pacific. The strong relation of the persistent modes, which mainly determine the seasonal mean monsoon, when the SST leads, provides hope for long-term prediction of the seasonal mean monsoon. The strong relation between the monsoon and the SST, when the monsoon leads, points toward the strong influence of the monsoon on the variability of ENSO and IOD.
Who's Minding the Gate?
Authors: Bock Mary Angela 
Published: March 2009

Camera pools and video feed systems allow news institutions to receive video imagery with greater efficiency and lower costs. Such arrangements are frequently managed and negotiated through politically engaged institutions. The resulting video is transmitted and traded with the underlying assumption that images are discrete, objective representations of real events, an assumption that is called into question when the practice is carefully examined. Unlike facts or ideas, which are intangible and constructed entirely in language, video images are constructed both discursively and materially. Consequently the power to grant physical access to events for photographic coverage grants political actors an advantage as they negotiate their image, literally and metaphorically. This qualitative study describes several such feeds and politically regulated video subsidies, their use by news organizations, and the means by which political agents influence their own image through such feeds. Data in the form of extended interviews and field observations were collected between 2005 and 2007 in the United States and Britain. Site visits include Congress, a U.S. statehouse, a state cable operation, and British Parliament. The findings indicate that journalism's relay of video images as objective, factual material, rather than constructions negotiated with political actors, fosters an illusion of transparency.
Humanized large-scale expanded endothelial colony–forming cells function in vitro and in vivo
Authors: Reinisch Andreas , Hofmann Nicole A. , Obenauf Anna C. , Kashofer Karl , Rohde Eva , Schallmoser Katharina , Flicker Karin , Lanzer Gerhard , Linkesch Werner , Speicher Michael R. , Strunk Dirk 
Published: March 2009

Abstract
Endothelial progenitor cells are critically involved in essential biologic processes, such as vascular homeostasis, regeneration, and tumor angiogenesis. Endothelial colony–forming cells (ECFCs) are endothelial progenitor cells with robust proliferative potential. Their profound vessel-forming capacity makes them a promising tool for innovative experimental, diagnostic, and therapeutic strategies. Efficient and safe methods for their isolation and expansion are presently lacking. Based on the previously established efficacy of animal serum–free large-scale clinical-grade propagation of mesenchymal stromal cells, we hypothesized that endothelial lineage cells may also be propagated efficiently following a comparable strategy. Here we demonstrate that human ECFCs can be recovered directly from unmanipulated whole blood. A novel large-scale animal protein-free humanized expansion strategy preserves the progenitor hierarchy with sustained proliferation potential of more than 30 population doublings. By applying large-scale propagated ECFCs in various test systems, we observed vascular networks in vitro and perfused vessels in vivo. After large-scale expansion and cryopreservation phenotype, function, proliferation, and genomic stability were maintained. For the first time, proliferative, functional, and storable ECFCs propagated under humanized conditions can be explored in terms of their therapeutic applicability and risk profile.
The response of mental health professionals to clients seeking help to change or redirect same-sex sexual orientation
Authors: Bartlett Annie , Smith Glenn , King Michael 
Published: March 2009

Abstract

Background
we know very little about mental health practitioners' views on treatments to change sexual orientation. Our aim was to survey a representative sample of professional members of the main United Kingdom psychotherapy and psychiatric organisations about their views and practices concerning such treatments.

Methods
We sent postal questions to mental health professionals who were members of British Psychological Society, the British Association for Counselling and Psychotherapy, the United Kingdom Council for Psychotherapy and the Royal College of Psychiatrists. Participants were asked to give their views about treatments to change homosexual desires and describe up to five patients each, whom they has treated in this way.

Results
Of 1848 practitioners contacted, 1406 questionnaires were returned and 1328 could be analysed. Although only 55 (4%) of therapists reported that they would attempt to change a client's sexual orientation if one consulted asking for such therapy, 222 (17%) reported having assisted at least one client/patient to reduce or change his or her homosexual or lesbian feelings. 413 patients were described by these 222 therapists: 213 (52%) were seen in private practice and 117 (28%) were not followed up beyond the period of treatment. Counselling was the commonest (66%) treatment offered and there was no sign of a decline in treatments in recent years. 159 (72%) of the 222 therapists who had provided such treatment considered that a service should be available for people who want to change their sexual orientation. Client/patient distress and client/patient autonomy were seen as reasons for intervention; therapists paid attention to religious, cultural and moral values causing internal conflict.

Conclusion
A significant minority of mental health professionals are attempting to help lesbian, gay and bisexual clients to become heterosexual. Given lack of evidence for the efficacy of such treatments, this is likely to be unwise or even harmful.
Practical and reliable FRET/FLIM pair of fluorescent proteins
Authors: Shcherbo Dmitry , Souslova Ekaterina A , Goedhart Joachim , Chepurnykh Tatyana V , Gaintzeva Anna , Shemiakina Irina I , Gadella Theodorus WJ , Lukyanov Sergey , Chudakov Dmitriy M 
Published: March 2009

Abstract

Background
In spite of a great number of monomeric fluorescent proteins developed in the recent years, the reported fluorescent protein-based FRET pairs are still characterized by a number of disadvantageous features, complicating their use as reporters in cell biology and for high-throughput cell-based screenings.

Results
Here we screened some of the recently developed monomeric protein pairs to find the optimal combination, which would provide high dynamic range FRET changes, along with high pH- and photo-stability, fast maturation and bright fluorescence, and reliable detection in any fluorescent imaging system. Among generated FRET pairs, we have selected TagGFP-TagRFP, combining all the mentioned desirable characteristics. On the basis of this highly efficient FRET pair, we have generated a bright, high contrast, pH- and photo-stable apoptosis reporter, named CaspeR3 (Caspase 3 Reporter).

Conclusion
The combined advantages suggest that the TagGFP-TagRFP is one of the most efficient green/red couples available to date for FRET/FLIM analyses to monitor interaction of proteins of interest in living cells and to generate FRET-based sensors for various applications. CaspeR3 provides reliable detection of apoptosis, and should become a popular tool both for cell biology studies and high throughput screening assays.
Observation of Austenitic Grain Growth in Some Alloy Structural Steels
Authors: Gerosa Riccardo , Rivolta Barbara , Silva Giuseppe , Demarchi Renato , Poli Andrea 
Published: March 2009

Abstract
In order to satisfy the demands coming from the thermal and thermo-chemical treatments, higher treatment temperature values are required to shorten the soaking time or to increase the structurally modified thickness, or both. Toughness and mechanical strength of a steel are strictly related to the presence of small grain dimension microstructure, which can be obtained through the presence of precipitates at the grain boundaries. The refinement of the microstructure is connected to the chemical composition and dimension of the precipitates, which dissolve partially or totally above a critical temperature. In this paper, two steels for mechanical application have been studied. In the supply conditions these steels are characterized by a precipitation condition due to the thermal treatment carried out in the steelmaker plant. By metallographic techniques, the grain growth has been studied, varying temperature and soaking time during thermal treatments. The dilatometric tests have been useful to follow the transformations able to contain the increase of the austenitic grain size and TEM analysis has contributed to confirm the nature of these transformations.