bluuebunny/crossref_metadata_2025_split huggingface dataset:
A low‐carbohydrate diet in overweight patients undergoing stable statin therapy raises high‐density lipoprotein and lowers triglycerides substantially
Authors: Gann Dietmar 
Published: June 2007

AbstractBackground: A low‐carbohydrate diet remains controversial, especially in patients with arteriosclerotic heart disease.Hypothesis: This study was undertaken to evaluate the effect of a low‐carbohydrate diet on the lipid levels in obese patients with known arteriosclerotic heart disease on chronic statin therapy.Methods: Thirty‐eight overweight patients with angiographically documented arteriosclerotic heart disease were followed in a private cardiology practice setting. All patients were undergoing stable statin therapy. Patients received a 15‐min consultation and a 4‐page pamphlet explaining a low‐carbohydrate diet; no other diet instruction was given. Patients were followed weekly for 2 weeks, then monthly for 3 months, then every third month. A fasting finger stick lipid panel (cholesterol, high‐density and low‐density lipoprotein [HDL/ LDL], triglycerides, and glucose) was obtained with each visit and patients were weighed in street clothes.Results: The 38 patients were followed for a average of 11.8 months (range 6‐22 months). Average body mass index declined from 33.5 kg/m2 before to 27.9 kg/m2 at the end of the study. Weight loss averaged 31 lbs (range 16‐107 lbs). Tri‐glyceride levels were lowered by 29.5%, HDL raised by 17.6%, and cholesterol decreased by 8.4%. The cholesterol/ HDL ratio changed from 5.31 to 3.78 and LDL cholesterol decreased by 5%.Conclusion: The addition of a low‐carbohydrate diet for overweight patients with known coronary artery disease undergoing stable statin therapy causes significant weight loss and a favorable change in the lipid panel.
Aortic valve replacement in patients 70 years and older
Authors: Salazar Eduardo , Torres Jorge , Barragán Rodolfo , López Mauricio , Lasses Luis Alberto 
Published: June 2007

AbstractBackground: Aortic valvular disease is the most common valvular lesion among elderly patients. Because of changing demographics, it has become increasingly frequent. Aortic valve replacement (AVR) is the only effective treatment for aortic valvular disease.Hypothesis: This study was undertaken to evaluate the results of AV R in an elderly population.Methods: Data were retrospectively analyzed in 117 consecutive patients (mean age 73.8 years) who underwent AV R between 1991 and 2002.Results: Pure or predominant severe aortic stenosis was present in 108 patients. Nine patients had severe aortic regurgitation. Before valve replacement, 62.4% of the patients were in New York Heart Association (NYHA) functional class III‐IV. A bioprosthesis was implanted in 62.4% of the patients, and 37.6% received a mechanical valve. Concomitant cardiac surgical procedures were performed in 25 patients (coronary artery bypass graft in 22, mitral valve replacement in 3). There were 17 deaths, giving a perioperative mortality rate of 14.5%. Multivariate logistic regression showed that repeat surgery for bleeding, prolonged cardiopulmonary bypass time, postoperative respiratory failure, and postoperative acute renal insufficiency were significant independent predictors of operative mortality. Of the 100 hospital survivors, 78 were followed for a mean of 42.9 months. There were six deaths during follow‐up; only two of these were cardiac related. Five‐year actuarial survival for all patients and for hospital survivors were 70 and 91.1%, respectively. One year post surgery, all patients were in NYHA functional class I‐II.Conclusion: In a selected patient population, AV R in the elderly is associated with acceptable mortality and morbidity. The outlook for hospital operative survivors is excellent with improved quality of life and an expected survival normal for this particular age.
Role of N‐acetylcysteine in prevention of contrast‐induced nephropathy after cardiovascular procedures: A meta‐analysis
Authors: Misra Deepika , Leibowitz Keith , Gowda Ramesh M. , Shapiro Michael , Khan Ijaz A. 
Published: June 2007

AbstractBackground: Contrast‐induced nephropathy is one of the common causes of acute renal insufficiency after cardiovascular procedures.Hypothesis: The objective of this paper was to analyze the published data on the usefulness of N‐acetylcysteine in the prevention of contrast‐induced nephropathy after these procedures.Methods: Trials were selected if they were prospective, randomized, controlled, had selected patients with impaired renal function, used low‐osmolality, nonionic contrast media intra‐arterially, administered a total of four doses of N‐acetyl‐cysteine in addition to intravenous saline hydration, and had contrast‐induced nephropathy as their primary outcome. Contrast‐induced nephropathy was defined as an increase in serum creatinine concentration by > 0.5 mg/dl or a 25% increase above baseline at or within 48 h post procedure. Meta‐analysis was performed using the Fisher's Combined Test with a measure of effect size. The magnitude of the N‐acetyl‐cysteine effect was estimated using random‐effects models. Homogeneity was evaluated using the chi‐square test of homogeneity and standard Q statistic. Reporting bias was explored by the Rosenthal method.Results: The Fisher's Combined Test was significant at p < 0.005 in favor of N‐acetylcysteine. The size of the N‐acetylcysteine effect was to reduce contrast‐induced nephropathy by 20%. There was a 62% relative risk reduction in contrast‐induced nephropathy with N‐acetylcysteine using a fixed‐effects model, and a 70% relative risk reduction using the random‐effects model. In addition, we found that 27 unpublished trials showing no effects of N‐acetylcysteine would exist to overturn the combined significance of p < 0.005 of the five trials in our meta‐analysis.Conclusion: Oral administration of N‐acetylcysteine in addition to intravenous saline hydration has a beneficial effect in the prevention of contrast‐induced nephropathy after cardiovascular procedures in patients with impaired renal function.
Long‐term outcome after senning operation for transposition of the great arteries
Authors: Agnetti A. , Carano N. , Cavalli C. , Tchana B. , Bini M. , Squarcia U. , Frigiola A. 
Published: June 2007

AbstractBackground: The Senning operation for transposition of the great arteries (TGA) was first introduced by Senning in 1959 and was revived by Quaegebeur et al. in the late 1970s, thus becoming the intervention of choice for the correction of TGA in many centers.Hypothesis: The purpose of this study was to evaluate the long‐term follow‐up of a group of patients undergoing surgery with the Senning procedure for TGA.Methods: From November 1978 to November 1987, 73 consecutive patients underwent the Senning operation. The 70 survivors had an average follow‐up of 19 years (16‐25 years).Results: (1) Cardiac rhythm: with time there was a progressive decrease in stable sinus rhythm (60% after 20 years) and a progressive increase of supraventricular tachyarrhythmias requiring therapy (10% after 20 years). (2) Right ventricular function: 20% of the patients had reduced ejection fraction. (3) Late mortality: in the last 12 years of follow‐up years there were two sudden deaths (2.8%). (4) Functional status: 80% of patients were in NYHA class I, 17% in class II, and 3% in class III.Conclusions: Our results confirm that the patients who undergo the Senning procedure have a progressive loss of sinus rhythm, an increase in active arrhythmias, and other important adverse outcomes such as late sudden death and a decrease in right ventricular function; however, most patients (93% in our series) are alive and in good functional status.
Impact of left ventricular diastolic function on exercise capacity in patients with chronic mitral regurgitation: An exercise echocardiography study
Authors: Kim Hyung‐Kwan , Kim Yong‐Jin , Chung Joong‐Wha , Sohn Dae‐Won , Park Young‐Bae , Choi Yun‐Shik 
Published: June 2007

AbstractBackground: Mitral regurgitation (MR) is known as one of the most frequent causes of heart failure and sudden death. In spite of increasing prevalence of MR, there have been no available data on cardiac determinants of exercise capacity in patients with chronic MR.Hypothesis: This study aimed to investigate cardiac determinants of exercise capacity in patients with chronic MR.Methods: We consecutively enrolled 32 patients (11 men, mean age: 44 ± 14 years) who had greater than moderate MR with normal left ventricular (LV) systolic function (LV ejection fraction > 50%). Conventional echocardiographic indices and parameters measured by Doppler tissue imaging at septal side of mitral annulus were obtained before exercise. Mitral regurgitation fraction, forward stroke volume, pulmonary venous flow velocities, and systolic pulmonary artery pressure (sPAP) were also obtained with standard methods.Results: Left ventricular ejection fraction was 61 ± 6% and MR fraction was 48 ± 13%. All patients finished a symptom‐limited treadmill exercise test with a peak heart rate of > 85% of predicted maximum heart rate. Mean exercise time was 9.95 ± 2.17 min, corresponding to 11 ± 2 metabolic equivalents. Among pre‐exercise echocardiographic variables, only early diastolic mitral annulus velocity (E') and pulmonary venous reversal flow velocity (PVa) showed a significant correlation with exercise time (r = 0.44, p = 0.011, and r = −0.40, p = 0.040, respectively), which persisted after multivariate analysis (p = 0.011 and 0.038, respectively). Other parameters such as systolic mitral annulus velocity, resting and post‐exercise sPAP, forward stroke volume, LV size, LV ejection fraction, left atrial size, and regurgitant fraction showed no significant correlation.Conclusions: Left ventricular diastolic function is an important determinant of exercise capacity in patients with chronic MR. Both E' and PVa, accepted surrogate estimates for LV diastolic function, may be useful for identifying patients with chronic MR and with poor exercise capacity.
Relationship of carotid intima‐media thickness, pulse wave velocity, and ankle brachial index to the severity of coronary artery atherosclerosis
Authors: Matsushima Yoshihiro , Kawano Hiroaki , Koide Yuji , Baba Takeshi , Toda Genji , Seto Shinji , Yano Katsusuke 
Published: June 2007

AbstractBackground: Carotid intima‐media thickness (IMT), pulse wave velocity (PWV), and the ankle brachial index (ABI) are widely used noninvasive modalities for evaluating atherosclerosis.Hypothesis: The aim of this study was to determine the relationship of carotid IMT, PWV, and ABI with the severity of coronary artery disease (CAD), expressed as the Gensini score, and the presence of coronary risk factors.Methods: We examined 205 consecutive patients (mean age 65 ± 12 years) who were clinically suspected of having CAD and were scheduled to undergo coronary angiography. Carotid intima‐media thickness, brachial‐ankle PWV (baPWV), and ABI were measured in all subjects before they underwent coronary angiography.Results: Of the 205 patients, 124 patients were diagnosed as having CAD based on the presence of > 50% stenosis in a major coronary artery; the remaining 81 patients did not have CAD. A relatively good correlation was obtained between carotid IMT and the Gensini score (R = 0.411, p < 0.0001), whereas baPWV correlated only weakly with the Gensini score (R = 0.203, p = 0.0035), and ABI did not correlate with it. A multiple regression analysis revealed that the Gensini score correlated significantly and independently with age, male gender, and carotid IMT.Conclusions: Of the three noninvasive methods, carotid IMT may be more useful for determining coronary artery atherosclerosis than baPWV or ABI.
Critical pathways in the emergency department improve treatment modalities for patients with ST‐elevation myocardial infarction in a European hospital
Authors: Pelliccia Francesco , Cartoni Domenico , Verde Monica , Salvini Paolo , Mercuro Giuseppe , Tanzi Pietro 
Published: June 2007

AbstractBackground:The use of protocols for patients with ST‐elevation myocardial infarction (MI) is growing, but no definite conclusion regarding the value of critical pathways in Europe has been drawn.Hypothesis:The aim of this study was to investigate the impact of critical pathway on processes of care and outcome for patients presenting to the emergency department (ED) of a large urban European hospital because of possible ST‐elevation MI.Methods:Critical pathways for management of acute chest pain at our ED were developed in 1998 and have been revised every year. Accordingly, the records of all patients referred in 1997 to the ED because of chest pain (before pathway implementation) and in 2001 (after last pathway revision) were reviewed. An ST‐elevation MI was diagnosed at ED in 520 of 5,066 (10.3%) patients with chest pain in 1997, and in 452 of 4,843 (9.3%) patients with chest pain in 2001. Patients were managed according to the ED cardiologists' decisions in 1997, whereas they entered the pathways for ST‐elevation MI in 2001, with predefined criteria for diagnosis, thrombolysis, percutaneous coronary intervention, and admission to the coronary care unit.Results:Comparison of treatment modalities disclosed that more patients were given thrombolysis in 1997 (49 vs. 16%, p < 0.05), whereas in 2001 more patients were sent to primary angioplasty (63 vs. 11%, p < 0.05). Also in 2001, patients more often received aspirin (90 vs. 61%, p < 0.05) and intravenous beta blockers (60 vs. 35%, p < 0.05) soon after arrival at the ED. Comparison between 1997 and 2001 revealed that admission rates to the coronary care unit (69 vs. 78%, NS) and cardiac wards were similar (19 vs. 10%, NS). Conversely, compared with 1997, patients hospitalized in 2001 had a shorter length of stay (12 ± 5 vs. 18 ± 6 days, p < 0.05), as well as fewer major adverse coronary events (21 vs. 30%, p < 0.05) and lower all‐cause in‐hospital mortality (12 vs. 20%, p < 0.05). The quality of care indicators improved with time, as door‐to‐electrocardiogram interval (10 ± 6 vs. 19 ± 9 min, p < 0.05), door‐to‐needle time (25 ± 10 vs. 35 ± 10 min, p < 0.05), and door‐to‐balloon interval (70 ± 15 vs. 99 ± 20 min, p < 0.05) were shorter in 2001 than in 1997.Conclusions:A critical pathway for ST‐elevation MI at the ED increases the use of evidence‐based treatment strategies and improves outcome and quality of care of patients presenting to a European hospital because of acute chest pain.
Cardiac troponins T and I in patients with end‐stage renal disease: The relation with left ventricular mass and their prognostic value
Authors: Abaci Adnan , Ekici Eyup , Oguzhan Abdurrahman , Tokgoz Bulent , Utas Cengiz 
Published: June 2007

AbstractBackground:Cardiac troponins are frequently elevated in patients with end‐stage renal disease (ESRD) in the absence of acute myocardial ischemia. The cause and prognostic value of cardiac troponin elevations in such patients are controversial.Hypothesis:The aims of this study were (1) to define the incidence of cTnT and cTnI elevations in patients with ESRD, (2) to evaluate the relationship between troponin elevations and leftventricularmass index (LVMI), and (3) to evaluate the prognostic value of elevations in cTnT and cTnI prospectively.Methods:We included 129 patients with ESRD (71 men, age 44 ± 16 years) with no clinical evidence of coronary artery disease. All patients underwent cardiac examinations, including medical history, physical examination, electrocardiogram, andtransthoracic echocardiography. Left ventricular mass index was calculated and all patients were followed for 2 years.Results:The cTnT concentration was > 0.03–0.1 ng/ml in 27 (20.9%) and > 0.1 ng/ml in 27 (20.9%) of the 129 patients. The cTnI concentration was > 0.5 ng/ml in 31 (24%) of 129 patients. Multiple logistic regression analysis identified LVMI (p < 0.001), diabetes (p = 0.001), and serum albumin level (p= 0.009) as a significant independent predictor for elevated cTnT. Left ventricular mass index was the only significant independent predictor for elevated cTnI (p = 0.002). There were 25 (19.4%) deaths during follow‐up. Multivariable analysis showed that elevation of cTnT and cTnI did not emerge as an independent predictor for death. Serum albumin level (p < 0.001) was the strongest predictor of mortality, followed by age (p = 0.002) and LVMI (p = 0.005).Conclusions:Cardiac troponin T and I related significantly to the LVMI. The increased serum concentration of cardiac troponins probably originates from the heart; however, they are not independent predictors for prognosis.
HIV‐1 induced generation of C5a attracts immature dendriticcells and promotes infection of autologous T cells
Authors: Soederholm Anna , Bánki Zoltán , Wilflingseder Doris , Gassner Christoph , Zwirner Joerg , López‐Trascasa Margarita , Falkensammer Barbara , Dierich Manfred P. , Stoiber Heribert 
Published: June 2007

AbstractFor the recruitment of dendritic cells (DC) to the site of infection, DC express several sensors for danger signals, such as receptors for C5a. This anaphylatoxin is generated upon complement activation. As HIV‐1 triggers the complement cascade, we determined whether C5a is generated by the virus and tested the functional activity of C5a in migration and infection assays. The immature (i)DC responded in migration assays to recombinant C5a and native C5a, which was generated in situ upon activation of the complement system by HIV‐1. In combined migration and infection assays, a C5a‐dependent enhancement of HIV‐1 infection in DC‐T cell cocultures was observed. These results indicate that HIV induces generation of C5a and thereby attracts iDC, which in turn promote the productive infection of autologous primary T cells.
Synthesis and Coordination Behavior of Symmetrical Tetraamine Phosphinic Acids
Authors: Kubíček Vojtěch , Řehoř Ivan , Havlíčková Jana , Kotek Jan , Císařová Ivana , Hermann Petr , Lukeš Ivan 
Published: June 2007

AbstractTwo new tetraamine ligands, bis[N‐(2‐aminoethyl)aminomethyl]phosphinic acid (Hen2p) and bis[N‐(3‐aminopropyl)aminomethyl]phosphinic acid (Hpn2p), were synthesized from the corresponding diaminoalkanes and bis(chloromethyl)phosphinic acid. Their acid–base properties and complexation with Cu2+, Ni2+, and Zn2+ ions were studied by potentiometric titrations. Different chain lengths of the ligands result in significantly different coordination abilities. The five‐membered chelate ring of Hen2p leads to a higher stability of its complexes. In comparison with tetraamines having the same number of the bridging atoms separating the amino groups, the presence of the phosphinic acid moiety decreases the basicity of the amine groups, and consequently, the stability of their complexes. Several solid‐state structures were determined by X‐ray diffraction analysis. Four nitrogen atoms coordinate the Cu2+ or Zn2+ ion in a square‐planar fashion, whereas the phosphinic acid group is not coordinated or acts as a bridging unit between neighboring metal ions. The unexpectedly high stability of the Ni2+/Hpn2p complex can be explained by the possible presence of a tetramer in solution as was found in the solid state.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Acceleration response modification factors for nonstructural components attached to inelastic moment‐resisting frame structures
Authors: Sankaranarayanan Ragunath , Medina Ricardo A. 
Published: June 2007

AbstractA statistical analysis of the peak acceleration demands for nonstructural components (NSCs) supported on a variety of stiff and flexible inelastic regular moment‐resisting frame structures with periods from 0.3 to 3.0 s exposed to 40 far‐field ground motions is presented. Peak component acceleration (PCA) demands were quantified based on the floor response spectrum (FRS) method without considering dynamic interaction effects. This study evaluated the main factors that influence the amplification or decrease of FRS values caused by inelasticity in the primary structure in three distinct spectral regions namely long‐period, fundamental‐period, and short‐period region. The amplification or decrease of peak elastic acceleration demands depends on the location of the NSC in the supporting structure, periods of the component and building, damping ratio
of the component, and level of inelasticity of the supporting structure. While FRS values at the initial modal periods of the supporting structure are reduced due to inelastic action in the primary structure, the region between the modal periods experiences an increase in PCA demands. A parameter denoted as acceleration response modification factor (Racc) was proposed to quantify this reduction/increase in PCA demands. Copyright © 2007 John Wiley & Sons, Ltd.
A three‐dimensional non‐hydrostatic vertical boundary fitted model for free‐surface flows
Authors: Badiei Peyman , Namin Masoud M. , Ahmadi Afshin 
Published: June 2007

AbstractA non‐hydrostatic finite volume model is presented to simulate three‐dimensional (3D) free‐surface flows on a vertical boundary fitted grid system. The algorithm, which is an extension to the previous two dimensional vertical (2DV) model proposed by Ahmadi et al. (Int. J. Numer. Meth. Fluids 2007; 54(9):1055–1074), solves the complete 3D Navier–Stokes equations in two major steps based on projection method. First, by excluding the pressure terms in momentum equations, a set of advection–diffusion equations are obtained. In the second step, the continuity and the momentum equations with the remaining pressure terms are solved which yields a block tri‐diagonal system of equations with pressure as the
unknown. In this step, the 3D system is decomposed into a series of 2DV plane sub‐systems which are solved individually by a direct matrix solver. Iteration is required to ensure convergence of global 3D system. To minimize the number of vertical layers and subsequently the computational cost, a new top‐layer pressure treatment is proposed which enables the model to simulate a range of surface waves using only 2–5 vertical layers. Copyright © 2007 John Wiley & Sons, Ltd.
Mathematical Modelling of Proton‐Conducting Solid Oxide Fuel Cells and Comparison with Oxygen‐Ion‐Conducting Counterpart
Authors: Ni M. , Leung M. K. H. , Leung D. Y. C. 
Published: June 2007

AbstractProton‐conducting solid oxide fuel cells (H‐SOFC), using a proton‐conducting electrolyte, potentially have higher maximum energy efficiency than conventional oxygen‐ion‐conducting solid oxide fuel cells (O‐SOFC). It is important to theoretically study the current–voltage (J–V) characteristics in detail in order to facilitate advanced development of H‐SOFC. In this investigation, a parametric modelling analysis was conducted. An electrochemical H‐SOFC model was developed and it was validated as the simulation results agreed well with experimental data published in the literature. Subsequently, the analytical comparison between H‐SOFC and O‐SOFC was made to evaluate how the use of different electrolytes could affect the SOFC performance. In addition to different ohmic overpotentials at the electrolyte, the concentration overpotentials of an H‐SOFC were prominently different from those of an O‐SOFC. H‐SOFC had very low anode concentration overpotential but suffered seriously from high cathode concentration overpotential. The differences found indicated that H‐SOFC possessed fuel cell characteristics different from conventional O‐SOFC. Particular H‐SOFC electrochemical modelling and parametric microstructural analysis are essential for the enhancement of H‐SOFC performance. Further analysis of this investigation showed that the H‐SOFC performance could be enhanced by increasing the gas transport in the cathode with high porosity, large pore size and low tortuosity.