bluuebunny/crossref_metadata_2025 huggingface dataset:
Bailout techniques for failed coronary angioplasty using 6 french guiding catheters
Authors: Kiemeneij Ferdinand , Laarman Gert Jan
Published: March 2007

Coronary angioplasty (PTCA) through 6 French (F) guiding catheters is feasible, although acute or threatened closure following coronary artery dissections may occur. This report describes our experience with the treatment of suboptimal results in 13 patients from a population of 144 patients who had PTCA through 6F guiding catheters. Patients were treated with a new low profile autoperfusion catheter (ACS®, Flowtrack40™) or with Palmaz Schatz stents, advanced through 6F guiding catheters. PTCA was performed via the radial artery in 11 pts (85%) or via the femoral artery in two patients (15%). In two patients, (15%) PTCA was complicated by an dissection associated with complete loss of flow (TIMI 0) and a dissection was considered to lead to abrupt closure in the remaining 11 patients (85%), despite the presence of normal flow. A Flow‐track40™ perfusion catheter was successfully applied in three of four patients. In one patient a persisting dissection after restoration of flow by a perfusion catheter was treated with three Palmaz Schatz stents. Implantation of Palmaz Schatz stents was attempted as primary technique in nine patients. In one patient the stent could not cross a dissection in the proximal LAD via the radial artery. With an 8F system via the femoral artery, two stents could successfully be deployed with the stent delivery system. In another patient the stent could not be advanced across a subtotal residual stenosis in a tortuous left anterior descending coronary artery. Despite normal antegrade flow and emergency bypass surgery, this patient developed a non‐Q‐myocardial infarction. In the remaining patients, the clinical course was uncomplicated. With the limitations of the bare stent technique kept in mind, applying bailout techniques such as perfusion balloons and implantation of bare Palmaz Schatz coronary stents should be considered for improvement of suboptimal angioplasty results in a selected group of patients after PTCA with 6F guiding catheters. © 1994 Wiley‐Liss,Inc..
Should we avoid ostial implantations of wiktor stents?
Authors: Chalet Yann , Panes François , Chevalier Bernard , Monassier Jean‐Pierre , Spaulding Christian , Lancelin Bernard , Elkouby Arie
Published: March 2007

Complications arising during stent implantations in coronary arteries have been reduced by technological progress and the accumulated experience of interventional cardiologists. Retrospective and prospective randomized studies with several types of stents are currently available and show improved short and mid‐term results. Wiktor stent provides increased flexibility for ease of implantation particularly in curved lesions. However, the flexibility of the Wiktor stent is also associated with low resistance in the longitudinal axis. We report four cases (in 4 out of 6 ostial lesions treated and 4 out of 43 Wiktor stents implanted during a 9‐month period) in which stents have become unraveled during procedures on ostial lesions (2 saphenous venous grafts and 2 native coronary arteries). Death occurred in one case and one patient was treated by emergency coronary bypass surgery. In three cases the distal extremity of the guiding catheter streched the stent meshes during the final control angiograms, and in one case the stent was stretched during withdrawal of the deflated balloon into the guiding catheter. We believe that it is preferable to avoid using this stent in ostial lesions. © 1994 Wiley‐Liss,Inc..
Percutaneous mitral commissurotomy for severe mitral stenosis during pregnancy
Authors: Kalra Gurcharan S. , Arora Ramesh , Khan Javed A. , Nigam Madhuri , Khalillulah M.
Published: March 2007

Percutaneous mitral commissurotomy was performed in 27 pregnant females aged 24.9 ± 3.14 years (range 20–30 years) with severe mitral stenosis at 22.2 ± 4.3 weeks (range 18–32 weeks) of gestation. All patients were in New York Heart Association functional class IV at the time of procedure. The procedure was performed using the flow guided Inoue balloon in 25 patients and double balloon technique in 2 patients. Percutaneous mitral commissurotomy was successful in 26 patients. The mitral valve area assessed by Doppler echocardiography (pressure half time) increased from 0.78 ± 0.19 cm2 (range 0.5–1.0 cm2) to 2.2 ± 0.12 cm2 (range 1.9—2.6 cm2) (P <0.001). The mean mitral gradient decreased from 30.5 ± 7.6 mm Hg (range 22.5–41.4 mm Hg) to 6.1 ± 2.6 mm Hg (range 4.2–12.3 mm Hg) (P <0.001). The end diastolic gradient decreased from 28.3 ± 4.2 mm Hg (range 23–37 mm Hg) to 2.8 ± 1.5 mm Hg (range 0–5 mm Hg) (P <0.001). The total fluoroscopy time was 5.6 ± 2.2 min (range 2.7–8.9 min). Mitral regurgitation increased by one grade in 7 patients. One patient developed severe mitral regurgitation with anterior mitral leaflet tear needing immediate mitral valve replacement. Twenty‐six patients improved to New York Heart Association class I after the procedure. Twenty‐four patients had full‐term, normal delivery and gave birth to healthy infants. The patients were followed up for 1–36 months (mean 16.6 ± 7.8 months). All patients were in New York Heart Association functional class I. No patient has shown any evidence of restenosis. The mitral valve area on follow‐up was 2.1 ± 0.21 cm2. The degree of mitral regurgitation remained unchanged. The results of this study indicate that percutaneous mitral commissurotomy is a safe and effective procedure for severe mitral stenosis in pregnancy. There are no immediate detrimental effects of radiation on the fetus, though long‐term effects of this amount of radiation are yet to be ascertained. © Wiley‐Liss, Inc.
Epidural abscess as a complication of coronary angioplasty: A rare but dangerous complication
Authors: Oriscello Ralph G. , Fineman Sanford , Vigario Jose C. , Robertello Michael E.
Published: March 2007

We report a rare case of lumbosacral epidural abscess as a complication of coronary angioplasty in a 56‐year‐old male. We outline the mechanism of the abscess and the need for increased awareness and swift management of this entity. © Wiley‐Liss, Inc.
Radiological quality of coronary guiding catheters: A quantitative analysis
Authors: Herrman Jean‐Paul R. , Keane David , Ozaki Yukio , Boer Ad Den , Serruys Patrick W.
Published: March 2007

Quantitative coronary angiography (QCA) is a validated and widely accepted method to investigate changes in arterial dimension over time. Calibration of measurements is enabled by the use of the coronary catheter as a scaling device. The dimensions and laminar composition of coronary catheters, however, have changed significantly over recent years and the suitability of the current generation of coronary catheters for calibration purposes has not been validated. We therefore recorded 57 coronary guiding catheters on cinefilm, and compared their automated quantitative measurements (Cardiovascular Angiography Analysis System, CAAS) with their true values (precision micrometer). We found an overall underestimation of quantitatively derived dimensions, ranging from −8.9 to +4% for water‐filled catheters and from −15.5 to −3.9% for contrast‐filled catheters. In conclusion, while the current generation of coronary guiding catheters shows a wide variety in radiological quality, it can be clearly detected by the CAAS system, and is suitable for calibration of QCA measurements (with the exception of the DVI atherectomy catheter), provided that calibration is done on contrast‐empty catheters. © Wiley‐Liss, Inc.
Catheter sizes for quantitative coronary arteriography
Authors: Reiber Johan H. C. , Jukema Wouter , van Boven Ad , van Houdt Ronald M. , Lie Kong I. , Bruschke Albert V. G.
Published: March 2007

In quantitative coronary arteriography (QCA), the outer diameter of the contrast catheter is used almost exclusively as the calibration device. Since the true outer diameter of these catheters are smaller than the French sizes listed by the manufacturer, it has been advocated to measure the actual sizes with a precision micrometer. However, this represents a significant effort in the organizations of the QCA Angiographic Core Laboratories and of the participating cardiac catheterization laboratories. In the Dutch REGRESS trial on regression/progression of coronary artery disease, we have measured a total of 2,104 catheters from four different manufacturers. In 2,048 of the 2,104 catheters the variabilities in the measurements were 0.02–0.03 mm, which represents an error of only 1% of the average catheter sizes. In the remaining 56 catheter measurements, the variability was 0.04 mm. From these data we may conclude that from now on the stated mean values can be used for calibration purposes. This has important practical consequences for running clinical trials and QCA Core Laboratory operations. © Wiley‐Liss, Inc.
Transesophageal echocardiography assisted retrieval of embolized inferior vena cava stent
Authors: Kamalesh Masoor , Stokes Kenneth , Burger Andrew J.
Published: March 2007

A 32‐year‐old male with Budd‐Chiari syndrome and stenosis of the inferior vena cava presented to the hospital with severe abdominal pain. Two contiguous, 14 mm, overlapping (joined) Palmaz stents were placed across the area of stenosis in the inferior vena cava. The stents later embolized to the left pulmonary artery and were retrieved nonsurgically over a Grollman balloon catheter with transesophageal echocardiographic assistance. This case report highlights the advantages and limitations of transesophageal echocardiographic assistance in such a procedure. © Wiley‐Liss, Inc.
A single center randomized trial assessing use of a vascular hemostasis device vs. conventional manual compression following ptca: What are the potential resource savings?
Authors: Slaughter Pamela M. P. , Chetty Rajendra , Flintoft Virginia F. , Lewis Sheldon , Sykora Kathy , Beattie Dorothy M. , Fscai Leonard Schwartz
Published: March 2007

We undertook a randomized controlled trial comparing VasoSealTM, a collagen vascular hemostasis device (VHD), with manual compression to assess its role and potential cost savings in the PTCA population. Of 460 patients, 359 were excluded due to clinical instability (30%), groin problems (18%), suboptimal PTCA result (15%), and other reasons (37%). The remaining 101 patients were randomized to either VHD (51) or manual compression (50). Hemostasis time, time to ambulation, duration of hospital stay, and nursing time and intensity were significantly reduced in the VHD group. There were no major groin complications in either treatment arm but there was a trend toward more minor groin complications in the VHD patients. The application of VasoSealTM reduced resource use in this randomized study and may translate into significant cost reductions in the general coronary angioplasty population.
Successful repair of combined septal and biventricular free wall rupture after acute myocardial infarction
Authors: Blau William , Ong Lawrence , Stelzer Paul E. , Subramanian Valavanur A.
Published: March 2007

The following case is the first report of successful repair of combined left and right ventricular free wall and ventricular septal rupture. Reports of left ventricular free wall and septal rupture and reports of right ventricular free wall and septal rupture have been published both with and without successful surgical repair. This case demonstrates the presence of left and right ventricular free wall rupture along with septal rupture based upon cardiac catheterization and operative findings. In spite of her severe mechanical complications and prolonged hospital course, the patient is completely functional 1 year after surgical repair.
Right ventricular infarction following percutaneous coronary rotational atherectomy
Authors: Hetterich Frank S. , McEniery Paul T.
Published: March 2007

We describe a case of right ventricular infarction complicating percutaneous coronary rotational atherectomy of sequential calcified right coronary artery lesions. Right ventricular infarction resulted from occlusion of two right ventricular marginal branches during successful atherectomy of the right coronary artery.
Techniques for palmaz‐schatz stent deployment in lesions with a large side branch
Authors: Nakamura Shigeru , Hall Patrick , Maiello Luigi , Colombo Antonio
Published: March 2007

Palmaz‐Schatz coronary stent implantation in lesions with a large side branch are reported. The first case describes how to manage plaque shifting after stent implantation. The second and third cases demonstrate a kissing balloon predilatation and stent dilatation technique of a bifurcational lesion. The final case demonstrates a stent implantation technique through the stent struts of a previously deployed stent.
Clinical application of a new palmaz‐schatz coronary stent delivery system with a short (8 mm) nonarticulated stent
Authors: Wong Philip H. C. , Wong C. M. , Ko Patrick T. H.
Published: March 2007

The standard Palmaz‐Schatz coronary stent delivery system (SDS), with a 15 mm articulated stent and a 5F protective sheath, is relatively rigid and high in profile. Its use is contraindicated in vessels where there is severe tortuosity proximal to or in the lesion itself. Recently a new SDS, with a short (8 mm) nonarticulated stent, has become available. We present three patients with complex coronary anatomy solved with this new SDS. The first patient had a distal stenosis in an extremely tortuous and diffusely diseased right coronary artery (RCA). The second patient had a severe proximal RCA stenosis occurring at a bend of more than 90 degrees. The third patient had a very long stenosis of the left anterior descending coronary artery involving the ostium, requiring multiple tandem stenting. The availability of this short stent will greatly expand the clinical application of intracoronary stenting to patients with complex coronary anatomy.
Effect of data compression on quantitative coronary measurements
Authors: Koning Gerhard , Van Meurs Bert A. , Haas Hein , Reiber Johan H. C.
Published: March 2007

Digital coronary and left ventricular angiography demand high transfer rates and very large data storage if all the clinical data are to be archived. If appropriate compression schemes were available without compromising the quality and resolution of the image data, such demands could be lessened. In this study we compared the influence of different compression factors of the Adaptive Real Time Image Compression (ARTIC) scheme used on the Philips DCI‐SX systems on coronary measurements assessed with the Automated Coronary Analysis (ACA) package.

Loss‐free acquired images of size 5122× 8 bits, which had been stored digitally on tape, were reloaded into the DCI with compression factors of 2, 3, and 4; only the factor 2 is loss free. To evaluate the effect of the different data compressions on the accuracy of the measurements, the diameters of a vessel phantom (tube sizes ranging from 0.687 to 5.062 mm) were determined. To evaluate the reproducibility of the results, the intraobserver variability was determined for the different compression factors from 40 coronary obstructions. The differences in the reference diameter measurements of the vessel phantom were ‐0.03 ± 0.06 mm, 0.01 ± 0.07 mm, and 0.04 ± 0.08 mm for the compression factors 2 (loss free), 3, and 4, respectively. The results were not statistically significantly different.

The intraobserver variabilities in the obstruction diameter measurements of the coronary obstructions were ‐0.04 ± 0.13 mm, 0.00 ± 0.14 mm, and 0.02 ± 0.13 mm for the compression factors 2, 3 and 4, respectively. The intraobserver variabilities in the reference diameter measurements were ‐0.02 ± 0.12 mm, 0.01 ± 0.09 mm, and 0.03 ± 0.09 mm for the compression factors 2,3, and 4, respectively. The intraobserver variabilities of the percent diameter stenosis were 0.96 ± 4.19%, ‐0.01 ± 4.88%, and ‐0.04 ± 4.68% for the compression factors 2,3, and 4, respectively. None of these differences were statistically significant.

Both from a qualitative and quantitative point of view, data compression factors 3 and 4 are acceptable in digital coronary arteriography.
Acute myocardial infarction during coronary angioplasty associated with heparin‐induced thrombocytopenia
Authors: Gupta Bhavdeep K. , Savage Michael P. , Brest Albert N.
Published: March 2007

Heparin‐induced thrombocytopenia is a well‐recognized complication after cardiac or vascular surgery, but it has not been previously reported during percutaneous coronary interventions. This case study describes a patient who developed an acute myocardial infarction during coronary angioplasty in association with the abrupt onset of heparininduced thrombocytopenia. Since balloon angioplasty achieved a satisfactory angiographic result with a widely patent epicardial vessel, it is postulated that acute myocardial infarction in this patient may have been caused by platelet aggregation and activation resulting in distal small vessel thrombosis and spasm. © 1995 Wiley‐Liss, Inc.
Effects of chronic β‐blockade on rest and exercise hemodynamics in mitral stenosi
Authors: Ashcom Thomas L. , Johns Joseph P. , Bailey Steven R. , Rubal PhD Bernard J.
Published: March 2007

β‐blocker therapy for mitral stenosis is controversial. This study compares right and left heart hemodynamics at rest and supine submaximal exercise in patients (n = 7) receiving chronic β‐antagonists with untreated patients (n = 17) matched for age (mean ± SD = 51 ± 12 years) and valve area (0.7 ± 0.2 cm2/m2). Little benefit was observed with treatment at rest. Although pulmonary capillary wedge pressures (PCWP) were lower during exercise in the β‐blocker group (22±4 vs. 31 ± 9 mmHg; P>0.05), exercise performance was not enhanced and cardiac output response during exercise was reduced (control = 41% increase vs. 12% for β‐blockade). PCWP rose rapidly when diastolic filling periods were >300 msec in both groups. Pulmonary capillary wedge pressure was found to be a nonlinear functions (P<0.001) of diastolic filling period (PCWP = 15.9 + 5.84 × 105/dfp2). These data suggest that there is a critical heart rate in patients with mitral stenosis above which hemodynamic compromise rapidly occurs. © 1995 Wiley‐Liss, Inc.

This article is a US Government work and, as such, is in the public domain in the United States of America.
Physiological significance of a proximal coronary artery stenosis on a distal intramyocardial bridge: Coronary flow velocity patterns pre‐ and post‐angioplasty
Authors: Tobias S. Leslie , Videlefsky Searle W. , Misra Vijay K.
Published: March 2007

The angiographic incidence of intramyocardial bridging (MB) is 0.7–4.5% [Angelini et al.: Prog Cardiovasc Dis 25:75–88, 1983]. Morphological and physiological patterns of MB have recently been described, observing coronary flow velocity patterns, intravascular ultrasound, and angiography [Flynn et al.: Cathet Cardiovasc Diagn 32:36–39, 1994; Ge et al.: Circ Res 89:1725–1732, 1994]. We describe a reversal of the normal flow velocity characteristics within a MB, due to a hemodynamically significant stenosis in the proximal left anterior descending artery (LAD). After successful percutaneous transluminal coronary angioplasty (PTCA) of the proximal LAD stenosis, there was normalization of the flow velocity pattern within the MB and the appearance of a spike and dome pattern distal to the MB. © 1995 Wiley‐Liss, Inc.
Coronary angioplasty to relieve a kinked venous bypass conduit
Authors: Broderick Thomas M. , Wolf Randall K.
Published: March 2007

An unusual case of kinking of a freshly placed venous bypass conduit was treated by PTCA and catheter traction. This provided translational movement of the conduit with loss of angulation, relief of kinking, and resumption of normal flow. © 1995 Wiley‐Liss, Inc.
Early hospital discharge after direct angioplasty for acute myocardial infarction
Authors: Hanlon J. Timothy , Combs D. Thomas , McLellan Bruce A. , Railsback Laura , Haugen Sue
Published: March 2007

To determine the feasibility and safety of early hospital discharge after myocardial infarction, we reviewed a 3‐yr experience with direct angioplasty: 204 patients had direct angioplasty with in‐hospital mortality of 3.4%. Of these patients, 125 were discharged < 5 days after infarction and 98% of these were available for 30‐day follow‐up. There was one early death (0.8% mortality), two early readmissions without complications, and three late readmissions. Thus early hospital discharge a mean of 3.4 days after infarction can be achieved in > 60% of patients undergoing direct angioplasty with no significant early complications and excellent 30‐day survival (99.2%). © 1995 Wiley‐Liss, Inc.
Timing, mode, and predictors of death after direct angioplasty for acute myocardial infarction
Authors: Krikorian Raffi K. , Vacek James L. , Beauchamp Gary D.
Published: March 2007

The timing and mechanisms of early (30 day) mortality in 330 consecutive patients treated with direct angioplasty less than 12 hr after onset of myocardial infarction without antecedent thrombolysis were studied. There were 38 deaths (11.5% of pts), with a majority being due to cardiogenic shock (76%). Other causes included acute closure (11 %), death after emergency bypass surgery (5%), ventricular arrhythmias (5%), and respiratory failure (3%). No deaths from stroke or cardiac rupture were seen, in contrast to trials of thrombolytic agents. Most deaths were seen early, with 47% occurring within 1 day, 35% from days 2–7, and 18% from days 8–30. Death from cardiogenic shock was the most common cause of death throughout this period: 83% of deaths in days 0–3, 88% of deaths in days 4–6, and 43% of deaths in days 8–30.

Significant predictors of early death included older age (P <.0001), multi‐vessel disease (P <.05), direct angioplasty failure (P <.05), reduced ejection fraction (P <.0001), and anterior myocardial infarction (P <.0005). Gender, prior myocardial infarction, and prior bypass surgery did not affect mortality.

Cardiogenic shock is the most common cause of early death after direct angioplasty for myocardial infarction. Patients with one or more risk factors for early death may benefit from additional myocardial salvage or revascularization efforts in the early postinfarct period. Certain causes of death after direct angioplasty (cardiac, rupture, stroke) appear to be less common than data reported for lytic therapy for myocardial infarction. © 1995 Wiley‐Liss, Inc.
Retrieval of undeployed intracoronary Palmaz‐Schatz stents
Authors: Wong Philip H. C.
Published: March 2007

Two patients undergoing stent placement with the Palmaz‐Schatz coronary stent delivery system experienced intracoronary stent embolization. Using a two‐wire technique, the stents were successfully removed from the coronary circulation, and this allowed completion of the percutaneous revascularization procedure without any clinical sequelae. These two cases represent the first report of successful percutaneous retrieval of undeployed, retained intracoronary Palmaz‐Schatz stents. © 1995 Wiley‐Liss, Inc.
Systolic rightward displacement of the left anterior descending artery: A novel cineangiographic sign for tricuspid regurgitation
Authors: Shapira Yaron , Wurzel Mordechai , Hirsch Raphael , Teplitsky Igal
Published: March 2007

A new sign for the detection of tricuspid regurgitation (TR) is described. The systolic displacement of the left anterior descending (LAD) artery during coronary angiography in left anterior oblique (LAO) view was quantitively calculated in 3 groups of 20 patients each with either TR, mitral stenosis, or normal coronary arteriograms. The mean LAD displacement in the TR group was significantly rightward compared to the other groups. Uniform rightward displacement of the lower two‐thirds of the LAD had a 90% sensitivity and 90–95% specificity for the presence of TR. Such displacement is probably the angiographic counterpart of the systolic paradoxical septal displacement demonstrated by echocardiography in patients with right ventricular volume overload. There was a positive correlation between the severity of TR and the magnitude of LAD displacement. Attention to the LAD displacement on LAO view may raise suspicion of TR, and indicate its severity. © 1995 Wiley‐Liss, Inc.
Combined percutaneous balloon mitral valvotomy and coronary angioplasty with stent implantation
Authors: Röthlisberger Christian , Kaufmann Urs , Meier Bernhard
Published: March 2007

A patient with symptomatic pliable mitral stenosis and a significant lesion in the right coronary artery underwent combined interventional procedures during a single session. After an uneventful transseptal puncture that allowed full anticoagulation with heparin, a percutaneous transluminal coronary angioplasty was performed, yielding an unsatisfactory result and necessitating stent implantation. Thereafter, mitral stenosis was relieved by percutaneous balloon valvotomy. The specific problems arising from the combination of the two procedures are discussed. © 1995 Wiley‐Liss, Inc.
Influence of adjunctive balloon angioplasty on coronary blood flow after rotational atherectomy
Authors: Khoury Alexander F. , Bach Richard G. , Kern Morton J.
Published: March 2007

Rotational atherectomy is being performed with increasing frequency in a distinct subset of patients whose lesion characteristics are unfavorable for conventional balloon angioplasty. Although satisfactory luminal enlargement can be accomplished with the use of rotational atherectomy alone in some patients, adjunctive balloon angioplasty is necessary in most patients, to obtain a minimal residual angiographic result. To demonstrate responses associated with rotational atherectomy results, serial coronary blood flow measurements were obtained in a patient undergoing rotational atherectomy for unstable angina. Adjunctive balloon angioplasty resulted in normalization of post‐stenotic coronary flow reserve. Recanalization by rotablator alone may not normalize coronary flow despite a satisfactory angiographic result. © 1995 Wiley‐Liss, Inc.
Coronary air embolism: Incidence, severity, and suggested approaches to treatment
Authors: Khan Miqdad , Schmidt Donald H. , Bajwa Tanvir , Shalev Yoseph
Published: March 2007

Because no well‐controlled study of inadvertent coronary air embolim has been done to truly quantify the incidence of this cardiac catheterization complication, we wanted to determine its incidence and severity in an active teaching medical center and assess approaches to treatment. We retrospectively reviewed 3,715 coronary angiogram and PTCA reports performed over 32 months. Further, we classified severity based on angiographic findings and symptoms as minimal, mild, moderate, and massive. Two independent angiographers reviewed 764 consecutive cines performed in the first 2 months of training of each new fellow and 740 cines performed in the last 2 months of training. We found that during the first 2 months of training the overall incidence for significant intracoronary air embolism was 0.19% (7 documented cases) compared with 0.2% (3 cases) for non‐reported, minimal asymptomatic air embolism. The estimated incidence for total air emboli events was 0.27% (10/3,715). We did not find coronary air emboli in the 740 cines performed at the end of fellowship training. Additionally, the incidence of coronary air emboll during PTCA training was much higher compared with coronary angiography training (0.84 vs. 0.24%). Although there is no best technique to restore blood flow after blockage by air emboli, we suggest as options aspirating the air or forcefully injecting saline, with auxiliary supportive measure like 100% oxygen, IABP, CPR, and DC cardioversion. © 1995 Wiley‐Liss, Inc.
Recanalization of totally occluded saphenous vein grafts using local urokinase delivery with the dispatchTM catheter
Authors: Glazier James J. , Bauer Hans H. , Kiernan Francis J. , Primiano Charles A. , Mitchel Joseph F. , Dougherty James E. , Waters David D. , McKay Raymond G.
Published: March 2007

Current techniques for the percutaneous revascularization of totally occluded vein grafts are limited by a low initial success rate, a significant incidence of distal embolization, and a high rate of early graft reclosure. This case report describes two patients in whom graft recanalization was attempted with the combined use of balloon angioplasty/intra‐graft stent placement and local urokinase delivery using a new angiotherapy catheter. Successful recanalization was achieved in both patients without major complications, in spite of a large thrombus burden as demonstrated by angiography. © 1995 Wiley‐Liss, Inc.
A design example of a 65 nm CMOS operational amplifier
Authors: Schlögl Franz , Zimmermann Horst
Published: March 2007

In this paper, we discuss the properties of new nanometer‐size CMOS technologies being important for the circuit designer. Thereby we concentrate on analogue circuit design. In the literature, the gain reduction by the high output conductance of the transistors is discussed. In detail, we further describe gain reduction due to gate‐leakage current. Finally, we present a design example of a fully differential operational amplifier in a 65 nm CMOS technology including results. Copyright © 2007 John Wiley & Sons, Ltd.
An adaptive multiuser detector for DS‐CDMA systems in multipath fading channels
Authors: Li Min , Hamouda Walaa
Published: March 2007

In this paper, we investigate the performance of an adaptive multistage detection scheme for direct‐sequence code‐division multiple‐access (DS‐CDMA) systems. The first stage consists of an adaptive multiuser detector which is based on the linear constrained minimum variance (LCMV) criterion. The interference cancellation (IC) occurs in the second stage. The performance of the iterative receiver over both flat and frequency‐selective fading channels is investigated and compared to the single‐user bound. In all cases, and under heavy system loads with near‐far problems, the iterative receiver is shown to offer substantial performance improvement and large gain in user‐capacity relative to the standard LCMV. In flat‐fading channels, our results show that the performance of the iterative detector is very close to the single‐user bound. For the frequency‐selective channel, this performance is noted to be in the order of 1 dB far from the single‐user bound. Copyright © 2007 John Wiley & Sons, Ltd.
Maternal and embryonic sources of tyrosine hydroxylase during Drosophila embryogenesis
Authors: Pendleton Robert , Alday Adrian , Paluru Prasuna , Joyner Jeannettee , Jerome Natalie , Hillman Ralph
Published: March 2007

Tyrosine hydroxylase (TH), the enzyme which catalyzes the conversion of tyrosine to L‐DOPA and is rate limiting in catecholamine biosynthesis, is biochemically expressed in late stage wild‐type Drosophila oocytes as well as in early embryogenesis. Null mutant alleles of TH (pale) are embryonic lethals with death occurring in the late embryonic or early larval periods of development. Staging of embryos demonstrated that inhibition of the enzymatic activity of TH by α‐methyl‐p‐tyrosine (αMT) retards the progression of embryos primarily during the organogenesis stages of embryonic development, with lesser effects on earlier and later stages. On the other hand, time of gene action studies with a conditional temperature sensitive pale mutant (plets1) at its restrictive temperature (29°C) indicate an onset of tyrosine hydroxylase gene action beginning in the oocyte stage of development. Thus, maternal as well as embryonic effects on the secretion and/or functionality of this enzyme may play roles in the early developmental program of the organism. genesis 45:152‐155, 2007. © 2007 Wiley‐Liss, Inc.
Characterization of the protein tyrosine phosphatase CD45 on human epidermal Langerhans cells
Authors: Bieber Thomas , Jürgens Maren , Wollenberg Andreas , Sander Erika , Hanau Daniel , de la Salle Henri
Published: March 2007

Human Langerhans cells (LC) express CD45, but clear data about the isoform(s) and their function(s) are lacking. In the present study, double labeling experiments reveal that freshly isolated LC from normal skin are CD45RO+/RA−/RB−. However, after isolation and short‐time culture where LC undergo an in vitro maturation resembling that to lymphoid dendritic cells, CD45RB emerges whereas CD45RO expression decreases. This evolution results from dynamic alternative RNA splicing. Addition of granulocyte‐macrophage colony‐stimulating factor or tumor necrosis factor‐α to short‐time cultures has no significant effect on CD45RB, but both cytokines accelerate the loss of CD45RO. LC isolated from lesional skin of atopic eczema highly express CD45RO and CD45RB. Cross‐linking of CD45 on LC isolated from atopic individuals inhibits the calcium mobilization in response to activation via Fcε receptor type I(FcεRI). Hence, the protein tyrosine phosphatase CD45 from human LC is subjected to a splicing phenomenon related to the differentiation and activation stage of these cells and regulates their FcεRI‐mediated activation.
Critical role of endogenous Mtv in acute lethal graft‐versus‐host disease
Authors: Miconnet Isabelle , Roger Thierry , Seman Michel , Bruley‐Rosset Martine
Published: March 2007

Little is known about the etiology of the graft‐versus‐host disease (GVHD) occuring after transplantation of lymphoid cells incompatible for minor histocompatibility antigens (mHAg). Here, the potential role of host endogenous mouse mammary tumor virus (Mtv)‐encoded superantigens (SAg) in the development of lethal GVHD was investigated. In a combination of H‐2d compatible mice, the presence of Mtv‐7 and, to a lesser extent, of Mtv‐1, ‐6, ‐13 in the host genome, highly increases the rate and severity of GVHD. Kinetic analyses of TCR Vβ gene expression in recipient mice consistently indicate a dramatic but transient infiltration of GVHD target organs by Mtv‐SAg‐specific T cells. This suggests that SAg encoded by endogenous Mtv, by activating large T cell subpopulations, would help the response to mHAg and thus play a critical role in the initiation or aggravation of GVHD.
Immune response to Mycobacterium bovis bacille Calmette Guérin infection in major histocompatibility complex class I‐ and II‐deficient knock‐out mice: contribution of CD4 and CD8 T cells to acquired resistance
Authors: Ladel Christoph H. , Daugelat Sabine , Kaufmann Stefan H. E.
Published: March 2007

Knock‐out mice with defined major histocompatibility complex (MHC) deficiencies were infected intravenously with Mycobacterium bovis bacille Calmette Guérin (M. bovis BCG) to assess the relative impact of MHC class I‐ and II‐dependent immune responses. Heterozygous control mice were capable of controlling growth of M. bovis BCG, although infection progressed chronically, as assessed by determination of colony‐forming units. Furthermore, infected controls developed granulomatous lesions at the site of mycobacterial growth and delayed‐type hypersensitivity (DTH) reactions after challenge with purified protein derivative of tuberculin. In vitro, spleen cells from heterozygous control mice produced high concentrations of interferon‐γ (IFN‐γ) after restimulation with mycobacterial antigens. In contrast, the MHC class II‐deficient Aβ−/− mice, which are virtually devoid of functional CD4 T cells, succumbed to M. bovis BCG infection. Furthermore, Aβ−/− mice lacked DTH reactions to tuberculin and only few minute picnotic lesions were formed in livers of infected mice. Finally, spleen cells from infected Aβ−/− mice failed to produce measurable IFN‐γ concentrations after restimulation in vitro with various mycobacterial antigen preparations. The capacity of β2‐microglobulin (β2m)‐deficient mice, which are devoid of CD8α/β T cells, to inhibit growth of M. bovis BCG was only slightly affected at low inocula, although significantly higher colony‐forming units were detected in spleens. These knock‐out mice developed strong DTH responses to tuberculin and their spleen cells produced high levels of IFN‐γ once reactivated by mycobacterial antigens. Furthermore, in livers of infected β2m‐deficient mice, extravascular infiltrates developed which were more diffuse than those in infected control littermates. Remarkably, the β2m‐deficient mice were substantially more susceptible to higher inocula of M. bovis BCG than their control littermates. Our data formally prove the essential role of MHC class II‐dependent immune mechanisms in all relevant aspects of immunity to M. bovis BCG. In addition, our findings emphasize an important contribution of MHC class I‐dependent immunity to effective anti‐mycobacterial protection. We assume that CD4 T cells are highly effective in containing M. bovis BCG within distinct granulomatous lesions, but fail to eradicate their intracellular pathogens. It appears most likely that CD8 T cells are also required to achieve this goal.
Antigen‐binding B cells and polyreactive antibodies
Authors: Chen Zhi Jian , Wheeler Jim , Notkins Abner Louis
Published: March 2007

The present experiments were initiated to see if cells capable of binding antigens could make polyreactive antibodies. Fluorescein isothiocyanate‐labeled self and non‐self antigens were incubated with B cells from normal individuals. Antigenbinding cells were separated from non‐antigen‐binding cells by flow cytometry, immortalized with Epstein‐Barr virus and analyzed at the clonal level for their capacity to make polyreactive antibodies. Four to six times more cells making polyreactive antibodies were found in the B cell subset that bound antigens than in the B cell subset that did not bind antigens. The majority of the polyreactive antibodies were of the immunoglobulin (Ig)M isotype. Immunoflow cytometry revealed that cell lines making polyreactive antibodies bound a variety of antigens (e.g., insulin, IgGFc and β‐galactosidase), whereas cell lines making monoreactive antibodies bound only a single antigen. The binding of antigens to B cell lines that made polyreactive antibodies could be inhibited (range, 28%–57%) by both homogeneous and heterogeneous antigens. Both CD5+ and CD5− antigen‐binding B cells made polyreactive antibodies, but the frequency was slightly higher in the CD5+ antigen‐binding (85%) as compared to the CD5− antigen‐binding (50%) population. Comparison of CD5+ B cells that bound antigens with CD5+ B cells that did not bind antigens showed that approximately 86% of the former, but only 15% of the latter, made polyreactive antibodies. It is concluded that cells capable of binding a variety of different antigens can make polyreactive antibodies and that antigen binding is a good marker for identifying polyreactive antibody‐producing cells.
Interleukin‐12 is required for interferon‐γ production and lethality in lipopolysaccharide‐induced shock in mice
Authors: Wysocka Maria , Kubin Marek , Vieira Leda Q. , Ozmen Laurence , Garotta Gianni , Scott Phillip , Trinchieri Giorgio
Published: March 2007

Several cytokines, in particular tumor necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ), have been shown to be responsible for pathological reactions which may lead to shock and death observed in infection with Gram‐negative bacteria and in response to endotoxins (lipopolysaccharides, LPS). Priming of mice with the avirulent Bacille Calmette Guérin (BCG) vaccine strain of Mycobacterium bovis increases the sensitivity of mice to the lethal effect of LPS and results in an efficient priming for cytokine production. In response to low doses (1 γg/mouse) of LPS, BCG‐primed mice produce interleukin‐12 (IL‐12) which controls IFN‐γ production, as demonstrated by the ability of neutralizing anti‐IL‐12 antibodies to suppress IFN‐γ production. However, the concentration of the biologically active IL‐12 p70 heterodimer is similar in the serum of both BCG‐primed or unprimed mice, reaching levels of 1–3 ng/ml at 3–6 h after LPS injection, whereas IFN‐γ production was observed only in BCG‐primed mice. The priming effect of BCG on IFN‐γ production appears to be mostly due to its ability to increase TNF‐α production, which acts as cofactor with LPS‐induced IL‐12 in inducing IFN‐γ production, as shown by the ability of injection of TNF‐α and LPS (1 γg/mouse), but not LPS alone, to induce IFN‐γ production. However, in addition to TNF‐α, other LPS‐induced cofactor(s) are required in cooperation with IL‐12 to induce optimal IFN‐γ production, because co‐injection of TNF‐α and IL‐12, sufficient to induce serum concentrations of both cytokines higher and more persistent than those obtained by injection of LPS, was not sufficient to induce IFN‐γ production in vivo. Neutralizing anti‐IL‐12 antibodies, in addition to inhibiting the in vivo LPS‐induced IFN‐γ production, also completely protect BCG‐primed mice injected with up to 10 μg of LPS from shock‐induced death. Thus, IL‐12 is required for IFN‐γ production and lethality in an endotoxic shock model in mice.
Differential expression of type I insulin‐like growth factor receptors in different stages of human T cells
Authors: Kooijman Ron , Scholtens Lies E. , Rijkers Ger T. , Zegers Ben J. M.
Published: March 2007

Insulin‐like growth factor I (IGF‐I) has been implicated to play a regulatory role in T cell development and in T cell function. We investigated the expression of type I IGF receptors on human peripheral T cells related to the maturation and activation stage using the type I IGF receptor‐specific monoclonal antibody αIR3. It appeared that 87% of the CD4+CD45RA+ cells and 66% of the CD8+CD45RA+ cells were αIR3+, whereas only 37% of the CD4+CD45RO+ cells and 38% of the CD8+CD45RO+ cells bound αIR3. We also found that the fraction of αIR3+ cells within in vivo or in vitro activated (HLA‐DR+) T cells is markedly lower than in nonactivated (HLA‐DR−) cells. In vitro phytohemagglutinin‐activated T cells and CD4+CD45RO+ cells activated with recall antigens also contained less αIR3+ cells (1–6%) than nonactivated cells (30–54%).
Measles virus‐induced down‐regulation of CD46 is associated with enhanced sensitivity to complement‐mediated lysis of infected cells
Authors: Schnorr Jens‐Jörg , Dunster Lee M. , Nanan Ralph , Schneider‐Schaulies Jürgen , Schneider‐Schaulies Sibylle , ter Meulen Volker
Published: March 2007

CD46, the major component of the measles virus (MV) receptor complex and a member of the regulators of complement activity (RCA) gene cluster, is down‐regulated in MV‐infected cells. We investigated whether the reduction of surface CD46 correlates with enhanced sensitivity of lymphoid and monocytic cells to lysis by activated complement. On human U937 cells, acutely or persistently infected with MV‐Edmonston (ED) vaccine strain, infection‐dependent down‐regulation of CD46 confers sensitivity to activated complement, regardless of the pathway of activation and the specificity of the activating antibodies. Interestingly, down‐regulation of CD46 alone is sufficient to confer susceptibility of cells to complement lysis despite the continued surface expression of other RCA proteins such as CD35 and CD55. In primary cultures, both peripheral blood lymphocytes and macrophages are efficiently lysed in the presence of complement activated via the alternative pathway after MV infection. In contrast to the MV‐ED infection, infection of cells with the lymphotropic MV wild‐type strain WTF does not down‐regulate CD46. Cells infected with MV‐WTF do not exhibit enhanced susceptibility to complement lysis. These data suggest that MV strains similar to WTF that do not down‐regulate CD46 may have an enhanced potential for replication and dissemination within the human host, whereas complement‐mediated elimination of cells infected with CD46‐down‐regulating strains of MV, such as ED, may limit the spread of MV infection, and could thus represent an attenuating factor for MV.
MEM‐59 monoclonal antibody detects a CD43 epitope involved in lymphocyte activation
Authors: Alvarado Marco , Klassen Claudia , Cerny Jan , Horejí Vaclav , Schmidt Reinhold E.
Published: March 2007

Previous studies on T cell activation via CD43 antigen stimulation were limited to the use of L10, a monoclonal antibody (mAb) recognizing a sialic acid‐independent epitope on the CD43 molecule. Here we study the CD43 mAb MEM‐59, which recognizes a neuraminidase‐sensitive epitope on the CD43 molecule, for its ability to activate T lymphocytes. The antibody by itself is able to stimulate proliferation of peripheral blood mononuclear cells (PBMC) in a monocyte‐dependent fashion, and to act synergistically with the mitogen phorbol 12‐myristate 13‐acetate. It is demonstrated that the monocyte dependence of MEM‐59‐induced proliferation of peripheral blood lymphocytes (PBL) cannot be attributed to cross‐linking via Fc receptors on monocytes alone: F(ab′)2 fragments of MEM‐59 are at least as effective as intact IgG in the induction of PBMC proliferation. The effects of MEM‐59 reported here are distinct in important ways from those reported for L10. Our proliferation data are extended by the observation that MEM‐59 mAb induces mobilization of intracellular Ca2+ in PBMC and in the T cell line Jurkat, while the CD3/TcR‐negative Jurkat derived‐mutant J.TR3‐T3.5 exhibits defective signaling compared to the parent cell line. Moreover, CD3 and CD43 are shown to be present jointly in a large complex in a mild detergent lysate of the T cell line HPB‐ALL. These data indicate a physical and functional association between CD3/TcR and CD43 pathways, suggesting a role for CD43 as a co‐stimulatory molecule in CD3/TcR signaling, especially in T cell‐antigen‐presenting cell interactions.
Antigen presentation by Leishmania mexicana‐infected macrophages: Activation of helper T cells specific for amastigote cysteine proteinases requires intracellular killing of the parasites
Authors: Wolfram Markus , Ilg Thomas , Mottram Jeremy C. , Overath Peter
Published: March 2007

Leishmania mexicana amastigotes proliferate in the phagolysosomes of mammalian macrophages. The parasites abundantly synthesize lysosomal cysteine proteinases, which are encoded by the lmcpb gene family. One of these genes was overexpressed in Escherichia coli, and the purified recombinant protein was used as an antigen to induce and establish a T helper 1 (Th1) cell line. The T cells recognize epitopes shared by the native cysteine proteinases and the recombinant protein. Infected bone marrow‐derived macrophages induced to express major histocompatibility complex class II molecules by interferon (IFN)‐γ do not affect parasite viability. These macrophages fail to stimulate the proliferation of the T cell line. In contrast, strong T cell stimulation is observed after the parasites are killed by treatment with L‐leucine methylester, or after activation of macrophages by IFN‐γ and tumor necrosis factor‐α. It is concluded that infected macrophages efficiently present this lysosomal Leishmania antigen once the parasites are inactivated and degraded. This observation may be of considerable relevance for the outcome of Leishmania infections provided that it can be extended to other parasite antigens.