bluuebunny/crossref_metadata_2025_split huggingface dataset:
Revisiting the orogenic energy balance in the western Taiwan orogen with weak faults
Authors: Meade Brendan J. 
Published: December 2012

AbstractOrogens at convergent margins must meet the energetic requirements necessary to lift rocks against gravity, allow for frictional sliding along basal detachments and accommodate internal deformation processes. The combination of critical taper and kinematic wedge theories predicts the partitioning between these energy sinks as a function of both fault and crustal strengths. Integrating contemporary estimates of both crustal pore fluid pressures and the coefficient of friction on major faults, we find that work associated with internal deformation processes is the dominant energy sink in the western Taiwan orogenic wedge. These processes consume 54% of the total work budget, while the dissipation rates associated with frictional sliding on the basal detachment and lifting rocks against gravity are lower, requiring only 11% and 35% respectively. These results suggest a mechanical dichotomy in orogenic wedges where the faulting dominates the kinematic deformation budget, but internal distributed deformation processes dominate the energy budget.
Inorganic nitrogen release kinetics and exchangeable inorganic nitrogen of the sediments from shallow lakes in the middle and lower reaches of the Yangtze River region
Authors: Wang Shengrui , Jiao Lixin , Jin Xiangcan , Wang Juan 
Published: December 2012

AbstractInorganic nitrogen (IN) release kinetics and exchangeable inorganic nitrogen (EIN) of the sediments from shallow lakes in the middle and lower reaches of the Yangtze River region were investigated. The results showed that the EIN contents of the studied sediments ranged from 131 to 274 mg/kg. With the increase of the total nitrogen (TN) contents, their EIN also significantly increased. Their ratios of EIN to TN ranged from 5 to 17%, and with the increase of their TN contents, their ratios decreased. The relative contribution of NH4+‐N and NO3‐N to EIN ranged from 83 and 11% to 89 and 17%, respectively. The curves of the NO3‐N release kinetics of the studied sediments were not completely consistent with those of IN and NH4+‐N. The amounts of the IN released from sediments not only relate to their EIN contents, but also to other N fractions.
X‐ray acoustic computed tomography with pulsed x‐ray beam from a medical linear accelerator
Authors: Xiang Liangzhong , Han Bin , Carpenter Colin , Pratx Guillem , Kuang Yu , Xing Lei 
Published: December 2012

Purpose:The feasibility of medical imaging using a medical linear accelerator to generate acoustic waves is investigated. This modality, x‐ray acoustic computed tomography (XACT), has the potential to enable deeper tissue penetration in tissue than photoacoustic tomography via laser excitation.Methods:Short pulsed (μs‐range) 10 MV x‐ray beams with dose‐rate of approximately 30 Gy/min were generated from a medical linear accelerator. The acoustic signals were collected with an ultrasound transducer (500 KHz central frequency) positioned around an object. The transducer, driven by a computer‐controlled step motor to scan around the object, detected the resulting acoustic signals in the imaging plane at each scanning position. A pulse preamplifier, with a bandwidth of 20 KHz–2 MHz at −3 dB, and switchable gains of 40 and 60 dB, received the signals from the transducer and delivered the amplified signals to a secondary amplifier. The secondary amplifier had bandwidth of 20 KHz–30 MHz at −3 dB, and a gain range of 10–60 dB. Signals were recorded and averaged 128 times by an oscilloscope. A sampling rate of 100 MHz was used to record 2500 data points at each view angle. One set of data incorporated 200 positions as the receiver moved 360°. The x‐ray generated acoustic image was then reconstructed with the filtered back projection algorithm.Results:The x‐ray generated acoustic signals were detected from a lead rod embedded in a chicken breast tissue. The authors found that the acoustic signal was proportional to the x‐ray dose deposition, with a correlation of 0.998. The two‐dimensional XACT images of the lead rod embedded in chicken breast tissue were found to be in good agreement with the shape of the object.Conclusions:The first x‐ray acoustic computed tomography image is presented. The new modality may be useful for a number of applications, such as providing the location of a fiducial, or monitoring x‐ray dose distribution during radiation therapy. Although much work is needed to improve the image quality of XACT and to explore its performance in other irradiation energies, the benefits of this modality, as highlighted in this work, encourage further study.
New Life for an Old Drug: the Anthelmintic Drug Niclosamide Inhibits Pseudomonas aeruginosa Quorum Sensing
Authors: Imperi Francesco , Massai Francesco , Ramachandran Pillai Cejoice , Longo Francesca , Zennaro Elisabetta , Rampioni Giordano , Visca Paolo , Leoni Livia 
Published: December 2012

ABSTRACTThe need for novel antibacterial strategies and the awareness of the importance of quorum sensing (QS) in bacterial infections have stimulated research aimed at identifying QS inhibitors (QSIs). However, clinical application of QSIs identified so far is still distant, likely due to their unsuitability for use in humans. A promising way to overcome this problem is searching for anti-QS side activity among the thousands of drugs approved for clinical use in the treatment of different diseases. Here, we applied this strategy to the search for QSIs, by screening a library of FDA-approved compounds for their ability to inhibit the QS response in the Gram-negative pathogenPseudomonas aeruginosa. We found that the anthelmintic drug niclosamide strongly inhibits theP. aeruginosaQS response and production of acyl-homoserine lactone QS signal molecules. Microarray analysis showed that niclosamide affects the transcription of about 250 genes, with a high degree of target specificity toward the QS-dependent regulon. Phenotypic assays demonstrated that niclosamide suppresses surface motility and production of the secreted virulence factors elastase, pyocyanin, and rhamnolipids, and it reduces biofilm formation. In accordance with the strong antivirulence activity disclosedin vitro, niclosamide preventedP. aeruginosapathogenicity in an insect model of acute infection. Besides the finding that an FDA-approved drug has a promising antivirulence activity against one of the most antibiotic-resistant bacterial pathogens, this work provides a proof of concept that a lateral anti-QS activity can be detected among drugs already used in humans, validating a new approach to identify QSIs that could easily move into clinical applications.
Long-Term Risk for Readmission, Methicillin-Resistant Staphylococcus aureus (MRSA) Infection, and Death among MRSA-Colonized Veterans
Authors: Quezada Joaquin Nestor M. , Diekema Daniel J. , Perencevich Eli N. , Bailey George , Winokur Patricia L. , Schweizer Marin L. 
Published: December 2012

ABSTRACT

While numerous studies have assessed the outcomes of methicillin-resistant
S. aureus
(MRSA) colonization over the short term, little is known about longer-term outcomes after discharge. An assessment of long-term outcomes could provide information about the utility of various MRSA prevention approaches. A matched-cohort study was performed among Veterans Affairs (VA) patients screened for MRSA colonization between the years 2007 and 2009 and followed to evaluate outcomes until 2010. Cox proportional-hazard models were used to evaluate the association between MRSA colonization and long-term outcomes, such as infection-related readmission and crude mortality. A total of 404 veterans were included, 206 of whom were MRSA carriers and 198 of whom were noncarriers. There were no culture-proven MRSA infections on readmission among the noncarriers, but 13% of MRSA carriers were readmitted with culture-proven MRSA infections on readmission (
P
< 0.01). MRSA carriers were significantly more likely to be readmitted, to be readmitted more than once due to proven or probable MRSA infections, and to be readmitted within 90 days of discharge than noncarriers (
P
< 0.05). Infection-related readmission (adjusted hazard ratio [HR] = 4.07; 95% confidence interval [CI], 2.16 to 7.67) and mortality (adjusted HR = 2.71; 95% CI, 1.87 to 3.91) were significantly higher among MRSA carriers than among noncarriers after statistically adjusting for potential confounders. Among a cohort of VA patients, MRSA carriers are at high risk of infection-related readmission, MRSA infection, and mortality compared to noncarriers. Noncarriers are at very low risk of subsequent MRSA infection. Future studies should address whether interventions such as nasal or skin decolonization could result in improved outcomes for MRSA carriers.
Impact of Pharmacogenetic Markers ofCYP2B6, Clinical Factors, and Drug-Drug Interaction on Efavirenz Concentrations in HIV/Tuberculosis-Coinfected Patients
Authors: Manosuthi Weerawat , Sukasem Chonlaphat , Lueangniyomkul Aroon , Mankatitham Wiroj , Thongyen Supeda , Nilkamhang Samruay , Manosuthi Sukanya , Sungkanuparph Somnuek 
Published: December 2012

ABSTRACTComprehensive information on the effects of cytochrome P450 2B6 (CYP2B6) polymorphisms, clinical factors, and drug-drug interactions on efavirenz concentrations in HIV/tuberculosis-coinfected (HIV/TB) patients is unavailable. A total of 139 HIV/TB adults, 101 of whom received a rifampin-containing anti-TB regimen, were prospectively enrolled to receive efavirenz (600 mg)/tenofovir/lamivudine. Nine single nucleotide polymorphisms (SNPs) withinCYP2B6were genotyped. Plasma efavirenz concentrations were measured at 12 weeks. The median (interquartile range [IQR]) efavirenz concentration was 2.3 (1.4 to 3.9) mg/liter. The SNPs (frequencies of heterozygous and homozygous mutants) were 64C>T (10% and 1%), 499C>G (0% and 0%), 516G>T (47% and 8%), 785A>G (54% and 10%), 1375A>G (0% and 0%), 1459C>T (3% and 0%), 3003C>T (44% and 27%), 18492T>C (39% and 6%), and 21563C>T (57% and 5%). The four most frequentCYP2B6haplotypes identified were *1/*6 (41%), *1/*1 (35%), *1/*2 (7%), and *6/*6 (7%). The heterozygous/homozygous mutation associated with low efavirenz concentrations was 18492T>C (P< 0.001), and those associated with high efavirenz concentrations were 516G>T, 785A>G, and 21563C>T (allP< 0.05). Haplotype *1/*1 was associated with low efavirenz concentrations, and *6/*6, *1/*6, and *5/6 were associated with high efavirenz concentrations. As shown by multivariate analysis, low efavirenz concentrations were significantly associated with the *1/*1 haplotype (beta = −1.084,P= 0.027) and high body weight (beta = −0.076,P= 0.002). In conclusion, pharmacogenetic markers ofCYP2B6have the greatest impact with respect to inducing low plasma efavirenz concentrations in HIV/TB Thai patients.
The Genetic Environment of the
cfr
Gene and the Presence of Other Mechanisms Account for the Very High Linezolid Resistance of Staphylococcus epidermidis Isolate 426-3147L
Authors: LaMarre Jacqueline , Mendes Rodrigo E. , Szal Teresa , Schwarz Stefan , Jones Ronald N. , Mankin Alexander S. 
Published: December 2012

ABSTRACT

The clinical
Staphylococcus epidermidis
isolate 426-3147L exhibits an unusually high resistance to linezolid that exceeds 256 μg/ml. The presence of the
cfr
gene, encoding the RNA methyltransferase targeting an rRNA nucleotide located in the linezolid binding site, accounts for a significant fraction of resistance. The association of
cfr
with a multicopy plasmid is one of the factors that contribute to its elevated expression. Mapping of the
cfr
transcription start sites identified the native
cfr
promoter. Furthermore, analysis of the
cfr
transcripts in
Staphylococcus epidermidis
426-3147L showed that some of them originate from the upstream plasmid-derived promoters whose activity contributes to efficient
cfr
transcription. The genetic environment of the
cfr
gene and its idiosyncratic transcription pattern result in increased activity of Cfr methyltransferase, leading to a high fraction of the ribosomes being methylated at A2503 of the 23S rRNA. Curing of the
Staphylococcus epidermidis
426-3147L isolate from the
cfr
-containing plasmid reduced the linezolid MIC to 64 μg/ml, indicating that other determinants contribute to resistance. Nucleotide sequence analysis revealed the presence of the C2534T mutation in two of the six 23S rRNA gene alleles as well as the presence of mutations in the genes of ribosomal proteins L3 and L4, which were previously implicated in linezolid resistance. Thus, the combination of resistance mechanisms operating through alteration of the drug target site appears to cause an unusually high level of linezolid resistance in the isolate.
Linezolid Surveillance Results for the United States: LEADER Surveillance Program 2011
Authors: Flamm Robert K. , Mendes Rodrigo E. , Ross James E. , Sader Helio S. , Jones Ronald N. 
Published: December 2012

ABSTRACT

The LEADER surveillance program monitors the
in vitro
activity of linezolid and comparator agents against Gram-positive bacteria in the United States. In its eighth consecutive year (2011), a total of 60 medical centers from the United States, including seven medical centers specializing in children's health care contributed a total of 7,303 Gram-positive pathogens. The MIC
90
value for
Staphylococcus aureus
was 2 μg/ml, and for coagulase-negative staphylococci, enterococci,
Streptococcus pneumoniae
, β-hemolytic streptococci, and viridans group streptococci, the MIC
90
was 1 μg/ml. The “all organism” linezolid-resistant and nonsusceptible rate was only 0.19%.
The B Subunit of an AB5 Toxin Produced by Salmonella enterica Serovar Typhi Up-Regulates Chemokines, Cytokines, and Adhesion Molecules in Human Macrophage, Colonic Epithelial, and Brain Microvascular Endothelial Cell Lines
Authors: Wang Hui , Paton James C. , Herdman Brock P. , Rogers Trisha J. , Beddoe Travis , Paton Adrienne W. 
Published: December 2012

ABSTRACT

The principal function of bacterial AB5 toxin B subunits is to interact with glycan receptors on the surfaces of target cells and mediate the internalization of holotoxin. However, B subunit-receptor interactions also have the potential to impact cell signaling pathways and, in so doing, contribute to pathogenesis independently of the catalytic (toxic) A subunits. Various
Salmonella enterica
serovars, including
Salmonella enterica
serovar Typhi, encode an AB5 toxin (ArtAB), the A subunit of which is an ADP-ribosyltransferase related to the S1 subunit of pertussis toxin. However, although the A subunit is able to catalyze ADP-ribosylation of host G proteins, a cytotoxic phenotype has yet to be identified for the holotoxin. We therefore examined the capacity of the purified B subunit (ArtB) from
S
. Typhi to elicit cytokine, chemokine, and adhesion molecule responses in human macrophage (U937), colonic epithelial (HCT-8) cell, and brain microvascular endothelial cell (HBMEC) lines. Secretion of the chemokines monocyte chemotactic protein 1 (MCP-1) and interleukin 8 (IL-8) was increased in all three tested cell lines, with macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and granulocyte colony-stimulating factor (G-CSF) also significantly increased in U937 cells. ArtB also upregulated the cytokines tumor necrosis factor alpha (TNF-α) and IL-6 in HBMECs and HCT-8 cells, but not in U937 cells, while intercellular adhesion molecule 1 (ICAM-1) was upregulated in HCT-8 and U937 cells and vascular cell adhesion molecule 1 (VCAM-1) was upregulated in HBMECs. Thus, ArtB may contribute to pathogenesis independently of the A subunit by promoting and maintaining a strong inflammatory response at the site of infection.
Lipopolysaccharide-Deficient Acinetobacter baumannii Shows Altered Signaling through Host Toll-Like Receptors and Increased Susceptibility to the Host Antimicrobial Peptide LL-37
Authors: Moffatt Jennifer H. , Harper Marina , Mansell Ashley , Crane Bethany , Fitzsimons Timothy C. , Nation Roger L. , Li Jian , Adler Ben , Boyce John D. 
Published: December 2012

ABSTRACT

Infections caused by multidrug-resistant
Acinetobacter baumannii
have emerged as a serious global health problem. We have shown previously that
A. baumannii
can become resistant to the last-line antibiotic colistin via the loss of lipopolysaccharide (LPS), including the lipid A anchor, from the outer membrane (J. H. Moffatt, M. Harper, P. Harrison, J. D. Hale, E. Vinogradov, T. Seemann, R. Henry, B. Crane, F. St. Michael, A. D. Cox, B. Adler, R. L. Nation, J. Li, and J. D. Boyce, Antimicrob. Agents Chemother.
54:
4971–4977, 2010). Here, we show how these LPS-deficient bacteria interact with components of the host innate immune system. LPS-deficient
A. baumannii
stimulated 2- to 4-fold lower levels of NF-κB activation and tumor necrosis factor alpha (TNF-α) secretion from immortalized murine macrophages, but it still elicited low levels of TNF-α secretion via a Toll-like receptor 2-dependent mechanism. Furthermore, we show that while LPS-deficient
A. baumannii
was not altered in its resistance to human serum, it showed increased susceptibility to the human antimicrobial peptide LL-37. Thus, LPS-deficient, colistin-resistant
A. baumannii
shows significantly altered activation of the host innate immune inflammatory response.
Complicated urinary infection and extrapulmonary tuberculosis
Authors: Bacci Marcelo Rodrigues , Namura José Jorge , Lera Andrea Thaumaturgo 
Published: December 2012

Approximately 30% of the world population presents with tuberculosis. In developed countries, genitourinary manifestation is responsible for over 40% of extrapulmonary cases. Genitourinary tuberculosis is often diagnosed in the later stage due to the fact that the symptoms are non-specific and technical difficulties to isolate the tubercle bacillus through bacilloscopy or culture in specific medium are many. We present a case of a 47-year-old African-American woman with relapsing urinary infection and sterile pyuria. After a 4 four-year evolution, the patient developed functional exclusion of the right kidney as a consequence of chronic pyelonephritis. The investigation result for alcohol-acid bacillus resistant in urine was positive along with the culture forMycobacterium tuberculosis.
One-pot synthesis of dihydrobenzisoxazoles from hydroxylamines, acetylenedicarboxylates, and arynes via in situ generation of nitrones
Authors: Li Pan , Wu Chunrui , Zhao Jingjing , Li Yang , Xue Weichao , Shi Feng 
Published: December 2012

Aryne [3 + 2] cycloaddition with nitrones generated in situ from the addition of hydroxylamines to acetylenedicarboxylates affords moderate to good yields of dihydrobenzisoxazoles. This reaction extends the current scope of aryne cycloaddition to include in situ generated nitrones and produces functionalized dihydrobenzisoxazoles with a quaternary center.
Genetic Loci for Coronary Calcification and Serum Lipids Relate to Aortic and Carotid Calcification
Authors: Bos Daniel , Ikram M. Arfan , Isaacs Aaron , Verhaaren Benjamin F.J. , Hofman Albert , van Duijn Cornelia M. , Witteman Jacqueline C.M. , van der Lugt Aad , Vernooij Meike W. 
Published: December 2012

Background—
Atherosclerosis in different vessel beds shares lifestyle and environmental risk factors. It is unclear whether this holds for genetic risk factors. Hence, for the current study genetic loci for coronary artery calcification and serum lipid levels, one of the strongest risk factors for atherosclerosis, were used to assess their relation with atherosclerosis in different vessel beds.

Methods and Results—
From 1987 persons of the population-based Rotterdam Study, 3 single-nucleotide polymorphisms (SNPs) for coronary artery calcification and 132 SNPs for total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglycerides were used. To quantify atherosclerotic calcification as a marker of atherosclerosis, all participants underwent nonenhanced computed tomography of the aortic arch and carotid arteries. Associations between genetic risk scores of the joint effect of the SNPs and of all calcification were investigated. The joint effect of coronary artery calcification–SNPs was associated with larger calcification volumes in all vessel beds (difference in calcification volume per SD increase in genetic risk score: 0.15 [95% confidence interval, 0.11–0.20] in aorta, 0.14 [95% confidence interval, 0.10–0.18] in extracranial carotids, and 0.11 [95% confidence interval, 0.07–0.16] in intracranial carotids). The joint effect of total cholesterol SNPs, low-density lipoprotein SNPs, and of all lipid SNPs together was associated with larger calcification volumes in both the aortic arch and the carotid arteries but attenuated after adjusting for the lipid fraction and lipid-lowering medication.

Conclusions—
The genetic basis for aortic arch and carotid artery calcification overlaps with the most important loci of coronary artery calcification. Furthermore, serum lipids share a genetic predisposition with both calcification in the aortic arch and the carotid arteries, providing novel insights into the cause of atherosclerosis.
Protecting the Self: The Effect of Social-evaluative Threat on Neural Representations of Self
Authors: Hughes Brent L. , Beer Jennifer S. 
Published: December 2012

Abstract
One of the most robust ways that people protect themselves from social-evaluative threat is by emphasizing the desirability of their personal characteristics, yet the neural underpinnings of this fundamental process are unknown. The current fMRI study addresses this question by examining self-evaluations of desirability (in comparison with other people) as a response to threat. Participants judged how much personality traits described themselves in comparison with their average peer. These judgments were preceded by threatening or nonthreatening social-evaluative feedback. Self-evaluations made in response to threat significantly increased activation in a number of regions including the OFC, medial pFC, lateral pFC, amygdala, and insula. Individual differences in the extent to which threat increased desirability were significantly correlated with medial OFC activity. This is the first study to examine the neural associations of a fundamental self-protection strategy: responding to threat by emphasizing the self's desirability. Although neural research has separately examined self-evaluation processes from the regulation of social-evaluative threat, little is known about the interplay between the two. The findings build on this previous research by showing that regions, often associated with self-evaluation, are modulated by the degree to which people respond to threat by emphasizing their own desirability.