bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic and Biochemical Characterization of OXA-405, an OXA-48-Type Extended-Spectrum β-Lactamase without Significant Carbapenemase Activity
Authors: Dortet Laurent , Oueslati Saoussen , Jeannot Katy , Tandé Didier , Naas Thierry , Nordmann Patrice 
Published: April 2015

ABSTRACT

The epidemiology of carbapenemases worldwide is showing that OXA-48 variants are becoming the predominant carbapenemase type in
Enterobacteriaceae
in many countries. However, not all OXA-48 variants possess significant activity toward carbapenems (e.g., OXA-163). Two
Serratia marcescens
isolates with resistance either to carbapenems or to extended-spectrum cephalosporins were successively recovered from the same patient. A genomic comparison using pulsed-field gel electrophoresis and automated Rep-PCR typing identified a 97.8% similarity between the two isolates. Both strains were resistant to penicillins and first-generation cephalosporins. The first isolate was susceptible to expanded-spectrum cephalosporins, was resistant to carbapenems, and had a significant carbapenemase activity (positive Carba NP test) related to the expression of OXA-48. The second isolate was resistant to expanded-spectrum cephalosporins, was susceptible to carbapenems, and did not express a significant imipenemase activity, (negative for the Carba NP test) despite possessing a
bla
OXA-48
-type gene. Sequencing identified a novel OXA-48-type β-lactamase, OXA-405, with a four-amino-acid deletion compared to OXA-48. The
bla
OXA-405
gene was located on a ca. 46-kb plasmid identical to the prototype IncL/M
bla
OXA-48
-carrying plasmid except for a ca. 16.4-kb deletion in the
tra
operon, leading to the suppression of self-conjugation properties. Biochemical analysis showed that OXA-405 has clavulanic acid-inhibited activity toward expanded-spectrum activity without significant imipenemase activity. This is the first identification of a successive switch of catalytic activity in OXA-48-like β-lactamases, suggesting their plasticity. Therefore, this report suggests that the first-line screening of carbapenemase producers in
Enterobacteriaceae
may be based on the biochemical detection of carbapenemase activity in clinical settings.
The Role of CD1d-Restricted NKT Cells in the Clearance of Pseudomonas aeruginosa from the Lung Is Dependent on the Host Genetic Background
Authors: Benoit Patrick , Sigounas Vaia Yioula , Thompson Jenna L. , van Rooijen Nico , Poynter Matthew E. , Wargo Matthew J. , Boyson Jonathan E. 
Published: April 2015

ABSTRACT

Pseudomonas aeruginosa
is an important human opportunistic pathogen, accounting for a significant fraction of hospital-acquired lung infections. CD1d-restricted NKT cells comprise an unusual innate-like T cell subset that plays important roles in both bacterial and viral infections. Previous reports have differed in their conclusions regarding the role of NKT cells in clearance of
P. aeruginosa
from the lung. Since there is significant strain-dependent variation in NKT cell number and function among different inbred strains of mice, we investigated whether the role of NKT cells was dependent on the host genetic background. We found that NKT cells did indeed play a critical role in the clearance of
P. aeruginosa
from the lungs of BALB/c mice but that they played no discernible role in clearance from the lungs of C57BL/6 mice. We found that the strain-dependent role of NKT cells was associated with significant strain-dependent differences in cytokine production by lung NKT cells and that impaired clearance of
P. aeruginosa
in BALB/c CD1d
−/−
mice was associated with an increase in neutrophil influx to the lung and increased levels of proinflammatory cytokines and chemokines after infection. Finally, we found that the role of alveolar macrophages was also dependent on the genetic background. These data provide further support for a model in which the unusually high level of variability in NKT cell number and function among different genetic backgrounds may be an important contributor to infectious-disease susceptibility and pathology.
Quorum Sensing Is Accompanied by Global Metabolic Changes in the Opportunistic Human Pathogen Pseudomonas aeruginosa
Authors: Davenport Peter W. , Griffin Julian L. , Welch Martin 
Published: April 2015

ABSTRACTPseudomonas aeruginosausesN-acyl-homoserine lactone (AHL)-dependent quorum sensing (QS) systems to control the expression of secreted effectors. These effectors can be crucial to the ecological fitness of the bacterium, playing roles in nutrient acquisition, microbial competition, and virulence. In this study, we investigated the metabolic consequences of AHL-dependent QS by monitoring the metabolic profile(s) of alasI rhlIdouble mutant (unable to make QS signaling molecules) and its wild-type progenitor as they progressed through the growth curve. Analysis of culture supernatants by1H-nuclear magnetic resonance (1H-NMR) spectroscopy revealed that at the point where AHL concentrations peaked in the wild type, the metabolic footprints (i.e., extracellular metabolites) of the wild-type andlasI rhlImutant diverged. Subsequent gas chromatography-mass spectrometry (GC-MS)-based analysis of the intracellular metabolome revealed QS-dependent perturbations in around one-third of all identified metabolites, including altered concentrations of tricarboxylic acid (TCA) cycle intermediates, amino acids, and fatty acids. Further targeted fatty acid methyl ester (FAME) GC-MS-based profiling of the cellular total fatty acid pools revealed that QS leads to changes associated with decreased membrane fluidity and higher chemical stability. However, not all of the changes we observed were necessarily a direct consequence of QS; liquid chromatography (LC)-MS analyses revealed that polyamine levels were elevated in thelasI rhlImutant, perhaps a response to the absence of QS-dependent adaptations. Our data suggest that QS leads to a global readjustment in central metabolism and provide new insight into the metabolic changes associated with QS during stationary-phase adaptation.IMPORTANCEQuorum sensing (QS) is a transcriptional regulatory mechanism that allows bacteria to coordinate their gene expression profile with the population cell density. The opportunistic human pathogenPseudomonas aeruginosauses QS to control the production of secreted virulence factors. In this study, we show that QS elicits a global “metabolic rewiring” inP. aeruginosa. This metabolic rerouting of fluxes is consistent with a variety of drivers, ranging from altered QS-dependent transcription of “metabolic genes” through to the effect(s) of global “metabolic readjustment” as a consequence of QS-dependent exoproduct synthesis, as well as a general stress response, among others. To our knowledge, this is the first study of its kind to assess the global impact of QS on the metabolome.
The Discrete and Semicontinuous Fréchet Distance with Shortcuts via Approximate Distance Counting and Selection
Authors: Avraham Rinat Ben , Filtser Omrit , Kaplan Haim , Katz Matthew J. , Sharir Micha 
Published: April 2015

The
Fréchet distance
is a well-studied similarity measure between curves. The
discrete Fréchet distance
is an analogous similarity measure, defined for two sequences of
m
and
n
points, where the points are usually sampled from input curves. We consider a variant, called the
discrete Fréchet distance with shortcuts
, which captures the similarity between (sampled) curves in the presence of outliers. When shortcuts are allowed only in one noise-containing curve, we give a randomized algorithm that runs in
O
((
m
+
n
)
6/5 + ε
) expected time, for any ε > 0. When shortcuts are allowed in both curves, we give an
O
((
m
2/3
n
2/3
+
m
+
n
)log
3
(
m
+
n
))-time deterministic algorithm.

We also consider the semicontinuous Fréchet distance with one-sided shortcuts, where we have a sequence of
m
points and a polygonal curve of
n
edges, and shortcuts are allowed only in the sequence. We show that this problem can be solved in randomized expected time
O
((
m
+
n
)
2/3
m
2/3
n
1/3
log (
m
+
n
)).

Our techniques are novel and may find further applications. One of the main new technical results is: Given two sets of points
A
and
B
in the plane and an interval
I
, we develop an algorithm that decides whether the number of pairs (
x
,
y
) ∈
A
×
B
whose distance dist(
x
,
y
) is in
I
is less than some given threshold
L
. The running time of this algorithm decreases as
L
increases. In case there are more than
L
pairs of points whose distance is in
I
, we can get a small sample of pairs that contain a pair at approximate median distance (i.e., we can approximately “bisect”
I
). We combine this procedure with additional ideas to search, with a small overhead, for the optimal one-sided Fréchet distance with shortcuts, using a very fast decision procedure. We also show how to apply this technique for approximating distance selection (with respect to rank), and a somewhat more involved variant of this technique is used in the solution of the semicontinuous Fréchet distance with one-sided shortcuts. In general, the new technique can be applied to optimization problems for which the decision procedure is very fast but standard techniques like parametric search makes the optimization algorithm substantially slower.
Oscillation Criteria of Third-Order Nonlinear Damped Dynamic Equations on Time Scales
Authors: Qiu Yang-Cong 
Published: April 2015

We establish oscillation criteria of third-order nonlinear damped dynamic equations on time scales of the formr1tr2txΔtγΔΔ+ft, xt,xσt, xgt, xΔt=0by employing functions in some function classes and the generalized Riccati transformation. Two examples are given to show the significance of the conclusions.
Mechanistic Rationale to Target PTEN-Deficient Tumor Cells with Inhibitors of the DNA Damage Response Kinase ATM
Authors: McCabe Nuala , Hanna Conor , Walker Steven M. , Gonda David , Li Jie , Wikstrom Katarina , Savage Kienan I. , Butterworth Karl T. , Chen Clark , Harkin D. Paul , Prise Kevin M. , Kennedy Richard D. 
Published: April 2015

Abstract
Ataxia telangiectasia mutated (ATM) is an important signaling molecule in the DNA damage response (DDR). ATM loss of function can produce a synthetic lethal phenotype in combination with tumor-associated mutations in FA/BRCA pathway components. In this study, we took an siRNA screening strategy to identify other tumor suppressors that, when inhibited, similarly sensitized cells to ATM inhibition. In this manner, we determined that PTEN and ATM were synthetically lethal when jointly inhibited. PTEN-deficient cells exhibited elevated levels of reactive oxygen species, increased endogenous DNA damage, and constitutive ATM activation. ATM inhibition caused catastrophic DNA damage, mitotic cell cycle arrest, and apoptosis specifically in PTEN-deficient cells in comparison with wild-type cells. Antioxidants abrogated the increase in DNA damage and ATM activation in PTEN-deficient cells, suggesting a requirement for oxidative DNA damage in the mechanism of cell death. Lastly, the ATM inhibitor KU-60019 was specifically toxic to PTEN mutant cancer cells in tumor xenografts and reversible by reintroduction of wild-type PTEN. Together, our results offer a mechanistic rationale for clinical evaluation of ATM inhibitors in PTEN-deficient tumors. Cancer Res; 75(11); 2159–65. ©2015 AACR.
Gestão de Serviços em Bibliotecas Públicas: aplicação do 5W2H na política de aquisição de acervo
Authors: Massaroni Iracema Fernandes , Scavarda Annibal José Roris Rodriguez 
Published: April 2015

<p>Apresenta o<strong> </strong>processo de aquisição de materiais informacionais que compõem o acervo das bibliotecas públicas, a gestão de serviços e a aplicação da ferramenta 5W2H sobre a aquisição do acervo, a utilização desta ferramenta permite a elaboração de um plano de ação proporcionando qualidade a gestão de serviços em bibliotecas públicas, evidenciando ainda o modelo das Bibliotecas Parque, tendo a Biblioteca Parque da Rocinha como laboratório deste estudo. Enfatizar que a biblioteca pública é uma instituição aberta, dinâmica, que através de seus serviços, atividades, funções, contribuem para o desenvolvimento educacional, cultural e social do individuo.</p>
Intermediate Outcomes in the Prospective, Multicenter Coarctation of the Aorta Stent Trial (COAST)
Authors: Meadows Jeffery , Minahan Matthew , McElhinney Doff B. , McEnaney Kerry , Ringel Richard 
Published: April 2015

Background—
The Coarctation of the Aorta Stent Trial (COAST) was designed to assess the safety and efficacy of the Cheatham Platinum stent when used in children and adults with native or recurrent coarctation. Acute outcomes have been reported. We report here follow-up to 2 years.

Methods and Results—
A total of 105 patients underwent attempted implantation, with 104 successes. There were no procedural deaths, serious adverse events, or surgical intervention. All patients experienced immediate reduction in upper- to lower-extremity blood pressure difference with sustained improvement to 2 years. Rates of hypertension and medication use decreased from baseline to 12 months and remained largely unchanged at 2 years. Six aortic aneurysms have been identified: 5 were successfully treated with covered stent placement, and 1 resolved without intervention. Stent fractures were noted in 2 patients at 1 year and 11 patients at 2 years, with evidence of fracture progression. To date, only larger stent diameter was associated with stent fracture. Twelve additional fractures have occurred after 2 years. No fracture has resulted in loss of stent integrity, stent embolization, aortic wall injury, or reobstruction. Nine reinterventions occurred in the first 2 years for stent redilation and address of aneurysms, and 10 additional reinterventions occurred after 2 years.

Conclusions—
The Cheatham Platinum stent is safe and associated with persistent relief of aortic obstruction. Stent fracture and progression of fracture occur but have not resulted in clinically important sequelae. Reintervention is common and related to early and late aortic wall injury and need for re-expansion of small-diameter stents.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00552812.
Has the Western Pacific Subtropical High Extended Westward since the Late 1970s?
Authors: Wu Liguang , Wang Chao 
Published: April 2015

Abstract
Previous studies reported that the summer western Pacific subtropical high (WPSH) has extended westward since the late 1970s and the change has affected summer rainfall over China and tropical cyclone prevailing tracks in the western North Pacific. The authors show that the 500-hPa geopotential height in the midlatitudes of the Northern Hemisphere has trended upward in the warming climate and the westward extension of the WPSH quantified with the 500-hPa geopotential height is mainly a manifestation of the global rising trend. That is, the summer 500-hPa WPSH has not remarkably extended westward since the late 1970s when the global trend is removed. It is suggested that the index that indicates the west–east shift of the summer 500-hPa WPSH should be redefined and that further investigation is needed to understand the observed climate change in the summer rainfall over China and tropical cyclone prevailing tracks in the western North Pacific.
Changes in Drought Characteristics over China Using the Standardized Precipitation Evapotranspiration Index
Authors: Chen Huopo , Sun Jianqi 
Published: April 2015

Abstract
The standardized precipitation evapotranspiration index (SPEI) is computed and compared in China using reference evapotranspiration calculated using the Thornthwaite (TH) approach and the Penman–Monteith (PM) equation. The analysis reveals that SPEI_PM outperforms the SPEI_TH with regard to drought monitoring during the period 1961–2012 over China, especially in arid regions of China. Furthermore, the SPEI_PM also performs better with regard to observed variations in soil moisture and streamflow in China. Thus, changes in drought characteristics over China are detected on the basis of variations in the SPEI_PM. The results indicate that droughts over China exhibit pronounced decadal variations over the past 50 yr, with more frequent and severe droughts occurring before the 1980s and in the 2000s compared with the 1980s and 1990s. Since the late 1990s, droughts have become more frequent and severe across China, especially in some regions of northern China. Concurrently, consecutive drought events have also increased across China. This suggests that dry conditions in China have been enhanced in recent years. Further analyses illustrate that the temperature and precipitation anomalies exhibit different roles in detecting droughts across China, which is primarily due to the magnitude of their variations and different climate variability. Considering temperature and precipitation perturbations, droughts exhibit relatively larger responses to temperature fluctuations in northern China and relatively larger responses to precipitation anomalies in southern China.
Socio-demographic differences in energy drink consumption and reasons for consumption among US college students
Authors: Poulos Natalie S , Pasch Keryn E 
Published: April 2015

Background: Energy drink consumption has become increasingly prevalent among US college students, yet little is known about current rates of consumption and reasons for consumption among current energy drink users, particularly differences related to gender and race/ethnicity. Objectives: To better understand energy drink consumption alone and mixed with alcohol among US undergraduate college students who currently use energy drinks. Methods: Participants included 330 energy drink users ( m age = 18.7; White = 48.5%; Women = 46.1%) and 229 energy drink mixed with alcohol users ( m age = 18.8; White = 51.5%; Women = 51.8%). Students completed an online survey, which measured energy drink consumption alone and energy drinks mixed with alcohol. Descriptive statistics and differences by race/ethnicity and gender are reported for patterns and reasons of use. Results: Among past year energy drink users, 64.9% consumed energy drinks in the past month and 38.5% consumed in the past week. The most common reasons for energy drink consumption alone included studying for an exam and taste. Among past year energy drink mixed with alcohol users, 31.9% consumed within the past month. The most common reasons to mix alcohol and energy drinks included taste and to hide the flavour of alcohol. Key findings include that young men consume energy drinks alone and mixed with alcohol more often than young women. Young men are more likely to report energy drink consumption in the past week and report reasons related to partying than young women, while non-White youth report reasons related to academic performance as compared to White youth. Conclusion: Consideration of patterns and reasons for energy drink consumption may help interventions to ensure appropriate behaviours are targeted and are relevant to the population.
Outcomes After Anterior Cruciate Ligament Reconstruction Using the Norwegian Knee Ligament Registry of 4691 Patients
Authors: LaPrade Christopher M. , Dornan Grant J. , Granan Lars-Petter , LaPrade Robert F. , Engebretsen Lars 
Published: April 2015

Background: While the effects of concurrent meniscal resection and anterior cruciate ligament reconstruction (ACLR) are known to decrease patient outcomes and increase the rate of osteoarthritis over the long term, overall short-term patient functional outcomes in a large cohort of patients are not well known. Purpose/Hypothesis: The purpose of this study was to compare the preoperative and 2-year postoperative Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale scores after ACLR with and without meniscal injury. The hypothesis was that, in comparison with an isolated ACLR, patients with a medial meniscal (MM) or lateral meniscal (LM) resection with an ACLR would have significantly decreased 2-year postoperative KOOS outcomes, while those with an ACLR with an MM or LM repair would be indistinguishable from isolated ACLR. Study Design: Cohort study; Level of evidence, 2. Methods: The Norwegian Knee Ligament Registry (NKLR) was used to evaluate outcomes for a total of 4691 patients with primary ACLR. The KOOS scoring system was used to evaluate patients on 5 subscales (Pain, Other Symptoms, Activities of Daily Life [ADL], Sport and Recreation Function, and Quality of Life [QoL]) at time of surgery and at 2-year postoperative follow-up. Patients with isolated ACLR and ACLR with LM repair, LM resection, MM repair, or MM resection were compared using multiple linear regression modeling. Results: Preoperatively, in comparison with isolated ACLR, patients who had an ACLR with either an MM repair or MM resection had significantly lower scores for all KOOS subscores, and LM repair had significantly decreased scores on the Other Symptoms, Pain, and ADL subscales. Postoperatively, in comparison with isolated ACLR, 2-year KOOS outcomes were not significantly different between patients with ACLR and LM repair, MM resection, or LM resection; however, those with MM repair had significantly lower scores on the Other Symptoms and QoL subscales. Conclusion: Patients with ACLR with meniscal resections do not exhibit decreased clinical outcomes at 2 years postoperatively. It is recommended that clinicians follow patients with ACLR and concurrent meniscal treatment for longer than 2 years postoperatively.
Mid-term Results of Oxford Phase 3 Unicompartmental Knee Arthroplasties at a Small-Volume Center
Authors: Miettinen S. S. A. , Torssonen S. K. , Miettinen H. J. A. , Soininvaara T. 
Published: April 2015

Background and Aims: Unicompartmental knee arthroplasty is considered as an alternative to total knee arthroplasty for patients who have osteoarthritis limited to the medial compartment of the knee. The aim of this retrospective study was to find out clinical and radiological outcomes and related complications using the Oxford phase 3 prosthesis at a small-volume center. Material and methods: In all, 95 Oxford unicompartmental knee arthroplasties (87 patients) were performed between 2000 and 2010 in North Karelia Central Hospital. Of these, five patients had undergone revision surgery. In all, 52 unicompartmental knee arthroplasties (46 patients) participated in this study. The mean age of patients was 61.4 years, and 78.2% of patients were females. Pain and function levels were evaluated by using the Knee Society score. Radiographic analyses were performed on preoperative and postoperative and follow-up radiographs. Results and Conclusions: The mean follow-up time was 6.5 years, and the Kaplan–Meier estimated 9-year implant survival rate was 88.9% (95% confidence interval = 78.7%–99.1%). The median Knee Society score of 77 (range: 18–93) at follow-up was considered good (range: 70–79). In this study, we found out that medial knee pain remains in 10% of unicompartmental knee arthroplasties several years after surgery, although the reason for the pain remained unclear. These mid-term results are promising, and good results can be achieved also at a small-volume center when strict patient selection is followed.