bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of aspirin in vascular surgery in patients from a randomized clinical trial (POISE-2)
Authors: Biccard B M , Sigamani A , Chan M T V , Sessler D I , Kurz A , Tittley J G , Rapanos T , Harlock J , Szalay D , Tiboni M E , Popova E , Vásquez S M , Kabon B , Amir M , Mrkobrada M , Mehra B R , El Beheiry H , Mata E , Tena B , Sabaté S , Zainal Abidin M K , Shah V R , Balasubramanian K , Devereaux P J 
Published: July 2018

Abstract

Background
In the POISE-2 (PeriOperative ISchemic Evaluation 2) trial, perioperative aspirin did not reduce cardiovascular events, but increased major bleeding. There remains uncertainty regarding the effect of perioperative aspirin in patients undergoing vascular surgery. The aim of this substudy was to determine whether there is a subgroup effect of initiating or continuing aspirin in patients undergoing vascular surgery.

Methods
POISE-2 was a blinded, randomized trial of patients having non-cardiac surgery. Patients were assigned to perioperative aspirin or placebo. The primary outcome was a composite of death or myocardial infarction at 30 days. Secondary outcomes included: vascular occlusive complications (a composite of amputation and peripheral arterial thrombosis) and major or life-threatening bleeding.

Results
Of 10 010 patients in POISE-2, 603 underwent vascular surgery, 319 in the continuation and 284 in the initiation stratum. Some 272 patients had vascular surgery for occlusive disease and 265 had aneurysm surgery. The primary outcome occurred in 13·7 per cent of patients having aneurysm repair allocated to aspirin and 9·0 per cent who had placebo (hazard ratio (HR) 1·48, 95 per cent c.i. 0·71 to 3·09). Among patients who had surgery for occlusive vascular disease, 15·8 per cent allocated to aspirin and 13·6 per cent on placebo had the primary outcome (HR 1·16, 0·62 to 2·17). There was no interaction with the primary outcome for type of surgery (P = 0·294) or aspirin stratum (P = 0·623). There was no interaction for vascular occlusive complications (P = 0·413) or bleeding (P = 0·900) for vascular compared with non-vascular surgery.

Conclusion
This study suggests that the overall POISE-2 results apply to vascular surgery. Perioperative withdrawal of chronic aspirin therapy did not increase cardiovascular or vascular occlusive complications. Registration number: NCT01082874 (http://www.clinicaltrials.gov).
A 3‐year experience of a simple, novel technique for accurate ostial/non‐ostial coronary stenting: The buddy balloon anchor stent technique
Authors: Chen G. C. , Lu X. M. , Song Y. M. , Gyawail Laxman , Geng Z. H. , Song M. B. , Qian D. H. , Zhang Y. P. , Ni D. C. , He Yun 
Published: July 2018

AbstractObjectiveTo evaluate the safety and efficacy of a new technique for accurate ostial/non‐ostial coronary stenting in percutaneous coronary intervention (PCI).BackgroundAccurate stent localization is a key factor impacting the postoperative success of patients undergoing PCI. However, the accurate localization of some lesions, especially ostial lesions, is very difficult to achieve, because they are often complicated by bobbing or to‐and‐fro movement of the stent during cardiac contractions.MethodsWe report a novel technique of precise ostial/non‐ostial stenting based on the buddy balloon anchor stent (BBAS) technique. Between May 2014 and July 2017, 47 patients with significant ostial/non‐ostial coronary stenosis that required accurate stenting were included in this study. Of them, 23 patients were treated using the conventional method and the remaining 24 patients were treated using (BBAS) technique. Evaluation was then performed using intravascular ultrasound (IVUS) in the procedural, or coronary computed tomography angiography (CCTA) in the follow up.ResultsUsing the BBAS technique, the procedural success was achieved in all 24 (100%) cases. IVUS was performed in seven patients (29.17%) and no procedural complications occurred. All six failed cases that occurred among patients with right coronary artery and left anterior descending artery ostial stenosis treated using the conventional method, the lesions were subsequently successfully re‐stented using the BBAS technique. After a follow‐up of 3–36 months, CCTA was performed in 11 patients (45.83%), all the stents were in the accurate position. There were no major cardiovascular events of death, myocardial infarction, or target lesion revascularization.ConclusionBBAS is a simple, highly successful and safe technique for accurate stenting of difficult ostial/nonostial coronary stenosis lesions.
Slope of left ventricular filling as an index of valvular and paravalvular regurgitation in native and prosthetic aortic valves
Authors: Makki Nader , Ghao Xu , Whitson Bryan , Shreenivas Satya , Crestanello Juan , Lilly Scott 
Published: July 2018

AbstractBackgroundPrecise quantification of paravalvular aortic regurgitation (PAR) is challenging. Aortic regurgitation index (AR index) has been validated in transcatheter aortic valve replacement (TAVR) cohorts; however, accuracy is limited by heart rate dependency. Diastolic pressure time (DPT) index has been suggested as an alternative and also predicts mortality after TAVR. We chose to evaluate the left ventricular diastolic filling slope (LVDFS) as a surrogate of AR, and suggest it is less heart rate dependent than the AR index and comparable to DPT index.MethodsFor initial validation, we compared the LVDFS between three cohorts of patients with native aortic valves referred for hemodynamic assessment: (1) Patients without AR; (2) moderate AR; and (3) severe AR. We then retrospectively identified TAVR patients between January 2012 and 2017, and compared LVDFS to echocardiographic PAR.ResultsIn both TAVR patients and those patients with native aortic valve disease, the LVDFS showed a stepwise increase with increasing echocardiographic AR severity. When compared to AR or DPT indices, LVDFS better discriminated the degree of AR in native valves and post‐TAVR when AR is primarily paravalvular. Additionally, the slope did not considerably change across a spectrum of heart rates in both native and post‐TAVR populations.ConclusionsThe LVDFS is a simple, reproducible metric that can be operationalized in patients undergoing TAVR, as well as those with native valve regurgitation. Additional studies are necessary to determine the relationship between LVDFS and post‐TAVR outcomes.
Long‐term outcomes after treatment of bare‐metal stent restenosis with paclitaxel‐coated balloon catheters or everolimus‐eluting stents: 3‐year follow‐up of the TIS clinical study
Authors: Pleva Leos , Kukla Pavel , Zapletalova Jana , Hlinomaz Ota 
Published: July 2018

AbstractBackgroundThe efficacy of paclitaxel‐eluting balloon catheters (PEB) and drug‐eluting stents for treatment of bare‐metal stent restenosis (BMS‐ISR) have been demonstrated in several studies with follow‐up times of 9 to 12 months; however, the long‐term outcomes of ISR treatment are less defined.ObjectivesWe aimed to compare the long‐term efficacy of PEB and everolimus‐eluting stents (EES) for the treatment of BMS‐ISR.MethodsWe analyzed 3‐year clinical follow‐up data from patients included in the TIS randomized clinical study. A total of 136 patients with BMS‐ISR were allocated to receive treatment with either PEB or EES (68 patients with 74 ISR lesions per group).ResultsThe PEB and EES groups did not significantly differ in major adverse cardiac events‐free survival (MACE; P = .211; including individual events: CV death: P = .622; myocardial infarction: P = .650 or target vessel revascularization: P = .286) at 3‐year clinical follow‐up. No event‐free survival differences were found between the groups regarding overall mortality (P = .818), definite stent thrombosis (P = .165) or the second MACE (P = .270).ConclusionsAt the 3‐year follow‐up, no significant differences in clinical outcomes were found between iopromide‐coated PEB and EES for the treatment of BMS‐ISR. (ClinicalTrials.gov; https://clinicaltrials.gov; NCT01735825).
Tertiary Amine‐Naphthenic Acid Self‐Assembled Surfactants for Viscosity Reduction of Crude Oil
Authors: Liu Dongfang , Suo Yuxin , Tan Jiang , Zhu Peiyao , Zhao Jihe , Wang Baogang , Lu Hongsheng 
Published: July 2018

AbstractThe formation of low‐viscosity emulsions is a vital method for viscosity reduction of crude oil. Naphthenic acids, which are present in crude oil, are potential surface‐active substances. Tertiary amines with CO2 response can be self‐assembled in situ with the naphthenic acids in the crude oil to form a surfactant, which can emulsify the heavy crude oil and water to form an emulsion. The emulsion can be easily demulsified in the presence of CO2. N,N‐Dimethylbutylamine, N,N‐dimethyloctylamine, and N,N‐dimethyldodecylamine were used to prepare heavy crude oil emulsions in this work. This convenient emulsification and demulsification approach provides a new concept for pipeline transportation of heavy crude oil.
PKC epsilon signaling effect on actin assembly is diminished in cardiomyocytes when challenged to additional work in a stiff microenvironment
Authors: Mkrtschjan Michael A. , Solís Christopher , Wondmagegn Admasu Y. , Majithia Janki , Russell Brenda 
Published: July 2018

AbstractThe stiffness of the microenvironment surrounding a cell can result in cytoskeletal remodeling, leading to altered cell function and tissue macrostructure. In this study, we tuned the stiffness of the underlying substratum on which neonatal rat cardiomyocytes were grown in culture to mimic normal (10 kPa), pathological stiffness of fibrotic myocardium (100 kPa), and a nonphysiological extreme (glass). Cardiomyocytes were then challenged by beta adrenergic stimulation through isoproterenol treatment to investigate the response to acute work demand for cells grown on surfaces of varying stiffness. In particular, the PKCɛ signaling pathway and its role in actin assembly dynamics were examined. Significant changes in contractile metrics were seen on cardiomyocytes grown on different surfaces, but all cells responded to isoproterenol treatment, eventually reaching similar time to peak tension. In contrast, the assembly rate of actin was significantly higher on stiff surfaces, so that only cells grown on soft surfaces were able to respond to acute isoproterenol treatment. Förster Resonance Energy Transfer of immunofluorescence on the cytoskeletal fraction of cardiomyocytes confirmed that the molecular interaction of PKCɛ with the actin capping protein, CapZ, was very low on soft substrata but significantly increased with isoproterenol treatment, or on stiff substrata. Therefore, the stiffness of the culture surface chosen for in vitro experiments might mask the normal signaling and affect the ability to translate basic science more effectively into human therapy.
Correlation of flow complexity parameter with aneurysm rupture status
Authors: Hodis Simona 
Published: July 2018

AbstractRuptured aneurysms are known to have complex flow patterns and concentrated inflow jet, but a quantifiable measure for the degree of flow complexity in patient‐specific geometries has not been established. Previously, we proposed a flow complexity parameter that provides a quantitative description of the complexity of flow patterns through calculated curvature and torsion of the flow field. The purpose of the current study was to provide an analytic solution of the flow complexity parameter and assess a possible correlation with the rupture status of cerebral aneurysms by analyzing the parameter on five ruptured and five unruptured aneurysms from anterior communicating artery. We analyzed the flow complexity parameter in jet and non‐jet regions in order to measure the concentration of the jet flow and the complexity of the non‐jet flow. We found that on average, in a ruptured case the jet region is significantly less complex (4.5 times) than the jet region in an unruptured case, while the non‐jet region is significantly more complex (3.5 times) than the non‐jet region in an unruptured case. We also found a strong positive correlation of the non‐jet complexity with dome volume in ruptured cases, but no correlation of jet complexity with dome volume. These findings suggest that a ruptured aneurysm has more than 4 times more concentrated inflow jet and more than 3 times more complex flow patterns in non‐jet region than an unruptured aneurysm. This newly implemented kinematic parameter provides a measurable degree of complexity of flow patterns in cerebral aneurysms that can better assess aneurysm rupture risk.
Hurricane disturbance and forest dynamics in east Caribbean mangroves
Authors: Imbert Daniel 
Published: July 2018

AbstractDespite low plant diversity and structural simplicity, mangroves offer various ecosystem services to local human communities, including sheltering coastal social‐ecological systems from high‐energy storm damage. The expected increasing intensity of hurricanes due to climate change raises questions concerning the capacity of mangroves to resist and recover from such disturbances. Herein, this study contributes to a better understanding of (1) the relation between storm intensity and damage to mangrove vegetation, (2) the contributions of species‐specific as well as stand‐specific components of mangrove vegetation to ecosystem resistance, and (3) the recovery of pre‐hurricane forest structure through time. The first two issues have been addressed using a stand‐level approach implemented at two east Caribbean mangrove sites in response to three storm events. The third was addressed through a 23‐yr survey of forest recovery following the passage of a high‐energy storm across one of the two study sites. Generally, hurricane damage was primarily controlled by wind velocity, followed by the hydro‐geomorphic context of mangrove forests and species‐specific composition, respectively. The relationship between damage to trees and wind velocity evidenced a sigmoidal trend, with a maximum slope at a wind velocity averaging 130 and 180 km/h for higher vs. lower canopy stands, respectively. The red mangrove, Rhizophora mangle, was significantly less resistant to hurricane damage than was the black mangrove, Avicennia germinans. Unlike the fringe and scrub stands, inner, tall‐canopy stands fully recovered by the end of the study (23 yr). These stands were more resilient because of their growth performances. Finally, the time for east Caribbean mangroves to recover from high‐energy storms seems to fall within the range of the average return time of such disturbances. This may prevent such ecosystems from ever reaching a steady state.
Plant diversity and density predict belowground diversity and function in an early successional alpine ecosystem
Authors: Porazinska Dorota L. , Farrer Emily C. , Spasojevic Marko J. , Bueno de Mesquita Clifton P. , Sartwell Sam A. , Smith Jane G. , White Caitlin T. , King Andrew J. , Suding Katharine N. , Schmidt Steve K. 
Published: July 2018

AbstractDespite decades of interest, few studies have provided evidence supporting theoretical expectations for coupled relationships between aboveground and belowground diversity and ecosystem functioning in non‐manipulated natural ecosystems. We characterized plant species richness and density, soil bacterial, fungal and eukaryotic species richness and phylogenetic diversity (using 16S, ITS, and 18S gene sequencing), and ecosystem function (levels of soil C and N, and rates of microbial enzyme activities) along a natural gradient in plant richness and density in high‐elevation, C‐deficient soils to examine the coupling between above‐ and belowground systems. Overall, we observed a strong positive relationship between aboveground (plant richness and density) and belowground (bacteria, fungi, and non‐fungal eukaryotes) richness. In addition to the correlations between plants and soil communities, C and N pools, and rates of enzyme activities increased as plant and soil communities became richer and more diverse. Our results suggest that the theoretically expected positive correlation between above‐ and belowground communities does exist in natural systems, but may be undetectable in late successional ecosystems due to the buildup of legacy organic matter that results in extremely complex belowground communities. In contrast, microbial communities in early successional systems, such as the system described here, are more directly dependent on contemporary inputs from plants and therefore are strongly correlated with plant diversity and density.
Magnitude of acute toxicity of marine sediments amended with conventional copper and nanocopper
Authors: Parks Ashley N. , Cashman Michaela A. , Perron Monique M. , Portis Lisa , Cantwell Mark G. , Katz David R. , Ho Kay T. , Burgess Robert M. 
Published: July 2018

Abstract

It is well known that copper (Cu) is toxic to marine organisms. We measured and compared the acute toxicity of several forms of Cu (including nanoCu) amended into a marine sediment with mysids and amphipods. For all the forms of Cu tested, toxicity, measured as the median lethal concentration, ranged from 708 to &gt; 2400 mg Cu/kg (dry sediment) for mysids and 258 to 1070 mg Cu/kg (dry sediment) for amphipods. Environ Toxicol Chem 2018;37:2677–2681. © 2018 SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.
Percentage of methylmercury in the muscle tissue of freshwater fish varies with body size and age and among species
Authors: Lescord Gretchen L. , Johnston Thomas A. , Branfireun Brian A. , Gunn John M. 
Published: July 2018

Abstract

It is commonly assumed that most (&gt;95%) of the mercury (Hg) found in fish muscle is the toxic form, methylmercury (MeHg), due to its efficient assimilation and retention in biotic tissue. However, this assumption is largely based on studies examining the percentage of MeHg (%MeHg [the fraction of total Hg as MeHg]) in muscle from mostly large-bodied predatory fish; less is known about the %MeHg in smaller bodied individuals or those of different trophic guilds. The present study analyzed MeHg and total Hg concentrations in the muscle of 2 large-bodied piscivores (walleye and northern pike), one large-bodied benthivore (white sucker), and 2 small-bodied forage fish (sculpins and shiners) across a broad size range. We found substantially lower %MeHg than the commonly assumed 95% in several fish (e.g., 17 individuals had &lt;70% MeHg). Muscle %MeHg significantly increased with size and age in all species except walleye, which had significantly higher %MeHg than pike or suckers, particularly in smaller and younger fish (e.g., 18–21% higher at 10 g; 5–11% higher at 500 g). Results of predictive modeling suggest that muscle %MeHg is higher in pelagic-feeding fish and those with lower lipid content, although model results varied significantly among species. According to our findings, total Hg measurement in muscle is not an appropriate proxy for MeHg in smaller fish from all species, an important consideration for future piscine Hg studies and monitoring. Environ Toxicol Chem 2018;37:2682–2691. © 2018 SETAC
Abstract
The percentage of mercury as methylmercury (%MeHg) in fish muscle increases with body size in northern pike (P) and white sucker (S) but not walleye (W).
Assessing the impact of human activities on surface pollen assemblages in Qinghai Lake Basin, China
Authors: Wei Haicheng , Yuan Qin , Xu Qinghai , Qin Zhanjie , Wang Lingqing , Fan Qishun , Shan Fashou 
Published: July 2018

ABSTRACTThe aim of this study is to evaluate the local impact of human activities on surface pollen assemblages and identify pollen indicators associated with grazing and cultivation in the Qinghai‐Tibetan Plateau. We analyzed 80 surface and 10 dung pollen samples from five communities of vegetation in the Qinghai Lake Basin. Each vegetation zone was identifiable based on surface pollen assemblages. Principal component analysis of 33 pollen taxa and two supplementary variables of human influences was used to assess the impact of anthropogenic activities on surface pollen assemblages in the Qinghai Lake Basin. Surface pollen assemblages were moderately influenced by cultivation, as indicated by the content of the cultivation‐associated Hordeum‐type and Brassiaceae pollen. Severe grazing led to changes in pollen assemblages, including increases in Chenopodiaceae, Plantago, Potentilla‐type, Thymelaeaceae and Aster‐type pollen. Pollen assemblages are similar among dung samples and are dominated by Artemisia, Poaceae, Fabaceae and Asteraceae. Hordeum‐type pollen content is relatively higher in dung samples, indicating herbivores are important in the dispersion of Cerealia Poaceae pollen into pastures. Characterizing modern pollen assemblages will provide a more precise reference for reconstructing prehistoric human activities during the Holocene based on fossil pollen assemblages in the Qinghai Lake Basin.
Crowdsourcing Trauma: Psychopathology in a Trauma‐Exposed Sample Recruited via Mechanical Turk
Authors: van Stolk‐Cooke Katherine , Brown Andrew , Maheux Anne , Parent Justin , Forehand Rex , Price Matthew 
Published: July 2018

AbstractAlthough crowdsourcing websites like Amazon's Mechanical Turk (MTurk) allow researchers to conduct research efficiently, it is unclear if MTurk and traditionally recruited samples are comparable when assessing the sequela of traumatic events. We compared the responses to validated self‐report measures of posttraumatic stress disorder (PTSD) and related constructs that were given by 822 participants recruited via MTurk and had experienced a DSM‐5 Criterion A traumatic event to responses obtained in recent samples of participants recruited via traditional methods. Results suggested that the rate of PTSD in the present sample (19.8%) was statistically higher than that found in a recent systematic review of studies that used only traditional recruitment methods. The severity of PTSD reported in the MTurk sample was significantly greater than that reported in a college sample, d = 0.24, and significantly less than that reported in a veteran sample, d = 0.90. The factor structure of PTSD found in the MTurk sample was consistent with prevailing models of PTSD. Findings indicate that crowdsourcing may improve access to this hard‐to‐reach population.
Mineral iron utilization by natural and cultured Trichodesmium and associated bacteria
Authors: Basu Subhajit , Shaked Yeala 
Published: July 2018

AbstractThe high iron (Fe) demands of Trichodesmium, a keystone nitrogen‐fixing cyanobacterium, are often met by dust deposition at the ocean surface. Following up on our findings of unique dust capturing and processing by Trichodesmium, we explored the ability of natural Trichodesmium colonies from the Gulf of Aqaba and Fe‐limited laboratory culture (IMS101) to obtain Fe from the mineral ferrihydrite and compete with their epibiotic bacteria for this Fe source. To study this complex system, we carefully optimized a radiotracer method ensuring complete removal of external ferrihydrite and efficient separation of bacteria from the colonies. Trichodesmium‐only uptake rates of natural colonies were 5–50 times faster than those of laboratory culture, suggesting that natural colonies acquire ferrihydrite at a greater efficiency. In some days, total uptake rates of natural colonies exceeded dissolved Fe release from ferrihydrite, indicating that the colonies enhance the mineral dissolution rate. Furthermore, uptake rates of bacteria associated with natural colonies were faster than those of bacteria associated with the culture, implying that the bacteria benefit from the Trichodesmium‐enhanced mineral dissolution. At the cellular level, surface area normalized uptake rates of bacteria always exceeded those of cultured Trichodesmium, but in natural populations, the dominance shifted between Trichodesmium and bacteria on different days. At the community level, when accounting for the total bacteria and Trichodesmium cells, Trichodesmium dominated Fe uptake in both cultured and natural colonies. Overall, our findings suggest that natural Trichodesmium colonies are exceptionally adapted for accessing mineral Fe and maintaining a sustainable relationship with their associated bacteria.