bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlling the Duality of the Mechanism in Liquid‐Phase Oxidation of Benzyl Alcohol Catalysed by Supported Au–Pd Nanoparticles
Authors: Sankar Meenakshisundaram , Nowicka Ewa , Tiruvalam Ramchandra , He Qian , Taylor Stuart H. , Kiely Christopher J. , Bethell Donald , Knight David W. , Hutchings Graham J. 
Published: April 2011

AbstractIn the solvent‐free oxidation of benzyl alcohol to benzaldehyde using supported gold–palladium nanoparticles as catalysts, two pathways have been identified as the sources of the principal product, benzaldehyde. One is the direct catalytic oxidation of benzyl alcohol to benzaldehyde by O2, whereas the second is the disproportionation of two molecules of benzyl alcohol to give equal amounts of benzaldehyde and toluene. Herein we report that by changing the metal oxide used to support the metal–nanoparticles catalyst from titania or niobium oxide to magnesium oxide or zinc oxide, it is possible to switch off the disproportionation reaction and thereby completely stop the toluene formation. It has been observed that the presence of O2 increases the turnover number of this disproportionation reaction as compared to reactions in a helium atmosphere, implying that there are two catalytic pathways leading to toluene.
Molecular Recognition at the Active Site of Catechol‐O‐methyltransferase (COMT): Adenine Replacements in Bisubstrate Inhibitors
Authors: Ellermann Manuel , Paulini Ralph , Jakob‐Roetne Roland , Lerner Christian , Borroni Edilio , Roth Doris , Ehler Andreas , Schweizer W. Bernd , Schlatter Daniel , Rudolph Markus G. , Diederich François 
Published: April 2011

AbstractL‐Dopa, the standard therapeutic for Parkinson’s disease, is inactivated by the enzyme catechol‐O‐methyltransferase (COMT). COMT catalyzes the transfer of an activated methyl group from S‐adenosylmethionine (SAM) to its catechol substrates, such as L‐dopa, in the presence of magnesium ions. The molecular recognition properties of the SAM‐binding site of COMT have been investigated only sparsely. Here, we explore this site by structural alterations of the adenine moiety of bisubstrate inhibitors. The molecular recognition of adenine is of special interest due to the great abundance and importance of this nucleobase in biological systems. Novel bisubstrate inhibitors with adenine replacements were developed by structure‐based design and synthesized using a nucleosidation protocol introduced by Vorbrüggen and co‐workers. Key interactions of the adenine moiety with COMT were measured with a radiochemical assay. Several bisubstrate inhibitors, most notably the adenine replacements thiopyridine, purine, N‐methyladenine, and 6‐methylpurine, displayed nanomolar IC50 values (median inhibitory concentration) for COMT down to 6 nM. A series of six cocrystal structures of the bisubstrate inhibitors in ternary complexes with COMT and Mg2+ confirm our predicted binding mode of the adenine replacements. The cocrystal structure of an inhibitor bearing no nucleobase can be regarded as an intermediate along the reaction coordinate of bisubstrate inhibitor binding to COMT. Our studies show that solvation varies with the type of adenine replacement, whereas among the adenine derivatives, the nitrogen atom at position 1 is essential for high affinity, while the exocyclic amino group is most efficiently substituted by a methyl group.
Efficient Copper‐Catalyzed Synthesis of Poly‐N‐Heterocycles Containing Amino Acid Residues
Authors: Liu Tao , Wang Ruji , Yang Haijun , Fu Hua 
Published: April 2011

AbstractAn efficient copper‐catalyzed method has been developed for the synthesis of poly‐N‐heterocycles containing amino acid residues. The protocol uses readily available 2‐halobenzamides containing amino acids and their methyl esters, substituted phenylacetonitriles, and malononitrile as the starting materials and the reactions were performed well under mild conditions. The method should provide a novel and useful strategy for synthesis of N‐heterocyclic compounds.
Simultaneous Drug‐Eluting and Bare‐Metal Stent Implantation: Long‐Term Clinical Outcome and Findings of Clinically Indicated Coronary Angiography
Authors: Alexopoulos Dimitrios , Xanthopoulou Ioanna , Karantalis Vasileios , Mitropoulou Georgia , Damelou Anastasia , Davlouros Periklis 
Published: April 2011

AbstractBackground:Simultaneous drug‐eluting stent (DES) and bare‐metal stent (BMS) implantation is occasionally employed in clinical practice, but its long‐term clinical and angiographic outcome is not clear.Hypothesis:We aimed to describe the long‐term clinical outcome and the findings of clinically indicated coronary angiography in patients subjected to simultaneous DES and BMS implantation (“hybrid stenting”).Methods:We identified 236 patients (mean age 62.9 ± 11.4 years, 76.7% men) who had undergone percutaneous coronary intervention with at least 1 DES and 1 BMS. At a median follow‐up of 42 months (range, 6–89 months) available in 222 patients, 13 (5.9%) patients died from cardiac causes, 13 (5.9%) experienced nonfatal acute myocardial infarction, and 24 (10.8%) experienced unstable angina. Clinically indicated repeat coronary angiography was performed in 64 patients (28.8%).Results:Thirty‐one patients (14%) had target lesion revascularization (TLR). The DES demonstrated lower TLR rates (15.9% vs 36.9%, P = 0.002) and lower late loss (0.44 ± 0.5 mm vs 0.68 ± 0.7 mm, P = 0.009) compared with BMS. Use of DES was independently associated with lower risk for binary restenosis (hazard ratio [HR]: 0.41, 95% confidence interval [CI]: 0.19–0.89, P = 0.03) and TLR (HR: 0.26, 95% CI: 0.12–0.54, P<0.001).Conclusions:Although a hybrid stenting strategy demonstrates a reasonable long‐term prognosis even in high‐risk patients, DES have a better angiographic outcome compared with BMS under the influence of common patient‐related restenosis risk factors. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Long‐Term Outcomes of Sirolimus‐Eluting Stents vs Paclitaxel‐Eluting Stents in Unprotected Left Main Coronary Artery Bifurcation Lesions
Authors: Song Pil Sang , Ryu Dong Ryeol , Song Young Bin , Hahn Joo‐Yong , Choi Jin‐Ho , Choi Seung‐Hyuk , Lee Sang Hoon , Hong Kyung Pyo , Park Jeong Euy , Gwon Hyeon‐Cheol 
Published: April 2011

AbstractBackground:The treatment of unprotected left main coronary artery (uLMCA) bifurcation lesions remains challenging.Hypothesis:We hypothesized that the type of drug‐eluting stent would correlate with clinical outcomes for the treatment of uLMCA bifurcation lesions.Methods:One hundred fifteen patients who underwent stent implantation using a provisional T‐stenting technique with sirolimus‐eluting stents (SES) or paclitaxel‐eluting stents (PES) for uLMCA bifurcation lesions were enrolled. A major adverse cardiac event (MACE) was defined as a composite of cardiac death, myocardial infarction, or target lesion revascularization.Results:Ninety‐four patients were treated with SES and 21 patients with PES. Baseline characteristics were similar between the 2 groups. Angiographic follow‐up was performed in 99 (86%) patients. Late loss in the LMCA to the left anterior descending coronary artery was significantly lower in the SES group than in the PES group (0.28 ± 0.54 mm vs 1.03 ± 0.45 mm, P<0.001). One case of stent thrombosis occurred in the SES group. During follow‐up with a median of 712 days, the SES group had a lower MACE compared with the PES group (10.6% vs 28.6%, P = 0.032). Cox proportional hazards models including age, sex, diabetes, acute coronary syndrome, true bifurcation, stenting strategy, and type of drug‐eluting stent used (SES vs PES) demonstrated that stent type was the only predictor of MACE (hazard ratio of PES vs SES: 3.88, 95% confidence interval: 1.29–11.67, P = 0.016).Conclusions:According to the results of the present study, SES may be associated with more favorable outcomes than PES for stenting of uLMCA bifurcation, which should be further studied by larger trials. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Evaluation of Trimetazidine in Angina Pectoris by Echocardiography and Radionuclide Angiography: A Meta‐Analysis of Randomized, Controlled Trials
Authors: Hu Bo , Li Wei , Xu Tao , Chen Tao , Guo Jin 
Published: April 2011

AbstractBackground:The objective of this meta‐analysis was to evaluate the efficacy of the metabolic agent trimetazidine (TMZ) as monotherapy in the treatment of stable angina pectoris, from echocardiography and radionuclide angiography data.Hypothesis:Treatment with TMZ proved to be as effective as other first‐line antianginal agents for coronary patients, and it provided additional efficacy in combination with hemodynamic agents.Methods:A search of the literature published between 1965 and 2008 was performed on the MEDLINE and EMBASE databases. Only randomized, controlled trials were included in this meta‐analysis. Patients had to be treated for at least 2 weeks with data on the following 4 parameters at baseline and at the end of the treatment period: left ventricular ejection fraction (LVEF), LV end‐diastolic volume (LVEDV), LV end‐systolic volume (LVESV), and wall motion score index (WMSI). The quality of the trials was assessed by the Jadad score.Results:Eleven clinical studies meeting our criteria were analyzed. Results showed that TMZ significantly improved LVEF, with a mean increase of 6.88% (95% confidence interval [CI]: 5.50–8.25), and significantly reduced LVESV by 11.58 mL (95% CI: 5.79–17.37) and WMSI by 0.23 (95% CI: 0.07–0.38). Changes in LVEDV were variable. In both the long term and the short term, TMZ can improve LV function. The efficacy was unchanged in patients with diabetes mellitus.Conclusions:This meta‐analysis confirmed the efficacy of TMZ monotherapy in improving LV function compared with placebo. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Aortic and Coronary Artery Dissection During Percutaneous Coronary Intervention: A Case Report and Review Article
Authors: Yarlioglues Mikail , Tasdemir Kutay , Kaya Mehmet Gungor , Kalay Nihat 
Published: April 2011

AbstractCoronary artery dissection is an uncommon but potentially serious complication in percutaneous coronary interventions. We treated a 53‐year‐old female patient with right coronary spasm, which was misdiagnosed as a coronary lesion. The coronary spasm resolved with nitrate administration, but proximal coronary dissection developed during angiography. It progressed anterograde and led to inferior myocardial infarction and severe hemodynamic instability due to right coronary artery occlusion. Percutaneous intervention failed, and it was determined that coronary dissection progressed retrograde, across the truncus of the aorta. Ascending aortic grafting and coronary bypass surgery were performed. The patient recovered and was discharged after 10 days. Close cardiothoracic observation is mandatory in patient evaluation and management. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Assessment of Systolic and Diastolic Function in Asymptomatic Subjects Using Ambulatory Monitoring With Acoustic Cardiography
Authors: Dillier Roger , Zuber Michel , Arand Patricia , Erne Susanne , Erne Paul 
Published: April 2011

AbstractBackground:Adequately recording diastolic heart sounds and systolic time intervals over longer periods is difficult. Thus, information on the circadian variation of these parameters in an ambulatory population is lacking. Moreover, age‐related changes in the prevalence of diastolic heart sounds and measurements of systolic time intervals in an asymptomatic population have not been studied in continuous recordings.Hypothesis:Diastolic heart sounds and systolic time intervals will have age and circadian variations that reflect known changes in cardiac function due to aging and circadian rhythms.Methods:We studied 128 asymptomatic subjects wearing an ambulatory monitor with acoustic cardiography. The recording spanned a mean duration of 14 hours, including sleep. Data were analyzed for the presence of third (S3) and fourth (S4) heart sounds and for systolic time intervals.Results:In these asymptomatic subjects, S3 was significantly more prevalent in those age <40 years than in those age >40 years, and significantly more pronounced during sleep in the younger group. Also, S4 was significantly more prevalent in those age >40 years and significantly more pronounced during sleep in those age >40 years. In contrast, time intervals reflecting systolic function showed less circadian variation and less worsening with age.Conclusions:The nocturnal increase of S4 in the elderly reflects diastolic impairment—likely a result of changes in diastolic filling patterns with increasing age. An S3 after the age of 40 is a relatively uncommon finding and therefore should be a specific sign of cardiac disease. Continuous monitoring of diastolic heart sounds and systolic time intervals is possible using acoustic cardiography. © 2011 Wiley Periodicals, Inc.Patricia Arand, PhD, is an employee of Inovise Medical. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
Insulin Resistance, Inflammation, and Vascular Disease in Nondiabetic Predialysis Chronic Kidney Disease Patients
Authors: Banerjee Debasish , Recio‐Mayoral Alejandro , Chitalia Nihil , Kaski Juan‐Carlos 
Published: April 2011

AbstractBackground:Chronic kidney disease (CKD) is associated with high cardiovascular morbidity and mortality, which is not fully explained by traditional risk factors; hence, the interest in nontraditional risk factors such as inflammation and insulin resistance (IR). Though IR is shown in nondiabetic CKD, its association with vascular disease and inflammation in this population is unknown, and is what this study aims to investigate.Hypothesis:IR and inflammation are related to vascular disease in nondiabetic predialysis CKD patients.Methods:We studied carotid‐artery intima‐media thickness (IMT) and endothelial function (brachial artery flow mediated dilation [FMD]) in 35 nondiabetic predialysis patients with stage 3–5 CKD and 35 age‐ and gender‐matched controls. Insulin resistance was measured using the homeostasis model assessment for insulin resistance score (HOMA‐IR), inflammation by high‐sensitivity CRP (hsCRP), and their relationship with FMD and IMT.Results:Patients with CKD showed reduced FMD (3.34 ± 2.14% vs 5.27 ± 1.78%, P<0.001) and increased IMT (0.78 ± 0.22 mm vs 0.64 ± 0.16 mm, P = 0.003) compared with controls. The CKD patients had a higher HOMA‐IR (2.20 ± 1.08 vs 1.13 ± 0.64, P<0.001) and hsCRP (3.25 ± 5.47 mg/L vs 1.10 ± 1.85 mg/L [median ± interquartile range], P = 0.02). In the study population, HOMA‐IR was directly related to hsCRP. After adjusting for traditional risk factors, high HOMA‐IR and hsCRP were significantly related to decreased FMD (adjusted β = − 0.44, 95% confidence interval [CI]: − 1.55 to − 0.08, P = 0.003 and adjusted β = − 0.51, 95% CI: − 0.51 to − 0.15, P = 0.001) and increased IMT (adjusted β = 0.62, 95% CI: 0.54–1.90, P = 0.001 and adjusted β = 0.43, 95% CI: 0.08–0.57, P = 0.011), respectively.Conclusions:Subjects with systemic inflammation were more insulin‐resistant, and in nondiabetic predialysis CKD, IR and systemic inflammation were independently associated with endothelial dysfunction and atherosclerosis. © 2011 Wiley Periodicals, Inc.Dr. Debasish Banerjee and Dr. Alejandro Recio‐Mayoral are joint first authors. This study has been supported by grants awarded by the Spanish Society of Cardiology to Dr. A. Recio‐Mayoral and by the St. George's Charitable Foundation to Dr. D. Banerjee. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
Repeat Percutaneous Balloon Mitral Valvotomy vs Mitral Valve Replacement in Patients With Restenosis After Previous Balloon Mitral Valvotomy and Unfavorable Valve Characteristics
Authors: Aslanabadi Naser , Golmohammadi Ali , Sohrabi Bahram , Kazemi Babak 
Published: April 2011

AbstractBackground:Symptomatic mitral restenosis develops in up to 21% of patients after percutaneous balloon mitral valvotomy (PBMV), and most of these patients undergo mitral valve replacement (MVR).Hypothesis:Repeating PBMV (re‐PBMV) might be an effective and less‐invasive treatment for these patients.Methods:Forty‐seven patients with post‐PBMV mitral restenosis and unfavorable valve characteristics were assigned either to re‐PBMV (25 cases; mean age 40.7 ± 11 y, 76% female) or MVR (22 cases; mean age 47 ± 10 y, 69% female) at 51 ± 33 months after the prior PBMV. The mean follow‐up was 41 ± 32 months and 63 ± 30 months for the re‐PBMV and MVR groups, respectively.Results:The 2 groups were homogenous in preoperative variables such as gender, echocardiographic findings, and valve characteristics. Patients in the MVR group were older, with a higher mean New York Heart Association functional class, mean mitral valve area, mitral regurgitation grade, and right ventricular systolic pressure (P = 0.03), and more commonly were in AF. There were 3 in‐hospital deaths (all in the MVR group) and 4 during follow‐up (3 in the MVR group and 1 in the re‐PBMV group). Ten‐year survival was significantly higher in re‐PBMV vs MVR (96% vs 72.7%, P<0.05), but event‐free survival was similar (52% vs 50%, P = 1.0) due to high reintervention in the re‐PBMV group (48% vs 18.1%, P = 0.02).Conclusions:In a population with predominantly unfavorable characteristics for PBMV, short‐ and long‐term outcomes are both reasonable after re‐PBMV with less mortality but requiring more reinterventions compared with MVR. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
Melphalan‐Induced Supraventricular Tachycardia: Incidence and Risk Factors
Authors: Feliz Victor , Saiyad Saleem , Ramarao Sumana M. , Khan Hammad , Leonelli Fabio , Guglin Maya 
Published: April 2011

AbstractBackground:Cardiotoxicity of aggressive chemotherapeutic regimens includes cardiomyopathy and arrhythmias. Although cardiomyopathy is a well‐recognized entity, arrhythmias are poorly studied.Hypothesis:Certain chemotherapeutic regimes are associated with supraventricular arrhythmias, particularly atrial fibrillation.Methods:We retrospectively reviewed the data on patients who received hematopoietic stem cell transplant (bone marrow transplant; BMT) from 1998 to 2005 and developed supraventricular tachycardia (SVT) during the same hospital admission. The Fisher χ2 test and the Student t test were used for comparison of categorical and continuous variables, respectively.Results:During the period of 1998–2005, there were 1221 BMTs, 62 (5.1%) of which were complicated by SVT. Melphalan‐based regimens demonstrated a significantly higher rate of SVT than any other chemotherapy. Out of 438 patients who received melphalan, 48 (11%) developed atrial fibrillation (n = 35) or SVT (n = 13) during the same hospital admission, and 390 did not. Patients with SVT were older, had higher baseline creatinine, larger size of the left atrium, and more cardiac comorbidities. Incidence of SVT was associated with greater length of stay (24.9 ± 8.9 d vs 19.6 ± 5.8 days, P<0.0001), even after adjustment for comorbidities.Conclusions:Supraventricular tachycardia, mostly atrial fibrillation, complicates about 5% of chemotherapeutic treatments used with BMT. Melphalan is the most arrhythmogenic agent, and is associated with SVT in 11% of patients. Development of SVT results in about a 4‐day increase in the length of hospital stay. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
An Environmental Threshold of Soil Test P and Degree of P Saturation of Brazilian Oxisols
Authors: Ghosh Amlan Kumar , Barbosa Joyce , da Silva Ivo Ribeiro 
Published: April 2011

AbstractTo develop P management guidelines for poultry litter application in Oxisols of Brazil, the relationship between water soluble P (WSP), soil test P (STP), and degree of P saturation (DPS) needs to be established. The study examined this relationship in Oxisols of Brazil receiving poultry litter. Soils were analyzed for Mehlich‐1 P (M1‐P), WSP, P fractions, P sorption index (PSI), and P saturation based on Mehlich‐1 extractable P, Al, Fe (DPSM1), and PSI (DPSPSI). Surface water bodies in the catchment area were examined for inorganic and total P. All the surface water bodies in the catchment area of the sampled plots were highly enriched in inorganic and organic P. Enrichment of soil P fractions following poultry litter application followed the order HCl‐bound > NaOH‐bound > NaHCO3‐bound fraction. M1‐P was correlated to labile (NaHCO3‐Pi), and stable P pools (NaOH‐P and HCl‐P) and reflected the cumulative P accumulation in these soils. P saturation indices increased with cumulative P addition and increasing M1‐P. WSP increased with increasing DPS and a change point was noticed at 23% DPSPSI (equivalent to DPSM1 of 16.5%) corresponding to M1‐P of 44.5 mg P kg−1, which could be regarded as threshold for P loss in these soils.
Theoretical and Experimental Studies on the Mechanism of Coloration of Polyimides
Authors: Abe Atsutoshi , Nakano Takashi , Yamashita Wataru , Fukukawa Kenichi , Okazaki Masaki , Tamai Shoji 
Published: April 2011

AbstractThe mechanism of coloration of polyimides is investigated theoretically and experimentally. Since light is considered to be absorbed by polyimides via charge‐transfer excitation, we used the long‐range‐corrected time‐dependent density functional theory recently developed by Tawada et al. [Y. Tawada, T. Tsuneda, S. Yanagisawa, T. Yanai, K. Hirao J. Chem. Phys. 2004, 120, 8425] for the calculation of excitation energies and oscillator strengths. Classical molecular dynamic simulations for packed chain models of polyimides were also performed to analyze the structural information of polyimides in condensed phase. In order to predict the transparency of polyimide film, we developed a theoretical method by combining the results of electronic structure calculations and those of molecular dynamics simulations. We compare our theoretical results with experimental ones and discuss the difference between them. As a result, we clarify the new mechanism of coloration and obtain results for the theoretical UV/Visible spectra.
Inelastic Neutron Scattering Study of PtII Complexes Displaying Anticancer Properties
Authors: Batista de Carvalho Luís A. E. , Marques M. Paula M. , Martin Christine , Parker Stewart F. , Tomkinson John 
Published: April 2011

AbstractThe well‐known platinum(II) chemotherapeutic drugs cisplatin [cis‐(NH3)2PtCl2] and carboplatin [Pt(NH3)2C6O4H6], as well as the analogous transplatin [trans‐(NH3)2PtCl2], were studied by inelastic neutron scattering (INS) spectroscopy, coupled to quantum mechanical methods, and some ancillary work with X‐ray diffraction on powders. An assignment of the experimental spectra was carried out based on the calculated INS transition frequencies and intensities (at the DFT level), thereby achieving a good correspondence between the calculated and observed data. Unusually good‐quality INS spectra were obtained from about 250 mg, which is the smallest sample of a hydrogenous compound for which a successful INS interpretation has been reported. The knowledge of the local configuration of this kind of complexes is essential for an accurate understanding of their activity, which will pave the way for the rational design of novel third‐generation drugs comprising cisplatin‐ and carboplatin‐like moieties.