bluuebunny/crossref_metadata_2025 huggingface dataset:
Recognition of double‐stranded RNA by proteins and small molecules
Authors: Carlson Coby B. , Stephens Olen M. , Beal Peter A.
Published: August 2003

Molecular recognition of double‐stranded RNA (dsRNA) is a key event for numerous biological pathways including the trafficking, editing, and maturation of cellular RNA, the interferon antiviral response, and RNA interference. Over the past several years, our laboratory has studied proteins and small molecules that bind dsRNA with the goal of understanding and controlling the binding selectivity. In this review, we discuss members of the dsRBM class of proteins that bind dsRNA. The dsRBM is a ∼70 amino acid sequence motif found in a variety of dsRNA‐binding proteins. Recent results have led to a new appreciation of the ability of these proteins to bind selectivity to certain sites on dsRNA. This property is discussed in light of the RNA selectivity observed in the function of two proteins that contain dsRBMs, the RNA‐dependent protein kinase (PKR) and an adenosine deaminase that acts on dsRNA (ADAR2). In addition, we introduce peptide–acridine conjugates (PACs), small molecules designed to control dsRBM–RNA interactions. These intercalating molecules bear variable peptide appendages at opposite edges of an acridine heterocycle. This design imparts the potential to exploit differences in groove characteristics and/or base‐pair dynamics at binding sites to achieve selective binding. © 2003 Wiley Periodicals, Inc. Biopolymers, 2003
Molecular recognition of aminoglycoside antibiotics by ribosomal RNA and resistance enzymes: An analysis of x‐ray crystal structures
Authors: Vicens Quentin , Westhof Eric
Published: August 2003

The potential of RNA molecules to be used as therapeutic targets by small inhibitors is now well established. In this fascinating wide‐open field, aminoglycoside antibiotics constitute the most studied family of RNA binding drugs. Within the last three years, several x‐ray crystal structures were solved for aminoglycosides complexed to one of their main natural targets in the bacterial cell, the decoding aminoacyl–tRNA site (A site). Other crystallographic structures have revealed the binding modes of aminoglycosides to the three existing types of resistance‐associated enzymes. The present review summarizes the various aspects of the molecular recognition of aminoglycosides by these natural RNA or protein receptors. The analysis and the comparisons of the detailed interactions offer insights that are helpful in designing new generations of antibiotics. © 2003 Wiley Periodicals, Inc. Biopolymers, 2003
Fluorescence‐based methods for evaluating the RNA affinity and specificity of HIV‐1 Rev–RRE inhibitors
Authors: Luedtke Nathan W. , Tor Yitzhak
Published: August 2003

RNA plays a pivotal role in the replication of all organisms, including viral and bacterial pathogens. The development of small molecules that selectively interfere with undesired RNA activity is a promising new direction for drug design. Currently, there are no anti‐HIV treatments that target nucleic acids. This article presents the HIV‐1 Rev response element (RRE) as an important focus for the development of antiviral agents that target RNA. The Rev binding site on the RRE is highly conserved, even between different groups of HIV‐1 isolates. Compounds that inhibit HIV replication by binding to the RRE and displacing Rev are therefore expected to retain activity across groups of genetically diverse HIV infections. Systematic evaluations of both the RRE affinity and specificity of numerous small molecule inhibitors are essential for deciphering the parameters that govern effective RRE recognition. This article discusses fluorescence‐based techniques that are useful for probing a small molecule's RRE affinity and its ability to inhibit Rev–RRE binding. Rev displacement experiments can be conducted by observing the fluorescence anisotropy of a fluorescein‐labeled Rev peptide, or by quantifying its displacement from a solid‐phase immobilized RRE. Experiments conducted in the presence of competing nucleic acids are useful for evaluating the RRE specificity of Rev‐RRE inhibitors. The discovery and characterization of new RRE ligands are described. Eilatin is a polycyclic aromatic heterocycle that has at least one binding site on the RRE (apparent Kd ≈ 0.13 μM), but it does not displace Rev upon binding the RRE (IC50 > 3 μM). In contrast, ethidium bromide and two eilatin‐containing metal complexes show better consistency between their RRE affinity and their ability to displace a fluorescent Rev peptide from the RRE. These results highlight the importance of conducting orthogonal binding assays that establish both the RNA affinity of a small molecule and its ability to inhibit the function of the RNA target. Some Rev–RRE inhibitors, including ethidium bromide, Λ‐[Ru(bpy)2eilatin]2+, and Δ‐[Ru(bpy)2eilatin]2+ also inhibit HIV‐1 gene expression in cell cultures (IC50 = 0.2–3 μM). These (and similar) results should facilitate the future discovery and implementation of anti‐HIV drugs that are targeted to viral RNA sites. In addition, a deeper general understanding of RNA–small molecule recognition will assist in the effective targeting of other therapeutically important RNA sites. © 2003 Wiley Periodicals, Inc. Biopolymers, 2003
Sequence and structure space of RNA‐binding peptides
Authors: Das Chandreyee , Frankel Alan D.
Published: August 2003

Studies of RNA‐binding peptides, and recent combinatorial library experiments in particular, have demonstrated that diverse peptide sequences and structures can be used to recognize specific RNA sites. The identification of large numbers of sequences capable of binding to a particular site has provided extensive phylogenetic information used to deduce basic principles of recognition. The high frequency at which RNA‐binding peptides are found in large sequence libraries suggests plausible routes to evolve sequence‐specific binders, facilitating the design of new binding molecules and perhaps reflecting characteristics of natural evolution. © 2003 Wiley Periodicals, Inc. Biopolymers, 2003
Differences between endocrine surgeons and endocrinologists in the management of non-toxic multinodular goitre
Authors: Bhagat M C , Dhaliwal S S , Bonnema S J , Hegedüs L , Walsh J P
Published: August 2003

Background

It is not known whether the management of multinodular goitre differs between endocrinologists and endocrine surgeons.

Methods

A questionnaire containing a hypothetical case (a 42-year-old euthyroid woman with a 50–80-g multinodular goitre) and 11 variations on the case was sent to endocrinologists and endocrine surgeons in Australia.

Results

The response rate was 55 per cent, including 45 endocrine surgeons and 127 endocrinologists. For the index case, serum thyroid-stimulating hormone (TSH), fine-needle aspiration biopsy and ultrasonography were widely used by both groups. Thyroid antibodies and scintigraphy were ordered by a greater proportion of endocrinologists than surgeons, and computed tomography more frequently by surgeons than endocrinologists. Treatment recommendations differed significantly between specialties for the index case (endocrinologists: no treatment 65 per cent, thyroxine 22 per cent, surgery 10 per cent, radioiodine 3 per cent; surgeons: no treatment 67 per cent, thyroxine 2 per cent, surgery 31 per cent; P < 0·001) and for seven of the variations. In particular, for a patient with suppressed TSH, most endocrinologists (60 per cent) recommended radioiodine treatment, whereas there was no consensus among surgeons (surgery 40 per cent, no treatment 36 per cent, radioiodine 21 per cent). For a patient with a partly intrathoracic goitre, most surgeons (88 per cent) recommended surgery, whereas there was no consensus among endocrinologists (surgery 45 per cent, no treatment 34 per cent, thyroxine treatment 13 per cent, radioiodine 8 per cent).

Conclusion

There are clinically significant differences between endocrine surgeons and endocrinologists in the management of multinodular goitre.
Early measurement of procalcitonin does not predict severity in patients with acute pancreatitis
Authors: Frasquet J , Sáez J , Trigo C , Martínez J , Such J , Pérez-Mateo M
Published: August 2003

Measurement does not predict severity
Laparoscopic compared with conventional treatment of acute adhesive small bowel obstruction
Authors: Wullstein C , Gross E
Published: August 2003

Background

Although laparoscopy may be associated with fewer intra-abdominal adhesions and quicker recovery of bowel function, it remains unclear whether patients with acute small bowel obstruction (SBO) might benefit from laparoscopic techniques.

Method

The results of patients with acute SBO treated laparoscopically (LAP; n = 52) and conventionally (CONV; n = 52) were compared in a retrospective matched-pair analysis. Conversions were included in the laparoscopic group.

Results

Complete laparoscopic treatment was performed in 25 patients (48·1 per cent). Major intraoperative complications occurred in 15 patients in the LAP group and eight in the CONV group (P = 0·156). Intraoperative perforations were more frequent in patients who had undergone more than one previous laparotomy (P = 0·066). Postoperative complications occurred in ten patients (19·2 per cent) in the LAP group and in 21 patients (40·4 per cent) who had conventional surgery (P = 0·032). Bowel movements started 3·5 days after operation in the LAP group and 4·4 days after conventional operation (P = 0·001). The length of hospital stay was 11·3 and 18·1 days respectively (P < 0·001).

Conclusion

Laparoscopic treatment of acute SBO was feasible in about half of these patients. Postoperative recovery was improved after laparoscopic procedures but the risk of intraoperative complications increased. A laparoscopic approach seems justified in a subset of patients.
Cold provocation testing and hand–arm vibration syndrome—an audit of the results of the Department of Trade and Industry scheme for the evaluation of miners
Authors:   Members of the Medical Reference Panel of the Department of Trade and Industry (UK) HAVS Compensation Scheme, Proud G , Burke F , Lawson I J , McGeoch K L , Miles J N V
Published: August 2003

Background

Hand–arm vibration syndrome (HAVS) is a major industrial disease that causes considerable morbidity among workers exposed to vibration. Compensation is paid to those affected in civil claims against employers and (in the UK) in claims made under Social Security legislation rules for Prescribed Disease A11. Diagnostic tests have been proposed but most are not objective. The cold provocation test (CPT), which is objective, is often included in the evaluation of HAVS.

Methods

A continuous audit was made of the findings recorded at the 18 HAVS test centres in the UK established to evaluate miners. The audit, and its outcome, were monitored by the Medical Reference Panel who advise the Department of Trade and Industry. This audit report constitutes the second analysis of the findings relating to the CPT.

Results

The CPT, with measurement of digital rewarming times, is of no value in assessing vibration-induced damage to the hands.

Conclusion

In its present format, the CPT should not be used for evaluating the vascular component of HAVS.
Randomized clinical trial of preoperative intranasal mupirocin to reduce surgical-site infection after digestive surgery
Authors: Suzuki Y , Kamigaki T , Fujino Y , Tominaga M , Ku Y , Kuroda Y
Published: August 2003

Background

Compromised patients subjected to major digestive surgery frequently develop infective complications caused by methicillin-resistant Staphylococcus aureus (MRSA), which may have dangerous consequences. This was a prospective randomized study to determine whether intranasal mupirocin could reduce postoperative infective complications in patients having digestive surgery.

Methods

A total of 395 patients who underwent abdominal digestive surgery were assigned randomly into two groups: a treated group (193 patients) and controls (202). Patients in the treated group were given 30 mg mupirocin calcium hydrate ointment topically to each nostril three times a day on each of the 3 days before operation. The untreated group received no mupirocin treatment.

Results

Most infections were due to Gram-negative bacteria in both groups. There were 21 Gram-positive infections detected at the surgical site, ten in the treated group and 11 in control patients. The incidence of pneumonia was significantly different between the groups (none in the treated group and five in control patients; P = 0·028). Four of five patients with pneumonia had a sputum culture containing MRSA.

Conclusion

Intranasal mupirocin treatment had no significant impact on surgical-site infection after digestive surgery.
Irish child sexual abuse victims attending a specialist centre
Authors: O'Riordan Beth , Carr Alan , Turner Rhonda
Published: August 2003

We profiled a cohort of CSA cases referred for assessment to a specialist child sexual abuse (CSA) centre in a national paediatric hospital in Ireland. Historical and clinical data were drawn from records of 171 cases. The majority of cases were referred by social workers following purposeful disclosure of CSA. Three quarters of the cases were female with a mean age of 9 years. They were from a wide spectrum of socioeconomic groups and many had suffered a range of family adversities. In most cases, the abuse involved masturbation of the child by the abuser. Almost all of the perpetrators were male with a mean age of 28 years and in 60% of cases extrafamilial abuse had occurred. In 23% of cases, the perpetrator had a history of previous sexual offending. Anxiety was the most common emotional problem before disclosure and after disclosure the most common emotional problem was guilt. Before disclosure school refusal was the most common behavioural problem and after disclosure fighting was the most prevalent behavioural difficulty. The most common factors supporting the credibility of CSA allegations were labile mood, the child's ability to differentiate fact from fantasy and a detailed disclosure of contextual details. More adolescents showed deterioration in schoolwork after disclosure and for more pre school children clinginess following disclosure was a significant emotional problem. More primary school aged children were abused by perpetrators who had abused a number of children. For children abused by such perpetrators, vaginal intercourse was less common. Vaginal intercourse was more common in 6–11‐year‐old victims and those who were abused on a daily basis. The threat that disclosure posed to the integrity of the family structure was more often a factor hindering disclosure in victims abused by father figures and abused very frequently. Copyright © 2003 John Wiley & Sons, Ltd.
Working in partnership: the development of a home visiting service for vulnerable families
Authors: Barlow Jane , Stewart‐Brown Sarah , Callaghan Helen , Tucker Joanna , Brocklehurst Neil , Davis Hilton , Burns Claire
Published: August 2003

The primary prevention of child abuse is both a clinical and political priority. Home visiting programmes consisting of structured visits by a professional over an extended period of time during the perinatal period have been identified in a number of studies as being a potentially effective means of achieving this. The use of professionally delivered home visiting programmes in the UK to date, however, has been limited. This paper describes the development of an innovative, primary care‐based home visiting service, which is aimed at the primary prevention of maltreatment, abuse and neglect and the promotion of positive parenting and secure attachment. The paper provides a description of the rationale and policy context for the new service and an account of its development, with particular emphasis on the aim of working ‘in partnership’ with families. Copyright © 2003 John Wiley & Sons, Ltd.
The Triple P‐Positive Parenting Programme: a universal population‐level approach to the prevention of child abuse
Authors: Sanders Matthew R. , Cann Warren , Markie‐Dadds Carol
Published: August 2003

The Triple P‐Positive Parenting Programme is described as an example of an evidence‐based universal parenting initiative that provides a tiered continuum of interventions of increasing strength but narrowing reach in an effort to make parenting programmes more accessible to parents. Interventions within the system range from the use of the media and brief messages to intensive family interventions for parents where parenting problems are complicated by multiple additional sources of family adversity. Several issues concerning the role of training and organizational factors that influence the successful uptake and implementation of the programme are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Alternative therapeutic strategies for patients with severe end‐stage coronary artery disease not amenable to conventional revascularization
Authors: Almeda Francis Q. , Parrillo Joseph E. , Klein Lloyd W.
Published: August 2003

Although there have been remarkable advances in medical therapy, percutaneous coronary interventions, and coronary artery bypass graft surgery, complete revascularization remains a challenge given the more complex coronary artery disease prevalent in contemporary practice. The lack of donors for cardiac transplantation will fuel the search for effective alternative strategies for dealing with patients with severe ischemic heart disease not amenable to conventional revascularization techniques. Percutaneous laser revascularization clearly diminishes anginal symptoms; however, the blinded trials have provided conflicting results, with one study showing a definite decrease in angina and another suggesting that the placebo effect may play a major role in this modality. Similarly, surgical transmyocardial laser revascularization is limited by the lack of consistent improvement in objective measurements of ischemia and the potential confounding mechanisms of denervation and the placebo effect, and thus should be reserved for only the most highly selected patients. Although enhanced external counterpulsation is associated with an improvement in anginal symptoms and exercise tolerance, this modality is limited by its availability, tolerability, and rigid exclusion criteria. Of the alternative strategies available, therapeutic angiogenesis holds the most promise. However, the long‐term results of ongoing randomized clinical trials require further scrutiny. Novel methods for vascular reconstruction are evolving techniques, but should be viewed currently as mainly experimental methods. The common goals of these new treatment options would be to reduce symptoms, decrease morbidity, and potentially improve mortality by reducing ischemia through favorably impacting myocardial oxygen supply and demand. The optimal management of patients with severe end‐stage coronary artery disease not amenable to conventional revascularization techniques will continue to remain a challenge for the clinician and will be the main focus of basic cardiovascular research and clinical trials in the new millennium. Catheter Cardiovasc Interv 2003;60:57–66. © 2003 Wiley‐Liss, Inc.
Reproducibility of coronary lumen, plaque, and vessel wall reconstruction and of endothelial shear stress measurements in vivo in humans
Authors: Coskun Ahmet U. , Yeghiazarians Yerem , Kinlay Scott , Clark Maureen E. , Ilegbusi Olusegun J. , Wahle Andreas , Sonka Milan , Popma Jeffrey J. , Kuntz Richard E. , Feldman Charles L. , Stone Peter H.
Published: August 2003

The purpose of this study was to assess the reproducibility of an in vivo methodology to reconstruct the lumen, plaque, and external elastic membrane (EEM) of coronary arteries and estimate endothelial shear stress (ESS). Ten coronary arteries without significant stenoses (five native and five stented arteries) were investigated. The 3D lumen and EEM boundaries of each coronary artery were determined by fusing end‐diastolic intravascular ultrasound images with biplane coronary angiograms. Coronary flow was measured. Computational fluid dynamics was used to calculate local ESS. Complete data acquisition was then repeated. Analysis was performed on each data set in a blinded manner. The intertest correlation coefficients for all arteries for the two measurements of lumen radius, EEM radius, plaque thickness, and ESS were r = 0.96, 0.96, 0.94, 0.91, respectively (all P values < 0.0001). The 3D anatomy and ESS of human coronary arteries can be reproducibly estimated in vivo. This methodology provides a tool to examine the effect of ESS on atherogenesis, remodeling, and restenosis; the contribution of arterial remodeling and plaque growth to changes in the lumen; and the impact of new therapies. Catheter Cardiovasc Interv 2003;60:67–78. © 2003 Wiley–Liss, Inc.
Gold coating and restenosis after primary stenting of ostial renal artery stenosis
Authors: Zeller Thomas , Müller Christian , Frank Ulrich , Bürgelin Karlheinz , Sinn Lutz , Horn Barbara , Roskamm Helmut
Published: August 2003

Predictors of restenosis after stent angioplasty of ostial renal artery stenosis (RAS) and long‐term technical success, particularly the influence of gold coating, are unknown. During a 4‐year period (1996–2000), we treated 156 consecutive patients with 219 ostial RAS of ≥ 70% diameter stenosis. Gold‐coated stents were used in 29% of RAS (n = 64); the vessel diameter ranged from 3 to 9 mm. The restenosis rate was 11.4% at 12 months, 12.2% for gold‐coated stents and 11.1% for noncoated stents. Restenosis rates were 16% for ≤ 4 mm, 17% for 5 mm, 10% for 6 mm, and 0% for ≥ 7 mm (P ≤ 0.05). In a backward stepwise logistic regression analysis including gold coating, vessel diameter, gender, diabetes, smoking status, as well as lesion diameter stenosis before and after stenting, vessel diameter was found the only independent predictor of restenosis (odds ratio = 0.57; 95% CI = 0.35–0.93; P = 0.02, for an increase in vessel diameter of 1 mm). Gold coating was not a significant predictor (odds ratio = 1.09; 95% CI = 0.39–3.03; P = 0.87). Seven major (4.5%) complications occurred. There were no procedural fatalities. The restenosis rate after stent angioplasty of ostial RAS is influenced by the vessel diameter but not by gold coating. Catheter Cardiovasc Interv 2003;60:1–6. © 2003 Wiley–Liss, Inc.
Feasibility and safety of immediate perioperative implantation of intravascular stents in cavopulmonary pathways
Authors: Walayat Muhammad , McArthur Kenneth , Lilley Stuart , Wilson Neil
Published: August 2003

Fontan‐type procedures are widely used for palliation of patients with many forms of a functional univentricular heart. An ideal Fontan circuit should be free of any distortion or stenosis. The use of stents for the treatment of stenotic and hypoplastic vessels is well established in pediatric cardiac practice. We report the successful use of endovascular stents during the immediate postoperative period in patients undergoing cavopulmonary anastomoses. Catheter Cardiovasc Interv 2003;60:94–98. © 2003 Wiley‐Liss, Inc.
Superior vena cava syndrome secondary to saphenous venous graft aneurysm with right atrial fistula
Authors: Fares Wassim , Sharifi Mohsen , Steele Robert , Sarhill Nabeel , Sopko Joseph , Ramana C.V. , Koch J. Michael
Published: August 2003

Mega‐aneurysms of saphenous vein grafts (SVGs) to coronary arteries are rare complications of bypass surgery. We report the development of superior vena cava syndrome secondary to an SVG mega‐aneurysm with concomitant fistulous communication to the right atrium. Successful treatment was achieved by coil embolization and chronic anticoagulation. Catheter Cardiovasc Interv 2003;60:45–47. © 2003 Wiley–Liss, Inc.
Recanalization of a discrete atretic right pulmonary artery segment with a new radiofrequency system
Authors: Pedra Carlos A.C. , Filho Ronaldo Mont'Alverne , Arrieta Raul S. , Tellez Ricardo , Fontes Valmir F.
Published: August 2003

We describe a case in which a discrete atretic segment of the right pulmonary artery (due to a Blalock‐Taussig shunt) was reconstructed using a new radiofrequency system, balloon dilation, and stent implantation in an 18‐month‐old patient. The shunt was coil‐occluded. The technique and applications of this novel approach are discussed. Catheter Cardiovasc Interv 2003;60:82–87. © 2003 Wiley–Liss, Inc.
Use of balloon pull‐through technique to assist in CardioSEAL device closure of patent foramen ovale
Authors: Chintala Kavitha , Turner Daniel R. , Leaman Stephanie , Rodriguez‐Cruz Edwin , Wynne Joshua , Greenbaum Adam , Forbes Thomas J.
Published: August 2003

CardioSEAL device closure of patent foramen ovale (PFO) has been advocated for the treatment of patients with cryptogenic stroke. Using the standard delivery technique, partial deployment of the CardioSEAL device can occur, especially in patients with a thick septum secundum and/or long PFO tunnel. We hypothesized that using a left atrial‐to‐right atrial balloon pull‐through to make the septum primum incompetent would result in improved final device position regardless of septal thickness or tunnel length. Catheterization reports, cineangiograms, and transesophageal echocardiograms of 51 patients who underwent CardioSEAL device closure of PFO between March 2000 and August 2002 were retrospectively reviewed. Group 1 (n = 21) included patients with CardioSEAL placement using the standard technique and group 2 (n = 30) included patients with CardioSEAL placement using the balloon pull‐through technique. There were no differences between the groups in terms of age (43.6 vs. 45.3 years; P = NS), weight (83.3 vs. 89.9 kg; P = NS), septum secundum thickness (6.4 vs. 7.0 mm; P = NS), PFO tunnel length (15.5 vs. 13.1 mm; P = NS), or device size. In group 1, 4/21 (19%) had partial deployment of the CardioSEAL device, while in group 2, no partial CardioSEAL deployment (0/30) was observed. No complications were associated with the balloon pull‐through technique. We conclude that the left atrial‐to‐right atrial balloon pull‐through technique is safe and may allow for better final position of the CardioSEAL device during PFO closure. Catheter Cardiovasc Interv 2003;60:101–106. © 2003 Wiley–Liss, Inc.
Fenestrated Amplatzer device for percutaneous creation of interatrial communication in patients after Fontan operation
Authors: Chatrath Ritu , Cabalka Allison K. , Driscoll David J. , Hagler Donald J.
Published: August 2003

A customized Amplatzer septal device with a 5 mm fenestration was used to create an interatrial communication in two patients with previous Fontan operation and clinical indication for fenestration. At follow‐up, device fenestration was occluded in both patients. In both patients, the device fenestration was reopened and patency maintained by placement of two stents within the communicating channel. Catheter Cardiovasc Interv 2003;60:88–93. © 2003 Wiley–Liss, Inc.
Radiofrequency perforation in the treatment of acquired left pulmonary artery atresia following repair of tetralogy of Fallot
Authors: Kort Henry W. , Balzer David T.
Published: August 2003

Acquired pulmonary artery discontinuity can complicate operative repair of certain congenital heart defects. We describe successful recanalization of acquired left pulmonary artery atresia using radiofrequency energy in a 14‐month‐old child who had previously undergone repair of tetralogy of Fallot with pulmonary atresia. Catheter Cardiovasc Interv 2003;60:79–81. © 2003 Wiley–Liss, Inc.
Transbrachial insertion of an intra‐aortic balloon pump for complex coronary angioplasty
Authors: Noël Bernard M. , Gleeton Onil , Barbeau Gérald R.
Published: August 2003

Transfemoral insertion of intra‐aortic balloon pump (IABP) for hemodynamic support is a useful adjunct in patients undergoing complex percutaneous revascularization procedures. However, this approach is not always possible, particularly in patients with severe occlusive peripheral vascular disease. We describe the first reported case of insertion of IABP through the brachial artery. Catheter Cardiovasc Interv 2003;60:36–39. © 2003 Wiley–Liss, Inc.
Intracoronary radiation to treat in‐stent restenosis in six cardiac transplant patients
Authors: Grise Mark A. , Reilly John P. , Tobis Jonathan M. , Takano Yuzuru , Currier Jesse W. , Kobashigawa Jon A. , Weisz Giora , Moses Jeffrey W. , Leon Martin B. , Yeung Alan , Teirstein Paul S.
Published: August 2003

Transplant vasculopathy significantly limits the survival of cardiac transplant patients and occurs in 50% of patients by 5 years posttransplant. We report our experience with six cardiac transplant patients who underwent intracoronary brachytherapy for in‐stent restenosis. At four centers, six patients underwent intracoronary radiation for in‐stent restenosis. All patients received extended antiplatelet therapy with clopidogrel and aspirin. Follow‐up angiography was performed in all patients. Two of the six patients underwent subsequent target lesion revascularization. Patient 1 presented with total occlusion of her radiated lesion. She had a complex procedure requiring stenting for a dissection after the radiation dwell. Patient 2 had high‐grade restenosis following brachytherapy. Patient 3 had a 50% restenotic lesion. Patients 4, 5, and 6 had follow‐up angiography that showed no evidence of restenosis. There are few good options to treated accelerated transplant vasculopathy. Radiation therapy may be a viable option in this difficult patient population. Catheter Cardiovasc Interv 2003;60:41–44. © 2003 Wiley–Liss, Inc.
ST segment elevation in leads V1 to V3 due to isolated right ventricular branch occlusion during primary right coronary angioplasty
Authors: Acikel Mahmut , Yilmaz Mustafa , Bozkurt Engin , Gürlertop Yekta , Köse Nuri
Published: August 2003

It is rare to observe ST elevation in anterior derivations caused by isolated right ventricular branch occlusion. We described the case with acute inferior and right ventricular myocardial infarction (MI) who developed ST segment elevation in precordial leads V1 to V3 due to isolated right ventricular branch occlusion during primary right coronary angioplasty. Catheter Cardiovasc Interv 2003;60:32–35. © 2003 Wiley–Liss, Inc.
Sonotherapy, antirestenotic therapeutic ultrasound in coronary arteries: The first clinical experience
Authors: Regar E. , Thury A. , van der Giessen W.J. , Sianos G. , Vos J. , Smits P.C. , Carlier S.G. , de Feyter P. , Foley D.P. , Serruys Patrick W.
Published: August 2003

We studied the safety and feasibility of intracoronary sonotherapy (IST) and its effect on the coronary vessel at 6 months. Thirty‐seven patients with stable or unstable angina were included (40 lesions). The indication was de novo lesion (n = 26), restenosis (n = 2), in‐stent restenosis (n = 11), and a total occlusion of a venous bypass graft. After successful angioplasty, IST was performed using a 5 Fr catheter with three serial ultrasound transducers operating at 1 MHz. IST was successfully performed in 36 lesions (success rate, 90%). IST exposure time per lesion was 718 ± 127 sec. During hospital stay, one patient died due to a bleeding complication. At 6‐month follow‐up, one patient experienced acute myocardial infarction, eight patients underwent repeat PTCA. No patient underwent CABG. Late lumen loss was 1.05 ± 0.70 mm with a restenosis rate of 25%. IVUS analysis revealed a neointima burden of 25% ± 11%. IST can be applied safely and with high acute procedural success. Sonotherapy‐related major adverse events were not observed. Late lumen loss and neointimal growth were similar to conventional PTCA approaches. These results justify the initiation of randomized clinical efficacy studies. Catheter Cardiovasc Interv 2003;60:9–17. © 2003 Wiley–Liss, Inc.
Feasibility and safety of day‐case transfemoral coronary stenting
Authors: Dalby Miles , Davies Justin , Rakhit Roby , Mayet Jamil , Foale Rodney , Davies D. Wyn
Published: August 2003

Percutaneous coronary intervention (PCI) is usually followed by overnight observation. In order to increase activity from a limited bed base, we planned to discharge a cohort of patients undergoing uncomplicated PCI procedures on the same day. Seventy patients considered suitable for same‐day discharge underwent PCI procedures and a 100% stent rate was planned with device closure of the arterial access site. Procedural success was achieved in 68 (97%) of patients and 51 (73%) were discharged as day cases. None re‐presented or had clinical complications within 24 hr. Nineteen (27%) were kept in hospital electively for observation. No preprocedural clinical or angiographic characteristics predicted successful or failed day‐case discharge. In selected patients who undergo uncomplicated PCI with stenting and device arterial closure, same‐day discharge appears safe and achievable in about three‐quarters of cases. Catheter Cardiovasc Interv 2003;60:18–24. © 2003 Wiley–Liss, Inc.
Insufficient tissue ablation by rotational atherectomy leads to worse long‐term results in comparison with balloon angioplasty alone for the treatment of diffuse in‐stent restenosis: Insights from the intravascular ultrasound substudy of the ARTIST randomized multicenter trial
Authors: Haager Philipp K. , Schiele François , Buettner Heinz J. , Garcia Eulogio , Bedossa Marc , Mudra Harald , Dietz Ulrich , di Mario Carlo , Reineke Thorsten , Horn Birger , Hoffmann Rainer , Radke Peter W. , Klues Heinrich G. , vom Dahl Juergen
Published: August 2003

The ARTIST trial demonstrated a worse outcome for patients with in‐stent restenosis (ISR) treated with rotational atherectomy (RA) and adjunctive balloon angioplasty (PTCA) as compared to PTCA alone. This intravascular ultrasound (IVUS) substudy compares effects of lumen enlargement and examines reasons for failure of RA in this setting. IVUS (n = 56) was performed after each interventional step and at follow‐up. Volumetric lumen gain measured 79 ± 68 mm3 after PTCA (13 ± 4 atm) as compared to 44 ± 26 mm3 after RA and adjunctive PTCA (7 ± 3 atm; P < 0.0001). RA itself enlarged lumen by only 19 ± 17 mm3 and stent volume was 47% smaller as compared to high‐pressure PTCA. Low‐pressure strategy after RA did not prevent tissue growth during follow‐up (19 ± 25 vs. 36 ± 38 mm3; RA vs. PTCA; P = 0.09). Consequently, net lumen gain after PTCA was 82% higher compared to RA (46 ± 54 vs. 25 ± 24 mm3; P = 0.09). Further stent expansion is the key mechanism to achieve luminal gain by PTCA of ISR. Neointimal ablation by RA has only minor effects. Low‐pressure PTCA does not prevent recurrent tissue growth and failed for treatment of ISR due to insufficient stent expansion. Catheter Cardiovasc Interv 2003;60:25–31. © 2003 Wiley–Liss, Inc.
Interactivity and Automated Process Design
Authors: Fraga E.S. , Wang K. , Salhi A.
Published: August 2003

Jacaranda is a system for automated process design, which has been designed to support interactivity to ensure the maximum effectiveness. Examples demonstrating the potential of an interactive automated design approach are presented in this article. These include heat integrated separation sequence synthesis, reaction/separation with environmental issues, and a process optimization problem with small feasible regions.
Plant‐Wide Integration of Information and Decision Support Systems: Present Tools and Limitations
Authors: Espuña A. , Nougués J.M. , Puigjaner L.
Published: August 2003

Information accessibility has changed the way that chemical process plants are being managed. The traditional pyramidal hierarchy that is usually the core of any management structure is being threatened by the potential of centralized decision‐making covering more and more possibilities. But although present tools may have access to any significant piece of objective information, and can process it at growing speeds, they are still termed as “decision support” systems. Sensible decision‐making is not only the result of knowledge plus information; it is also important to consider the effects of the different factors that are usually embraced by the term “human factors”.
Solution Crystallization – Developments and New Trends
Authors: Ulrich J.
Published: August 2003

There are three clear new trends in solution crystallization. The first is crystallizer control, with the aim of better crystals by means of measuring supersaturation and crystal sizes in‐line/on‐line. The second trend is the molecular modeling of crystals. The focus is on finding “tailor made additives” by computer simulations. The third trend is for a more detailed view and control of polymorphism and pseudo polymorphism of the crystallized substances.
Catalytic and Multiphase Reactors for the Future
Authors: Keurentjes J.T.F. , Goetheer E.L.V. , Gielens F.C. , Kuijpers M.W.A. , Heijnen J.H.M. , van den Broeke L.J.P. , Kemmere M.F. , Vorstman M.A.G.
Published: August 2003

A number of developments leading to sustainable catalytic and multi‐phase reactors are described. For this purpose, traditional solvents are replaced by clean solvent alternatives such as supercritical fluids and aqueous surfactant systems, and processes are intensified using membrane reactors and contacting reactants at a molecular level.
Particle Design Using Supercritical Fluids
Authors: Reverchon E. , Della Porta G.
Published: August 2003

New supercritical fluid based techniques for particle design are reviewed in this article. Particular attention is given to a new and promising technique that uses supercritical fluids to assist atomization processes. Using this new and versatile process, several water soluble compounds that cannot be treated by traditional supercritical fluid based techniques can be successfully micronized.
Spouted Bed Reactors
Authors: Olazar M. , Alvarez S. , Aguado R. , San José M.J.
Published: August 2003

Spouted beds are commonly thought of as being solely of use for processes involving coarse particles (of the order of 1 mm and above). The latest advances on conical spouted beds are discussed in this review. This contact method is especially useful for applications where a vigorous movement of the solid is required, for example, in the handling of solids that are sticky, of irregular texture, or with a large particle size distribution.
Microporous Solid Characterization: Use of Classical and “New” Techniques
Authors: Lozano‐Castelló D. , Cazorla‐Amorós D. , Linares‐Solano A.
Published: August 2003

Gas adsorption techniques constitute the most common approach for the characterization of the pore structure of porous materials, N2 adsorption at 77 K is the most used. It has been demonstrated that CO2 adsorption at 273 K, at sub‐atmospheric pressures, is necessary for the correct characterization of this narrow microporosity.
Fuel Cells, Advanced Reactors and Smart Catalysis: The Exploitation of Ceramic Ion‐Conducting Membranes
Authors: Metcalfe I.S.
Published: August 2003

Membrane reactors are of great interest in the chemical industries because they offer the possibility of improved yields, improved selectivities and more compact plant. However, a significant barrier to their uptake is the unavailability of membrane systems having the required performance at an acceptable cost. In this paper we will explore the use of one class of membrane that has the potential to deliver high performance at reasonable cost. Ion‐conducting ceramic membranes can be used in a wide range of high temperature applications including fuel cells, advanced reactors and even smart catalytic systems.
Two‐Phase Flow with Mass Transfer in Bubble Columns
Authors: Mewes D. , Wiemann D.
Published: August 2003

Bubble columns are widely used in the chemical and biochemical industries. In these reactors a gaseous phase is dispersed into a continuous liquid phase thus the rising bubble swarm induces a circulating flow field. For the dimension of these reactors the local interfacial area and the residence time of the liquid and the gaseous phase are key parameters. In this paper an Euler‐Euler approach is used to calculate the flow field in bubble columns numerically. Therefore a transport equation for the mean bubble volume based on a population balance equation approach is coupled with the balance equations for mass and momentum. The calculations are performed for three‐dimensional, instationary flow fields in cylindrical bubble columns considering the homogeneous and the heterogeneous flow regime. For the interphase mass transfer the physical absorption of the gaseous phase into the liquid is assumed. The back mixing in the gaseous and liquid phase is calculated from the local and time dependent concentration of a tracer.
Performance of a New Mixed Down Pumping Impeller
Authors: Ascanio G. , Foucault S. , Tanguy P.A.
Published: August 2003

A new mixed down pumping impeller was designed and characterized with both Newtonian and non‐Newtonian fluids in terms of the power consumption and mixing times. A non‐intrusive color‐discoloration technique based on a fast acid‐base reaction was used to determine mixing times and to reveal the presence of both segregated and dead zones at low speed. This new geometry gives similar mixing times to those obtained with a radial turbine but with the power requirements of an axial flow impeller. It was demonstrated that segregated regions formed below the impeller are readily destroyed by the pumping action of this new geometry, while the regions formed above the impeller are destroyed by radial discharge, so that shorter mixing times are obtained. The use of the proposed geometry appears to be a good alternative for mixing applications requiring a good dispersion combined with low power consumption.
Nonstationary Simulation Model of Absorber with Falling Film of Suspension
Authors: Gerbeč M. , Stergaršek A. , Kocjančič R.
Published: August 2003

A nonstationary model of SO2 absorption from a gas phase to a countercurrent falling film of absorbing slurry was developed. Laminar, wavy and turbulent film structures were considered based on published information. Resistances to the mass transfer on the gas and the liquid sides of the interphase were considered, together with chemical reactions in the liquid phase. Relevant chemical equilibria in the liquid phase were modeled. Original experimental data on the neutralization reagent dissolution rate presented as a polydispersed two‐phase system of solids and on the rate of dissolved sulfite oxidation were used. The model was verified with experimental data from a laboratory‐scale falling‐film absorber using a single vertical tube under various geometrical and operating conditions, and a very good agreement was found with the experiment. Parametric sensitivity analysis showed the critical parts of the model.
Theoretical Investigation of a Pd‐membrane Reactor for Methanol Synthesis
Authors: Rahimpour M.R. , Ghader S.
Published: August 2003

A numerical study is performed in order to evaluate the performance and optimal operating conditions of a palladium membrane reactor for methanol synthesis. A novel reactor configuration with a Pd wall, which is perm‐selective to hydrogen, has been proposed. In this configuration the reactants are added to the tube side while pure hydrogen is added to the shell side, as a result, the hydrogen diffuses across the membrane from the shell side to the tube side. In this membrane reactor, hydrogen penetrates to the reaction side in order to maintain a suitable hydrogen level in the whole length of the reactor and shift the equilibrium reaction. The effects of different parameters on the methanol output mole fraction were investigated in the co‐current mode. These parameters were membrane thickness, reaction side flow rate, reaction side pressure, shell side pressure and H2/CO2 ratio in the feed.
Monitoring Crystallization Kinetics of Azelaic Acid by in situ FTIR Spectroscopy in Three‐Phase Systems
Authors: Nattkemper A. , Schleiden T. , Migliavacca J.M. , Melin T.
Published: August 2003

The evolution of solid particles during crystallization frequently makes it impossible to measure concentration profiles by conventional sampling. Concentration profiles of the liquid phase can still be measured by coupling an ATR deep‐immersion probe with a FTIR spectrometer. Using this system concentration profiles of azelaic acid initially dissolved in acetone could be obtained. Cooling is accomplished by directly injecting liquid carbon dioxide into the reaction mixture which causes the mixture to be a three‐phase system. Although the system is highly turbulent, CO2 gas bubbles and evolving azelaic acid particles were not observed to influence the IR signal. Four different cooling rates of 4.2, 11.7, 18.5, and 26.1 °C/min were investigated. Concentration data points are obtained every five seconds giving a total of up to one hundred data points depending on the experimental settings. The FTIR absorption spectra are converted to volume‐based concentration profiles by an interpolation type algorithm. Further conversion to mass‐based concentration profiles made it possible to track the exact starting time of the crystallization process. It also eliminates the effect of decreasing temperature on the concentration profiles. By a comparison of all four experiments the detection of sub‐cooling with increasing cooling rates is possible.
Influence of Reaction Kinetics on the Performance of a Chromatographic Reactor
Authors: Herbsthofer R. , Bart H.‐J.
Published: August 2003

In general, the economic use of chromatographic reactors depends on the reaction and separation parameters. In this work, the continuous annular chromatograph as multifunctional reactor (CACR) and the CACR with upstream tube reactor (TUBR + CACR) were investigated.
Sustainable Growth and Chemical Engineering
Authors: Venselaar J.
Published: August 2003

Growth is needed. Connected with economic growth is the concern about our resources, environment, and the effects on human health. Our economy and wealth depend on material resources. Chemistry transforms the resources into the materials and products we need: energy, housing, clothing, food, transport, appliance, and clean water. Economic growth presently implies growth in use of resources what cannot be sustained on the long run – a challenge for society as a whole, industry, and chemical engineering in particular.
Arsen‐Metabolismus im Menschen: Kopplung von Festphasenmikroextraktion und GC‐MS
Authors: Sur Robin , Hajimiragha Hossein , Begerow Jutta , Dunemann Lothar
Published: August 2003

Eine neuartige Kopplungstechnik für die Bestimmung von Hintergrundkonzentrationen an Trimethylarsinoxid (TMAO) und anderen Metaboliten des Arsens im menschlichen Urin wurde entwickelt. Die Ergebnisse liefern neue Einblicke in den Arsen‐Metabolismus im menschlichen Organismus bei umweltbedingter Arsen‐Exposition.
Proteine der Photosynthese: Aus Licht wird Leben
Authors: Harrer Roswitha
Published: August 2003

Photosynthesis is based on a fascinating interplay between proteins, pigments and membranes. The cleavage of water molecules takes place in photosystem II which is excited by light. Recent structure elucidation of photosystem II helped in understanding the electron transfer reaction but the water splitting mechanism is still not solved. The light energy is stored in ATP, which is synthesized by the ATP Synthase, a molecular motor. Its membrane part, the c‐ring, mediates the transfer of protons. Structure and function of ATP Synthase are currently under intensive investigation.