bluuebunny/crossref_metadata_2025_split huggingface dataset:
Engineering analysis of the reactive extrusion of ϵ‐caprolactone: The influence of processing on molecular degradation during reactive extrusion
Authors: Kim Byong Jun , White James L. 
Published: August 2004

AbstractWe have observed that earlier models of the reactive extrusion of ϵ‐caprolactone (CL), which do not include a consideration of mechanical degradation, significantly overpredict the molecular weights of the product. We have performed an engineering analysis of the increase in the molecular weight and the shear‐induced reduction of the molecular weight after the polymerization of CL during reactive extrusion. The variation of the molecular weight has been correlated to the polymerization rate and the mechanical power input into the poly(ϵ‐caprolactone) (PCL) melt. We first compute the increase in the molecular weight of PCL during reactive extrusion as a function of the mean residence time until the conversion is completed. Subsequently, we compute the shear‐induced reduction of the molecular weight after polymerization through the reactive extrusion of CL. The influence of the mechanical load on the PCL melt with increasing shear stress is important for predicting the molecular weight of the final product, particularly after polymerization. Our approach to the prediction of the reduction of the molecular weight is based on the correlation between the specific mechanical energy (i.e., the energy consumed per unit of mass of the material extruded) and the molecular weight. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1007–1017, 2004
Dyeing kinetics of methacrylic acid grafted polyester fabric with astrazonrot violet and rhodamine red basic dyes
Authors: El‐Gendy E. H. 
Published: August 2004

AbstractThe low‐temperature dyeing kinetics of radiation‐grafted poly(ethylene terephthalate) fabric were studied. The effects of the graft yield (GY), dye concentration, and dyeing temperature on the color difference (CD) of methacrylic acid grafted polyester fabric were studied for astrazonrot violet (AV) and rhodamine red (RR) basic dyes. CD increased sharply with an increase in GY and tended to level off at higher degrees of grafting. The best dyeing conditions were achieved for both dyes at pH 11.5. CD of the grafted fabric increased rapidly as the dyeing time increased; this was followed by a relatively slow dyeing rate within a few minutes, which depended on the concentration and temperature of the dye bath. The initial dyeing rates and rate constants for the AV dye were higher than those for the RR dye. The dyeing process followed 0.14‐order kinetics and was independent of the dyeing temperature or the type of dye. The dyeing rates and rate constants increased with an increase in the dyeing temperature. An Arrhenius‐type plot of the natural logarithm of the dyeing rate constant versus the inverse of the absolute temperature yielded apparent activation energies of 4.9 and 13.8 kJ/mol and pre‐exponential rate constants of 9.4 and 100.6 (CD/GY)s−1 for the AV and RR dyes, respectively. The mechanism of the dyeing process for the two dyes was diffusion‐controlled, and their dyeing rates depended on the type of basic dye. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1070–1076, 2004
Optimal therapeutic approaches to femoropopliteal artery intervention
Authors: Das Tony 
Published: August 2004

AbstractSuperficial femoral artery disease presents a complex challenge for therapy. The extent of vascular involvement may vary from focal disease with symptoms of intermittent claudication to long total occlusions manifest as critical limb ischemia. Optimal therapy requires understanding the available options including exercise programs, pharmacologic medical therapy, surgery and interventional endovascular therapy. Rapidly advancing endovascular technology for enabling safe intervention in complex, long occlusive segments of the superficial femoral artery continues to emerge. New devices like the SafeCross wire, Excimer laser, Silverhawk Atherectomy catheter, Cryoplasty catheter and new generations of bare metal and drug‐eluting nitinol stents are shifting the paradigm for therapy from surgical to more endovascular treatment even for the most complex disease presentation. Catheter Cardiovasc Interv 2004;63:21–30. © 2004 Wiley‐Liss, Inc.
Transcatheter closure of fistula between the right pulmonary artery and left atrium using the Amplatzer duct occluder
Authors: Francis Edwin , Sivakumar Kothandam , Kumar Raman Krishna 
Published: August 2004

AbstractA congenital fistula between the right pulmonary artery and the left atrium is a rare condition that results in cyanosis. We report a successful catheter‐based closure of such a fistula in a 12‐year‐old using an Amplatzer duct occluder. The patient also had an atrial septal defect that was closed with an Amplatzer septal occluder. Catheter Cardiovasc Interv 2004;63:83–86. © 2004 Wiley‐Liss, Inc.
Wireless laser‐assisted angioplasty of the superficial femoral artery in patients with critical limb ischemia who have failed conventional percutaneous revascularization
Authors: Boccalandro Fernando , Muench Andreas , Sdringola Stefano , Rosales Oscar R. 
Published: August 2004

AbstractPercutaneous revascularization has become an effective treatment for patients suffering from chronic critical limb ischemia (CLI) due to chronic atherosclerotic obstructions, including total occlusions. Unlike other vascular beds, total chronic occlusions of the femoropopliteal arteries are frequently found in patients with severe claudication or CLI. As a consequence, patients with long chronic total occlusions of the femoropopliteal arteries are generally not considered optimal candidates for percutaneous revascularization and are frequently referred for surgical revascularization. In the present study, we sought to evaluate the feasibility, safety, and outcome of a modified wireless laser ablation technique to recanalize total occlusions in patients with CLI who had failed conventional percutaneous techniques for limb salvage. Procedural success, complications, actuarial freedom of limb loss, and surgical revascularization were evaluated in 25 patients after a mean follow‐up of 13 ± 8 months. Procedural success was achieved in 21 patients (84%). Actuarial freedom from surgical revascularization or limb loss was 72%. There was one vascular perforation. No deaths or distal embolization occurred. Three patients (12%) required limb amputation during follow‐up, whereas four patients (16%) had surgical revascularization in the presence of feasible vascular targets. Limb salvage was achieved in 88% of patients when laser recanalization was combined with surgical revascularization. These results suggest that the use of laser ablation is safe and facilitates angioplasty and stenting in patients with CLI that failed conventional endovascular revascularization. This technique might prevent limb loss in patients with CLI due to femoropopliteal total occlusions, particularly in patients with unsuitable anatomy for surgical revascularization. Catheter Cardiovasc Interv 2004;63:7–12. © 2004 Wiley‐Liss, Inc.
Contribution of early lumen loss after balloon angioplasty for in‐stent restenosis to lumen loss at follow‐up
Authors: Fujii Kenichi , Masutani Motomaru , Kobayashi Yoshio , Tateishi Jun , Kawasaki Daizo , Ohyanagi Mitsumasa , Mintz Gary S. , Leon Martin B. 
Published: August 2004

AbstractThe treatment of in‐stent restenosis using balloon angioplasty alone often produces excellent early results, but is associated with high rate of recurrence. Previous studies have demonstrated significant tissue reintrusion shortly after the treatment of in‐stent restenosis with balloon angioplasty. The study was designed to elucidate the contribution of early lumen loss 6 hr after balloon angioplasty to lumen loss at follow‐up. We prospectively performed quantitative coronary angiography and intravascular ultrasound in 12 patients with in‐stent restenosis before intervention, after the final procedure, 6 hr later (5.6 ± 1.4 hr), and at follow‐up (7.7 ± 2.3 months). Compared with immediately after balloon angioplasty, by 6 hr postintervention, the minimum lumen diameter (MLD) and lumen cross‐sectional area had decreased significantly (2.48 ± 0.44 to 2.01 ± 0.57 mm, P = 0.01, and 7.0 ± 1.2 to 5.5 ± 1.4 mm2, P = 0.004, respectively). Furthermore, the MLD decreased further between 6 hr postintervention and long‐term follow‐up (2.01 ± 0.57 to 1.55 ± 0.64 mm; P = 0.001). Patients who showed recurrence of restenosis at follow‐up had greater early lumen loss than patients without recurrence of restenosis (0.71 ± 0.31 vs. 0.23 ± 0.13 mm; P = 0.006). Diffuse lesions had greater early lumen loss compared to focal lesions (0.75 ± 0.35 vs. 0.28 ± 0.13 mm; P = 0.008). Early lumen loss is common after the treatment of in‐stent restenosis by balloon angioplasty. Within the first 6 hr postintervention, 32% ± 29% of acute lumen gain is lost, and early lumen loss contributed to 42% ± 18% of total lumen loss at follow‐up. Catheter Cardiovasc Interv 2004;63:52–56. © 2004 Wiley‐Liss, Inc.
Balloon angioplasty plus cilostazol administration versus primary stenting of small coronary artery disease: Final results of COMPASS
Authors: Tsuchikane Etsuo , Takeda Yoshihiro , Nasu Kenya , Awata Nobuhisa , Kobayashi Tohru 
Published: August 2004

AbstractEfficacy of primary stenting in small coronary artery disease is still controversial. Cilostazol has been reported to control restenosis after balloon angioplasty (BA). The aim was to compare primary stenting with BA plus cilostazol administration in small coronary artery disease. Of 106 lesions located in small coronary artery (reference < 3.0 mm), 50 lesions were randomly assigned to the stenting and 56 lesions to the BA‐cilostazol group. Multilink stent was implanted in the stenting group. In the BA‐cilostazol group, cilostazol (200 mg/day) without aspirin was administered for 6 months after BA. Ticlopidine was given for 1 month when bailout stent was implanted. Serial quantitative angiography was performed at the procedure and 6 months. The primary endpoint was 6‐month angiographic restenosis. Clinical event rates at 1 year were also assessed. Baseline characteristics were similar. All procedures were successful. Bailout stenting was performed in three lesions in the BA‐cilostazol group. No side effects of cilostazol were observed. Postprocedural lumen diameter was significantly larger (2.69 vs. 2.03 mm; P < 0.0001) in the stenting group. However, the follow‐up lumen diameter was not different (1.76 vs. 1.85 mm, stenting vs. BA‐cilostazol). Although the difference was not statistically significant, restenosis rate was lower in the BA‐cilostazol group (13.2% vs. 24.5%; P = 0.11). Subacute thrombosis occurred in one patient and target revascularization rate was higher in the stenting group (22.0% vs. 10.7%; P = 0.10). BA plus cilostazol administration seems to be a favorable strategy for small coronary artery disease. Catheter Cardiovasc Interv 2004;63:44–51. © 2004 Wiley‐Liss, Inc.
Percutaneous stent‐mounted valve for treatment of aortic or pulmonary valve disease
Authors: Webb John G. , Munt Bradley , Makkar Raj R. , Naqvi Tasneem Z. , Dang Ninh 
Published: August 2004

AbstractThe objective of this study was to develop a prosthetic cardiac valve designed for percutaneous transcatheter implantation. Percutaneous catheter‐based therapies play a limited role in the management of cardiac valve disease. Surgical implantation of prosthetic valves usually requires thoracotomy and cardiopulmonary bypass. The stent‐valve is constructed of a rolled sheet of heat‐treated nitinol. Although malleable when cooled, once released from a restraining sheath at body temperature the stent unrolls, becomes rigid, and assumes its predetermined cylindrical conformation. A ratcheting lock‐out mechanism prevents recoil and external protrusions facilitate anchoring. Valve leaflets are constructed of bovine pericardium. The feasibility of catheter implantation, prosthetic valve function, and survival were investigated in an animal model. In vitro and pulse duplicator testing documented valve durability. Endovascular delivery of the prototype stent‐valve to the aortic or pulmonary position was feasible. Accurate positioning was required to ensure exclusion of the native valve leaflets and, in the case of the aortic valve, to avoid compromise of the coronary ostia or mitral apparatus. Oversizing of the stent in relation to the valve annulus was desirable to facilitate anchoring and prevent paravalvular insufficiency. Stent‐valve implantation proved feasible and compatible with survival in an animal model. Transcatheter implantation of prosthetic valves is possible. Further evolution of this technology will involve lower‐profile devices with design features that facilitate vascular delivery, visualization, positioning, deployment, and valvular function. Catheter Cardiovasc Interv 2004;63:89–93. © 2004 Wiley‐Liss, Inc.
Stent implantation for coarctation of aorta caused by a Rashkind patent ductus arteriosus umbrella
Authors: Beck Avi , Birk Einat , Blieden Leonard C. , Bruckheimer Elchanan 
Published: August 2004

AbstractThis case demonstrates a novel use of stent implantation for relief of coarctation of the aorta caused by protrusion of a Rashkind patent ductus arteriosus umbrella. Follow‐up 3 years after stent implantation shows complete relief of obstruction. Catheter Cardiovasc Interv 2004;63:80–82. © 2004 Wiley‐Liss, Inc.
Fine Structures of Zeolite‐Linde‐L (LTL): Surface Structures, Growth Unit and Defects
Authors: Ohsuna Tetsu , Slater Ben , Gao Feifei , Yu Jihong , Sakamoto Yasahiro , Zhu Gaugshan , Terasaki Osamu , Vaughan David E. W. , Qiu Shilun , Catlow C. Richard A. 
Published: August 2004

AbstractHigh‐resolution electron microscopy (HREM) has been used to image the surface structure of nano‐ and micrometer‐sized synthetic crystals of zeolite‐Linde‐L (LTL). Columnar holes and rotational, nano‐sized, wheel‐like defects were observed within the crystals, where the hole has a minimum size equal to that of the rotational defect. Predictions of surface structure from atomistic computer simulation concur with the observations from HREM and provide insight into the crystal growth mechanism of perfect and defective LTL. Analysis of the energetics of the formation of rotational defect structures reveals that the driving force for defect creation is thermodynamic and furthermore, the rotational defects could be created in high concentrations. Formation of a columnar hole is found to be slightly energetically unfavourable and therefore we speculate that the incidence of both rotational and nano‐sized vacancy defects is strongly dependent on kinetic factors and reaction conditions. The morphology of nano‐ and microcrystalline LTL is contradistinct and we use insights from simulation to propose an explanation of the disparity in crystal shape.
Effective use of preparative chiral HPLC in a preclinical drug synthesis
Authors: Nelson Todd D. , Welch Christopher J. , Rosen Jonathan D. , Smitrovich Jacqueline H. , Huffman Mark A. , McNamara James M. , Mathre David J. 
Published: August 2004

AbstractAccess to a key 3‐aryl‐δ‐lactone intermediate in enantiopure form using preparative chiral chromatography allowed expedited preparation of an important drug discovery target. A preclinical drug discovery strategy that combines rapid route discovery with effective use of preparative chiral chromatography can result in significant savings of both time and labor. Chirality 16:609–613, 2004. © 2004 Wiley‐Liss, Inc.
First optically active selenurane oxide: Resolution of C2‐symmetric 3,3,3′,3′‐tetramethyl‐1,1′‐spirobi [3h,2,1]‐benzoxaselenole oxide
Authors: Drabowicz Józef , Luczak Jerzy , Mikolajczyk Marian , Yamamoto Yohsuke , Matsukawa Shiro , Akiba Kin‐Ya 
Published: August 2004

AbstractThe enantiomers of the first optically active selenurane oxide ever reported, C2‐symmetric 3,3,3′,3′‐tetramethyl‐1,1′‐spirobi[3h,2,1]‐benzoxaselenole oxide, were isolated via enantioselective liquid chromatography of the racemate or by spontaneous resolution that occurs during the slow evaporation of its acetonitrile solution or the slow crystallization from the same solvent. Chirality 16:598–601, 2004. © 2004 Wiley‐Liss, Inc.
Central nervous system metastases in patients with high‐risk breast carcinoma after multimodality treatment
Authors: Gonzalez‐Angulo Ana M. , Cristofanilli Massimo , Strom Eric A. , Buzdar Aman U. , Kau Shu‐Wan , Broglio Kristine R. , Smith Terry L. , Hortobagyi Gabriel N. 
Published: August 2004

AbstractBACKGROUNDThe current study was performed to determine the incidence of central nervous system (CNS) metastases and to examine associated disease characteristics in a group of patients with locally advanced breast carcinoma (LABC) or inflammatory breast carcinoma (IBC) treated at The University of Texas M. D. Anderson Cancer Center (Houston, TX).METHODSSeven hundred sixty‐eight patients treated with multimodality therapy between 1982 and 2000 in any of 6 neoadjuvant trials were eligible for the current study. Five hundred ninety‐two patients (77%) had LABC, and 176 (23%) had IBC. CNS disease was defined as the presence of brain metastases or leptomeningeal disease. Time to detection of CNS disease and overall survival were estimated using the Kaplan–Meier product‐limit method, and differences were evaluated using log‐rank tests.RESULTSThe median patient age was 48 years. Most tumors were classified as T4 lesions (58%) and exhibited lymph node involvement (78%). Fifty‐one percent of all tumors had positive hormone receptor status. At a median follow‐up duration of 9.5 years, 61 patients (8%) had developed CNS metastases, with the CNS representing the first site of recurrence for 38 of these 61 (63%). Characteristics associated with the development of CNS metastases over time included negative hormone receptor status (P = 0.03), Grade 3 disease (P = 0.01), and larger tumor size (P = 0.02). The median time to detection of CNS metastases was 2.3 years. Ten patients (16%) remained alive after treatment for CNS metastases. The median survival from the time of diagnosis of CNS metastases was 8 months.CONCLUSIONSCNS metastases from breast carcinoma were relatively uncommon and were strongly associated with more aggressive clinical presentation. Survival from the time of diagnosis of such metastases generally was short. Cancer 2004. © 2004 American Cancer Society.
Fluorescent CXCL12AF647 as a novel probe for nonradioactive CXCL12/CXCR4 cellular interaction studies
Authors: Hatse Sigrid , Princen Katrien , Liekens Sandra , Vermeire Kurt , De Clercq Erik , Schols Dominique 
Published: August 2004

AbstractBackgroundChemokines drive the migration of leukocytes via interaction with specific G protein–coupled 7‐transmembrane receptors. The chemokine ligand/receptor pair stromal cell–derived factor‐1 (SDF‐1, CXCL12)/CXCR4 is gaining increasing interest because of its involvement in the metastasis of several types of cancer and in certain inflammatory autoimmune disorders such as rheumatoid arthritis. In addition, CXCR4 serves as an important coreceptor for cellular entry of T‐tropic strains of human immunodeficiency virus (HIV). Therefore, potent and specific CXCR4 antagonists may have therapeutic potential as anti‐HIV, anti‐cancer, and anti‐inflammatory drugs.Methods and ResultsChemokine receptor antagonists can be identified by their ability to inhibit ligand binding to the receptor protein. Until now, chemokine binding assays were mostly performed with radiolabeled chemokine ligands such as [125I]CXCL12. To overcome the practical problems associated with such radioactive chemokine binding assays, we have developed a flow cytometric technique using a new, commercially available Alexa Fluor 647 conjugate of CXCL12 (CXCL12AF647). Calcium flux, chemotaxis, and p44/42 mitogen‐activated protein kinase phosphorylation assays showed that the agonistic activity of the fluorescent CXCL12 was unchanged as compared with that of unlabeled CXCL12. Human T‐lymphoid (CXCR4+) SupT1 cells and CXCR4‐transfected, but not CCR5‐ or CXCR3‐transfected, human astroglioma U87.CD4 cells specifically bound CXCL12AF647 in a concentration‐dependent manner. Unlabeled CXCL12 and the well‐known CXCR4 inhibitors, AMD3100 and T22, blocked the binding of CXCL12AF647 to SupT1 cells with 50% inhibitory concentrations of 92, 13, and 8 ng/ml, respectively. We have also used this method to evaluate CXCL12 binding and CXCR4 expression level in different subsets of human peripheral blood mononuclear cells.ConclusionCXCL12AF647 is a valuable, more convenient alternative for [125I]CXCL12 in ligand/receptor interaction studies. © 2004 Wiley‐Liss, Inc.
Cholesterol sensitivity of detergent resistance: A rapid flow cytometric test for detecting constitutive or induced raft association of membrane proteins
Authors: Gombos Imre , Bacsó Zsolt , Detre Cynthia , Nagy Henrietta , Goda Katalin , Andrásfalvy Márton , Szabó Gábor , Matkó János 
Published: August 2004

AbstractBackgroundLipid rafts are cholesterol‐ and glycosphingolipid‐rich microdomains in the cellular plasma membranes that play critical roles in compartmentalization (concentration, coupling, and isolation) of receptors and signal molecules. Therefore, detecting constitutive or induced raft associations of such proteins is of central interest in cell biology. This has mostly been done with time‐ and cell‐consuming immunobiochemical techniques affected by several sources of artifacts. A flow cytometric analysis of immunocytochemical staining under differential circumstances of detergent treatment offers a new alternative to this method.MethodsMembrane microdomains are resistant to nonionic detergents due to extensive, strong interactions between their molecular constituents. We used this feature to develop a rapid flow cytometric assay of differential detergent resistance based on immunocytochemical labeling of extracellular domain epitopes in membrane proteins. Data evaluation is based on comparative detection of their detergent solubility without and with cholesterol depletion of cell membranes, resolved by moderate concentrations of nonionic detergents.ResultsNonionic detergents Triton X‐100 and Nonidet‐40 (0.05–0.1%) in cold or Brij‐98 (0.1–0.5%) at 37°C efficiently resolved detergent solubility or resistance of many lymphocyte cell surface proteins. Kinetic data revealed that a short (5–10 min) detergent treatment is sufficient for this assay. Comparison of detergent solubility in untreated and cholesterol‐depleted cells differentiated membrane proteins associated with or excluded from raft microdomains, respectively. Confocal microscopy showed that this mild detergent treatment leaves the cytoskeleton of the cells intact, with a detectable expression of raft marker detergent‐resistant proteins attached to it. An induced association with rafts of immunoglobulin E receptors upon antigen cross‐linking was also easily detectable in rat mast cells by this approach.ConclusionsA protocol is proposed for a rapid (5–10 min) test of detergent resistance of membrane proteins in cells. The approach requires only a small amount of cells (104/sample) and offers a good resolution of detergent solubility or resistance of membrane proteins, also in terms of the underlying mechanisms, with an advantage of applicability for all conventional bench‐top flow cytometers. © 2004 Wiley‐Liss, Inc.