bluuebunny/crossref_metadata_2025 huggingface dataset:
Modification of sandy soil using water‐borne polymer
Authors: Al‐Khanbashi Abdullah , El‐Gamal Maisa
Published: March 2003

A new polymeric system has been applied for structural modification of (noncompactable) sandy soils. The system is based on a water‐borne styrene acrylic polymeric formulation (emulsion) containing varying amounts of solid polymer. The present work deals with system optimization and measurements designed to examine the effects of polymer content on hydraulic conductivity and compressive strength. Samples were prepared from prescribed amounts of polymer, water, and sand by using two different preparations methods (mixing and spraying). Measurements of hydraulic conductivity for both sets of samples were conducted in a flexible membrane test apparatus. For the first set of samples, the permeability coefficient of the sand was noted to be reduced 10‐fold (from 10−5 to 10−6 m s−1) upon the incorporation of about 2% polymer. In the second set (samples prepared with the spraying method), the hydraulic conductivity was further reduced to 7.2 × 10−7 at a polymer concentration of about 2%. Stress–strain measurements made on dry cylindrical specimens disclosed remarkable enhancement in the mechanical behavior of the system. For both types of preparation methods, the compressive strength and modulus of elasticity increased linearly with the polymer concentration in the sample. Scanning electron microscopic examination revealed that the dramatic reduction in the permeability and the improved mechanical properties are attributed to the polymer coverage of the sand particles and the development of interconnecting ties between them. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2484–2491, 2003
Graft copolymerization of methyl methacrylate onto rubber‐wood fiber using H2O2 and Fe2+ as an initiator system
Authors: Abu‐Ilaiwi Faraj A. , Ahmad Mansor B. , Ibrahim Nor Azowa , Ab. Rahman Mohamad Zaki , Md. Dahlan Khairul Zaman , Yunus Wan Md. Zin Wan
Published: March 2003

Methyl methacrylate (MMA) was successfully grafted onto rubber‐wood fiber in a free‐radical solution polymerization initiated by ferrous ion and hydrogen peroxide. The effects of the reaction parameters (reaction temperature, reaction period, influence of hydrogen peroxide, ferrous ammonium sulfate, and monomer concentrations) were investigated. The grafting percentage showed dependency on H2O2, Fe2+, and monomer concentrations, as well as reaction temperature and reaction period. The optimum reaction temperature was determined to be about 60°C and the reaction period was 60 min. The optimum concentration of H2O2 was 0.03M and optimum amounts of Fe2+ and MMA were 0.26 mmol and 2.36 × 10−2 mol, respectively. Poly(methyl methacrylate) (PMMA) homopolymer was removed from the graft copolymer by Soxhlet extractor using acetone. The presence of PMMA on the fiber was shown by FT‐IR spectroscopy and gravimetric analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2499–2503, 2003
Blend compatibilizers based on silane‐ and maleic anhydride–modified polyolefins
Authors: Nachtigall Sônia M. B. , Felix Afonso H. O. , Mauler Raquel S.
Published: March 2003

Polypropylene (PP)/polyamide blends were compatibilized with PP modified with vinylsilane or maleic anhydride and ethylene–propylene random (EPR) copolymer modified with maleic anhydride. The thermal behavior, mechanical properties, and morphology of the blends were investigated. Thermal analysis showed that the polyamide crystallization temperatures shifted downward with all compatibilizers, whereas its melting behavior did not change. On the other hand, polypropylene crystallization temperatures shifted upward in all cases, except for blends containing EPR modified with maleic anhydride. Tensile strength and elongation at break increased for blends compatibilized with modified PP. Blends containing up to 7% of EPR modified with maleic anhydride did not show good yield stresses. The morphology of the blends showed a finer dispersion of the polyamide minor phase in the PP matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2492–2498, 2003
Conducting blends of poly(o‐toluidine) and ethylene–propylene–diene terpolymer
Authors: Ghosh Premamoy , Kar Swarnendu B. , Bhattacharyya Sanchita
Published: March 2003

Poly(o‐toluidine) (POT) is an electroactive polymer with poor mechanical and thermal characteristics. We examined the scope for improving such properties by making blends of POT with ethylene–propylene–diene rubber (EPDM). We prepared POT–EPDM blends containing different weight fractions of POT by intimately mixing known volumes of separate solutions of the two polymers (POT in THF and EPDM in toluene). Films of EPDM and POT–EPDM blends in solution were obtained by spreading, solvent evaporation, and film casting techniques. POT, EPDM, and their blends were characterized in solution by ultraviolet‐visible spectroscopy, and the respective dried samples were analyzed by Fourier transform infrared spectroscopy and thermogravimetry. The polymer samples were further analyzed morphologically by scanning electron microscopy, and their tensile strengths were also evaluated. Spectroscopic and thermal studies of the blends indicated some sort of interaction between the two constituent polymers. The direct current electrical conductivity of the blends in increasing order of POT loading (12.5–100%) was in the range 9.9 × 10−5 to 11.6 × 10−2 S cm−1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2550–2555, 2003
Synthesis of polyethylene‐graft‐poly(styrene‐co‐maleic anhydride) and its compatibilizing effects on polyethylene/starch blends
Authors: Park Eun‐Soo , Yoon Jin‐San
Published: March 2003

Low density polyethylene (LDPE) was reacted with benzoyl peroxide (BPO) and 2,2,6,6‐tetramethyl‐l‐piperidinyloxy (TEMPO) to prepare a latent macroinitiator, PE–TEMPO. Little polymer was synthesized when maleic anhydride (MAH) was bulk polymerized in the presence of the PE–TEMPO. However, addition of styrene accelerated the polymerization rate and PE‐grafted‐poly(styrene‐co‐maleic anhyride) [PE‐g‐P(ST‐co‐MAH)] was produced to a high yield. Chemical reaction between MAH units and hydroxyl groups of starch was nearly undetectable in the PE/PE‐g‐P(ST‐co‐MAH)/starch blend system, and the tensile properties of the blend were not enhanced significantly. However, addition of tetrabutyl titanate (TNBT) during the blending procedure improved the tensile properties significantly through an increased interfacial adhesion between the components in the blend system. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2434–2438, 2003
Development of scar markers for the dna‐based detection of the Asian long‐horned beetle, Anoplophora glabripennis (Motschulsky)
Authors: Kethidi Damodar R . , Roden David B. , Ladd Tim R. , Krell Peter J. , Retnakaran Arthur , Feng Qili
Published: March 2003

DNA markers were identified for the molecular detection of the Asian long‐horned beetle (ALB), Anoplophora glabripennis (Mot.), based on sequence characterized amplified regions (SCARs) derived from random amplified polymorphic DNA (RAPD) fragments. A 2,740‐bp DNA fragment that was present only in ALB and not in other Cerambycids was identified after screening 230 random primers in a PCR‐based assay system. Three pairs of nested 22‐mer oligonucleotide primers were designed on the basis of the sequence of this fragment and were used to perform diagnostic PCR. The first pair of primers (SCAR1) amplified a single 745‐bp fragment of ALB DNA, but this did not differentiate ALB from other species. The other two pairs of SCAR primers (SCAR2 and SCAR3) amplified bands of 1,237‐ and 2,720‐bp, respectively, that were capable of differentiating ALB from other closely related non‐native and native Cerambycids, such as A. chinensis (Forster), A. malasiaca (Thomson), A. nobilis (Ganglbauer), Monochamus scutellatus (Say), Plectrodera scalator (Fab), Saperda tridentata (Olivier), and Graphisurus fasciatus (Degeer). The latter two SCAR markers could be amplified using DNA extracted from body parts of ALB such as the wing, the leg, and the antennae as well as tissues from all the developmental stages including the egg, larva, pupa, and adult. These markers were also capable of identifying ALB using the DNA extracted from frass. Our results demonstrate that the SCAR markers we have identified can be used for unambiguously identifying ALB from other closely related Cerambycids using a simple PCR procedure. Arch. Insect Biochem. Physiol. 52:193–204, 2003. © 2003 Wiley‐Liss, Inc.
Trilobite body patterning and the evolution of arthropod tagmosis
Authors: Hughes Nigel C.
Published: March 2003

Preservation permitting patterns of developmental evolution can be reconstructed within long extinct clades, and the rich fossil record of trilobite ontogeny and phylogeny provides an unparalleled opportunity for doing so. Furthermore, knowledge of Hox gene expression patterns among living arthropods permit inferences about possible Hox gene deployment in trilobites. The trilobite anteroposterior body plan is consistent with recent suggestions that basal euarthropods had a relatively low degree of tagmosis among cephalic limbs, possibly related to overlapping expression domains of cephalic Hox genes. Trilobite trunk segments appeared sequentially at a subterminal generative zone, and were exchanged between regions of fused and freely articulating segments during growth. Homonomous trunk segment shape and gradual size transition were apparently phylogenetically basal conditions and suggest a single trunk tagma. Several derived clades independently evolved functionally distinct tagmata within the trunk, apparently exchanging flexible segment numbers for greater regionally autonomy. The trilobite trunk chronicles how different aspects of arthropod segmentation coevolved as the degree of tagmosis increased. BioEssays 25:386–395, 2003. © 2003 Wiley Periodicals, Inc.
Multicenter randomized comparison of direct vs. conventional stenting: The DIRECTO trial
Authors: Ballarino Miguel A. , Moreyra Eduardo , Damonte Aníbal , Sampaolesi Alberto , Woodfield Scott , Pacheco Guillermo , Caballero Gustavo , Picabea Eduardo , Baccaro Jorge , Tapia Luis , Lascano Esteban Ruiz
Published: March 2003

With conventional stenting, predilatation frequently induces dissections that require deploying stents longer than originally planned. To assess whether direct stenting is safe and may prevent dissections and reduce the length of stents implanted, we conducted a randomized study comparing direct (n = 73) and conventional (n = 78) stenting. Direct stenting was successful in 89% of cases, 11% crossed over to predilation without complications. Dissections occurred more frequently in conventional stenting group (10.3% vs. 1.4%; P = 0.034), but did not translate to a significant stent length difference (16.31 ± 7.6 vs. 15.31 ± 5.5; P = NS). Periprocedure creatine kinase elevation and number of balloons utilized were lower with direct stenting. Cathet Cardiovasc Intervent 2003;58:434–440. © 2003 Wiley‐Liss, Inc.
Preliminary experiences using X‐sizer catheter for mechanical thrombectomy of thrombus‐containing lesions during acute coronary syndromes
Authors: Kornowski Ran , Ayzenberg Oded , Halon David A. , Kusniec Fabio , Assali Abid
Published: March 2003

Thrombus‐containing lesions are frequently observed in patients with acute coronary syndromes. These lesions are prone to increased procedural risks, including distal embolization and abrupt closure of the vessel. This preliminary report evaluates if thrombus removal using a new X‐Sizer catheter could reduce thrombotic burden and optimize angioplasty results. Thrombectomy was attempted with the X‐Sizer catheter in 11 patients (age, 59 ± 10 years) undergoing coronary angioplasty with angiographic evidence of intracoronary thrombus. The device uses a helix cutter contained in a 4.5 or 5.5 Fr catheter tip connected to a closed vacuum aspiration system. Procedural outcomes using detailed angiographic analysis and clinical data were obtained from all treated patients. Seven patients (64%) had acute or recent myocardial infarction and four patients (36%) presented with unstable angina. The culprit lesion was located in right coronary, left anterior, vein graft, and circumflex‐marginal in five, three, two, and one patient, respectively. The mean proximal reference diameter was 3.37 ± 0.39 mm and % diameter stenosis was 90% ± 15% prior to thrombectomy and decreased to 72% ± 16% afterward and was 9% ± 10% at the end of the procedure. The TIMI flow increased from 0.8 ± 1.0 to 2.1 ± 0.9 following thrombectomy and the final TIMI grade was 2.9 ± 0.3. Stents were used in 9 of 11 patients. Procedural success was achieved in 10 of 11 patients (91%). No evidence of stent thrombosis was noted among treated patients in hospital and at 30‐day follow‐up. In this preliminary series of patients with angiographic evidence of thrombus, the use of X‐Sizer thrombectomy seems to be feasible and relatively safe, permitting thrombus removal and improved intracoronary flow. Cathet Cardiovasc Intervent 2003;58:443–448. © 2003 Wiley‐Liss, Inc.
Stent angioplasty of severe atherosclerotic ostial renal artery stenosis in patients with diabetes mellitus and nephrosclerosis
Authors: Zeller Thomas , Müller Christian , Frank Ulrich , Bürgelin Karlheinz , Horn Barbara , Schwarzwälder Uwe , Cook‐Bruns Nancy , Neumann Franz‐Josef
Published: March 2003

Atherosclerotic renal artery stenosis (ARAS) may lead to deterioration of renal function or hypertension. The clinical outcome after stent angioplasty of ARAS on renal function and blood pressure control in patients with diabetes and nephrosclerosis is the subject of some controversy. We have analyzed the results of our single‐center experience with stent angioplasty for severe (≥ 70%) ostial ARAS and present here the results of a subgroup analysis of those patients who had diabetes mellitus and nephrosclerosis. From 1996 to 2001, 241 patients underwent stent angioplasty for the treatment of ARAS at our center. Of these, 99 patients had diabetes mellitus (41%) and 176 patients (73%) had nephrosclerosis defined as intrarenal resistance index (RI) ≥ 0.7 diagnosed by duplex ultrasound. All lesions (n = 355) were treated successfully. Mean blood pressure at baseline was comparable and significantly improved immediately after the intervention in all groups (nondiabetics: 102 ± 12 to 93 ± 10 mm Hg; diabetics: 102 ± 14 to 93 ± 11 mm Hg; RI < 0.7: 105 ± 13 to 95 ± 10 mm Hg; RI = 0.7–0.8: 100 ± 12 to 92 ± 10 mm Hg; RI > 0.8: 102 ± 15 to 92 ± 11 mm Hg; P < 0.0001 each). Baseline serum creatinine was not significantly lower in nondiabetics compared to diabetics (1.46 ± 0.9 vs. 1.62 ± 1.2 mg %; P < 0.05) and increased in patients with nephrosclerosis (RI < 0.7: 1.18 ± 0.6 mg %; RI = 0.7–0.8: 1.57 ± 1.1 mg %; RI > 0.8: 1.96 ± 1.6 mg %). Except for patients without nephrosclerosis who had a normal baseline creatinine, serum creatinine decreased significantly in all subgroups during follow‐up. Stent angioplasty of ARAS offers favorable acute and long‐term clinical results for the preservation of the renal function and for blood pressure control in patients with diabetes mellitus and nephrosclerosis. Cathet Cardiovasc Intervent 2003;58:510–515. © 2003 Wiley‐Liss, Inc.
Simultaneous device closure of muscular ventricular septal defect and pulmonary valve balloon dilatation
Authors: Gupta Mamtesh , Juneja Rajnish , Saxena Anita
Published: March 2003

Percutaneous closure of ventricular septal defect and pulmonary valvuloplasty appears to be an attractive modality when compared to surgical treatment for both lesions. We report successful transcatheter closure of muscular ventricular septal defect with pulmonary valve balloon dilation performed simultaneously in a 27‐year‐old woman. Technical considerations in such a setting are being discussed. Cathet Cardiovasc Intervent 2003;58:545–547. © 2003 Wiley‐Liss, Inc.
Eversion endarterectomy complicating radial artery access for left heart catheterization
Authors: Dieter Robert S. , Akef Abdul , Wolff Mathew
Published: March 2003

The use of the radial artery for arterial access for left heart catheterization is gaining popularity. We report the first case of traumatic eversion endarterectomy following the removal of the arterial sheath after the cannulation of the radial artery. The patient has no long‐term vascular compromise of the limb and did not require surgical intervention. Cathet Cardiovasc Intervent 2003;58:478–480. © 2003 Wiley‐Liss, Inc.
Cavernous hemangioma of the foot and antecubital fossa: An alternative therapeutic option
Authors: Baptista Edward G. , Achour Hela , Boccalandro Fernando , Smalling Richard W.
Published: March 2003

We present two cases of recurrent cavernous hemangiomas of the extremities. These conditions were initially treated unsuccessfully with surgical resection. After recurrence, the hemangiomas were treated by percutaneous transcatheter embolization. To the best of our knowledge, this is the first case report of treatment of cavernous hemangioma involving the extremities using an angiographically directed vascular embolization technique. Cathet Cardiovasc Intervent 2003;58:527–531. © 2003 Wiley‐Liss, Inc.
Late thrombosis after gamma‐brachytherapy
Authors: Maehara Akiko , Mintz Gary S. , Weissman Neil J. , Bui Anh B. , Castagna Marco T. , Ajani Andrew E. , Pichard August D. , Satler Lowell F. , Suddath William O. , Kent Kenneth M. , Yang Nathan , Chan Rosanna , White Larry , Waksman Ron
Published: March 2003

Late stent thrombosis (> 30 days after treatment) is a new phenomenon occurring after vascular brachytherapy. We report the analysis of 11 patients with late thrombosis after gamma‐irradiation treatment of in‐stent restenosis. All patients had in‐stent restenosis and angina. Contributing factors to late thrombosis include long stents, small distal vessels, and complex lesion morphology. Cathet Cardiovasc Intervent 2003;58:455–458. © 2003 Wiley‐Liss, Inc.
Acute stent thrombosis after early withdrawal of platelet glycoprotein IIb/IIIa antagonists: Potential rebound prothrombotic effect?
Authors: Angiolillo Dominick Joseph , Sabaté Manel , Fernández‐Ortiz Antonio , Macaya Carlos
Published: March 2003

We report on two cases of acute coronary stent thrombosis after early withdrawal of different competitive inhibitors of the platelet glycoprotein IIb/IIIa receptor, eptifibatide and tirofiban. Differences in pharmacokinetics between different types of glycoprotein IIb/IIIa receptor blockers and a potential rebound prothrombotic effect with the use of these antiplatelet drugs are reviewed. Cathet Cardiovasc Intervent 2003;58:481–484. © 2003 Wiley‐Liss, Inc.
Impact of restenosis and disease progression on clinical outcome after multivessel stenting in diabetic patients
Authors: Loutfi Mohamed , Mulvihill Niall T. , Boccalatte Marco , Farah Bruno , Fajadet Jean , Marco Jean
Published: March 2003

Clinical outcome after percutaneous coronary intervention (PCI) is significantly worse in diabetic patients in comparison to nondiabetic patients. The subset of diabetic patients in the ARTS trial treated with multivessel stenting had the lowest 1‐year event‐free survival. We examined our experience of multivessel PCI in diabetics to assess clinical outcome outside clinical trials and to determine if repeat revascularizations are the result of restenosis or the progression of nontreated disease. Between January 2000 and December 2001, we performed multivessel PCI in 99 diabetic patients. Our group was well matched with those in the ARTS trial, with mean age of 69 ± 8 years, male sex 70%, hypertension 68%, hypercholesterolemia 51%, and mean LV ejection fraction 60%. The mean number of diseased segments treated was 2.8 ± 0.9 and 56% of the patients had three‐vessel disease. There were 2.3 ± 0.6 stents implanted per patient. Target vessels included the LAD in 90%, LCx in 77%, and the RCA in 87% of cases. The in‐hospital MACE rate was 8%, which included eight nonfatal MI but no deaths or repeat revascularizations. After a mean follow‐up of 14 ± 8 months, there were 4 deaths (4%), no further MIs, and 21 (21%) repeat revascularizations (2 CABG; 19 PCI), giving a 1‐year event‐free survival of 67%. There were 18 repeat revascularizations (2 CABG; 16 PCI) for restenosis, but in 9 of the 18 (50%) patients treatment was also required for progression of disease. Three further patients had PCI for symptomatic disease progression without restenosis. Thus, disease progression contributed to 57% of repeat revascularization procedures. The medium‐ and longer‐term success of multivessel PCI in diabetic patients is limited principally by the need for repeat revascularization. However, it is important to realize that these revascularizations are performed not only for restenosis but also for disease progression in more than 50% of patients. Consequently, even if drug‐eluting stent technology can eliminate restenosis, disease progression will continue to impact the clinical outcome of diabetic patients after PCI. Cathet Cardiovasc Intervent 2003;58: 451–454. © 2003 Wiley‐Liss, Inc.
Thrombin injection for treatment of false aneurysms after failed compression therapy in patients on full‐dose antiplatelet and heparin therapy
Authors: Görge Günter , Kunz Thomas
Published: March 2003

The aim of this study was to gauge the effectiveness of thrombin injection after failed manual compression in patients with false aneurysms receiving full‐dose antiplatelet and heparin therapy. In consecutive patients with failed manual compression therapy (ultrasound‐guided manual compression, compression bandage, or both), thrombin was injected under ultrasound guidance. In 23 patients, thrombin was injected into the false aneurysm (100–2,000 units; mean, 895 ± 520 units). All patients were on aspirin (median dose, 100 mg/day), clopidogrel (median dose, 75 mg/day), and either heparin (n = 3) with a partial thromboplastin time (PTT) > 55 sec or weight‐adjusted enoxaparine (0.1 ml per 10 kg; maximum, 1 ml/b.i.d.). Twelve patients had received an i.v. GB IIIb/IIa antagonist 11–72 hr prior to diagnosis of the aneurysm. The mean width of the false aneurysms was 20.8 ± 3.2 mm (range, 8.0–52.0 mm), length 29.7 ± 32.6 mm (range, 9.0–147 mm), and depth 19 ± 9.1 mm (range, 5.1–35.5 mm). Thrombosis after thrombin injection occurred in 21 patients within seconds. One patient required a second injection the next day, one patient underwent surgery. Overall success rate was 96%. No in‐hospital complications occurred. In patients with false aneurysms and failed compression therapy under full‐dose aspirin, clopidogrel, and heparin, selective thrombin injection is highly effective and safe. Cathet Cardiovasc Intervent 2003;58:505–509. © 2003 Wiley‐Liss, Inc.
Transthoracic left ventricular puncture for the assessment of patients with aortic and mitral valve prostheses: The Massachusetts General Hospital experience, 1989–2000
Authors: Walters Darren L. , Sanchez Pedro L. , Rodriguez‐Alemparte Maximo , Colon‐Hernandez Pedro J. , Hourigan Lisa A. , Palacios Igor F.
Published: March 2003

Accurate assessment of suspected prosthetic valve dysfunction is critically important as reoperation carries high risk. Noninvasive methods of hemodynamic assessment of patients with both aortic and mitral mechanical valves continue to be frustrated by the interference created by prosthetic material and direct left ventricular puncture may be required for definitive hemodynamic assessment. We report the hemodynamic and angiographic results and outcomes of 38 consecutive patients with double valve replacement who underwent left ventricular puncture as part of evaluation of possible prosthetic dysfunction. These results were compared with those obtained by noninvasive testing. We found noninvasive assessment alone to be unsatisfactory as measurements of regurgitation and stenosis correlated poorly with those obtained by direct left ventricular puncture. Important information that altered patient management was obtained from invasive assessment in 68% of cases with an acceptable rate of complications. Therefore, hemodynamic and angiographic assessment using transthoracic left ventricular puncture should be entertained in patients with mitral and aortic valve replacement presenting with congestive heart failure and suspected prosthesis dysfunction. Cathet Cardiovasc Intervent 2003;58:539–544. © 2003 Wiley‐Liss, Inc.
Partial anomalous pulmonary venous return: Case report and review of the literature
Authors: AboulHosn Jamil Anis , Criley John Michael , Stringer William W.
Published: March 2003

Isolated partial anomalous pulmonary venous return (APVR) is an uncommon finding. A patient with isolated APVR had pulmonary hypertension without demonstrable left‐to‐right shunting prior to anticoagulant treatment of pulmonary emboli. After anticoagulant therapy, with a fall in pulmonary pressures and resistance to near‐normal levels, left‐to‐right shunting was then detected by oximetry and angiography. The anomaly was visualized on electron beam angiography and confirmed by conventional angiography after anticoagulant therapy. Contrary to the expected obligatory drainage of highly saturated blood associated with APVR, lack of detectable shunting was thought to be due to the obstruction of regional blood due to thromboembolism. Cathet Cardiovasc Intervent 2003;58:548–552. © 2003 Wiley‐Liss, Inc.
Mediastinal and neck hematoma after cardiac catheterization
Authors: Jao Yeun Tarl Fresner Ng , Chen Yi , Fang Ching‐Chang , Wang Shih‐Pu
Published: March 2003

Vascular complications after cardiac catheterization are rare and usually occur at the access sites. However, vessels along the tract of the catheter can also be injured, causing bleeding and hematoma formation. We present a 57‐year‐old male who underwent cardiac catheterization via the radial approach, later developing neck and mediastinal hematoma, which was managed conservatively. This complication has only been reported once in the English literature. Cathet Cardiovasc Intervent 2003;58:467–472. © 2003 Wiley‐Liss, Inc.
Intracoronary fracture and embolization of a coronary angioplasty balloon catheter: Retrieval by a simple technique
Authors: Trehan Vijay , Mukhopadhyay Saibal , Yusuf Jamal , C. Ramgasetty Umamahesh , Mukherjee Samanjoy , Arora Ramesh
Published: March 2003

We report a technique for retrieval of a balloon along with a portion of its shaft from the coronary system using a simple technique that does not involve the use of snare or any other retrieval tool. An additional angioplasty wire and a balloon catheter were used to remove the balloon from the coronary system. Cathet Cardiovasc Intervent 2003;58:473–477. © 2003 Wiley‐Liss, Inc.
Coronary stenting in stable patients: Identification of a low‐risk subgroup that may not require adjunctive antiplatelet therapy
Authors: Mann Tift , Cubeddu Roberto J. , Raynor Laura , Bowen Josie , Schneider Joel E. , Rose Gregory , Cubeddu Gabriela , Ali Raza Jaffar , Jobe Robert Lee , Newman William , Zellinger Micheal
Published: March 2003

The present study prospectively evaluated adjunctive antiplatelet therapy in patients without insulin‐requiring diabetes during elective coronary stenting. Three hundred patients were randomized to one of three treatment groups: clopidogrel pretreatment, adjunctive abciximab, or control. Stenting was successful in 98% and no deaths occurred. Thirty‐day and 1‐year major adverse coronary events (MACEs) was similar in all groups. A subgroup of 109 patients undergoing single‐vessel stenting of type A/B1 lesions with short guidewire times had no postprocedure myocardial infarction or 30‐day MACE. We conclude that patients with these characteristics may safely undergo elective coronary stenting without adjunctive antiplatelet therapy. Cathet Cardiovasc Intervent 2003;58: 459–466. © 2003 Wiley‐Liss, Inc.
Carotid sinus reactions during carotid artery stenting: Predictors, incidence, and influence on clinical outcome
Authors: Leisch Franz , Kerschner Klaus , Hofmann Robert , Steinwender Clemens , Grund Michael , Bibl Dietmar , Leisch Franz A. , Bergmann Hans
Published: March 2003

Carotid sinus reactions (CSR), defined as asystole ≥ 3 sec and hypotension (systolic blood pressure ≤ 90 mm Hg), are frequent events during carotid artery stenting (CAS). Factors predisposing a patient to CSR as well as the impact of CSR on periprocedural complications have not yet been investigated in a prospective manner. The relationship between various clinical, morphologic, and procedural variables and the occurrence of CSR was examined among 105 consecutive patients undergoing successful CAS. After predilatation with a compliant balloon, tubular‐slotted stents were used in all patients. No CSR occurred in 63 (60%) patients, whereas CSR developed in 42 (40%) patients. The most common type of CSR was asystole in combination with short‐term hypotension without clinical symptoms. The most important predictor of CSR was bifurcation location of carotid stenosis (bifurcation > ostial > isolated internal carotid artery; P < 0.001). The other independent predictors were presence of contralateral stenosis (P < 0.02), length of stenosis (P < 0.03), and balloon‐to‐artery ratio (P < 0.02). Occurrence of CSR was unrelated to periprocedural cerebral or cardiovascular complications (7.1% vs. 9.5%; NS). We conclude that CSR occurs frequently (40%) during CAS. Bifurcation location of stenosis is the most important predictor of CSR. CSR does not increase the risk of periprocedural complications. Cathet Cardiovasc Intervent 2003;58:516–523. © 2003 Wiley‐Liss, Inc.
Cutting balloon angioplasty for undilatable venous stenoses causing dialysis graft failure
Authors: Bittl John A. , Feldman Robert L.
Published: March 2003

Dialysis fistulas and bridge grafts frequently develop outflow stenoses in the venous limb, leading to graft failure. The venous stenoses are fibrotic and require percutaneous transluminal angioplasty with high‐pressure balloons. We have encountered venous stenoses in 3 out of 219 hemodialysis patients with graft failure that were undilatable with 6–8 mm high‐pressure balloons inflated to more than 24 atm. In each of these cases, treatment with a 4 mm cutting balloon successfully facilitated subsequent balloon dilation at lower pressures. Cathet Cardiovasc Intervent 2003;58:524–526. © 2003 Wiley‐Liss, Inc.
Percutaneous occlusion of femoral artery pseudoaneurysm by para‐aneurysmal saline injection
Authors: Gehling Gisbert , Ludwig Joseph , Schmidt Andrej , Daniel Werner G. , Werner Dierk
Published: March 2003

The increasing number of coronary interventions and more aggressive anticoagulation is associated with a larger number of iatrogenic femoral pseudoaneurysms (PAs). The majority of PAs clot spontaneously or can be repaired by ultrasound‐guided compression or ultrasound‐guided thrombin injection. The therapeutic armamentarium for the remaining PAs ranges from different interventional procedures to surgical occlusion. In a small case series, we describe our initial experiences with a new, less invasive approach after unsuccessful compression therapy. Ultrasound‐guided injection of 52 ± 33 ml saline beneath the communication tract of the PA yields to rapid occlusion in six consecutive patients. During 4 weeks of follow‐up, the PAs remained occluded in all patients and surgical intervention could be avoided. Cathet Cardiovasc Intervent 2003;58:500–504. © 2003 Wiley‐Liss, Inc.
Intravascular ultrasound analysis of nonstented adjacent segments in diffuse in‐stent restenosis treated with radiation therapy with a rhenium‐188–filled balloon
Authors: Hong Myeong‐Ki , Park Seong‐Wook , Moon Dae‐Hyuk , Oh Seung‐Jun , Lee Cheol Whan , Kim Young‐Hak , Lee Jae‐Whan , Song Jong‐Min , Kang Duk‐Hyun , Song Jae‐Kwan , Kim Jae‐Joong , Park Seung‐Jung
Published: March 2003

The effects of β‐radiation therapy on nonstented adjacent segments in in‐stent restenosis have not been sufficiently evaluated. β‐radiation therapy for in‐stent restenosis was performed with a 188Re‐MAG3–filled balloon. We evaluated the effects of β‐radiation therapy on nonstented adjacent segments in in‐stent restenosis by intravascular ultrasound (IVUS) analysis in 50 patients who received radiation therapy vs. 9 control patients. The changes (Δ = follow‐up − postintervention) of the external elastic membrane (EEM), the lumen, and other IVUS variables were compared between the segments that received radiation therapy and the control segments. The significant differences between the two groups were as follows: Δ EEM area was 0.3 mm2 in the radiation vs. −1.0 mm2 in the control (P = 0.005) and Δ lumen area was 0.2 mm2 vs. −1.3 mm2, respectively (P < 0.001). In conclusion, compared with the changes of vessel shrinkage in the control group, significant vessel enlargement occurred in the nonstented adjacent segments that received radiation therapy. Cathet Cardiovasc Intervent 2003;58:428–433. © 2003 Wiley‐Liss, Inc.
Safety and efficacy of a novel device for treatment of thrombotic and atherosclerotic lesions in native coronary arteries and saphenous vein grafts: Results from the multicenter X‐sizer for treatment of thrombus and atherosclerosis in coronary applications trial (X‐TRACT) study
Authors: Stone Gregg W. , Cox David A. , Low Reginald , Cates Christopher U. , Satler Lowell , Bailey Steven R. , Kuntz Richard E. , Lansky Alexandra J.
Published: March 2003

Intervention in thrombotic lesions and diseased saphenous vein grafts frequently results in thromboembolic complications, including no‐reflow, distal branch occlusion, periprocedural MI, and death. The utility of a novel thromboatherectomy device, the X‐Sizer, was tested in 50 consecutive patients at nine U.S. centers. A total of 61 lesions were treated in 31 vein grafts and 19 native coronary arteries; thrombus was present in 78% of lesions, and TIMI 0–1 flow in 21%. TIMI 3 flow improved from 57% at baseline to 94% postprocedure. No patient developed visible distal thromboemboli, side‐branch occlusion, or reduced antegrade flow. Thirty‐day events included one death (2.0%), Q‐ or non–Q‐wave MI in 4.0%, TVR in 6.0%, and any MACE in 6.0%. We conclude that the use of the X‐Sizer prior to percutaneous intervention is safe in high‐risk vein grafts and thrombotic lesions and results in a low rate of adverse events compared to historical controls. Cathet Cardiovasc Intervent 2003;58:419–427. © 2003 Wiley‐Liss, Inc.
Partial least squares for discrimination
Authors: Barker Matthew , Rayens William
Published: March 2003

Partial least squares (PLS) was not originally designed as a tool for statistical discrimination. In spite of this, applied scientists routinely use PLS for classification and there is substantial empirical evidence to suggest that it performs well in that role. The interesting question is: why can a procedure that is principally designed for overdetermined regression problems locate and emphasize group structure? Using PLS in this manner has heurestic support owing to the relationship between PLS and canonical correlation analysis (CCA) and the relationship, in turn, between CCA and linear discriminant analysis (LDA). This paper replaces the heuristics with a formal statistical explanation. As a consequence, it will become clear that PLS is to be preferred over PCA when discrimination is the goal and dimension reduction is needed. Copyright © 2003 John Wiley & Sons, Ltd.
Resolution of two‐way data from spectroscopic monitoring of reaction or process systems by parallel vector analysis (PVA) and window factor analysis (WFA): inspection of the effect of mass balance, methods and simulations
Authors: Jiang Jian‐Hui , Šašić Slobodan , Yu Ru‐Qin , Ozaki Yukihiro
Published: March 2003

The effect of mass balance on the analysis of two‐way data of reaction or process systems is investigated. It is shown that the rank‐deficient species‐related bilinear model can be converted to a full‐rank reaction‐related bilinear model, and in general situations the chemical rank for a system is the number of reactions plus one. Two slightly modified procedures are thus suggested to extract the spectral subspaces essential for resolution and to ascertain the number of reactions in different time domains. Based on the reaction‐related bilinear model, a procedure of window factor analysis (WFA) is implemented for resolving the extent curves of reactions. A new two‐way resolution approach, parallel vector analysis (PVA), is also developed. The idea of PVA is to construct a set of subspaces comprising only one common (spectral) component and then find a vector that is in parallel with a series of vectors coming from different subspaces. With suitably constructed subspaces the PVA procedure offers a versatile avenue to approach the unique resolution of spectral profiles. A four‐component system which comprises four different processes or reactions is simulated. Results obtained reveal that favorable resolution is achieved for the spectral and concentration profiles by the suggested procedures of WFA and PVA. Copyright © 2003 John Wiley & Sons, Ltd.
DFT Study of the NMR Properties of Xenon in Covalent Compounds and van der Waals Complexes—Implications for the Use of 129Xe as a Molecular Probe
Authors: Bagno Alessandro , Saielli Giacomo
Published: March 2003

The NMR properties (chemical shift and spin–spin coupling constants) of 129Xe in covalent compounds and weakly bound complexes have been investigated by DFT methods including relativistic effects. For covalent species, a good agreement between experimental and calculated results is achieved without scalar relativistic effects, but their inclusion (with a triple‐ζ, double‐polarization basis set) leads to some improvement in the quality of the correlation. The spin–orbit coupling term has a significant effect on the shielding constant, but makes a small contribution to the chemical shift. Coupling constants contain substantial contributions from the Fermi contact and paramagnetic spin–orbit terms; unlike light nuclei the spin–dipole term is also large, whereas the diamagnetic spin–orbit term is negligible. For van der Waals dimers, the dependence of the xenon chemical shift and anisotropy is calculated as a function of the distance. Small (<1 Hz) but non‐negligible through‐space coupling constants between 129Xe and 13C or 1H are predicted. Much larger couplings, of the order of few Hz, are calculated between xenon and 17O in a model silicate residue.
Theoretical Study of the [2+3] Cycloaddition of Nitrones to Nitriles—Influence of Nitrile Substituent, Solvent and Lewis Acid Coordination
Authors: Wagner Gabriele
Published: March 2003

The [2+3] cycloaddition of nitrone PhCHN(Me)O to nitriles RCN (R=Me, Ph, CF3) was studied using quantum chemical calculations at the HF/6‐31G* and B3LYP/6‐31G* level of theory. With MeCN and PhCN, the reaction occurs through a concerted mechanism and leads selectively to Δ4‐1,2,4‐oxadiazolines rather than Δ2‐1,2,5‐oxadiazolines. Electron withdrawing substituents such as CF3 at the nitrile provoke a non‐synchronous bond formation, with the CO bond being established on an earlier stage than the CN bond. Additionally, the reaction becomes thermodynamically and kinetically more favourable. In the reaction of adducts of MeCN with BH3 or BF3 as model Lewis acids, the mechanism was found to change from fully concerted in the case of free MeCN towards a two‐step reaction in the presence of BF3, in which CO bond formation occurs first. The BH3‐mediated reaction occupies an intermediate stage where ring formation occurs in one‐step but non‐simultaneously, similar to the reaction of CF3CN. Interaction of the Lewis acid with the nitrile in the course of the reaction facilitates the cycloaddition by stabilizing transition states, intermediate and product rather than by activating the nitrile. The solvent influences the organic reaction mainly by lowering the energy of the reagents, thus leading to a higher activation barrier in a more polar solvent. In the Lewis acid mediated reaction, in contrast, the intermediate is strongly stabilised by a polar solvent and with that the synchronicity of the reaction changes in favour of a two‐step mechanism.
Palladium‐Catalyzed Cascade Reaction of α,β‐Unsaturated Sulfones with Aryl Iodides
Authors: Mauleón Pablo , Núñez Angel A. , Alonso Inés , Carretero Juan C.
Published: March 2003

Unlike traditionally used acyclic 1,2‐disubstituted alkenes, the reaction of α,β‐unsaturated phenyl sulfones with aryl iodides under Heck reaction conditions (Pd(OAc)2 as catalyst, Ag2CO3 as base in DMF at 120 0C) takes place mainly by a cascade process, involving one unit of the alkene and three units of the aryl iodide, to afford a substituted 9‐phenylsulfonyl‐9,10‐dihydrophenanthrene. The dominant formation of this 3:1 coupling product, instead of the Heck trisubstituted olefin, shows that aromatic CH activation processes can compete with the usually fast syn β‐hydrogen elimination step in the Heck arylation of an acyclic olefin. The structural scope of this palladium‐catalyzed cascade arylation of α,β‐unsaturated sulfones has proved to be wide with regard to substitution at the β‐position (alkyl, aryl, or alkenyl substitution), substitution at the sulfone unit (alkyl or phenyl sulfones), and configuration at the CC bond (trans or cis). Moreover, although less favored than in the case of the arylation of α,β‐unsaturated sulfones, similarly substituted 9,10‐dihydrophenanthrenes have also been obtained in the case of α,β‐unsaturated phosphine oxides and α,β‐unsaturated phosphonate esters. A Pd0–PdII–PdIV mechanistic pathway involving the successive formation of highly electrophilic σ‐alkylpalladium intermediates and palladacycles is proposed for this multicomponent arylation.
Quantitative Comparison of Kinetic Stabilities of Metallomacrocycle‐Based Rotaxanes
Authors: Chang Sung‐Youn , Jang Hye‐Young , Jeong Kyu‐Sung
Published: March 2003

Four mononuclear metallomacrocycles with identical cavities but different transition metals (OsVI, PdII, PtII, and ReI) were prepared. With these metallomacrocycles, the corresponding rotaxanes 2‐Os, 2‐Pd, 2‐Pt, and 2‐Re were self‐assembled by hydrogen‐bonding interactions. The kinetic stabilities of the rotaxanes were determined quantitatively and compared with each other by 1H NMR spectroscopic techniques, including two‐dimensional exchange spectroscopy (2D‐EXSY) experiments. The activation free energies (ΔG≠) for the exchange between the rotaxanes 2‐Os, 2‐Pd and 2‐Pt and their free components were determined to be 15.5, 16.0, and 16.4 kcal mol−1, respectively. These magnitudes imply that the rotaxanes 2‐Os, 2‐Pd and 2‐Pt are kinetically labile at room temperature and exist only as equilibrium mixtures with free components in solution. In contrast, the rotaxane 2‐Re is kinetically stable enough to be isolated in pure form by silica gel chromatography under ordinary laboratory conditions. However, at higher temperatures (>60 °C) 2‐Re was slowly disassembled into its components until the equilibrium was established. The rate constants were measured at three different temperatures, and the Eyring plot yielded the activation enthalpy ΔH≠=35 kcal mol−1 and the activation entropy ΔS≠=27 eu for the disassembly of the rotaxane 2‐Re in Cl2CDCDCl2. These thermodynamic parameters gave the activation free energy ΔG$\rm{^{\ne }_{off}}$=27.1 kcal mol−1 at 25 °C. Consequently, 2‐Re is one example of a novel metallomacrocycle‐based rotaxane that contains a coordination bond with enough strength to allow both for isolation in pure form around room temperature and for self‐assembly at higher temperatures.
The Structure of Lipid A of the Lipopolysaccharide from Burkholderia caryophylli with a 4‐Amino‐4‐deoxy‐L‐arabinopyranose 1‐Phosphate Residue Exclusively in Glycosidic Linkage
Authors: Molinaro Antonio , Lindner Buko , De Castro Cristina , Nolting Birte , Silipo Alba , Lanzetta Rosa , Parrilli Michelangelo , Holst Otto
Published: March 2003

From the lipopolysaccharides (LPSs) of the plant‐pathogenic bacterium Burkholderia caryophylli, the complete structure of lipid A has been characterized. For the first time, a 4‐amino‐4‐deoxy‐L‐arabinopyranose 1‐phosphate residue was proven to be exclusively linked to the reducing end of lipid A from a wild‐type LPS. The LPSs of B. caryophylli were degraded by mild acetate buffer hydrolysis at pH 4.4. The obtained lipid A was analyzed as such, and also after de‐O‐acylation or dephosphorylation. The structure of lipid A was identified mainly by means of matrix‐assisted laser desorption/ionisation mass spectrometry, and by various 1D and 2D 1H and 13C NMR spectroscopic measurements.
Shape‐Controlled Bridged Silsesquioxanes: Hollow Tubes and Spheres
Authors: Moreau Joël J. E. , Vellutini Luc , Wong Chi Man Michel , Bied Catherine
Published: March 2003

A new approach for the morphological control of bridged silsesquioxanes has been achieved by the hydrolysis of silylated organic molecules bearing urea groups. The urea groups are responsible for the auto‐association of the molecules through intermolecular hydrogen‐bonding interactions. The self‐assembly leads to supramolecular architectures that have the ability to direct the organization of hybrid silicas under controlled hydrolysis. The hydrolysis of the chiral diureido derivatives of trans‐(1,2)‐diaminocyclohexane 1 under basic conditions has been examined. The solid‐state NMR spectra (29Si and 13C) showed the hybrid nature of these materials with wholly preserved SiC covalent bonds throughout the silicate network. Hybrid silicas with hollow tubular morphologies were obtained by the hydrolysis of the enantiomerically pure compounds, (R,R)‐1 or (S,S)‐1, whereas the corresponding racemic mixture, rac‐1, led to a hybrid with ball‐like structures. The tubular shape is likely to result from a combination of two phenomena: the auto‐association abilities and a self‐templating structuration of the hybrid materials by the organic crystalline precursor. Electronic microscopy techniques (SEM and TEM) gave evidence for the self‐templating pathway. The formation of the ball‐like structures occurs through a usual nucleation growth phenomenon owing to a higher solubility of the corresponding crystals in the same medium.
Synthesis, Structure, and Properties of Novel Open‐Cage Fullerenes Having Heteroatom(s) on the Rim of the Orifice
Authors: Murata Yasujiro , Murata Michihisa , Komatsu Koichi
Published: March 2003

A thermal liquid‐phase reaction of fullerene C60 with 3‐(2‐pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine afforded aza‐open‐cage fullerene derivative 5 having an eight‐membered‐ring orifice on the fullerene cage. Compound 5 was found to undergo oxidative ring‐enlargement reactions with singlet oxygen under photo‐irradiation to give azadioxo‐open‐cage fullerene derivatives 9 and 10, which have a 12‐membered‐ring orifice, in addition to a small amount of azadioxa‐open‐cage fullerene derivative 11, which has a 10‐membered‐ring orifice. A thermal reaction of 9 with elemental sulfur in the presence of tetrakis(dimethylamino)ethylene resulted in further ring‐enlargement to give azadioxothia‐open‐cage fullerene derivative 15, which has a 13‐membered‐ring orifice. The structures of 5 and 15 were determined by X‐ray crystallography, while those of 9, 10, and 11 were confirmed by the agreement of observed 13C NMR spectra with those obtained by DFT‐GIAO calculations. These reactions were rationalized based on the results of molecular orbital calculations. Following electrochemical measurements, compounds 9 and 10, which have two carbonyl groups on the rim of the orifice, were found to be more readily reduced than C60 itself (the first reduction potential was found to be 0.2 V lower than that of C60), while the first reduction potentials of other open‐cage fullerene derivatives, 5, 11, and 15, were nearly the same as that of C60.