bluuebunny/crossref_metadata_2025 huggingface dataset:
Lawyers at Mid‐Career: A 20‐Year Longitudinal Study of Job and Life Satisfaction
Authors: Monahan John , Swanson Jeffrey
Published: August 2009

This study is the first to our knowledge to simultaneously measure the predictors of lawyers' satisfaction with their careers and the predictors of lawyers' satisfaction with their lives more broadly. One class of the University of Virginia School of Law was studied between their matriculation in 1987 and their graduation in 1990. All 360 living graduates of this class were contacted in 2007, with a response rate of 72.2 percent. Descriptive information was obtained and empirically validated measures of both career satisfaction and life satisfaction were administered. Respondents were found to have taken many diverse career paths, with most (85 percent) having changed jobs at least once, and half having changed jobs at least twice. Gender differences in the personal and professional lives of respondents were pervasive. Women graduates were far more likely than men to interrupt or forego full‐time employment (39 percent vs. 1 percent), mainly in order to care for children, and were also more likely to have a spouse or partner employed full time outside the home (77 percent vs. 24 percent). Working conditions at large private law firms emerged as a significant problem for many respondents; half of those who started their careers in large firms left to go to a different type of employer. Finally, both career satisfaction and life satisfaction were found to be high, with 81 percent of the respondents satisfied with their decision to become a lawyer, and 86 percent satisfied with their lives more broadly.
How Will They Vote? Predicting the Future Behavior of Supreme Court Nominees, 1937–2006
Authors: Cameron Charles M. , Park Jee‐Kwang
Published: August 2009

Previous research suggests that the future behavior of nominees to the U.S. Supreme Court is relatively unpredictable, except for civil liberties cases. We devise a new measure of nominees' political ideology that more efficiently uses preconfirmation information about the nominees. The measure employs Segal‐Cover scores (based on content analysis of contemporary newspaper editorials) as well as DW‐NOMINATE indicators, and is scaled into the DW‐NOMINATE space. The measure predicts confirmed nominees' overall immediate, short‐term, and longer‐term voting behavior, as well as voting in issue‐specific domains, much better than do previous measures. It is particularly successful for nominees confirmed after 1957.
Discovery of 1‐[1‐(1‐Methylcyclooctyl)‐4‐piperidinyl]‐2‐[(3R)‐3‐piperidinyl]‐1H‐benzimidazole: Integrated Drug‐Design and Structure–Activity Relationships for Orally Potent, Metabolically Stable and Potential‐Risk Reduced Novel Non‐Peptide Nociceptin/Orphanin FQ Receptor Agonist as Antianxiety Drug‡
Authors: Hayashi Shigeo , Hirao Akiko , Nakamura Hiroshi , Yamamura Kenzo , Mizuno Kunihiko , Yamashita Hiroyo
Published: August 2009

Anxiety disorders, caused by continuous or acute stress or fear, have been highly prevailing psychiatric disorders. For the acute treatment of the disorders, benzodiazepines have been widely used despite having liabilities that limit their utility. Alternatively, endogenous nociceptin/orphanin FQ and nociceptin/orphanin FQ peptide receptor (or opioid‐receptor‐like‐1 receptor) have important roles in the integration of emotional components, e.g. anxiolytic activity is the key behavioral action of nociceptin/orphanin FQ in brain. In our preceding study, various structurally novel 1,2‐disubstituted benzimidazole derivatives were designed and synthesized as highly potent nociceptin/orphanin FQ peptide receptor selective full agonistsin vitrowith high or moderate nociceptin/orphanin FQ peptide receptor occupancy in the mice brainper osbased on appropriate physicochemical properties for the oral brain activity [Hayashiet al.(2009) J Med Chem;52:610–625]. In the present study, drug design and structure–activity relationships for Vogel anticonflict activities in miceper os, metabolic stabilities in human liver microsome, CYP2D6 inhibitions, serum protein bindings, and human ether‐a‐go‐go related gene binding affinities of novel nociceptin/orphanin FQ peptide receptor agonists were investigated. Through the series of coherent drug discovery studies, the strongest nociceptin/orphanin FQ peptide receptor agonist, 1‐[1‐(1‐methylcyclooctyl)‐4‐piperidinyl]‐2‐[(3R)‐3‐piperidinyl]‐1H‐benzimidazole was designed and identified as a new‐class orally potent anxiolytic with little side‐effects, as significant findings.
Discuss the factors that affect the outcome of endodontic treatment
Authors: Chandra Akhil
Published: August 2009

Factors affecting the outcome of endodontic treatment are discussed from the theoretical viewpoint (microbes, foreign bodies and epithelium) and from a clinical aspect (preoperative factors, intraoperative factors and miscellaneous factors). The following conditions favour endodontic success significantly: the absence of a periapical infection, a well‐condensed root filling, the root filling extending to 2 mm within the radiographic apex and not beyond, a satisfactory coronal restoration, use of a rubber dam during treatment and cases involving primary root canal treatment as opposed to retreatment. Other factors have the potential to affect success rates, but these have not yet been quantified. Although there is an array of potential factors that influence the outcome of endodontic treatment, success is most significantly dependent upon the elimination of root canal infection present when treatment starts and the prevention of contamination during treatment.
Monitoring in Language Perception
Authors: Van De Meerendonk Nan , Kolk Herman H.J. , Chwilla Dorothee J. , Vissers Constance Th.W.M.
Published: August 2009

Monitoring is an aspect of executive control that entails the detection of errors and the triggering of corrective actions when there is a mismatch between competing responses or representations. In the language domain, research of monitoring has mainly focused on errors made during language production. However, in language perception, for example while reading or listening, errors occur as well and people are able to detect them. A hypothesis that was developed to account for these errors is the monitoring hypothesis for language perception. According to this account, when a strong expectation conflicts with what is actually observed, a reanalysis is triggered to check the input for processing errors reflected by the P600 component. In contrast to what has been commonly assumed, the P600 is thought to reflect a general reanalysis and not a syntactic reanalysis. In this review, we will describe the different studies that led to this hypothesis and try to extend it beyond the language domain.
Production of Resistant Starch by Extrusion Cooking of Acid‐Modified Normal‐Maize Starch
Authors: Hasjim Jovin , Jane Jay‐lin
Published: August 2009

ABSTRACT:  The objective of this study was to utilize extrusion cooking and hydrothermal treatment to produce resistant starch (RS) as an economical alternative to a batch‐cooking process. A hydrothermal treatment (110 °C, 3 d) of batch‐cooked and extruded starch samples facilitated propagation of heat‐stable starch crystallites and increased the RS contents from 2.1% to 7.7% up to 17.4% determined using AOAC Method 991.43 for total dietary fiber. When starch samples were batch cooked and hydrothermally treated at a moisture content below 70%, acid‐modified normal‐maize starch (AMMS) produced a greater RS content than did native normal‐maize starch (NMS). This was attributed to the partially hydrolyzed, smaller molecules in the AMMS, which had greater mobility and freedom than the larger molecules in the NMS. The RS contents of the batch‐cooked and extruded AMMS products after the hydrothermal treatment were similar. A freezing treatment of the AMMS samples at −20 °C prior to the hydrothermal treatment did not increase the RS content. The DSC thermograms and the X‐ray diffractograms showed that retrograded amylose and crystalline starch–lipid complex, which had melting temperatures above 100 °C, accounted for the RS contents.
Evaluation of Combined Antibacterial Effects of Eugenol, Cinnamaldehyde, Thymol, and Carvacrol against E. coli with an Improved Method
Authors: Pei Rui‐song , Zhou Feng , Ji Bao‐ping , Xu Jing
Published: August 2009

ABSTRACT:  In this study, the antibacterial activities of eugenol, cinnamaldehyde, thymol, carvacrol, and their combinations against E. coli were investigated separately. First, broth macro‐dilution assay was adopted to determine the minimal inhibitory concentration (MIC) of the 4 components. Second, the combination testing was performed using chequerboard method. Finally, the combined effects were evaluated with an improved method, which was based on the indices of fractional inhibitory concentration (FIC) and Effect of the Combination (EC) jointly. The results indicated that MICs of the 4 components were 1600, 400, 400, and 400 mg/L, respectively; treatments with cinnamaldehyde/eugenol, thymol/eugenol, carvacrol/eugenol, and thymol/carvacrol revealed synergistic effects according to the 2 indices. By means of combination, MICs of eugenol, cinnamaldehyde, thymol, and carvacrol decreased to 400, 100, 100, and 100 mg/L, respectively. Consequently, the negative impacts of unpleasant smell of these 4 components could be minimized, making it possible to add them to foods as preservatives. In addition, this improved evaluation method provided a more accurate and comprehensive way to evaluate combined effects.
Isolation and Molecular Characterization of Multidrug‐Resistant Strains of Escherichia coli and Salmonella from Retail Chicken Meat in Japan
Authors: Ahmed Ashraf M. , Shimabukuro Hirofumi , Shimamoto Tadashi
Published: August 2009

ABSTRACT:  Sixty‐nine Escherichia coli and 10 Salmonella isolates, recovered from retail chicken meat in Hiroshima prefecture, Japan, were assayed for antimicrobial susceptibility, the presence of integrons and antimicrobial resistance genes. Twenty‐eight out of 69 (40.6%) of E. coli and all 10 Salmonella isolates were exhibited multidrug resistance phenotypes. The most commonly reported resistance phenotypes were against ampicillin, streptomycin, spectinomycin, kanamycin, tetracycline, and trimethoprim/sulfamethoxazole. PCR screening for integrons showed that 8 (11.6%) of the E. coli isolates were positive for the class 1 integrons and 1 isolate (1.4%) was positive for the class 2 integrons. Among the 10 Salmonella isolates, 9 were positive for class 1 integrons and none was positive for class 2 integrons. The identified antibiotic resistance gene cassettes within the class 1 integrons were dfrA1, dfrA7, aadA1, aadB, and catB3, while dfrA1, sat2, and aadA1 were identified within class 2 integron. The β‐lactamase resistance gene blaTEM‐1 was identified in 12 (17.3%) of E. coli isolates and in only one of the Salmonella isolates. The blaCMY‐2 gene, encoding AmpC β‐lactamase, was detected in 16 (23.2%) of the E. coli isolates only. Conjugation experiments demonstrated that there was plasmid‐mediated transfer of blaCMY‐2 and blaTEM‐1. These results highlighted the role of retail chicken meat as a potential source for multidrug‐resistant strains of E. coli and Salmonella. To the best of our knowledge, this is the 1st report of isolation and molecular characterization of multidrug‐resistant strains of E. coli from retail chicken meat in Japan.
Enhancing Safety and Aroma Appealing of Fresh‐Cut Fruits and Vegetables Using the Antimicrobial and Aromatic Power of Essential Oils
Authors: Ayala‐Zavala J. Fernando , González‐Aguilar Gustavo A. , Del‐Toro‐Sánchez L.
Published: August 2009

ABSTRACT: Microbial and aroma attributes are within the most decisive factors limiting safety and sensory appealing of fresh‐cut fruits and vegetables. Alternatively, several plant essential oils (EOs) are constituted of several volatile active compounds and most of them present antimicrobial potential and had different aroma profile. Considering these premises, this hypothesis article states that safety and aroma appealing of fresh‐cut produce could be improved with EO treatment. EOs could prevent fresh‐cut fruit decay; however, their volatile constituents could be sorbed by the produce, and according to the aroma notes of the antimicrobial oil, sensorial appealing of odor, and flavor of the treated produce might be affected positively or negatively. Specifically, garlic oil is a natural antimicrobial constituted by sulfur compounds, which are responsible for its odor and antimicrobial properties. Besides, fresh‐cut tomato is a highly perishable product that needs antimicrobial agents to preserve its quality and safety for a longer period of time. From the sensorial point of view, aroma combination of garlic and tomato is a common seasoning practice in Europe and America and well accepted by consumers. Once the right combination of flavors between the EOs and the fresh‐cut produce has been selected, safety and quality of the treated fruit could be improved by adding antimicrobial protection and extra aroma. Therefore, other combinations between EOs and fresh‐cut produce are discussed. This approximation could reinforce the trends of natural food preservation, accomplishing the demands of the increasing sector of consumers demanding tasty and convenient fresh‐cut produce, containing only natural ingredients.
New advances in pharmacotherapy for early psychosis
Authors: Emsley Robin
Published: August 2009

Aim: This review examines the use of antipsychotic medication during the early years of psychosis.

Methods: A selective literature review was conducted.

Results: The early years of schizophrenia represent a critical period for intervention. Importantly, first‐episode patients differ from those with chronic schizophrenia in several important respects. While treatment response to antipsychotic medication is better, the risk of relapse is also higher. While both first‐ and second‐generation antipsychotics are very effective in reducing symptoms, there are tolerability and some efficacy advantages for the second‐generation antipsychotics in first‐episode psychosis. Poor medication adherence is a significant problem in early psychosis that is linked to relapse and poses a major barrier to optimizing outcomes. Treatment strategies should focus on, among other things, improving antipsychotic medication adherence.

Conclusions: The early years of psychosis offer the best opportunity for achieving optimal outcomes. Maintaining symptomatic remission is central to achieving functional recovery.
Donaldson–Thomas theory of 𝒜n×P1
Authors: Maulik Davesh , Oblomkov Alexei
Published: August 2009

We study the relative Donaldson–Thomas theory of 𝒜n×P1, where 𝒜n is the surface resolution of type An singularity. The action of divisor operators in the theory is expressed in terms of operators of the affine algebra $\glh $ on Fock space. Assuming a nondegeneracy conjecture, this gives a complete solution for the theory. The results complete the comparison of this theory with the Gromov–Witten theory of 𝒜n×P1 and the quantum cohomology of the Hilbert scheme of points on 𝒜n.
Thermodynamic Effect on Rotating Cavitation in an Inducer
Authors: Yoshida Yoshiki , Sasao Yoshifumi , Watanabe Mitsuo , Hashimoto Tomoyuki , Iga Yuka , Ikohagi Toshiaki
Published: August 2009

Cavitation in cryogenic fluids has a thermodynamic effect because of the thermal imbalance around the cavity. It improves cavitation performances in turbomachines due to the delay of cavity growth. The relationship between the thermodynamic effect and cavitation instabilities, however, is still unknown. To investigate the influence of the thermodynamic effect on rotating cavitation appeared in the turbopump inducer, we conducted experiments in which liquid nitrogen was set at different temperatures (74 K, 78 K, and 83 K) with a focus on the cavity length. At higher cavitation numbers, supersynchronous rotating cavitation occurred at the critical cavity length of Lc/h≅0.5 with a weak thermodynamic effect in terms of the fluctuation of cavity length. In contrast, synchronous rotating cavitation occurred at the critical cavity length of Lc/h≅0.9–1.0 at lower cavitation numbers. The critical cavitation number shifted to a lower level due to the suppression of cavity growth by the thermodynamic effect, which appeared significantly with rising liquid temperature. The unevenness of cavity length under synchronous rotating cavitation was decreased by the thermodynamic effect. Furthermore, we confirmed that the fluid force acting on the inducer notably increased under conditions of rotating cavitation, but that the amplitude of the shaft vibration depended on the degree of the unevenness of the cavity length through the thermodynamic effect.
Measurements of High Velocity Gradient Flow Using Bubble Tracers in a Cavitation Tunnel
Authors: Paik Bu-Geun , Kim Kyung-Youl , Ahn Jong-Woo
Published: August 2009

The objective of the present study is to investigate propeller wake using particle image velocimetry (PIV) technique with bubble type of tracers, naturally generated by the decrease in the static pressure in a cavitation tunnel. The bubble can be grown from the nuclei melted in the water tunnel and the size of bubbles is changed by varying the tunnel pressure. A series of experiments are conducted in the conditions of the uniform and high velocity gradient flows to find out the characteristics of bubble tracers and compared the measurement results using bubbles with those using solid particles. Bubbles showed good trace ability in the region of 15<ReS<75; however, some discrepancies showed at high velocity gradient region of ReS≈1000. The fitted vorticity reduction rate would give reference for the prediction in a real flow when bubble tracers are utilized in PIV measurements of a vortical flow. In addition, the characteristics of bubble slip velocity can provide information on the vortex core center and the reduction in the Reynolds shear stress caused by bubble’s deformability.
Transition of Bubbly Flow in Vertical Tubes: New Criteria Through CFD Simulation
Authors: Das A. K. , Das P. K. , Thome J. R.
Published: August 2009

The two fluid model is used to simulate upward gas-liquid bubbly flow through a vertical conduit. Coalescence and breakup of bubbles have been accounted for by embedding the population balance technique in the two fluid model. The simulation enables one to track the axial development of the voidage pattern and the distribution of the bubbles. Thereby it has been possible to propose a new criterion for the transition from bubbly to slug flow regime. The transition criteria depend on (i) the breakage and coalescence frequency, (ii) the bubble volume count below and above the bubble size introduced at the inlet, and (iii) the bubble count histogram. The prediction based on the present criteria exhibits excellent agreement with the experimental data. It has also been possible to simulate the transition from bubbly to dispersed bubbly flow at a high liquid flow rate using the same model.
Transition of Bubbly Flow in Vertical Tubes: Effect of Bubble Size and Tube Diameter
Authors: Das A. K. , Das P. K. , Thome J. R.
Published: August 2009

In a companion paper (“Modelling Bubbly Flow by Population Balance Technique Part I: Axial Flow Development and Its Transitions,” ASME J. Fluids Eng), a two fluid model along with a multiclass population balance technique has been used to find out comprehensive criteria for the transition from bubbly to slug flow, primarily through a study of axial flow development. Using the same basic model the transition mechanism has been investigated in the present paper covering a wide range of process parameters. Though the dominating rate of bubble coalescence during the axial development of the flow acts as the main cause for the transition to slug flow, the simultaneous transformation of the radial voidage pattern cannot be overlooked. Appearance of core, intermediate, wall, and two peaks are observed in the radial voidage distribution depending on the phase superficial velocities. A map has been developed indicating the boundaries of the above subregimes. It has been observed that not only the size of the bubbles entering the inlet plane but also the size distribution (monodispersion or bidispersion) changes the voidage peak and shifts the transition boundary. It is interesting to note that the bubbly flow only with a core peak void distribution transforms into slug flow with a change in the operating parameters. Transition boundary is also observed to shift with a change in the tube diameter. The simulation results have been compared with experimental data taken from different sources and very good agreements have been noted.
Atmospheric Carbon Dioxide Concentration Across the Mid-Pleistocene Transition
Authors: Hönisch Bärbel , Hemming N. Gary , Archer David , Siddall Mark , McManus Jerry F.
Published: August 2009

A Change in the Air?

Between around 1.2 million and 500,000 years ago, Earth's glacial cycle changed from one with a period of roughly 40,000 years to one with a period of about 100,000 years. Although there has been much speculation about why this transition may have occurred, no potential explanation seemed more likely than that it was caused by decreasing concentrations of atmospheric CO
2
.

Hönisch
et al.

(p.
1551
) present a record of atmospheric
p
CO
2
for the past 2.1 million years, derived from the boron isotopic composition of planktonic foraminifera, and show that the amount of CO
2
in the atmosphere has remained relatively constant over that period. While
p
CO
2
was approximately 30 ppm higher before the start of the mid-Pleistocene transition than after the transition, atmospheric CO
2
did not decrease gradually as would be expected were it to be the driver of the transition.
Light-Induced Spontaneous Magnetization in Doped Colloidal Quantum Dots
Authors: Beaulac Rémi , Schneider Lars , Archer Paul I. , Bacher Gerd , Gamelin Daniel R.
Published: August 2009

Saturated Magnetism in Photoexcited Nanocrystals

Switching the magnetic state of semiconductors with either an electric field or by light absorption is a key requirement for spintronics, in which devices are based on electronic spin state rather than charge. In semiconductor nanoparticles doped with magnetic ions, excitons can form a spin state, a magnetic polaron, but often the effect is limited to low temperatures (below 30 kelvin) and does not saturate in the absence of an applied magnetic field.

Beaulac
et al.

(p.
973
) report the synthesis of Mn-doped CdSe nanocrystals in which the quantum confinement effects lead to long exciton lifetimes. Photoexcitation results in exchange fields that can exceed 30 Tesla at low temperatures and that persist even up to room temperature in the absence of an applied magnetic field.
Visualization of Fermi’s Golden Rule Through Imaging of Light Emission from Atomic Silver Chains
Authors: Chen Chi , Bobisch C. A. , Ho W.
Published: August 2009

Silver Emission Follows Golden Rule

Electrons emitted from the tip of a scanning tunneling microscope (STM) can be used in certain cases to excite optical emission from surface structure. Such methods can be used to characterize the “particle-in-a-box” states created in chains of varying lengths of metal atoms on surfaces.

Chen
et al.

(p.
981
) were able to spatially resolve photon emission for silver chains up to 10 atoms long, assembled on a nickel-aluminum alloy surface. The emission maxima correlated with the nodes seen in the derivative of STM current with voltage. This correlation follows from Fermi's golden rule, which connects the initial and final states of the radiation transition through the momentum operator and leads to a better understanding of the light-emission process.
Is Gas Hydrate Energy Within Reach?
Authors: Boswell Ray
Published: August 2009

A new focus of the most recoverable gas hydrate deposits is shortening the timeline for the future production of natural gas from this vast resource.
What Is It Like to Be a Cell?
Wetware
A Computer in Every Living Cell

by Dennis Bray

Yale University Press, New Haven, CT, 2009. 279 pp. $28, £18.99. ISBN 9780300141733.
Authors: Marshall Wallace F.
Published: August 2009

Taking a systems biology approach, Bray argues that the chemistry of living cells constitutes a form of computation.
Outcome of Acute Prosthetic Joint Infections Due to Gram-Negative Bacilli Treated with Open Debridement and Retention of the Prosthesis
Authors: Martínez-Pastor Juan C. , Muñoz-Mahamud Ernesto , Vilchez Félix , García-Ramiro Sebastián , Bori Guillem , Sierra Josep , Martínez José A. , Font Lluis , Mensa Josep , Soriano Alex
Published: August 2009

The aim of our study was to evaluate the outcome of acute prosthetic joint infections (PJIs) due to gram-negative bacilli (GNB) treated without implant removal. Patients with an acute PJI due to GNB diagnosed from 2000 to 2007 were prospectively registered. Demographics, comorbidity, type of implant, microbiology data, surgical treatment, antimicrobial therapy, and outcome were recorded. Classification and regression tree analysis, the Kaplan-Meier survival method, and the Cox regression model were applied. Forty-seven patients were included. The mean age was 70.7 years, and there were 15 hip prostheses and 32 knee prostheses. The median number of days from the time of arthroplasty was 20. The most frequent pathogens were members of the
Enterobacteriaceae
family in 41 cases and
Pseudomonas
spp. in 20 cases. Among the
Enterobacteriaceae
, 14 were resistant to ciprofloxacin, while all
Pseudomonas aeruginosa
isolates were susceptible to ciprofloxacin. The median durations of intravenous and oral antibiotic treatment were 14 and 64 days, respectively. A total of 35 (74.5%) patients were in remission after a median follow-up of 463 days (interquartile range, 344 to 704) days. By use of the Kaplan-Meier survival curve, a C-reactive protein (CRP) concentration of ≤15 mg/dl (
P
= 0.03) and receipt of a fluoroquinolone, when all GNB isolated were susceptible (
P
= 0.0009), were associated with a better outcome. By use of a Cox regression model, a CRP concentration of ≤15 mg/dl (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.05 to 12.5;
P
= 0.043) and receipt of a fluoroquinolone (OR, 9.09; 95% CI, 1.96 to 50;
P
= 0.005) were independently associated with better outcomes. Open debridement without removal of the implant had a success rate of 74.5%, and the factors associated with good prognosis were a CRP concentration at the time of diagnosis ≤15 mg/dl and treatment with a fluoroquinolone.
Comparison of Human Immunodeficiency Virus Type 1 Tropism Profiles in Clinical Samples by the Trofile and MT-2 Assays
Authors: Coakley Eoin , Reeves Jacqueline D. , Huang Wei , Mangas-Ruiz Marga , Maurer Irma , Harskamp Agnes M. , Gupta Soumi , Lie Yolanda , Petropoulos Christos J. , Schuitemaker Hanneke , van 't Wout Angélique B.
Published: August 2009

The recent availability of CCR5 antagonists as anti-human immunodeficiency virus (anti-HIV) therapeutics has highlighted the need to accurately identify CXCR4-using variants in patient samples when use of this new drug class is considered. The Trofile assay (Monogram Biosciences) has become the method that is the most widely used to define tropism in the clinic prior to the use of a CCR5 antagonist. By comparison, the MT-2 assay has been used since early in the HIV epidemic to define tropism in clinical specimens. Given that there are few data from direct comparisons of these two assays, we evaluated the performance of the plasma-based Trofile assay and the peripheral blood mononuclear cell (PBMC)-based MT-2 assay for the detection of CXCR4 use in defining the tropism of HIV isolates derived from clinical samples. The various samples used for this comparison were derived from participants of the Amsterdam Cohort Studies on HIV infection and AIDS who underwent consecutive MT-2 assay testing of their PBMCs at approximately 3-month intervals. This unique sample set was specifically selected because consecutive MT-2 assays had demonstrated a shift from negative to positive in PBMCs, reflecting the first emergence of CXCR4-using virus in PBMCs above the level of detection of the assay in these individuals. Trofile testing was performed with clonal HIV type 1 (HIV-1) variants (n= 21), MT-2 cell culture-derived cells (n= 20) and supernatants (n= 42), and plasma samples (n= 76). Among the clonal HIV-1 variants and MT-2 cell culture-derived samples, the results of the Trofile and MT-2 assays demonstrated a high degree of concordance (95% to 98%). Among consecutive plasma samples, detection of CXCR4-using virus was at or before the time of first detection by the MT-2 assay in 5/10 patients by the original Trofile assay and in 9/10 patients by the enhanced-sensitivity Trofile assay. Differences in the time to the first detection of CXCR4 use between the MT-2 assay (PBMCs) and the original Trofile assay (plasma) were greatly reduced by the enhanced-sensitivity Trofile assay, suggesting that sensitivity for the detection of minor CXCR4-using variants may be a more important determinant of discordant findings than compartmentalization. The similarities in performance of the enhanced-sensitivity Trofile and MT-2 assays suggest that either may be an appropriate methodology to define tropism in patient specimens.
New Selectable Marker for Manipulating the Simple Genomes of
Mycoplasma
Species
Authors: Algire Mikkel A. , Lartigue Carole , Thomas David W. , Assad-Garcia Nacyra , Glass John I. , Merryman Chuck
Published: August 2009

Over the past several years, significant advances have been made in the molecular genetics of the
Mollicutes
(the simplest cells that can be grown in axenic culture). Nevertheless, a number of basic molecular tools are still required before genetic manipulations become routine. Here we describe the development of a new dominant selectable marker based on the enzyme puromycin-
N
-acetyltransferase from
Streptomyces alboniger
. Puromycin is an antibiotic that mimics the 3′-terminal end of aminoacylated tRNAs and attaches to the carboxyl terminus of growing protein chains. This stops protein synthesis. Because puromycin conscripts rRNA recognition elements that are used by all of the various tRNAs in a cell, it is unlikely that spontaneous antibiotic resistance can be acquired via a simple point mutation—an annoying issue with existing mycoplasma markers. Our codon-optimized cassette confers pronounced puromycin resistance on all five of the mycoplasma species we have tested so far. The resistance cassette was also designed to function in
Escherichia coli
, which simplifies the construction of shuttle vectors and makes it trivial to produce the large quantities of DNA generally necessary for mycoplasma transformation. Due to these and other features, we expect the puromycin marker to be a widely applicable tool for studying these simple cells and pathogens.
Molecular Epidemiology of CTX-M-Producing
Escherichia coli
Isolates at a Tertiary Medical Center in Western Pennsylvania
Authors: Sidjabat Hanna E. , Paterson David L. , Adams-Haduch Jennifer M. , Ewan Lindsay , Pasculle Anthony W. , Muto Carlene A. , Tian Guo-Bao , Doi Yohei
Published: August 2009

A combination of phenotypic and genotypic methods was used to investigate 70 unique
Escherichia coli
clinical isolates identified as producing extended-spectrum β-lactamases (ESBLs) at a medical center in Pittsburgh, PA, between 2007 and 2008. Fifty-seven isolates (81%) produced CTX-M-type ESBLs, among which CTX-M-15 was predominant (
n
= 46). Isolates producing CTX-M-2, -9, -14, and -65 were also identified. One CTX-M-producing isolate coproduced CMY-2 cephalosporinase. Ten isolates (14%) produced SHV-type ESBLs, either SHV-5 or SHV-7. Two isolates produced only CMY-2 or -32. Pulsed-field gel electrophoresis revealed the presence of two major clusters of CTX-M-15-producing
E. coli
isolates, one in phylotype B2 (
n
= 15) and the other in phylotype A (
n
= 19). Of four phylotype B2 isolates that were able to transfer the
bla
CTX-M-15
-carrying plasmids, three showed fingerprints related (>60%) to those of plasmids from phylotype A isolates. In phylotype B2, all CTX-M-15-producing isolates, as well as three isolates producing CTX-M-14, two producing SHV-5, and one producing SHV-7, belonged to the international epidemic clone defined by serotype O25:H4 and sequence type 131. The plasmids from eight of nine CTX-M-15-producing
E. coli
isolates of phylotype A that were examined were highly related to each other and were also found in two isolates belonging to phylotype D, suggesting horizontal transfer of this
bla
CTX-M-15
-carrying plasmid between phylotypes. Our findings underscore the need to further investigate the epidemiology and virulence of CTX-M-producing
E. coli
in the United States.
Susceptibility of Urinary Tract Bacteria to Fosfomycin
Authors: Maraki Sofia , Samonis George , Rafailidis Petros I. , Vouloumanou Evridiki K. , Mavromanolakis Emmanuel , Falagas Matthew E.
Published: August 2009

We evaluated the in vitro activity of fosfomycin against urinary isolates in a region in Greece that exhibits considerable antimicrobial resistance by evaluating retrospectively relevant susceptibility data retrieved from the microbiological library of the University Hospital of Heraklion, Crete, Greece. We examined 578 urinary isolates. In total, 516 (89.2%) were susceptible to fosfomycin; 415 isolates were gram negative, and 101 isolates were gram positive. Fosfomycin appears to exhibit good levels of in vitro activity against the examined urinary isolates.
Regional Dissemination of KPC-Producing
Klebsiella pneumoniae
Authors: Kitchel Brandon , Sundin Daniel R. , Patel Jean B.
Published: August 2009

Production of a
Klebsiella pneumoniae
carbapenemase (KPC) is the most common mechanism of carbapenem resistance in the United States; however, until now, KPC-producing isolates have not been found in western Michigan. Molecular typing of two KPC-producing
K. pneumoniae
isolates from Michigan showed their similarity to other Midwestern isolates. They were also unrelated to the dominant sequence type observed throughout the United States, multilocus sequence type 258. This could represent regional dissemination of another KPC-producing
K. pneumoniae
strain.
Impact of Spore Biology on the Rate of Kill and Suppression of Resistance in
Bacillus anthracis
Authors: Drusano G. L. , Okusanya O. O. , Okusanya A. O. , van Scoy B. , Brown D. L. , Fregeau C. , Kulawy R. , Kinzig M. , Sörgel F. , Heine H. S. , Louie A.
Published: August 2009

Bacillus anthracis
is complex because of its spore form. The spore is invulnerable to antibiotic action. It also has an impact on the emergence of resistance. We employed the hollow-fiber infection model to study the impacts of different doses and schedules of moxifloxacin on the total-organism population, the spore population, and the subpopulations of vegetative- and spore-phase organisms that were resistant to moxifloxacin. We then generated a mathematical model of the impact of moxifloxacin, administered by continuous infusion or once daily, on vegetative- and spore-phase organisms. The ratio of the rate constant for vegetative-phase cells going to spore phase (
K
vs
) to the rate constant for spore-phase cells going to vegetative phase (
K
sv
) determines the rate of organism clearance. The continuous-infusion drug profile is more easily sensed as a threat; the
K
vs
/
K
sv
ratio increases at lower drug exposures (possibly related to quorum sensing). This movement to spore phase protects the organism but makes the emergence of resistance less likely. Suppression of resistance requires a higher level of drug exposure with once-daily administration than with a continuous infusion, a difference that is related to vegetative-to-spore (and back) transitioning. Spore biology has a major impact on drug therapy and resistance suppression. These findings explain why all drugs of different classes have approximately the same rate of organism clearance for
Bacillus anthracis
.
Interaction of Aminoglycosides with Human Mitochondrial 12S rRNA Carrying the Deafness-Associated Mutation
Authors: Qian Yaping , Guan Min-Xin
Published: August 2009

The mitochondrial 12S rRNA A1555G mutation is one of the important causes of aminoglycoside-induced and nonsyndromic hearing loss. Here we employed an RNA-directed chemical-modification approach to understanding the pathogenesis of aminoglycoside-induced hearing loss. The patterns of chemical modification of RNA oligonucleotides carrying the A1555G mutation by dimethyl sulfate (DMS) were distinct from those of the RNA oligonucleotides carrying wild-type sequence in the presence of aminoglycosides. In the RNA analogue carrying the A1555G mutation, reduced reactivity to DMS occurred in base G1555 as well as in bases C1556 and A1553 in the presence of paromomycin, neomycin, gentamicin, kanamycin, tobramycin, or streptomycin. In particular, base G1555 exhibited marked but similar levels of protection in the presence of 0.1 μM to 100 μM neomycin, gentamicin, or kanamycin. In contrast, the levels of protection in base G1555 appeared to be correlated with the concentration of paromycin, tobramycin, or steptomycin. Furthermore, increasing reactivities to DMS in the presence of these aminoglycosides were observed for bases A1492, C1493, C1494, and A1557 in the RNA analogue carrying the A1555G mutation. These data suggested that the A1555G mutation altered the binding properties of aminoglycosides at the A site of 12S rRNA and led to local conformational changes in 12S rRNA carrying the A1555G mutation. The interaction between aminoglycosides and 12S rRNA carrying the A1555G mutation provides new insight into the pathogenesis of aminoglycoside ototoxicity.
Antifungal Activity of Micafungin in Serum
Authors: Ishikawa Jun , Maeda Tetsuo , Matsumura Itaru , Yasumi Masato , Ujiie Hidetoshi , Masaie Hiroaki , Nakazawa Tsuyoshi , Mochizuki Nobuo , Kishino Satoshi , Kanakura Yuzuru
Published: August 2009

We have evaluated the antifungal activity of micafungin in serum by using the disk diffusion method with serum-free and serum-added micafungin standard curves. Serum samples from micafungin-treated patients have been shown to exhibit adequate antifungal activity, which was in proportion to both the applied dose and the actual concentration of micafungin measured by high-performance liquid chromatography. The antifungal activity of micafungin in serum was also confirmed with the broth microdilution method.
Absence of
Neisseria meningitidis
Serogroup C-Specific Antibodies during the First Year of Life in The Netherlands: an Age Group at Risk?
Authors: de Voer Richarda M. , van der Klis Fiona R. M. , Niers Laetitia E. M. , Rijkers Ger T. , Berbers Guy A. M.
Published: August 2009

In The Netherlands, a single meningococcal serogroup C conjugate (MenCC) vaccination is administered to children at the age of 14 months. Here, we report the levels of MenC polysaccharide-specific antibodies in children at birth and at 3, 11, and 12 months of age and the presence of functional antibodies at 11 months of age, before infants receive their MenCC immunization. We observed a rapid decline in polysaccharide-specific antibodies after birth and no induction of naturally elicited polysaccharide-specific antibodies. Furthermore, at 11 months of age, no bactericidal antibodies are observed. These data indicate that these infants may be at risk in the period prior to MenCC immunization, if
Neisseria meningitidis
serogroup C starts to (re)circulate.
Clinical Evaluation of a (1,3)-β-
d
-Glucan Assay for Presumptive Diagnosis of
Pneumocystis jiroveci
Pneumonia in Immunocompromised Patients
Authors: Del Bono Valerio , Mularoni Alessandra , Furfaro Elisa , Delfino Emanuele , Rosasco Lorenzo , Miletich Franca , Viscoli Claudio
Published: August 2009

(1,3)-β-
d
-Glucan (BG) is a component of the
Pneumocystis jiroveci
cell wall. Thirty-one immunocompromised patients with pneumonia (16 with presumptive pneumocystis pneumonia [PCP] and 15 with non-PCP) were evaluated for serum BG levels. Serum from all 16 presumptive PCP patients and from 2/15 patients with non-PCP was positive for BG. Results indicate that BG is a reliable marker for diagnosing PCP.
A Multifunctional, Synthetic
Gaussia princeps
Luciferase Reporter for Live Imaging of
Candida albicans
Infections
Authors: Enjalbert Brice , Rachini Anna , Vediyappan Govindsamy , Pietrella Donatella , Spaccapelo Roberta , Vecchiarelli Anna , Brown Alistair J. P. , d'Enfert Christophe
Published: August 2009

Real-time monitoring of the spatial and temporal progression of infection/gene expression in animals will contribute greatly to our understanding of host-pathogen interactions while reducing the number of animals required to generate statistically significant data sets. Sensitive in vivo imaging technologies can detect low levels of light emitted from luciferase reporters in vivo, but the existing reporters are not optimal for fungal infections. Therefore, our aim was to develop a novel reporter system for imaging
Candida albicans
infections that overcomes the limitations of current luciferase reporters for this major fungal pathogen. This luciferase reporter was constructed by fusing a synthetic, codon-optimized version of the
Gaussia princeps
luciferase gene to
C. albicans PGA59
, which encodes a glycosylphosphatidylinositol-linked cell wall protein. Luciferase expressed from this
PGA59-gLUC
fusion (referred to as
gLUC59
) was localized at the
C. albicans
cell surface, allowing the detection of luciferase in intact cells. The analysis of fusions to strong (
ACT1
and
EFT3
), oxidative stress-induced (
TRX1
,
TRR1
, and
IPF9996
), and morphogenesis-dependent (
HWP1
) promoters confirmed that
gLUC59
is a convenient and sensitive reporter for studies of gene regulation in yeast or hyphal cells, as well as a flexible screening tool. Moreover, the
ACT1
-
gLUC59
fusion represented a powerful tool for the imaging of disease progression in superficial and subcutaneous
C. albicans
infections.
gLUC59
and related cell surface-exposed luciferase reporters might find wide applications in molecular biology, cell biology, pathobiology, and high-throughput screens.
The Membrane Localization Domain Is Required for Intracellular Localization and Autoregulation of YopE in
Yersinia pseudotuberculosis
Authors: Isaksson Elin L. , Aili Margareta , Fahlgren Anna , Carlsson Sara E. , Rosqvist Roland , Wolf-Watz Hans
Published: August 2009

Recent work has shown that a domain of YopE of
Yersinia pseudotuberculosis
ranging from amino acids 54 to 75 (R. Krall, Y. Zhang, and J. T. Barbieri, J. Biol. Chem. 279:2747-2753, 2004) is required for proper localization of YopE after ectopic expression in eukaryotic cells. This domain, called the membrane localization domain (MLD), has not been extensively studied in
Yersinia
. Therefore, an in
cis
MLD deletion mutant of YopE was created in
Y. pseudotuberculosis
. The mutant was found to secrete and translocate YopE at wild-type levels. However, the mutant was defective in the autoregulation of YopE expression after the infection of HeLa cells. Although the mutant translocated YopE at wild-type levels, it showed a delayed HeLa cell cytotoxicity. This delay was not caused by a change in GTPase activating protein (GAP) activity, since the mutant showed wild-type YopE GAP activity toward Rac1 and RhoA. The MLD mutant displayed a changed intracellular localization pattern of YopE in HeLa cells after infection, and the YopEΔMLD protein was found to be dispersed within the whole cell, including the nucleus. In contrast, wild-type YopE was found to localize to the perinuclear region of the cell and was not found in the nucleus. In addition, the
yopE
ΔMLD mutant was avirulent. Our results suggest that YopE must target proteins other than RhoA and Rac1 and that the MLD is required for the proper targeting and hence virulence of YopE during infection. Our results raise the question whether YopE is a regulatory protein or a “true” virulence effector protein.
Streptolysin S Inhibits Neutrophil Recruitment during the Early Stages ofStreptococcus pyogenesInfection
Authors: Lin Ada , Loughman Jennifer A. , Zinselmeyer Bernd H. , Miller Mark J. , Caparon Michael G.
Published: August 2009

In contrast to infection of superficial tissues,Streptococcus pyogenesinfection of deeper tissue can be associated with a significantly diminished inflammatory response, suggesting that this bacterium has the ability to both promote and suppress inflammation. To examine this, we analyzed the behavior of anS. pyogenesmutant deficient in expression of the cytolytic toxin streptolysin S (SLS−) and evaluated events that occur during the first few hours of infection by using several models including injection of zebrafish (adults, larvae, and embryos), a transepithelial polymorphonuclear leukocyte (PMN) migration assay, and two-photon microscopy of mice in vivo. In contrast to wild-typeS. pyogenes, the SLS−mutant was associated with the robust recruitment of neutrophils and significantly reduced lethal myositis in adult zebrafish. Similarly, the mutant was attenuated in embryos in its ability to cause lethality. Infection of larva muscle allowed an analysis of inflammation in real time, which revealed that the mutant had recruited PMNs to the infection site. Analysis of transepithelial migration in vitro suggested that SLS inhibited the host cells' production of signals chemotactic for neutrophils, which contrasted with the proinflammatory effect of an unrelated cytolytic toxin, streptolysin O. Using two-photon microscopy of mice in vivo, we showed that the extravasation of neutrophils during infection with SLS−mutant bacteria was significantly accelerated compared to infection with wild-typeS. pyogenes. Taken together, these data support a role for SLS in the inhibition of neutrophil recruitment during the early stages ofS. pyogenesinfection.
PspA Family Fusion Proteins Delivered by AttenuatedSalmonella entericaSerovar Typhimurium Extend and Enhance Protection againstStreptococcus pneumoniae
Authors: Xin Wei , Li Yuhua , Mo Hua , Roland Kenneth L. , Curtiss Roy
Published: August 2009

Pneumococcal surface protein A (PspA) is highly immunogenic and can induce a protective immune response against pneumococcal infection. PspA is divided into two major families based on serological variability: family 1 and family 2. To provide broad protection, PspA proteins from pneumococcal strains Rx1 (family 1) and EF5668 (family 2) were combined to form two PspA fusion proteins, PspA/Rx1-EF5668 and PspA/EF5668-Rx1. Each protein was fused to a type II secretion signal and delivered by a recombinant attenuatedSalmonellavaccine (RASV). Both PspA/Rx1-EF5668 and PspA/EF5668-Rx1 were synthesized in the RASV and secreted into the periplasm and supernatant. The fusion proteins reacted strongly with both anti-PspA/Rx1 and anti-PspA/EF5668 antisera. Oral immunization of BALB/c mice with RASV synthesizing either PspA fusion protein elicited serum immunoglobulin G (IgG) and mucosal IgA responses against both families of PspA. Analysis of IgG isotypes (IgG2a and IgG1) indicated a strong Th1 bias to the immune responses to both proteins. Sera from mice immunized with RASV synthesizing PspA/Rx1-EF5668 bound to the surface and directed C3 complement deposition on representative strains from all five PspA clades. Immunization with RASV synthesizing either protein protected mice against intraperitoneal challenge withStreptococcus pneumoniaeWU2 strain (family 1), intravenous challenge withS. pneumoniae3JYP2670 strain (family 2), and intranasal challenge withS. pneumoniaeA66.1 (family 1). The PspA/Rx1-EF5668 protein elicited significantly greater protection than PspA/EF5668-Rx1, PspA/Rx1, or PspA/EF5668. These results indicate an RASV synthesizing a PspA fusion protein representing both PspA families constitutes an effective antipneumococcal vaccine, extending and enhancing protection against multiple strains ofS. pneumoniae.