bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blood pressure response to angiotensin II is enhanced in obese Zucker rats and is attributed to an aldosterone‐dependent mechanism
Authors: Müller‐Fielitz Helge , Lau Margot , Jöhren Olaf , Stellmacher Florian , Schwaninger Markus , Raasch Walter 
Published: March 2012

BACKGROUND AND PURPOSE Plasma aldosterone levels correlate positively with obesity, suggesting a link between the hypertension associated with obesity and increased mineralocorticoid levels. We tested the hypothesis that aldosterone is involved in the BP response to angiotensin II (AngII) in obese rats.EXPERIMENTAL APPROACH Lean (LZR) and obese (OZR) Zucker rats were treated with AngII (9 µg·h−1; 4 weeks), and BP and plasma AngII and aldosterone were determined.KEY RESULTS Chronic AngII increased the BP in OZR markedly more so than in LZR. Plasma AngII levels in LZR and OZR were similar after AngII treatment. The AngII stimulated a rise in plasma aldosterone that was sixfold more in OZR than in LZR. The thickness of the zona glomerulosa of the adrenal glands was selectively increased by AngII in OZR. Adrenal mRNA levels of CYP11B2 aldosterone synthase and the AT1B receptor were selectively increased in AngII‐treated OZR. The BP response to chronic AngII stimulation was diminished in OZR after adrenalectomy when plasma aldosterone was absent. Acute bolus injections of AngII did not increase the BP response or aldosterone release in OZR.CONCLUSIONS AND IMPLICATIONS The AngII‐induced BP response is enhanced in obesity and this is associated with a specific increase in circulating aldosterone. Due to the AngII‐induced growth of the zona glomerulosa in OZR, the AT1B receptors and aldosterone synthase may be selectively enhanced in obesity under concomitant AngII stimulation, increasing the adrenal synthesis of aldosterone. Our results confirm functionally that aldosterone plays a major role in obesity‐related hypertension.
Myocardial β2‐adrenoceptor gene delivery promotes coordinated cardiac adaptive remodelling and angiogenesis in heart failure
Authors: Rengo G , Zincarelli C , Femminella GD , Liccardo D , Pagano G , de Lucia C , Altobelli GG , Cimini V , Ruggiero D , Perrone‐Filardi P , Gao E , Ferrara N , Lymperopoulos A , Koch WJ , Leosco D 
Published: March 2012

BACKGROUND AND PURPOSE We investigated whether β2‐adrenoceptor overexpression could promote angiogenesis and improve blood perfusion and left ventricular (LV) remodeling of the failing heart.EXPERIMENTAL APPROACH We explored the angiogenic effects of β2‐adrenoceptor overexpression in a rat model of post‐myocardial infarction (MI) heart failure (HF). Cardiac adenoviral‐mediated β2‐adrenoceptor overexpression was obtained via direct intramyocardial injection 4‐weeks post‐MI. Adenovirus(Ad)‐GFP and saline injected rats served as controls. Furthermore, we extended our observation to β2‐adrenoceptor −/− mice undergoing MI.KEY RESULTS Transgenes were robustly expressed in the LV at 2 weeks post‐gene therapy, whereas their expression was minimal at 4‐weeks post‐gene delivery. In HF rats, cardiac β2‐adrenoceptor overexpression resulted in enhanced basal and isoprenaline‐stimulated cardiac contractility at 2‐weeks post‐gene delivery. At 4 weeks post‐gene transfer, Ad‐β2‐adrenoceptor HF rats showed improved LV remodeling and cardiac function. Importantly, β2‐adrenoceptor overexpression was associated with a markedly increased capillary and arteriolar length density and enhanced in vivo myocardial blood flow and coronary reserve. At the molecular level, cardiac β2‐adrenoceptor gene transfer induced the activation of the VEGF/PKB/eNOS pro‐angiogenic pathway. In β2‐adrenoceptor−/− mice, we found a ∼25% reduction in cardiac capillary density compared with β2‐adrenoceptor+/+ mice. The lack of β2‐adrenoceptors was associated with a higher mortality rate at 30 days and LV dilatation, and a worse global cardiac contractility compared with controls.CONCLUSIONS AND IMPLICATION β2‐Adrenoceptors play an important role in the regulation of the angiogenic response in HF. The activation of VEGF/PKB/eNOS pathway seems to be strongly involved in this mechanism.
Acreage Response to Whole Farm Income Stabilisation Programmes
Authors: Bakhshi Samira , Gray Richard S. 
Published: March 2012

AbstractThis article investigates whether Canadian whole farm programmes, which fall under the WTO category of Green Box subsidies, are truly production neutral. Theory suggests that with non‐constant risk aversion, risky decisions can be influenced by both the level of expected wealth (i.e. the wealth effect) and the variability of wealth (i.e. the insurance effect). Unlike previous approaches, this article is able to extend a framework developed by Chavas and Holt to formally incorporate the insurance effect into the acreage allocation decisions. By applying the theoretical model to acreage data in the Canadian Prairies, the results reveal that the whole farm income stabilisation programmes had large impacts on acreage choices through wealth and insurance effects. From a WTO perspective, the results underline the inherent difficulty in designing programmes that will reduce the risk faced by farmers without altering behaviour.
Association of Maturation Period Blood Pressure with Dialysis Access Patency
Authors: Wayne Erik J. , Brier Michael E. , Dwyer Amy C. 
Published: March 2012

AbstractProblematic dialysis vascular access is a major health issue. The purpose of this study was to evaluate for potentially modifiable factors associated with access patency, particularly, the association of early postoperative, or maturation period, blood pressure with patency. A retrospective review was performed of patients who had undergone placement of an arteriovenous fistula or graft. Demographic, operative, and postoperative factors were evaluated for possible association with access primary patency using univariate and multivariate Cox regression analyses. Seventy‐three patients over a 3‐year review period were examined. Overall analysis showed a significant association of absence of peripheral vascular disease, aspirin use, and absence of previous permanent dialysis access with higher primary patency rates. Fistula subgroup analysis showed that higher blood pressure during the maturation period relative to preoperative blood pressure was associated with lower patency rates. For grafts, race was significantly associated with patency, with blacks having higher patency rates than whites. Multiple clinical factors were found to have a significant association with dialysis access primary patency. The finding of an association of maturation period blood pressure with fistula patency suggests that the maturation period environment, specifically hemodynamics during this time, may play an important role in dialysis access patency.
Symptomatic Intradialytic Hypotension and Mortality: An Opinionated Review
Authors: Henderson Lee W. 
Published: March 2012

AbstractThe unchanging rate of symptomatic hypotension that attends maintenance hemodialysis and its link to sodium/volume overload are explored. Correlations between interdialytic weight gain, ultrafiltration rate, hypertension, and mortality are found to be strong. Suggestions/opinions for correcting this unfortunate clinical reality are offered.
Assessment of Environmental Impacts of an Aging and Stagnating Water Supply Pipeline Network
Authors: Venkatesh G. , Brattebø Helge 
Published: March 2012

SummaryAging urban infrastructure is a common phenomenon in industrialized countries. The urban water supply pipeline network in the city of Oslo is an example. Even as it faces increasing operational, maintenance, and management challenges, it needs to better its environmental performance by reducing, for instance, the associated greenhouse gas emissions. In this article the authors examine the environmental life cycle performance of Oslo's water supply pipelines by analyzing annual resource consumption and emissions as well as life cycle assessment (LCA) impact potentials over a period of 16 years, taking into account the production/manufacture, installation, operation, maintenance, rehabilitation, and retirement of pipelines. It is seen that the water supply pipeline network of Oslo has already reached a state of saturation on a per capita basis, that is, it is not expanding any more relative to the population it serves, and the stock is now rapidly aging. This article is part of a total urban water cycle system analysis for Oslo, and analyzes more specifically the environmental impacts from the material flows in the water distribution network, examining six environmental impact categories using the SimaPro (version 7.1.8) software, Ecoinvent database, and the CML 2001 (version 2.04) methodology. The long‐term management of stocks calls for a strong focus on cost optimization, energy efficiency, and environmental friendliness. Global warming and abiotic depletion emerge as the major impact categories from the water pipeline system, and the largest contribution is from the production and installation phases and the medium‐size pipelines in the network.
Meta‐Analysis of Life Cycle Assessment Studies on Electricity Generation with Carbon Capture and Storage
Authors: Schreiber Andrea , Zapp Petra , Marx Josefine 
Published: March 2012

SummaryIn the last decade, numerous life cycle assessments (LCAs) on environmental impacts of electricity generation with carbon capture and storage (CCS) have been conducted. This meta‐analysis comprises 15 LCAs of the three CCS technologies (postcombustion, oxyfuel, precombustion) with a focus on greenhouse gas reduction for different regions (Europe, United States, Japan, global), different fuels (hard coal, lignite, natural gas), and different time horizons (between the present and 2050). It presents a condensed overview of methodological variations, findings, and conclusions gathered from these LCAs.All LCAs show the expected reduction in global warming potential but an increase in many other impact categories, regardless of capture technology, time horizon, or fuel considered. Three parameter sets have been identified that have a significant impact on the results: (1) power plant efficiency and energy penalty of the capture process, (2) carbon dioxide capture efficiency and purity, and (3) fuel origin and composition.This meta‐analysis proves that LCA is a helpful tool to investigate the variety of environmental consequences associated with CCS. However, there are differences in the underlying assumptions of the LCAs as well as methodological shortcomings that yield heterogeneity of results. Without a better understanding of the technology, it is not possible to give a comprehensive picture. There also remains a wide field of subjects and technologies that have not yet been covered.
A Simplified Life Cycle Approach for Assessing Greenhouse Gas Emissions of Wind Electricity
Authors: Padey Pierryves , Blanc Isabelle , Le Boulch Denis , Xiusheng Zhao 
Published: March 2012

SummaryA full life cycle assessment (LCA) is usually a time, energy, and data‐intensive process requiring sophisticated methodology. Our meta‐analysis of life cycle greenhouse gas (GHG) emissions of wind electricity highlights several key, sensitive parameters to provide a better understanding of the variability in LCA results, and then proposes a methodology to establish a simplified, streamlined approach based on regressions built on these key parameters. Wind electricity's environmental performance can be linked to three essential components: technological (e.g., manufacturing), geographical (e.g., wind speed), and LCA methodology (e.g., product lifetime).A regression has been derived based on detailed LCA results from a representative sample of 17 industrial wind turbines manufactured and recently installed in Europe on average land configurations. Simple GHG performance (i.e., emissions) curves depending on average on‐site wind speed and wind turbine lifetime are proposed. Whatever the system power, considering the full range of possible wind speeds in Europe (4 to 9 meters per second [m/s]) and a lifetime of 10 to 30 years, emissions vary from 8.7 to 76.7 grams of carbon dioxide equivalent per kilowatt‐hour (g CO2‐eq/kWh) when the wind speed is less than 6.5 m/s, and from 4.5 to 22.2 g CO2‐eq/kWh when the wind speed is 6.5 m/s or greater. This second situation with a turbine lifetime of 20 years is assumed to be most realistic based on economic criteria.This research presents simplified models as an alternative to detailed LCA. The methodology has been applied as a first trial to wind electricity and could be applied to other energy pathways.
Opioid‐Free Perioperative Analgesia for Hemicolectomy in a Patient With Opioid‐Induced Delirium: A Case Report and Review of the Analgesic Efficacy of the Alpha‐2 Agonist Agents
Authors: Patil Sheetal K. , Anitescu Magdalena 
Published: March 2012

Abstract:  Surgical pain in patients with documented opioid‐induced delirium can be difficult to treat. We present a case of a patient undergoing laparoscopic hemicolectomy effectively treated with an opioid‐free, alpha‐2 adrenoreceptor agonist analgesic regimen.Case report: A 21‐year‐old woman with persistent abdominal pain presented to the operating room for laparoscopic hemicolectomy for redundant right colon. Her medical history included a recently diagnosed postoperative opioid‐induced delirium. Epidural infusion with local anesthetic offered partial pain relief with sensory levels of T9‐L2. With the addition of dexmedetomidine infusion in the immediate postoperative period, the patient was comfortable with pain scores of 1 to 2/10 on Numerical Rating Scale (NRS). On postoperative day 1, the infusion was discontinued and the clonidine, 12 μg/hours was added to the epidural bupivacaine. With increased sedation 48 hours later, neuraxial clonidine was discontinued in favor to transdermal clonidine 0.1 mg/week, which was maintained until hospital discharge. Pain scores were maintained at 2 to 3/10 on NRS for the next 3 days when increased abdominal distention because of abscess formation rendered a new surgical intervention. The analgesia for the exploratory laparoscopy was maintained using epidural clonidine and bupivacaine infusion as well as intravenous dexmedetomidine, which were maintained another 2 days. Pain scores remained minimal until discharged home 3 day later. Discussion: Nonopioid analgesic regimens are beneficial in patients at risk of postoperative cognitive dysfunction attributable to opioids. Successful postoperative analgesia was achieved in our patient by alternating various routes of administration of alpha‐2 adrenoreceptor agonists.
Impact of transfusion of autologous 7‐ versus 42‐day‐old AS‐3 red blood cells on tissue oxygenation and the microcirculation in healthy volunteers
Authors: Roberson Russell S. , Lockhart Evelyn , Shapiro Nathan I. , Bandarenko Nicholas , McMahon Timothy J. , Massey Michael J. , White William D. , Bennett‐Guerrero Elliott 
Published: March 2012

BACKGROUND: Stored red blood cells (RBCs) accumulate biochemical and biophysical changes. Maximum storage duration is based on acceptable in vitro characteristics and 24‐hour survival, but not RBC function. Relatively little is known about the impact of RBC storage duration on oxygenation and the microcirculation.STUDY DESIGN AND METHODS: Eight healthy subjects donated a double RBC apheresis, which were prestorage leukoreduced and processed in AS‐3. Subjects were transfused 1 unit of RBCs at 7 and 42 days after blood collection. Measurements of percentage of tissue oxygenation in the thenar eminence muscle (StO2) and brain (SctO2) were recorded with Food and Drug Administration–cleared noninvasive devices. Sublingual microvascular blood flow (microcirculatory flow index [MFI]) was quantified before and after RBC transfusion using a video microscope. Raw electronic data for all measurements were analyzed by a blinded observer at a core laboratory.RESULTS: The only pre‐ versus posttransfusion change observed in measurements of SctO2, StO2, or MFI was a very small increase in SctO2, from 70.4 to 71.8 (means, p = 0.032) at 7 days. There was no significant difference in the amount of pre–post change at 7 days versus 42 days for any of the measures.CONCLUSION: Transfusion of 1 unit of 42‐day‐stored RBCs to healthy subjects has no overt detrimental effect on tissue oxygenation or the microcirculation assessed by clinically available monitors.
A rest period does not affect in vitro storage properties in apheresis platelets collected from the buffy coat layer
Authors: Wagner Stephen J. , Seetharaman Shalini , Kurtz James 
Published: March 2012

BACKGROUND: A previous study demonstrated that several in vitro storage properties of apheresis platelets (PLTs) that are isolated by sedimentation against the collection container and subsequently resuspended can benefit from a rest period before continuous agitation. This study examines whether the in vitro storage properties of apheresis PLTs isolated by collection from the buffy coat layer benefit from a rest period before agitation.STUDY DESIGN AND METHODS: Freshly collected apheresis PLTs (Trima, GambroBCT) were divided into five 60‐mL aliquots. One aliquot was immediately placed on a flat‐bed agitator; the other aliquots were held on a laboratory bench for 1, 2, 4, and 6 hours before continuous agitation. Samples were obtained on Days 1, 5, and 7 for standard in vitro PLT assays. The experiment was repeated 12 times.RESULTS: For each sampling day, no significant differences were observed in aliquots held with or without a rest period for any of the following PLT properties: PLT content, mean PLT volume, pH, pCO2, bicarbonate, glucose, lactate, hypotonic shock response, extent of shape change, aggregation, morphology, CD62P, CD63, and CD42b. Although regression analysis identified several in vitro properties whose mean levels appeared to improve with increasing length of the rest period, maximum differences in mean levels were small (<6%).CONCLUSION: The in vitro storage properties of Trima apheresis PLTs isolated from the buffy coat layer do not benefit from a rest period.
Pharmacologic and Nonpharmacologic Therapies for Stroke Prevention in Nonvalvular Atrial Fibrillation
Authors: HAN JIANGLI , CHENG JIE , MATHURIA NILESH 
Published: March 2012

Thromboembolism is the crucial cause of ischemic stroke in patients with atrial fibrillation (AF). Anticoagulation therapy with vitamin K antagonists, such as warfarin, have been proven to be effective for stroke prevention in AF. Nonetheless, the use of warfarin may be limited due to increased risk of bleeding, the potential interaction with multiple foods and drugs, and the need for routine coagulation monitoring. Over the last decade anticoagulants, such as dabigatran and rivaroxaban, have been developed and have shown superiority compared to warfarin for preventing stroke in patients with nonvalvular AF in large randomized trials. In addition, on account of the risk of thrombus formation in the left atrial appendage (LAA), many nonpharmacologic approaches have been developed to reduce stroke risk in patients with AF who are not candidates for anticoagulant therapy. Surgical, epicardial, and endovascular techniques for LAA closure are being investigated currently. Both novel pharmacotherapy and nonpharmacologic approaches for stroke prevention will be detailed in this review.(PACE 2012;XX:1–11)
Effect of Bioimpedance Body Composition Analysis on Function of Implanted Cardiac Devices
Authors: BUCH ERIC , BRADFIELD JASON , LARSON TIANNE , HORWICH TAMARA 
Published: March 2012

Background:

It is routinely recommended that patients with pacemakers, implantable cardioverter defibrillators (ICD), and cardiac resynchronization therapy‐defibrillators (CRT‐D) avoid bioelectrical impedance analysis (BIA)—a commonly used method to estimate body composition—because of the concern for the potential for BIA interference with pacemaker or ICD function. However, the prevalence of such interference is not known.
Objective:

Assess for incidence of interference between BIA and ICD or CRT‐D devices.
Methods and Results:

Twenty patients with heart failure and cardiac implanted electronic devices (50% ICD, 50% CRT‐D) underwent BIA during real‐time device interrogation to detect interference. Study patients were 90% male, with mean age 54 ±14 years, and mean LVEF 23 ± 11%. Devices from all four leading cardiac device manufacturers were included. Device therapies were temporarily disabled to prevent inappropriate shocks. During body composition testing using BIA, no evidence of interference with ICD function was seen in any patient, including no telemetry disruption, no oversensing on any lead, and no patient symptoms.
Conclusions:

Despite the manufacturers’ recommendation to avoid BIA in patients with ICDs, this study showed no evidence of any interference in 20 patients. Bioimpedance analysis might be safe in such patients, but further confirmatory studies are required. (PACE 2012; 35:681–684)
Impact of a Recent Lead Recall on Utilization of Implantable Cardioverter Defibrillators: Data from the NCDR ICD Registry™
Authors: BHATT PARAS , CURTIS JEPTHA , WANG YONGFEI , LAMPERT RACHEL 
Published: March 2012

Impact of Recalls on ICD Utilization. Introduction: Underutilization of ICDs is well documented. It has been hypothesized that device recalls, and the resultant negative publicity, may contribute.
Methods and Results: To determine if the October 2007 recall of the Medtronic Fidelis lead was associated with a decrease in volume of ICD procedures in the United States, we analyzed data submitted to the ICD Registry™ between July 2006 and December 2008. Time‐series analyses were performed comparing actual and predicted implant volumes following the recall, using monthly data from July 2006 to September 2007 to establish a trend line. Observed data points falling outside the 95% CIs from the trend line were considered statistically significant. The study cohort includes 173,616 implantations in 658 hospitals. Before October 2007, an average of 5,952 devices, 4,910 for primary prevention, were implanted per month. Following the recall, the average monthly number of implants was modestly lower at 5,623 (P = 0.05), 4,601 for primary prevention (P = 0.01.) However, as volume was decreasing prior, in time‐series analysis, the observed monthly implant volume for primary prevention devices differed from expected based on the trend line for only 1 month. The proportion of Medtronic implants declined from 51.1% in the 15 months prior to the recall to 45.8% in the 15 months of the recall or after (P < 0.01), falling outside the 95% CI of the trend line for 3 months in time‐series analysis.
Conclusions:
A recent well‐publicized lead recall had minimal impact on ICD utilization either overall or for primary prevention. (J Cardiovasc Electrophysiol, Vol. 23, pp. 861‐865, August 2012)