bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vivo validation of an experimental adaptive quantitative coronary angiography algorithm to circumvent overestimation of small luminal diameters
Authors: Keane David , Gronenschild Ed , Slager Cornelis , Ozaki Yukio , Haase Jürgen , Serruys Patrick W. 
Published: March 2007

AbstractThe reliability of quantitative coronary angiography (QCA) measurements is of fundamental importance for the study and practice of interventional cardiology. In vivo validation results have consistently reported a tendency for QCA systems to overestimate small luminal diameters. Such a systematic error may result in the underestimation of luminal gain during intracoronary procedures and in the underestimation of progression of coronary artery disease during longitudinal studies.We report the in vivo validation results of an experimental adaptive edge‐detection algorithm that was developed to reduce overestimation of small luminal diameters by incorporating a dynamic function of variable kernel size of the derivative operator and variable weighting of the first and second derivatives of the brightness profile. The results of the experimental algorithm were compared to those of the conventional parent edge detection algorithm with fixed parameters.Dynamic adjustment of the edge‐detection algorithm parameters was found to improve measurements of small (lt;0.8‐mm) luminal diameters as evidenced by an intercept of +.07 mm for the algorithm with variable weighting compared to +0.21 mm for the parent algorithm with fixed weighting. A slope of <1 was found for both the parent and experimental algorithms with subsequent underestimation of large luminal diameters.Systematic errors in a QCA system can be identified and corrected by the execution of objective in vivo validation studies and the consequent refinement of edge‐detection algorithms. The overestimation of small luminal diameters may be overcome by the incorporation of a dynamic edge‐detection algorithm. Further refinements in edge‐detection algorithms will be required to address the issue of underestimation of large luminal diameters before the absolute values derived from QCA measurements can be considered accurate over the full range of clinically encountered luminal diameters. © 1995 Wiley‐Liss, Inc.
Left ventricular false aneurysm: An unusually prolonged natural history
Authors: Bolognesi Roberto , Cucchini Francesco , Lettieri Corrado , Manca Carlo , Visioli Odoardo 
Published: March 2007

AbstractA case of left ventricular false aneurysm of postinfarctual etiology with an unusually prolonged natural history (12 years survival) is reported. A first diagnosis of this rare cardiac complication was made in 1982 on the basis of hemodynamic and echocardiographic results. At that time the patient rejected surgical therapy.Eleven years later the patient came back to our attention after resuscitation from a sudden cardiac death. Hemodynamic and echocardiographic (transesophageal) tests showed a remarkable impairment of left ventricular function and an abnormal enlargement (10 × 8 cm) of a pseudoaneurysmatic cavity full of thrombi. The patient died suddenly in April 1994.We emphasize the unusual, prolonged survival of our patient suffering from an unresected left ventricular false aneurysm of postinfarctual etiology. © 1995 Wiley‐Liss, Inc.
Emergency rotational ablation of a calcified left main coronary artery stenosis in a patient with ischemic induced cardiogenic shock
Authors: Rozenman Yoseph , Lotan Chaim , Weiss A. Teddy 
Published: March 2007

AbstractHigh‐speed rotational ablation is ideal in the treatment of chronic calcified atherosclerotic lesions. This report describes an elderly woman with a prior history of coronary artery bypass surgery, who developed cardiogenic shock secondary to occlusion of a saphenous vein graft to the obtuse marginal branch of the circumflex coronary artery. Her left main coronary artery was heavily calcified and almost completely occluded. She was treated successfully by high‐speed rotational ablation of her left main stenosis. © 1995 Wiley‐Liss, Inc.
Fatal aortic rupture following balloon angioplasty of aortic restenosis in aortoarteritis
Authors: Sharma Satyavan , Pinto Robin Joseph 
Published: March 2007

AbstractWe report a case of fatal aortic rupture following balloon dilation in a young female with aortoarteritis in whom restenosis of the aorta was observed 16 years after a patch aortoplasty operation. To the best of our knowledge, this complication has not been reported in aortoarteritis, although such instances have been reported in recoarctation. This unfortunate experience leads us believe that aortic segment in operated cases may be resistant to balloon dilation and vulnerable to rupture. In such cases, balloon angioplasty should either be avoided or performed with extreme caution. A sequential balloon dilation technique starting with a smaller balloon may be helpful in avoiding this complication. © 1995 Wiley‐Liss, Inc.
Is acoustic shadowing at intracoronary ultrasound always the marker of intramural calcium accumulation?
Authors: Depré Christophe , Havaux Xavier , Hanet Claude , Vanoverschelde Jean‐Louis J. 
Published: March 2007

AbstractIntracoronary ultrasound (ICUS) is increasingly used at catheterization to assess more precisely the severity of luminal narrowing, to delineate the composition of the atherosclerotic plaque, and to select the optimal therapeutic strategy. With this technique, a drop in signal intensity, known as acoustic shadowing, is usually equated with the presence of calcium in the plaque. We report the study of an atherosclerotic coronary artery showing intense acoustic shadowing at ICUS, but in which no calcium deposition could be evidenced at postmortem pathological analysis. This observation suggests a word of caution with regard to considering acoustic shadowing at ICUS as the reflection of superficial calcium deposition within a vessel wall. © 1995 Wiley‐Liss, Inc.
Long‐term effects of balloon coarctation angioplasty on arterial blood pressure in adolescent and adult patients
Authors: Schräder Rainer , Bussmann Wulf‐Dirk , Jacobi Volkmar , Kadel Christoph 
Published: March 2007

AbstractIn patients with coarctation of the aorta arterial hypertension frequently persists when surgical repair is performed after age 20 years. There are little data on the long‐term effect of angioplasty and the question remains to be determined whether hypertension is sufficiently treated by this procedure.Twenty‐nine consecutive patients (9 females and 20 males) 14 to 54 years old (median, 25) underwent angioplasty for native coarctation of the aorta. Twenty‐five patients (86%) had pre‐existing systolic arterial hypertension (>140 mm Hg). The mean peak systolic pressure gradient decreased from 62 ± 18 to 21 ± 13 mm Hg immediately after angioplasty. At hospital discharge 13 patients still had hypertension. After a mean follow‐up interval of 4.0 years (range, 0.3–9.5) the residual peak pressure gradient was 14 ± 13 mm Hg. Blood pressure was normal without antihypertensive therapy in 23 patients (79%). In the six hypertensive patients the pressure gradients were 7,13,30,30,35, and 60 mm Hg. One patient died 8 months after angioplasty and another underwent surgery for aortic aneurysm.Although this was an uncontrolled study the data suggest that normalization of blood pressure may occur more frequently after angioplasty than after surgery in adolescents and adults with native coarctation. © 1995 Wiley‐Liss, Inc.
Transcatheter closure of residual atrial septal defect following implantation of buttoned device
Authors: Zamora Rolando , Lax Daniela , Donnerstein Richard L. , Lloyd Thomas R. 
Published: March 2007

AbstractWe report a case in which residual shunting after a buttoned device occlusion of atrial septal defect (ASD) was eliminated by transcatheter retrieval of a portion of the device, followed by implantation of a second device. This method may be helpful for those patients with residual ASDs who decline surgical device retrieval and defect closure. © 1995 Wiley‐Liss, Inc.
Transcatheter closure of oversized persistent ductus arteriosus by simultaneous delivery of two rashkind umbrella devices
Authors: Sievert H. , Moor T. , Ensslen R. , Spies H. , Scherer D. 
Published: March 2007

AbstractTranscatheter closure of persistent ductus arteriosus (PDA) with a diameter of >9 mm is considered to be impossible or at least difficult with the occlusion systems that are currently available. We report a simple technique for occluding oversized PDAs with two Rashkind umbrellas introduced simultaneously. Using this technique, a large PDA with a diameter of 13 mm was successfully occluded in a 40‐year‐old man. Complete closure without residual shunt was documented by echocardiogram and angiogram. © 1995 Wiley‐Liss, Inc.
Can coronary flow parameters after stent placement predict restenosis
Authors: Hong Mun K. , Wong S. Chiu , Mintz Gary S. , Popma Jeffrey J. , Kent Kenneth M. , Pichard Augusto D. , Satler Lowell F. , Leon Martin B. 
Published: March 2007

AbstractIntracoronary stent was used to treat a dissection resulting from balloon angioplasty. Coronary flow parameters measured with Doppler Flowire pre‐ and post‐stenting suggested abnormal coronary flow even after stenting. The patient returned 4 months later with an instent restenosis. This case suggests the intriguing possibility of coronary flow parameters obtained immediately after new device angioplasty in predicting restenosis. © 1995 Wiley‐Liss, Inc.
Concurrent balloon dilatation of rheumatic trivalvular stenosis
Authors: Goel Saurabh I. , Desai Dhruman M. , Shah Leelam S. 
Published: March 2007

AbstractA 26‐year‐old male presented with increasing dyspnoea and exertional palpitations of 2 months duration. The clinical and echo evaluation revealed severe stenosis of the mitral, aortic, and tricuspid valves. Concurrent percutaneous dilatation of all three valves was done as a single stage procedure. The procedure was successful and produced significant clinical and haemodynamic improvement. The mitral and tricuspid valves were dilated using the same Inoue balloon, whereas the aortic stenosis was dilated using the pigtail tipped balloon. © 1995 Wiley‐Liss, Inc.
Diffuse vasospasm following stenting of a free gastroepiploic artery graft: Resolution with balloon angioplasty and intensive medical therapy
Authors: Feld Steven , Kjellgren Olle , Sweeney Michael S. , Drtil Alexander , Anderson H. Vernon , Schroth George , Tauss Nancy , Taegtmeyer Heinrich , Smalling Richard W. 
Published: March 2007

AbstractVasospasm following balloon angioplasty of gastroepiploic artery bypass grafts can be prevented or reversed with vasodilators. In our patient, stent deployment for ostial stenosis of a free gastroepiploic artery graft was accompanied by severe, diffuse spasm and a change in graft configuration that required both intensive medical therapy and balloon angioplasty for resolution. © 1995 Wiley‐Liss, Inc.
Successful treatment of chronic total peripheral occlusions that failed conventional techniques using the stiff backend of the glidewire™
Authors: Kjellgren Olle , Feld Steven , Loyd Dan , Schroth George , Anderson H. Vernon , Smalling Richard W. 
Published: March 2007

AbstractThe vast majority of failures of transcatheter interventions in patients with peripheral vascular disease are due to inability to cross the lesion with a guidewire. Although the use of the GlidewireTM has clearly improved the success rate, failures with especially chronic total occlusions still occur. We describe a new technique using the very stiff backend of the Glidewire, which we have found very successful, when conventional techniques fail in crossing highly resistant lesions. © 1995 Wiley‐Liss, Inc.
A pulse programmer for nuclear magnetic resonance spectrometers
Authors: Odebrecht C.C. , Tagle D. , Zuriaga F.B. , Steren C.A. 
Published: March 2007

AbstractA pulse programmer (PP) designed to control a nuclear magnetic resonance (NMR) spectrometer is reported on. The heart of the PP is a computer programmable logic device (CPDL) that provides flexibility to the design and, at the same time, reduces the number of electronics components needed and the dimensions of the printed circuit board. The PP works as follow: first, a pulse sequence defined by a set of instructions is loaded into the RAM memory of the PP. Then, when the process is started, the instructions are, one by one, read, decoded, and executed. Four types of instructions (functions) were defined: PRINT A, PRINT B, WAIT, and STOP. PRINT A and PRINT B change the status of the output channels A and B, respectively, WAIT generates a time delay, and STOP terminates the sequence. The output ports A and B have 14 channels each, and the shortest pulse and resolution are both 200 ns. The design of the PP is versatile, and new functions can be added through software without modifying the printed circuit board. To control the PP from a personal computer, a program named PulseJr was developed. It contains a graphical user interface (GUI) and pulse sequences can be drawn on the monitor screen with the mouse of the computer. Once the pulse sequence is sketched, clicking a button the program compiles the pulse sequence, generates the set of instructions, loads them into the RAM memory of the PP, and starts the pulse sequence. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 127–131, 2007.
Coherence pathway selection by cogwheel phase cycling in liquid‐state NMR
Authors: Zuckerstätter Gerhard , Müller Norbert 
Published: March 2007

AbstractCoherence selection as an integral element of most multipulse NMR methods also represents a bottleneck to the efficiency of multidimensional NMR methods. In particular, phase cycling often requires total scan numbers in excess of signal‐to‐noise demands. M. H. Levitt and coworkers have recently introduced cogwheel phase cycling in solid‐state NMR, which improves on this problem. In this article we recapitulate the principles of coherence selection in multipulse and multidimensional NMR. The fundamental differences between various coherence selection strategies are discussed, and examples of implementing cogwheel phase cycling in liquid‐state NMR experiments commonly used for biopolymers are given. Design guidelines are suggested for incorporating cogwheel phase cycles into other pulsed NMR techniques. For experiments with multiple coherence transfer steps, cogwheel phase cycling is more efficient in spectrometer time usage than traditional nested phase cycling, as the scan numbers can be adjusted in smaller steps. Even compared with pulsed field gradient selection methods advantages exist, especially for fast relaxing resonances. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 81–99, 2007.
Human circulating specific antibody‐forming cells after systemic and mucosal immunizations: differential homing commitments and cell surface differentiation markers
Authors: Quiding‐Järbrink Marianne , Lakew Mekuria , Nordström Inger , Banchereau Jacques , Butcher Eugene , Holmgren Jan , Czerkinsky Cecil 
Published: March 2007

AbstractCirculating spontaneous antibody‐secreting cells (ASC) induced by mucosal and systemic immunizations in human volunteers have been characterized with respect to differentiation stage and homing commitments. Irrespective of the immunization route, the large majority of ASC co‐expressed CD19 and HLA‐DR, which are normally lost during the transition of plasmablasts to plasmocytes, as well as CD38, a marker of activated B cell blasts, expressed also by plasmocytes. However, these cells expressed neither CD28, a molecule acquired by plasmocytes, nor CD22 and CD37, which are lost during the transition of plasmablasts to plasmocytes. Therefore, the large majority of ASC found in peripheral blood after oral and parenteral immunizations are terminally differentiated B cells, but not fully differentiated plasmocytes. As a whole, the mucosally derived ASC population seemed to be more homogenously differentiated. CD25 was detected on few ASC, whereas ASC expressing CD71 were more numerous, especially among systemically derived ASC. Almost all ASC expressed the adhesion molecules CD44 and α4‐integrins, irrespective of immunization route. However, virtually all systemically derived ASC expressed L‐selectin, recognizing the peripheral lymph node addressin, whereas only a minority of mucosally induced blood ASC expressed L‐selectin. These studies are the first to demonstrate in humans that circulating precursors of mucosal B cell immunoblasts utilize organ‐specific recognition mechanisms distinct from those of corresponding systemic B cells and appear to be more advanced in the B lineage maturation pathway. Specialization of receptor expression could explain both the unification of immune responses in diverse mucosal sites and the physiologic segregation of mucosal from non‐mucosal immune mechanisms in humans.
Expression of cell interaction molecules by immature rat thymocytes during passage through the CD4+8+ compartment: developmental regulation and induction by T cell receptor engagement of CD2, CD5, CD28, CD11a, CD44 and CD53
Authors: Mitnacht Rita , Tacke Michael , Hünig Thomas 
Published: March 2007

AbstractRat thymocytes of the T cell receptorlow (TcRlow) CD4+8+ subset which is the target of repertoire selection are heterogeneous with respect to expression of the cell interaction (CI) molecules CD2, CD5, CD11a/CD18 (LFA‐1), CD28 and CD44. We show that this heterogeneity is due to the developmental regulation of these CI molecules during passage through the CD4+8+ compartment, and to up‐regulation by TcR engagement. Thus, cohorts of CD4+8+ cells differentiating synchronously in vitro from their direct precursors, the immature CD4−8+ cells, were homogeneous with regard to CI molecule expression. Upon entry into the CD4+8+ compartment, they expressed relatively high levels of CD2 and CD44, and moderate levels of CDS, CD28 and CD11a. CD2, CD28 and CD44 were slightly down‐regulated during the following 2 days, whereas CD5 slightly increased and CD11a remained constant. TcR stimulation using immobilized monoclonal antibodies resulted in rapid and dramatic up‐regulation of CD2, CD5 and CD28 and, to a lesser extent, of CD11a and CD44. Finally CD53, a triggering structure absent from unstimulated CD4+8+ thymocytes was also rapidly induced by TcR stimulation. Inclusion of interleukin (IL)‐2, IL‐4, or IL‐7 in this in vitro differentiation system did not affect the levels of CI molecules studied. Since the high levels of CI molecules induced by TcR‐stimulation correspond to those found in vivo on TcRintermediate thymocytes known to be undergoing repertoire selection, these results suggest that upregulation of CI molecules by TcR engagement provides a mechanism by which thymocytes that have entered the selection process gain preferential access to further interactions with stromal and lymphoid cells in the thymus.
CD28 functions as an adhesion molecule and is involved in the regulation of human IgE synthesis
Authors: Life Paul , Aubry Jean‐Pierre , Estoppey Sandrine , Schnuriger Valerie , Bonnefoy Jean‐Yves 
Published: March 2007

AbstractActivated T cells induce IgE switching in B cells via a combination of lymphokines and direct T:B cell contact. As CD28‐deficient mice have reduced basal levels of IgG1 and IgG2a and diminished Ig class switching, we investigated whether the CD28/B7.1 (CD80) ligand pairing might also be involved in human IgE regulation. Co‐incubation of an allergen‐specific, human T cell clone with tonsillar B cells caused a marked up‐regulation of CD28 expression, whereas, in contrast, CD45 RB expression was unaffected. To test whether blocking the CD28:B7.1 interaction affected IgE synthesis, a dialyzed anti‐CD28 monoclonal antibody (mAb) was added to cultures containing tonsillar B cells, pre‐activated T cell clones and interleukin‐4. Anti‐CD28 treatment caused a reproducible, dose‐dependent inhibition of IgE, but not IgG synthesis that was accompanied by a visible decrease in cell aggregate formation. Conversely, an anti‐B7.1 mAb had no effect in this system. The effect of blocking CD28‐ligand interactions on lymphocyte adhesion was formally assessed on human T cell clones and B cell lines using dual intracellular staining and flow cytometry. Co‐incubation with an anti‐CD28 mAb, but not control IgG or anti‐B7.1 mAb, resulted in a marked impairment of conjugate formation that correlated well with T cell surface expression of CD28. Using this system we found that an anti‐CTLA‐4 mAb but not an anti‐B7.2 mAb inhibited T:B cell conjugate formation. Lastly, in addition to a direct effect of anti‐CD28 mAb on conjugate formation, 14‐day culture of T and B cells in the presence of anti‐CD28 caused a marked decrease of ICAM‐1 (CD54) expression on aggregated lymphocytes. In contrast, LFA‐1 (CD18) expression was unaffected. We, therefore, conclude that the T cell co‐stimulatory molecule CD28 is involved in the regulation of IgE synthesis in vitro. CD28 may act to a limited extent as an adhesion molecule, though apparently not by pairing with B7.1 or B7.2. It is more likely that ligation of CD28 under certain conditions modulates the expression of other T and B cell surface molecules.
Intracellular processing and presentation of T cell epitopes, expressed by recombinant Escherichia coli and Salmonella typhimurium, to human T cells
Authors: Verjans Georges M. G. M. , Janssen Riny , Uytdehaag Fons G. C. M. , van Doornik Claudia E. M. , Tommassen Jan 
Published: March 2007

AbstractVaccines based on recombinant attenuated bacteria represent a potentially safe and effective immunization strategy. A carrier system was developed to analyze in vitro whether foreign T cell epitopes, inserted in the outer membrane protein PhoE of Escherichia coli and expressed by recombinant bacteria, are efficiently processed and presented via human leukocyte antigen (HLA) class I and II molecules by bacterial infected human macrophages. A well‐defined HLA‐B27‐restricted cytotoxic T cell (CTL) epitope and an HLA‐DR53 restricted T helper (Th) epitope of the fusion protein of measles virus were genetically inserted in a surface‐exposed region of PhoE, and the chimeric proteins were expressed in E. coli and Salmonella typhimurium. Macrophages infected with both recombinant bacteria presented the Th epitope to the specific CD4+ T cell clone, but failed to present the CTL epitope to the specific CD8+ T cell clone. Presentation of the Th epitope by the infected macrophages was inhibited by cytochalasin D, indicating that phagocytic processing of intact bacteria within infected macrophages was essential for antigen presentation via HLA class II. Presentation of the Th epitope to the CD4+ T cell clone by infected macrophages was blocked by brefeldin A and cycloheximide, indicating the requirement of nascent HLA class II molecules for presentation. The efficiency of macrophages to process and present the inserted Th epitope was similar for both the recombinant E. coli and S. typhimurium strains.