bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decoupled genomic elements and the evolution of partner quality in nitrogen‐fixing rhizobia
Authors: Gordon Benjamin R. , Klinger Christie R. , Weese Dylan J. , Lau Jennifer A. , Burke Patricia V. , Dentinger Bryn T. M. , Heath Katy D. 
Published: January 2016

AbstractUnderstanding how mutualisms evolve in response to a changing environment will be critical for predicting the long‐term impacts of global changes, such as increased N (nitrogen) deposition. Bacterial mutualists in particular might evolve quickly, thanks to short generation times and the potential for independent evolution of plasmids through recombination and/or HGT (horizontal gene transfer). In a previous work using the legume/rhizobia mutualism, we demonstrated that long‐term nitrogen fertilization caused the evolution of less‐mutualistic rhizobia. Here, we use our 63 previously isolated rhizobium strains in comparative phylogenetic and quantitative genetic analyses to determine the degree to which variation in partner quality is attributable to phylogenetic relationships among strains versus recent genetic changes in response to N fertilization. We find evidence of distinct evolutionary relationships between chromosomal and pSym genes, and broad similarity between pSym genes. We also find that nifD has a unique evolutionary history that explains much of the variation in partner quality, and suggest MoFe subunit interaction sites in the evolution of less‐mutualistic rhizobia. These results provide insight into the mechanisms behind the evolutionary response of rhizobia to long‐term N fertilization, and we discuss the implications of our results for the evolution of the mutualism.
Nesiritide in patients hospitalized for acute heart failure: does timing matter? Implication for future acute heart failure trials
Authors: Wong Yee Weng , Mentz Robert J. , Felker G.Michael , Ezekowitz Justin , Pieper Karen , Heizer Gretchen , Hasselblad Vic , Metra Marco , O'Connor Christopher M. , Armstrong Paul W. , Starling Randall C. , Hernandez Adrian F. 
Published: January 2016

AimsIt remains unclear if early administration of i.v. nesiritide in patients hospitalized with acute heart failure (AHF) is associated with improved clinical outcomes.Methods and resultsWe analysed data from 7007 patients enrolled in ASCEND‐HF to examine the associations between time to treatment with study medication (nesiritide or placebo) and clinical endpoints: (i) moderate to marked dyspnoea relief on a 7‐point Likert scale at 6 h; (ii) 30‐day all‐cause mortality or re‐hospitalization; and (iii) 30‐day all‐cause mortality. The median time to study drug administration was 16.7 h (25th, 75th percentiles = 6.5, 23.1), with significant regional variation (e.g. median of 13.0 h in Asia‐Pacific vs. 18.4 h in North America). After risk adjustment, each hour delay in study medication after the first 10 h from initial hospital presentation was associated with modestly reduced odds of dyspnoea relief [(adjusted odds ratio (OR) 0.98, 95% confidence interval (CI) 0.98–0.99; P < 0.0001]. Every hour delay in study medication was associated with modestly higher all‐cause mortality or re‐hospitalization (unadjusted OR 1.01, 95% CI 1.01–1.02; P < 0.001) due to pre‐randomization therapies and known predictors of 30‐day outcomes (adjusted P = 0.12). There was no significant association between time to study drug and all‐cause mortality (P > 0.08).ConclusionIn a large international AHF trial, time to treatment with study medication varied markedly across regions. Earlier administration of study medication was associated with modestly better dyspnoea relief, but not 30‐day clinical outcomes. The association between timing of treatment with study medication and study endpoints may have implications for the interpretation of AHF studies and future trial design.
Selective organic carbon losses from soils by sheet erosion and main controls
Authors: Müller‐Nedebock Daniel , Chivenge Pauline , Chaplot Vincent 
Published: January 2016

AbstractAlthough the impact of sheet erosion on the selective transportation of mineral soil particles has been widely investigated, little is yet known about the specific mechanisms of organic carbon (OC) erosion, which constitutes an important link in the global carbon cycle. The present study was conducted to quantify the impact of sheet erosion on OC losses from soils. Erosion plots with the lengths of 1‐ and 5‐m were installed at different topographic positions along a hillslope in a mountainous South African region. A total of 32 rainfall events from a three years period (November 2010 up to February 2013), were studied and evaluated for runoff (R), particulate and dissolved organic carbon (POCL and DOCL). In comparison to the 0–0·05 m bulk soil, the sediments from the 1‐m plots were enriched in OC by a factor 2·6 and those from the 5‐m long plots by a factor of 2·2, respectively. These findings suggest a preferential erosion of OC. In addition, total organic carbon losses (TOCL) were incurred mainly in particulate form (~94%) and the increase in TOCL from 14·09 ± 0·68 g C m−1 yr−1 on 1‐m plots to 50·03 ± 2·89 g C m−1 yr−1 on 5‐m plots illustrated an increase in sheet erosion efficiency with increasing slope length. Both TOCL and sediment enrichment in OC correspondingly increased with a decrease in soil basal grass cover. The characteristics of rainstorms had no significant impact on the selectivity of OC erosion. The results accrued in this study investigating the links between sheet erosion and OC losses, are expected to be of future value in the generation of carbon specific erosion models, which can further help to inform and improve climate change mitigation measures. Copyright © 2016 John Wiley & Sons, Ltd.
Sex differences in amygdala shape: Insights from Turner syndrome
Authors: Green Tamar , Fierro Kyle C. , Raman Mira M. , Foland‐Ross Lara , Hong David S. , Reiss Allan L. 
Published: January 2016

AbstractObjectiveSex differences in the manifestation of psychiatric disorders, including anxiety disorders, are among the most prominent findings in psychiatry. The study of Turner syndrome (TS), caused by X‐monosomy, has the potential to reveal mechanisms that underline male/female differences in neuropsychiatric disorders. The amygdala has been implicated in numerous neuropsychiatric disorders. Previous studies suggest an effect of TS on amygdala volume as well as on amygdala‐related behaviors such as anxiety. Our objective is to investigate the amygdala shape in TS. Specifically, we tested whether amygdala enlargements in TS are localized to specific nuclei implicated in anxiety, such as the basomedial nucleus.Experimental design: We use a surface‐based analytical modeling approach to contrast 41 pre‐estrogen treatment girls with TS (mean age 8.6 ± 2.4) with 34 age‐and sex‐matched typically developing (TD) controls (mean age 8.0 ± 2.8). Anxiety symptoms were assessed using the Revised Children's Manifest Anxiety Scale ‐ 2 (RCMAS‐2) in both groups.Principal observations: TS was associated with anomalous enlargement of the amygdala. Surface‐based modeling revealed shape differences (increased radial‐distances) in bilateral basal and basomedial nuclei within the basolateral complex. RCMAS‐2 Total Anxiety t‐score was significantly higher in participants with TS compared with TD controls (P = 0.012).ConclusionsGroup differences in global amygdala volumes were driven by local morphological increases in areas that are critically involved in face emotion processing and anxiety. In the context of increased amygdala volumes in TS, our results also showed increased worry and social anxiety in young girls with TS compared with TD. Hum Brain Mapp 37:1593‐1601, 2016. © 2016 Wiley Periodicals, Inc.
Numerical Simulation of Soil Water Dynamics Under Stationary Sprinkler Irrigation With Mohid‐Land
Authors: Simionesei Lucian , Ramos Tiago B. , Brito David , Jauch Eduardo , Leitão Pedro C. , Almeida Carina , Neves Ramiro 
Published: January 2016

AbstractWater distribution in sprinkler irrigation systems remains one of the most challenging problems in irrigation water management. Due to lack of water distribution uniformity, parts of a field may be over‐irrigated while others may be under‐irrigated, thus affecting root water and nutrient uptake and crop yield. The objective of this paper was to show the capabilities of the MOHID‐Land model in simulating soil water dynamics and maize growth under a stationary sprinkler irrigation system with low water distribution uniformity (56%). A 3D simulation domain (28 × 26 × 1 m) was defined to consider different water application rates at the soil surface and the variability of the soil hydraulic properties (two soil types). The model was able to take into account the effect of water distribution and soil variability on soil water content and fluxes, root water uptake reductions due to water stress, soil evaporation, leaf area index and total dry biomass. The resulting soil water balance revealed that irrigation inputs were lower (329 mm) than those theoretically defined to fulfil crop water requirements when the variable‐rate application of water was not considered (540 mm). Consequently, the range of variation of soil water stress in the simulation domain was relatively large (between 1 and 64%). MOHID‐Land has thus the potential of becoming an important tool for precision irrigation by focusing on site‐specific irrigation and crop management rather than the current field unit approach. Copyright © 2016 John Wiley & Sons, Ltd.
Microarchitecture and Peripheral BMD are Impaired in Postmenopausal White Women With Fracture Independently of Total HipT-Score: An International Multicenter Study
Authors: Boutroy Stephanie , Khosla Sundeep , Sornay-Rendu Elisabeth , Zanchetta Maria Belen , McMahon Donald J , Zhang Chiyuan A , Chapurlat Roland D , Zanchetta Jose , Stein Emily M , Bogado Cesar , Majumdar Sharmila , Burghardt Andrew J , Shane Elizabeth 
Published: January 2016

ABSTRACT Because single-center studies have reported conflicting associations between microarchitecture and fracture prevalence, we included high-resolution peripheral quantitative computed tomography (HR-pQCT) data from five centers worldwide into a large multicenter analysis of postmenopausal women with and without fracture. Volumetric BMD (vBMD) and microarchitecture were assessed at the distal radius and tibia in 1379 white postmenopausal women (age 67 ± 8 years); 470 (34%) had at least one fracture including 349 with a major fragility fracture. Age, height, weight, and total hip T-score differed across centers and were employed as covariates in analyses. Women with fracture had higher BMI, were older, and had lower total hip T-score, but lumbar spine T-score was similar between groups. At the radius, total and trabecular vBMD and cortical thickness were significantly lower in fractured women in three out of five centers, and trabecular number in two centers. Similar results were found at the tibia. When data from five centers were combined, however, women with fracture had significantly lower total, trabecular, and cortical vBMD (2% to 7%), lower trabecular number (4% to 5%), and thinner cortices (5% to 6%) than women without fracture after adjustment for covariates. Results were similar at the radius and tibia. Similar results were observed with analysis restricted to major fragility fracture, vertebral and hip fractures, and peripheral fracture (at the radius). When focusing on osteopenic women, each SD decrease of total and trabecular vBMD was associated with a significantly increased risk of major fragility fracture (OR = 1.55 to 1.88, p &lt; 0.01) after adjustment for covariates. Moreover, trabecular architecture modestly improved fracture discrimination beyond peripheral total vBMD. In conclusion, we observed differences by center in the magnitude of fracture/nonfracture differences at both the distal radius and tibia. However, when data were pooled across centers and the sample size increased, we observed significant and consistent deficits in vBMD and microarchitecture independent of total hip T-score in all postmenopausal white women with fracture and in the subgroup of osteopenic women, compared to women who never had a fracture. © 2016 American Society for Bone and Mineral Research.
Sunitinib treatment reduces tumor growth and limits changes in microvascular properties after minor surgical intervention in an in vivo model of secondary breast cancer growth in bone
Authors: Schroeder Malte , Viezens Lennart , Wellbrock Jasmin , Fiedler Walter , Rüther Wolfgang , Algenstaedt Petra , Hansen‐Algenstaedt Nils , Schaefer Christian 
Published: January 2016

Background and ObjectivesSurgical interventions can alter the balance between pro‐ and anti‐angiogenic growth factors and thereby modulate tumor growth. Since the microcirculatory properties of tumors underlie organ‐specific differences, the microhemodynamic characteristics of bone metastasis have not yet been fully described. Angiogenesis inhibitors are increasingly being used to treat advanced stages of cancer. We hypothesized that the anti‐angiogenic drug sunitinib abrogates alterations in microvascular properties following a minor surgical intervention in an in vivo model of secondary breast cancer growth in the bone.MethodsIntravital microscopy was performed over 25 days using a xenograft model of breast cancer tumor growth in the bone to determine changes in microvascular properties during sunitinib treatment. Mastectomy was performed on day 5 to evaluate the effect of a minor surgical trauma on tumor growth and microvascular properties.ResultsAnti‐angiogenic therapy resulted in reduced tumor growth, decreased vascular density, and increased vascular diameters. Blood flow velocity remained constant while microvascular permeability temporarily increased after the surgical intervention.ConclusionsAdministration of sunitinib reduced tumor growth and altered microcirculatory properties in a time‐dependent manner. The observed dramatic increase in microvascular permeability after the surgical intervention may have implications for local tumor growth, and metastatic dissemination. J. Surg. Oncol. 2016;113:515–521. © 2016 Wiley Periodicals, Inc.
Effects of norspermidine on Pseudomonas aeruginosa biofilm formation and eradication
Authors: Qu Lin , She Pengfei , Wang Yangxia , Liu Fengxia , Zhang Di , Chen Lihua , Luo Zhen , Xu Huan , Qi Yong , Wu Yong 
Published: January 2016

AbstractBiofilms are defined as aggregation of single cell microorganisms and associated with over 80% of all the microbial infections. Pseudomonas aeruginosa is a Gram‐negative opportunistic pathogen capable of leading to various infections in immunocompromised people. Recent studies showed that norspermidine, a kind of polyamine, prevented and disrupted biofilm formation by some Gram‐negative bacterium. In this study, the effects of norspermidine on P. aeruginosa biofilm formation and eradication were tested. Microtiter plate combined with crystal violet staining was used to study the effects of norspermidine on P. aeruginosa initial attachment, then we employed SEM (scanning electron microscope), qRT‐PCR, and QS‐related virulence factor assays to investigate how norspermidine prevent biofilm formation by P. aeruginosa. We reported that high‐dose norspermidine had bactericide effect on P. aeruginosa, and norspermidine began to inhibit biofilm formation and eradicate 24‐h mature biofilm at concentration of 0.1 and 1 mmol/L, respectively, probably by preventing cell‐surface attachment, inhibiting swimming motility, and downregulating QS‐related genes expression. To investigate the potential utility of norspermidine in preventing device‐related infections, we found that catheters immersed with norspermidine were effective in eradicating mature biofilm. These results suggest that norspermidine could be a potent antibiofilm agent for formulating strategies against P. aeruginosa biofilm.
Modelling landslides in unsaturated slopes subjected to rainfall infiltration using material point method
Authors: Bandara Samila , Ferrari Alessio , Laloui Lyesse 
Published: January 2016

SummaryThis paper presents a dynamic fully coupled formulation for saturated and unsaturated soils that undergo large deformations based on material point method. Governing equations are applied to porous material while considering it as a continuum in which the pores of the solid skeleton are filled with water and air. The accuracy of the developed method is tested with available experimental and numerical results. The developed method has been applied to investigate the failure and post‐failure behaviour of rapid landslides in unsaturated slopes subjected to rainfall infiltration using two different bedrock geometries that lie below the top soil. The models show different failure and post‐failure mechanisms depending on the bedrock geometry and highlight the negative effects of continuous rain infiltrations. Copyright © 2016 John Wiley & Sons, Ltd.
Assessment of cortical damage in early multiple sclerosis with quantitative T2 relaxometry
Authors: Gracien René‐Maxime , Reitz Sarah C. , Hof Stephanie‐Michelle , Fleischer Vinzenz , Zimmermann Hilga , Droby Amgad , Steinmetz Helmuth , Zipp Frauke , Deichmann Ralf , Klein Johannes C. 
Published: January 2016

T2 relaxation time is a quantitative MRI in vivo surrogate of cerebral tissue damage in multiple sclerosis (MS) patients. Cortical T2 prolongation is a known feature in later disease stages, but has not been demonstrated in the cortical normal appearing gray matter (NAGM) in early MS.This study centers on the quantitative evaluation of the tissue parameter T2 in cortical NAGM in a collective of early MS and clinically isolated syndrome (CIS) patients, hypothesizing that T2 prolongation is already present at early disease stages and variable over space, in line with global and focal inflammatory processes in MS. Additionally, magnetization transfer ratio (MTR) mapping was performed for further characterization of the expected cortical T2 alteration.Quantitative T2 and MTR maps were acquired from 12 patients with CIS and early MS, and 12 matched healthy controls. The lesion‐free part of the cortical volume was identified, and the mean T2 and MTR values and their standard deviations within the cortical volume were determined. For evaluation of spatial specificity, cortical lobar subregions were tested separately for differences of mean T2 and T2 standard deviation.We detected significantly prolonged T2 in cortical NAGM in patients. T2 prolongation was found across the whole cerebral cortex and in all individual lobar subregions. Significantly higher standard deviations across the respective region of interest were found for the whole cerebral cortex and all subregions, suggesting the occurrence of spatially inhomogeneous cortical damage in all regions studied. A trend was observed for MTR reduction and increased MTR variability across the whole cortex in the MS group, suggesting demyelination.In conclusion, our results suggest that cortical damage in early MS is evidenced by spatially inhomogeneous T2 prolongation which goes beyond demyelination. Iron deposition, which is known to decrease T2, seems less prominent. Copyright © 2016 John Wiley & Sons, Ltd.
Spatial proximity statistics suggest a regulatory role of protein phosphorylation on compound binding
Authors: Korkuć Paula , Walther Dirk 
Published: January 2016

ABSTRACTPhosphorylation is an important post‐translational modification that regulates protein function by the attachment of negatively charged phosphate groups to phosphorylatable amino acid residues. As a mode of action, an influence of phosphorylation on the binding of compounds to proteins has been discussed and described for a number of proteins in the literature. However, a systematic statistical survey probing for enriched phosphorylation sites close to compound binding sites in support of this notion and with properly chosen random reference distributions has not been presented yet. Using high‐resolution protein structures from the Protein Data Bank including their co‐crystallized non‐covalently bound compounds and experimentally determined phosphorylation sites, we analyzed the pairwise distance distributions of phosphorylation and compound binding sites on protein surfaces. We found that phosphorylation sites are indeed located at significantly closer distances to compounds than expected by chance holding true specifically also for the subset of compound binding sites serving as catalytic sites of metabolic reactions. This tendency was particularly evident when treating phosphorylation sites as collective sets supporting the relevance of phosphorylation hotspots. Interestingly, phosphorylation sites were found to be closer to negatively charged than to positively charged compounds suggesting a stronger modulation of the binding of negatively charged compounds in dependence on phosphorylation status than on positively charged compounds. The enrichment of phosphorylation sites near compound binding sites confirms a regulatory role of phosphorylation in compound binding and provides a solid statistical basis for the literature‐reported selected events. Proteins 2016; 84:565–579. © 2016 Wiley Periodicals, Inc.
Can Economic Performance Predict Pediatric Surgical Capacity in Sub‐Saharan Africa?
Authors: Okoye Mekam T. , Nguyen Evelyn T. , Kushner Adam L. , Ameh Emmanuel A. , Nwomeh Benedict C. 
Published: January 2016

AbstractBackground
The relationship between economic status and pediatric surgical capacity in low‐ and middle‐income countries (LMICs) is poorly understood. In sub‐Saharan Africa (SSA), Nigeria accounts for 20 % of the population and has the highest Gross Domestic Product (GDP), but whether this economic advantage translates to increased pediatric surgical capacity is unknown. This study compares the pediatric surgical capacity between Nigeria and other countries within the region.MethodsThe Pediatric Personnel, Infrastructure, Procedures, Equipment and Supplies (PediPIPES) survey, a recent tool that is useful in assessing and comparing the capacity of health facilities to deliver essential and emergency surgical care (EESC) to children in LMICs, was used for this evaluation.ResultsData from hospitals in Nigeria (n = 24) and hospitals in 17 other sub‐Saharan African countries (n = 25) were compared. The GDP of Nigeria was approximately twenty‐five times the average GDP of the 17 other countries represented in our survey. Running water was unavailable in 58 % of the hospitals in Nigeria compared to 20 % of the hospitals in the other countries. Most hospitals in Nigeria and in the other countries did not have a CT scan (67 and 60 %, respectively). Endoscopes were unavailable in 58 % of the hospitals in Nigeria and 44 % of the hospitals in the other countries.ConclusionsDespite better economic indicators in Nigeria, there were no distinct advantages over the other countries in the ability to deliver EESC to children. Our findings highlighted the urgent need for specific allocation of more resources to pediatric surgical capacity building efforts across the entire region.