bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resolution of migraine by transcatheter patent foramen ovale closure with premere occlusion system in a preliminary series of patients with previous cerebral ischemia
Authors: Rigatelli Gianluca , Cardaioli Paolo , Braggion Gabriele , Giordan Massimo , Fabio Dell'Avvocata , Aggio Silvio , Roncon Loris , Chinaglia Mauro 
Published: August 2007

AbstractBackground:Transcatheter closure of PFO with nitinol devices may be problematic in young patients with migraine due the risk of late erosions. Alternative devices with less amount of metal as the last generation devices may be preferable in such cases. We present the results of transcatheter closure of PFO with the last generation Premere Occlusion System device in a preliminary series of young adults with migraine and previous cerebral ischemia.Methods:During a 12‐month period (January 31, 2006 to December 31, 2006) 26 patients (18 female and 8 male, mean age 40 ± 3.7 years) with previous stroke and severe disabling migraine were referred to our center for transcatheter closure of PFO. Migraine disability assessment score (MIDAS) was used to assess MHA incidence and severity. Patients were selected for Premere occlusion system (absence of atrial septal aneurysm and length >15 mm) on the basis of presence/absence of right and left bulging atrial septal aneurysm and length of PFO channel (<15 mm or >15 mm) on transesophageal echocardiography. Transesophageal echocardiography and transcranial Doppler were performed at 1 month, transthoracic echocardiography and cerebral magnetic resonance imaging at 6 and 12 months. Cardiologic and neurological visit was scheduled at 1, 6, and 12 months with MIDAS questionnaire administration.Results:Ten patients (2 males, mean age 32 ± 7.6 years, mean MIDAS score 38.9 ± 5.8) underwent transcatheter PFO closure with the Premere occlusion system. Mean fossa ovalis diameters by ICE measurement was 20.6 ± 3.1 mm. Thus, two 20‐mm and eight 25‐mm Premere devices were implanted. The procedure was successful in all of the patients with no perioperative and in‐hospital complications. After a mean follow‐up of 10.9 ± 5.8 months, all patients were free from migraine symptoms (mean MIDAS score 2.9 ± 1.9) with PFO complete closure in all patients on transesophageal and transcranial Doppler ultrasound.Conclusion:While waiting for larger studies evaluating the impact of new generation devices in curing PFO‐related migraine, this preliminary anecdotal series suggests that the Premere occlusion system may be an effective and safe device for young patients with previous cerebral ischemia and migraine at least in the midterm period. © 2007 Wiley‐Liss, Inc.
Promise and challenges of bioabsorbable stents
Authors: Waksman Ron 
Published: August 2007

AbstractDespite the development and progression of metallic stents, many concerns still remain because of their permanent nature. Although metallic stents are effective in preventing recoil and late restenosis after coronary angioplasty, they continue to have limitations such as stent thrombosis and mismatch of the stent to the vessel size. Thus, the concept of bioabsorbable stents has emerged as an alternative to permanent metal stents. This review will outline concepts, material designs, preclinical, and initial clinical experimental studies with bioabsorbable stents. © 2007 Wiley‐Liss, Inc.
Treatment of severe infrapopliteal vascular disease using a novel atherectomy device: A case report
Authors: Caputo Ronald P. , Ebner Adrian , Garcia Lawrence 
Published: August 2007

AbstractWe report two first in man cases of percutaneous revascularization for severe intrapopliteal arterial disease using the novel PV atherectomy device. © 2007 Wiley‐Liss, Inc.
Anti‐platelet and anti‐thrombotic approaches in patients undergoing percutaneous coronary intervention
Authors: Garg Rajeev , Uretsky Barry F. , Lev Eli I. 
Published: August 2007

AbstractOver the past three decades, there has been a tremendous increase in the use of percutaneous coronary interventions (PCI) for the treatment of patients with atherosclerotic coronary artery disease. However, PCI causes disruption of atherosclerotic plaque and denudation of the endothelium, leading to stimulation of platelet aggregation and activation of the coagulation cascade. Therefore, anti‐platelet and anti‐thrombotic agents have a pivotal role as adjuncts before, during and after PCI, in order to minimize the risk of procedural ischemic complications, such as myocardial infarction, stent thrombosis, and various degrees of myonecrosis. The current article presents a comprehensive review of the evolution of current anti‐platelet and anticoagulation regimens used in the setting of PCI. It starts with a summary of the current perspective of the coagulation process along with platelet activation and aggregation. The review then focuses specifically on individual anti‐platelet and anti‐thrombotic drugs including their mechanism of action and the scientific evidence which led to their use in PCI. Finally, we present summary recommendations from the AHA/ACC guidelines for individual anticoagulant and anti‐platelet regimens given peri‐PCI. © 2007 Wiley‐Liss, Inc.
The AST petal dedicated bifurcation stent: First‐in‐human experience
Authors: Ormiston John , Webster Mark , El‐Jack Seifeddin , McNab Duncan , Simpson Plaumann Stephanie 
Published: August 2007

AbstractThe aim of this first‐in‐human study was to evaluate the feasibility and safety of the novel AST petal side‐access bifurcation stent. Outcomes following percutaneous coronary intervention for bifurcations remain inferior to those of nonbifurcated lesions. Even with drug‐eluting stents, restenosis occurs especially at the side‐branch (SB) ostium. The petal stent uniquely deploys strut elements into the SB, supporting the ostium and carina. The primary endpoint of this 13‐patient prospective registry was in‐hospital major adverse cardiac events (MACE). Secondary end points included acute minimum lumen diameter (MLD) at the SB ostium, lesion success, device success, procedural success, 30‐day MACE, and 4‐month SB ostial MLD. The study lesion was successfully treated in 13 patients with the study stent being successfully implanted in 12. Target lesions were left anterior descending coronary artery in nine subjects, left circumflex in three, and right coronary artery in one. In‐hospital MACE were limited to two non‐Q‐wave myocardial infarctions. In‐stent main branch MLD increased from a mean of 0.63 ± 0.45 mm to 2.61 ± 0.47 mm at the index procedure and for this initial bare metal version of the stent, 4‐month mean MLD measured 1.02 ± 0.42mm and there was target vessel revascularization on two patients. The feasibility of safely deploying this first‐generation petal stent was demonstrated in selected patients with challenging coronary bifurcation lesions. It is a promising platform for drug delivery, with unique scaffolding of the side‐branch ostium. © 2007 Wiley‐Liss, Inc.
Treatment of instent restenosis following stent‐supported renal artery angioplasty
Authors: Zeller Thomas , Rastan Aljoscha , Schwarzwälder Uwe , Mueller Christian , Schwarz Thomas , Frank Ulrich , Bürgelin Karlheinz , Sixt Sebastian , Noory Elias , Beschorner Ulrich , Hauswald Kirsten , Branzan Daniela , Neumann Franz‐Josef 
Published: August 2007

AbstractObjectives:We prospectively studied the long‐term outcome of endovascular treatment of instent renal artery stenosis (IRAS).Background:Restenosis is a considerable drawback of stent‐supported angioplasty of renal artery stenosis especially in small vessel diameters. The appropriate treatment strategy is not yet defined.Patients and Methods:During a 10‐year period 56 consecutive patients (65 lesions) with their first IRAS were included in a prospective follow‐up program (mean follow‐up 53 ± 25 months, range 6–102). Primary endpoint of the study was the reoccurrence of IRAS (≥ 70%) after primarily successful treatment of the first IRAS determined by duplex ultrasound.Results:Primary success rate was 100%, no major complication occurred. Nineteen lesions were treated with plain balloon angioplasty (group 1, 30%), 42 lesions with stent‐in‐stent placement (group 2, 65%) using various bare metal balloon expandable stents, and 4 lesions with drug‐eluting stent angioplasty (group 3, 6%). During follow‐up, overall 21 lesions (32%) developed reoccurrence of IRAS: n = 7/19 in group 1 (37%), n = 14/42 in group 2 (33%), and n = 0/4 in group 3 (0%; P = 0.573). Reoccurrence of IRAS was more likely to occur in smaller vessel diameters than in larger ones [3–4mm: 4/7 (57%); 5 mm: 11/26 (42%); 6 mm: 5/25 (20%); 7 mm: 1/7 (14%), P = 0.088]. Multivariable analysis found bilateral IRAS and IRAS of both renal arteries of the same side in case of multiple ipsilateral renal arteries as independent predictors for reoccurrence of IRAS.Conclusion:Treatment of IRAS is feasible and safe. The data demonstrate a nonsignificant trend towards lower restenosis with restenting of IRAS versus balloon angioplasty of IRAS. Individual factors influence the likelihood of reoccurrence of IRAS. © 2007 Wiley‐Liss, Inc.
Interventional stroke therapy: Current state of the art and needs assessment
Authors: White Christopher J. , Cates Christopher U. , Cowley Michael J. , Weiner Bonnie H. , Carpenter Jeffrey S. , Hopkins L. Nelson , Jaff Michael R. , Ramee Stephen R. , Rymer Marilyn M. , Wholey Mark H. 
Published: August 2007

AbstractThe primary therapeutic strategy for ischemic stroke, as for MI patients, is early reperfusion. Improvement in stroke treatment will require dedicated stroke centers to emulate MI quality indicators such as minimizing the “door‐to‐balloon time”. A critical element in achieving this goal will be organizing the existing multidisciplinary pool of carotid interventionalists to provide the endovascular component of the acute care for ischemic stroke patients. © 2007 Wiley‐Liss, Inc.
Reproductive Accuracy of Generic Omega Parameter Safety Valve Two Phase Critical Mass Flow Models Based on Water and Refrigerant R‐134a Data
Authors: Derlien H. , Friedel L. 
Published: August 2007

AbstractThe modified Omega method included in ISO/FDIS 4126‐10 provides the highest accuracy compared to other modified models frequently used in practice and academia. At the same time, it allows for an exceptionless oversizing of the necessary relief area under all test conditions. Nevertheless, the average or statistical reproductive accuracy is characterized by an unacceptably high logarithmic scatter of about 80 % for fluid dynamic critical steam/water and two‐phase refrigerant R‐134a flow. When applying the method to sizing situations with predicted mass flow qualities in excess of 1 % an acceptably modest oversizing is maintained.
Predicting Separation of Lower Hydrocarbon from Natural Gas by a Nano‐Porous Membrane using Capillary Condensation
Authors: Ahmad F. , Mukhtar H. , Man Z. , Dutta B. K. 
Published: August 2007

AbstractIn the present work, the potential of a nano‐porous membrane for predicting the separation of lower hydrocarbons from natural gas by capillary condensation was explored. While a gas permeates through a capillary at a suitable pressure, the adsorbed layer may attain a thickness enough to fill the entire membrane pore. Poiseuille flow of the condensed phase follows. Our computed results have established that for a passage through a nano‐porous membrane, gas having lower condensation pressure condenses in the pores at a pressure which is about an order of magnitude lower than its vapor pressure at the concerned temperature. In the case of propane/methane and butane/methane binary mixtures, propane and butane are preferentially condensed and permeation rates up to 700 g mol/m2 s bar for propane and 600 g mol/m2 s bar for butane have been achieved at a temperature lower than the critical temperature of the permeating species and higher than the critical temperature of the non‐permeating species. Since methane has a much lower critical temperature than both propane and butane, it gets physically dissolved in the condensed phase of propane, butane in the case of propane/methane and butane/methane binary mixtures, respectively. An equation of state (EOS) approach has been adopted to calculate the fugacity of methane in the gas, as well as in the condensed phase, in order to estimate its solubility. The Peng‐Robinson equation of state was used. Computation of the separation factor for methane/propane and methane/butane was performed over a wide range of temperature, pressure, and gas composition. The separation factor which is expectedly a function of these variables ranged from 0.3–75 for methane/propane and 0.7–140 for methane/butane binary mixtures. It has been established that an acceptable degree of separation is achievable at moderate pressure and at low temperature for the removal of propane and butane from natural gas. The results have the potential to be used for further refinement and optimization of the process conditions so that this strategy can be exploited for large‐scale removal of lower hydrocarbon from natural gas at a low cost.
Rational Design of MOFs Constructed from Modified Aromatic Amino Acids
Authors: Xie Yu , Yu Zhaopeng , Huang Xiaoying , Wang Zhiyong , Niu Liwen , Teng Maikun , Li Jing 
Published: August 2007

AbstractThree Phe and Tyr derivatives, 2‐amino‐3‐(4‐aminophenyl)‐propionic acid (AAP), 3E‐[5‐(2‐amino‐2‐carboxyethyl)‐2‐methoxyphenyl]‐acrylic acid (AMPA) and 3‐(4‐aminophenyl)‐2‐(carboxymethyl‐amino)‐propionic acid (ACP) have been chosen as the ligands to construct four kinds of novel metal‐organic frameworks (MOFs) (five structures). These structures are, [CdII{(R)‐AAP}(Py)(H2O)]⋅(ClO4), (R)‐1; [CdII{(S)‐AAP}(H2O)2]⋅(ClO4), (S)‐2; [Zn2II{(R,S)‐AMPA}(H2O)], (R,S)‐3; [Zn2II{(R)‐ACP}(Py)3]⋅(ClO4)2, (R)‐4; and the inversion twin of (R)‐1. Rational design to adjust the “depth” and the “width” of ligands can mediate the size and the shape of the grids of these 2D layers. Additionly, among these compounds, three pure chiral coordination polymers are obtained, owing to the inducement of chirality by the modified amino acids. This property makes them potential NLO materials.
Platinum‐Catalyzed Multistep Reactions of Indoles with Alkynyl Alcohols
Authors: Bhuvaneswari Sivakolundu , Jeganmohan Masilamani , Cheng Chien‐Hong 
Published: August 2007

AbstractPtCl2 effectively catalyzes the multistep reaction of N‐methyl indole (1 a) with pent‐3‐yn‐1‐ol (2 a) in THF at room temperature for 2 h to give indole derivative 3 a, which contains a five‐membered cyclic ether group at C3 in 93 % yield. Under similar reaction conditions, various substituted N‐methyl indoles 1 b–h and indole (1 i) reacted efficiently with 2 a to afford the corresponding indole derivatives 3 b–h and 3 i in 48–91 and 72 % yields. The results showed that N‐methyl indoles with electron‐donating substituents were more reactive affording higher product yields than those with electron‐withdrawing groups. Likewise, various substituted but‐3‐yn‐1‐ols 2 b–e and other longer chain alkynyl alcohols 2 f–i also underwent a cyclization–addition reaction with N‐methyl indole (1 a) to provide the corresponding cyclization–addition products 3 j–m and 3 a, 3 j, and 3 n–o in good to excellent yields. The present platinum‐catalyzed cyclization–addition reaction can be further extended into N‐methyl pyrrole. Mechanistically, the catalytic reaction proceeds by an intramolecular hydroalkoxylation of alkynyl alcohol to afford cyclic enol ether followed by the addition of the CH bond of indole to the unsaturated moiety of cyclic enol ether providing the final product. Experimental evidence to support this proposed mechanism is provided.
Iterative Synthesis of Spacered Glycodendrons as Oligomannoside Mimetics and Evaluation of Their Antiadhesive Properties
Authors: Heidecke Christoph D. , Lindhorst Thisbe K. 
Published: August 2007

AbstractDendrimer chemistry is an attractive concept for mimicry of the highly branched character of the bioactive carbohydrates found as part of a cell's sugar coat, called the glycocalyx. Glycodendrimers have thus been used to study biological processes occurring on cell surfaces, such as bacterial adhesion. This paper details a new approach in glycodendrimer synthesis, in which a 3,6‐diallylated carbohydrate is utilised as core molecule, hydroboration–oxidation is the activating step, and glycosylation with branched and unbranched sugar trichloroacetimidates is used for dendritic growth. To obtain pure dendritic pseudo‐tri‐ and ‐heptasaccharides in good yields, radical addition of mercaptoethanol to peripheral double bonds was also evaluated with great success. A collection of six new hyperbranched glycodendrons was tested for their potential as inhibitors of type 1 fimbriae‐mediated bacterial adhesion in an ELISA and the results were interpreted with regard to sugar valency and spacer characteristics.
Synthesis and Metal Complexes of Chiral C2‐Symmetric Diamino–Bisoxazoline Ligands
Authors: Guillemot Geoffroy , Neuburger Markus , Pfaltz Andreas 
Published: August 2007

AbstractA synthetic route to tetradentate chiral N4 ligands has been developed with the aim to study the potential of corresponding iron and manganese complexes as catalysts for enantioselective epoxidation. These ligands, which contain two oxazoline rings and two trialkylamino groups as coordinating units, are readily prepared in enantiomerically pure form by the reaction of chiral 2‐chloromethyloxazolines with achiral N,N′‐dimethylethane‐1,2‐diamine or chiral (R,R)‐N,N′‐dimethylcyclohexane‐1,2‐diamine. The ligands derived from N,N′‐dimethylethane‐1,2‐diamine reacted with anhydrous metal halides MnCl2 and FeCl2 in a stereoselective manner to give octahedral mononuclear complexes that have the general formula Δ‐[(L)MCl2]. In contrast, the ligands derived from N,N′‐dimethylcyclohexane‐1,2‐diamine formed complexes with different coordination modes depending on the diastereomer employed: in one case the metal ion was found to be pentacoordinate, in the other case a hexacoordinated complex was observed. The structure of a series of Fe and Mn complexes was determined by X‐ray analysis. The coordination chemistry of these ligands was further studied by X‐ray and NMR analyses of the diamagnetic isostructural complexes [(L)ZnCl2]. Analogous ionic complexes, which were prepared by removing chloride with silver trifluoromethanesulfonate or hexafluoroantimonate, were tested as catalysts for the epoxidation of olefins.
A Spectroscopic Study of the Reduction of Geometrically Restrained Viologens
Authors: Benniston Andrew C. , Harriman Anthony , Li Peiyi , Rostron James P. , Harrington Ross W. , Clegg William 
Published: August 2007

AbstractA small series of N,N′‐dimethyl‐4,4′‐bipyridinium dication derivatives (commonly known as viologens) has been synthesized and fully characterized; a short dialkoxy tether attached at the 3,3′‐positions is used to alter the central dihedral angle. These angles were determined by both single‐crystal X‐ray diffraction and by computational studies made for the dication, radical cation, and neutral species in a solvent reservoir. The dihedral angle derived for the dication controls the first reduction potential, whereas the geometry of the resultant π‐radical cation determines the magnitude of the second reduction potential. The optical absorption spectra recorded for the various species, and especially those of the radical cations, and the EPR spectral parameters of the π‐radical cations also depend on the molecular geometry. In particular, the central dihedral angle influences the spin density distribution around the aromatic nucleus and, by way of comparison to the parent viologen, it has been possible to resolve the angle dependence from the inherent inductive effect of the strap. These results are considered in terms of the degree of electronic communication between the two aromatic rings, as controlled by the length of the tether.
Porous Metal Oxides as Gas Sensors
Authors: Tiemann Michael 
Published: August 2007

AbstractSemiconducting metal oxides are frequently used as gas‐sensing materials. Apart from large surface‐to‐volume ratios, well‐defined and uniform pore structures are particularly desired for improved sensing performance. This article addresses the role of some key structural aspects in porous gas sensors, such as grain size and agglomeration, pore size or crack‐free film morphology. New synthesis concepts, for example, the utilisation of rigid matrices for structure replication, allow to control these parameters independently, providing the opportunity to create self‐diagnostic sensors with enhanced sensitivity and reproducible selectivity.
Improving sensitivity in chiral supercritical fluid chromatography for analysis of active pharmaceutical ingredients
Authors: Helmy Roy , Biba Mirlinda , Zang Jia , Mao Bing , Fogelman Kimber , Vlachos Vaso , Hosek Paul , Welch Christopher J. 
Published: August 2007

AbstractDespite its status as the preferred method for routine enantiopurity analysis in pharmaceutical research, supercritical fluid chromatography (SFC) has historically been unsuited for the accurate and precise measurements required for release testing of active pharmaceutical ingredients (APIs) under current good manufacturing processes (cGMPs). Insufficient signal to noise, as compared to HPLC, has heretofore been the major limitation of the chiral SFC approach. We herein describe an investigation into the fundamental limitations and sources of noise in the SFC approach, identifying thermal, electronic, and mechanical sources of noise within the flow cell as key parameters contributing to reduced sensitivity. A variety of instrument modifications are explored, ultimately leading to the development of a new and improved flow cell and other instrument modifications that allow suitable sensitivity and accuracy to carry out GMP release testing for enantiopurity analysis using SFC. Chirality, 2007. © 2007 Wiley‐Liss, Inc.
Enantioselective analysis of citalopram and demethylcitalopram in human and rat plasma by chiral LC‐MS/MS: Application to pharmacokinetics
Authors: Rocha Adriana , Marques Maria P. , Coelho Eduardo B. , Lanchote Vera L. 
Published: August 2007

AbstractCitalopram (CITA) is available as a racemic mixture and as a pure enantiomer. Its antidepressive action is related to the (+)‐(S)‐CITA and to the metabolite (+)‐(S)‐demethylcitalopram (DCITA). In the present investigation, a method for the analysis of CITA and DCITA enantiomers in human and rat plasma was developed and applied to the study of pharmacokinetics. Plasma samples (1 ml) were extracted at pH 9.0 with toluene:isoamyl alcohol (9:1, v/v). The CITA and DCITA enantiomers were analyzed by LC‐MS/MS on a Chiralcel® OD‐R column. Recovery was higher than 70% for both enantiomers. The quantification limit was 0.1 ng/ml, and linearity was observed up to 500 ng/ml plasma for each CITA and DCITA enantiomer. The method was applied to the study of the kinetic disposition of CITA administered in a single oral dose of 20 mg to a healthy volunteer and in a single dose of 20 mg/kg (by gavage) to Wistar rats (n = 6 for each time). The results showed a higher proportion of the (−)‐(R)‐CITA in human and rat plasma, with S/R AUC ratios for CITA of 0.28 and 0.44, respectively. S/R AUC ratios of DCITA were 0.48 for rats and 1.04 for the healthy volunteer. Chirality, 2007. © 2007 Wiley‐Liss, Inc.