Tailoring the Weight of Surface and Intralayer Edge States to Control LUMO Energies

The energies of the frontier molecular orbitals determine the optoelectronic properties in organic films, which are crucial for their application, and strongly depend on the morphology and supramolecular structure. The impact of the latter two properties on the electronic energy levels relies primarily on nearest-neighbor interactions, which are difficult to study due to their nanoscale nature and heterogeneity. Here, an automated method is presented for fabricating thin films with a tailored ratio of surface to bulk sites and a controlled extension of domain edges, both of which are used to control nearest-neighbor interactions. This method uses a Langmuir-Schaefer-type rolling transfer of Langmuir layers (rtLL) to minimize flow during the deposition of rigid Langmuir layers composed of π-conjugated molecules. Using UV-vis absorption spectroscopy, atomic force microscopy, and transmission electron microscopy, it is shown that the rtLL method advances the deposition of multi-Langmuir layers and enables the production of films with defined morphology. The variation in nearest-neighbor interactions is thus achieved and the resulting systematically tuned lowest unoccupied molecular orbital (LUMO) energies (determined via square-wave voltammetry) enable the establishment of a model that functionally relates the LUMO energies to a morphological descriptor, allowing for the prediction of the range of accessible LUMO energies.

Multicentre randomised trial of invasive and less invasive surfactant delivery methods showed similar spirometry results at 5-9 years of age

AIM

We explored whether subnormal forced expiratory volume within one second (FEV₁ ) at 5-9 years of age was lower in children born preterm who received less invasive surfactant administration (LISA) rather than surfactant via an endotracheal tube.

METHODS

The multicentre, randomised Nonintubated Surfactant Application trial enrolled 211 preterm infants born at 23-26 weeks of gestation from 13 level III neonatal intensive care units from April 2009 to March 2012. They received surfactant via LISA (n=107) or after conventional endotracheal intubation (n=104). The follow-up assessments were carried out by a single team blinded to the group assignments. The main outcome was FEV₁ <80% of predicted values.

RESULTS

Spirometry was successful in 102/121 children. The other children died or were lost to follow up. Median FEV₁ was 93% (interquartile range 80-113%) of predicted values in the LISA group and 86% (interquartile range 77-102%) in the control group (p=0.685). Rates of FEV₁ < 80% were 11/57 (19%) and 15/45 (33 %) respectively, which was an absolute risk reduction of 14% (95% confidence interval -3.1% to 31.2%, p=0.235). There were no differences in other outcome measures.

CONCLUSION

The proportion of children aged 5-9 years with subnormal FEV₁ was not significantly different between the groups.

Synthesis of block copolymers containing 3-chloro-2-hydroxypropyl methacrylate by NMP – a versatile platform for functionalization

This study highlights the potential of 3-chloro-2-hydroxypropyl methacrylate (ClHPMA) as a functional building block in nanostructured block copolymer architectures.

Polyether-Based Diblock Terpolymer Micelles with Pendant Anthracene Units-Light-Induced Crosslinking and Limitations Regarding Reversibility

The synthesis of 9-methylanthracenyl glycidyl ether (AnthGE) as a crosslinkable monomer that can be applied in anionic ring opening polymerization is reported. Diblock terpolymers of the composition methoxy-poly(ethylene oxide)-block-poly(2-ethylhexyl glycidyl ether-co-9-methylanthracenyl glycidyl ether) (mPEO-b-P(EHGE-co-AnthGE) with 10 to 24 wt% of AnthGE are synthesized and characterized. Their micellization behavior, as well as their light-induced core-crosslinking via irradiation with UV light (λ = 365 nm) is studied. The results are compared with studies on the dimerization, and the dimer cleavage via irradiation with UV-C light (λ = 254 nm), of the same diblock terpolymer in organic solution, and the small-molecule model compound 9-methoxymethylanthracene. Differences in ¹ H NMR spectra of the crosslinked or dimerized compounds and reaction kinetics of the dimerization reactions under different conditions suggest possible side reactions for the case of the core-crosslinking of micelles in aqueous solution. These side reactions limit the reversibility of the anthracene dimerization reaction in aqueous solutions, even if the anthracene molecule is encapsulated within the hydrophobic core of a polymeric micelle.

Polymer Micelles Composed of Molecular-Bottlebrush-Based Surfactants: Precisely Controlling Aggregation Number Corresponding to Polyhedral Structures

Over the past few decades, there has been remarkable progress in the construction of self-assemblies in the field of supramolecular chemistry, such as micelles with precisely controlled and refined structures. One promising approach represents the previously proposed concept of Platonic micelles, in which the aggregation number (N_agg ) is discretized in accordance with vertexes of regular polyhedra (i.e., Platonic solids), i.e., 4, 6, 8, 12, and 20 units. Herein, attempt is made to construct Platonic polymer micelles using rigid and persistent architecture of molecular-bottlebrush-based surfactant (MBS). The structure of MBS micelles is carefully elucidated using small-angle X-ray and light scattering and analytical centrifugation measurements. This study shows that the N_agg of MBS micelles is consistent with one of the Platonic numbers when N_agg is intentionally set in the range of 4-20. In addition, some of the MBS micelles demonstrate a discontinuous change in N_agg , when the salt concentration is changed, which is an important factor in controlling micellar N_agg . This is one of the characteristic aggregation behaviors of Platonic micelles in surfactant systems, which strongly indicates the formation of Platonic micelles from macromolecular surfactants.

Core-Cross-linked Fluorescent Worm-Like Micelles for Glucose-Mediated Drug Delivery

We herein report the fabrication of core-crosslinked, fluorescent, and surface-functionalized worm-like block copolymer micelles as drug delivery vehicles. The polyether-based diblock terpolymer [allyl-poly(ethylene oxide)-block-poly(2-ethylhexyl glycidyl ether-co-furfuryl glycidyl ether)] was synthesized via anionic ring opening polymerization, and self-assembly in water as a selective solvent led to the formation of long filomicelles. Subsequent cross-linking was realized using hydrophobic bismaleimides as well as a designed fluorescent cross-linker for thermally induced Diels-Alder reactions with the furfuryl units incorporated in the hydrophobic block of the diblock terpolymer. As a fluorescent cross-linker, we synthesized and incorporated a cyanine 5-based bismaleimide in the cross-linking process, which can be used for fluorescence tracking of the particles. Furthermore, we covalently attached glucose to the allyl end groups present on the surface of the micelles to investigate active glucose-mediated transport into suitable cell lines. First studies in 2D as well as 3D cell culture models suggest a glucose-dependent uptake of the particles into cells despite their unusually large size compared to other nanoparticle systems used in drug delivery.

Amine-containing diblock terpolymers via AROP: a versatile method for the generation of multifunctional micelles

We herein report the synthesis and block copolymerization via AROP of three glycidyl amine species (PiGA; OPGA, and MPGA) with different hydrophobicity. Micelles formed from these block copolymers respond to changes in pH and H₂O₂ concentration.

Triple-Responsive Polyampholytic Graft Copolymers as Smart Sensors with Varying Output

Three triggers result in two measurable outputs from polymeric sensors: multiresponsive polyampholytic graft copolymers respond to pH-value and temperature, as well as the type and concentration of metal cations and therefore, allow the transformation of external triggers into simply measurable outputs (cloud point temperature (T_CP ) and surface plasmon resonance (SPR) of encapsulated silver nanoparticles). The synthesis relies on poly(dehydroalanine) (PDha) as the reactive backbone and gives straightforward access to materials with tunable composition and output. In particular, a rather high sensitivity toward the presence of Cu²⁺ , Co²⁺ , and Pb²⁺ metal cations is found.

[Lung and pleural lesions before and after implementation of a national eradication program against enzootic pneumonia and actinobacillosis as well as changes of slaughter carcass organs in slaughter pigs in Switzerland]

In a representative cross-sectional study during 12 months of the years 2008/2009 in four abattoirs in Switzerland, lung and pleura lesions as well as lesions of slaughter carcasses and organs of 34 706 pigs were studied for frequency and type of macroscopic lesions. Of the 24276 examined pigs, 91.2% of the lungs, 94.4% of the heart and 95.5% of the livers showed no macroscopically visible lesions. Pigs that were produced for a label program had significantly less bronchopneumonia and pneumonia residuals, pleuritis and liver lesions due to echinococcosis. Pigs supervised by the Swiss Pig Health Service (SGD), showed significantly less bronchopneumonia and pneumonia residuals, diffuse pleuritis, pleuritis/pericarditis and milkspots compared to the non-SGD supervised farms. Thanks to the national eradication program for enzootic pneumonia (EP) and actinobacillosis, the health-status of lungs has been considerably improved and the prevalence of pleurisy decreased considerably. The results of this study indicate a good herd health in Swiss pig production.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

[Consensus recommendations of the German Radiology Society (DRG), the German Cardiac Society (DGK) and the German Society for Pediatric Cardiology (DGPK) on the use of cardiac imaging with computed tomography and magnetic resonance imaging]

Cardiac magnetic resonance imaging (MRI) and computed tomography (CT) have been developed rapidly in the last decade. Technical improvements and broad availability of modern CT and MRI scanners have led to an increasing and regular use of both diagnostic methods in clinical routine. Therefore, this German consensus document has been developed in collaboration by the German Cardiac Society, German Radiology Society, and the German Society for Pediatric Cardiology. It is not oriented on modalities and methods, but rather on disease entities. This consensus document deals with coronary artery disease, cardiomyopathies, arrhythmias, valvular diseases, pericardial diseases and structural changes, as well as with congenital heart defects. For different clinical scenarios both imaging modalities CT and MRI are compared and evaluated in the specific context.

Four-dimensional visualization of thoracic blood flow by magnetic resonance imaging in a patient following correction of transposition of the great arteries (d-TGA) and uncorrected aortic coarctation

Recent advances in flow-sensitive magnetic resonance imaging (MRI) and data analysis allow for comprehensive noninvasive three-dimensional (3D) visualization of complex blood flow. Electrocardiogram (ECG)-gated three-directional (3dir) flow measurements were employed to assess and visualize time-resolved 3D blood flow in the pulmonary arteries (PA) and thoracic aorta. We present findings in a juvenile patient with surgically corrected transposition of the great arteries (d-TGA) and aortic coarctation. For the first time, the complex flow patterns in the PA following d-TGA were visualized. Morphologically, a slight asymmetry of the PA was found, with considerable impact on vascular hemodynamics, resulting in diastolic retrograde flow in the larger vessel and diastolic filling of the smaller PA. Additionally, increased flow to the supraaortic vessels was found due to aortic coarctation.

Surgical Treatment of Long-Segment Tracheal Anomalies in Infants and Children

BACKGROUND

Tracheal stenosis in combination with vascular and/or cardiac anomalies is a life-threatening condition in infants and children presenting with severe symptoms of airway obstruction. The optimal surgical treatment of these cases remains controversial.

OBJECTIVES

We present here a group of infants and children with combined tracheal malformations and vascular and/or cardiac anomalies. More than 30 % of the stenotic trachea was resected in a subgroup of the patients. A reconstruction with end-to-end anastomosis was achieved on the basis of extensive mobilization of the whole tracheobronchial tree and use of CPB.

METHODS

The clinical outcome in 37 children with a median age of 8 (1 - 72) months was analyzed retrospectively. The patients presented with severe airway obstruction in combination with congenital heart defects and/or vascular anomalies. Cardiac catheterization, bronchoscopy and thoracic computer tomography were performed prior to operation. The operations were performed under CPB and consisted of tracheal resection with end-to-end anastomosis or external stabilization. Associated intracardiac and vascular anomalies were repaired simultaneously.

RESULTS

All but 1 patient survived and had a straightforward recovery. The patients were extubated under bronchoscopic control with a median intubation time after airway repair of 12.2 days. The average follow-up was 8.4 years (1 - 14 years) and the surviving patients did not show signs of restenosis clinically. A segment longer than 30 % of the tracheal length was resected and reconstructed with end-to-end anastomosis in 57 % of the patients (12 of 21 patients).

CONCLUSIONS

Our experience demonstrates that resection of tracheal stenosis and end-to-end anastomosis can be achieved successfully even in cases with stenosis of more than 30 % of the total tracheal length. The use of CBP allowed extensive mobilization of the tracheobronchial tree and resection with end-to-end tension-free anastomotic reconstruction.

Das transitionalzellige Ovarialkarzinom

Transitional cell carcinoma of the ovary (TCC-O) is a less common type of malignant surface epithelial-stromal tumor of the ovary, still with uncertain incidence. Histologically, TCC-O resembles urothelial carcinoma of the urinary system, and by definition does not contain a Brenner tumor component. TCC-O may not be a bona fide urothelial neoplasm, however, but rather a lesion of the Müllerian type derived from the ovarian surface epithelium. This notion is supported by the existence of mixed tumors consisting of TCC-O and other histological types of ovarian carcinoma, as well as the observation that TCC-O has a Müllerian type but not a urothelial-like immunohistochemical profile. Besides metastatic urothelial carcinoma of the urinary tract, the other types of ovarian carcinoma, as well as sex cord-stromal tumors such as adult granulosa cell tumors, have to be considered in the differential diagnosis of TCC-O. A recent analysis of a large series of advanced ovarian carcinomas treated by radical surgery and postoperative chemotherapy confirms studies that had suggested that TCC-O has a better prognosis (with current treatment) than that of the other histological types of ovarian carcinoma. Further studies applying standardized histopathological criteria are needed to clarify the true incidence and behavior of TCC-O. In addition, it is important to study the biological and molecular background of this apparently less aggressive phenotype.

On the use of an ontology for the identification of degrees of freedom in urban wastewater systems

The management of Urban Wastewater Systems (UWS) requires a comprehensive understanding of the interactions of processes and substances in the system. This leads to complex numerical models which can be applied to predict management actions or understand misconduction of the system. Nevertheless, for the communication between stakeholders in the process of optimizing a UWS these models are far too sophisticated. In this paper the use of an ontology is described serving as a conceptual model of the UWS which can be used for dissemination or as a preliminary stage to numerical models. The ontology therefore is part of a dissemination tool describing potential measures which can be applied to optimize a UWS.

[Five hundred outpatient hernioplasties using the Lichtenstein method]

The Lichtenstein repair method is an excellent and simple technique for hernia repair performed as a day-case procedure. A consecutive series of 500 ambulatory groin hernia repairs from 1994 to 2002 was studied. The mean follow-up for 84.6% of the patients was 2 years (range 6-86 months). There were no severe complications. The rate of clinically important wound haematomas (n=6, 1.2%) was low, as well as the numbers of testicular atrophies (n=1, 0.2%) and deep wound infection (n=1, 0.2%). We saw no thrombosis. There were 15 recurrences (3.5%). Ninety-six per cent of the patients were satisfied with the outpatient operation. In day-case surgery, conditions for the patients' treatment at home should be checked carefully by surgeons before the operation.

CONCLUSION

Our results suggest that the number of day-case hernia repairs can be increased without severe complications. The procedure can be performed on an outpatient basis without problems under general anaesthesia. Increasing day-case surgery could significantly reduce the costs of health care.

Rings, slings and other vascular abnormalities

Ultrafast CT and MR angiography are noninvasive, accurate and robust techniques for preoperative diagnosis and planning of congenital heart disease and vascular abnormalities in pediatric patients. While they seem to be equivalent to conventional catheter angiocardiography for detecting vascular abnormalities, they are more accurate for the diagnosis of potentially life-threatening complications, such as tracheal, bronchial or esophageal compression. The value of ultrafast CT and MR angiography is demonstrated in 22 pediatric patients with vascular rings, slings and other vascular abnormalities.

[Time-resolved multiphasic 3D MR angiography in the diagnosis of the pulmonary vascular system in children]

PURPOSE

To evaluate time-resolved, multiphasic 3D MR angiography (MRA) for the non-invasive assessment of the pulmonary vascular system in children.

MATERIALS AND METHODS

10 children aged 6 to 15 years (mean age 10 years) ware examined on a 1.5 T whole body MR system with time-resolved, multiphasic 3D MRA after injection of 0.2 mmol/kg body weight of Gd-DTPA. With the use of an ultrafast gradient echo pulse sequence with asymmetric k-space filling and very short echo and repetition times, a nominal spatial resolution of 1.4 x 1.4 x 2.0 mm3 could be achieved with a scan time of 5.6 and 6.2 seconds for a single 3D data set. Two radiologists, who were blinded to the clinical diagnosis, analyzed the image data in consensus. The image analysis included the assessment of the image contrast and artifacts as well as a quantitative analysis of the signal-to-noise (SNR) and contrast-to-noise ratios (CNR) for central and peripheral lung vessel segments.

RESULTS

The children tolerated all examinations without any side effects. The referral diagnosis, which was based on echocardiography, catheter angiography and surgery, was confirmed by MRA in all cases. The image contrast was rated at least satisfactory in all but one case (19 of 20) and no artifacts were observed. The quantitative analysis of the SNR and CNR in the pulmonary arteries and veins confirmed the reader analysis of a high and uniform contrast throughout the entire pulmonary circulation.

CONCLUSION

Time-resolved multiphasic 3D MRA allows a non-invasive diagnostic evaluation of the pulmonary circulation in children. In view of the excellent image quality, MRA may replace conventional diagnostic catheter angiography in the near future.

Assessments of impacts of nitrogen deposition on beech forests: results from the Pan-European Monitoring Programme

The article reviews effects of nitrogen (N) deposition on beech forest ecosystems in Europe. On the basis of beech plots of the Pan-European Monitoring Programme of ICP Forests and the EU, the deposition of N compounds as well as input-output budgets are listed and compared with studies in North America. The authors also discuss the critical threshold for N leaching. At present, N is leached in 10% of the plots evaluated. An in-depth evaluation of a beech plot in central Germany is presented. The high N leaching results in a considerable increase (four times higher N content in 2000 compared to 1965) in the export of nitrate from the beech forests from a nearby source. Finally, ecophysiological indicators (N content in beech leaves, fine root system, N content, root/shoot ratios) are discussed as a result of high N input.

Exploratory analysis and a stochastic model for humusdisintegration

Ulrich (1981) supposes in the hypothesis of humusdisintegration that the balance between polymerisation and breakdown of organic material may be disturbed in chemically well buffered European forest soils. This new aspect of aluminium toxicity may cause nitrogen exceedance in forest ecosystems and subsequent seasonal nitrate output (Eichhorn and Hutterman, 1999). In a research program the substances in the seepage water are monitored in a small woodland in central Germany. We explore these multivariate data for examining possible influences on the process of humusdisintegration and its temporal evolution. As a result, a regression model for carbon is developed, which includes covariables, i.e., other substances, as well as spatial and temporal terms describing systematic variability. Especially iron and aluminium turn out to be very influential in the model. So far our work is a basic step for monitoring the seepage water data by means of stochastic modelling.

Insulin activates phospholipase C-gamma1 via a PI-3 kinase dependent mechanism in 3T3-L1 adipocytes

Previously we have shown that the insulin receptor and phospholipase C-gamma1 physically interact in the 3T3-L1 adipocyte cell line. In this study, we investigated the ability of insulin and PDGF to stimulate PLC-gamma1 enzyme activity as measured by PI-(4,5)P(2) hydrolysis. Both insulin and PDGF caused a rapid (<1 min) increase in PLC activity associated with the respective receptor. PDGF treatment resulted in a higher and more sustained stimulation of PLC-gamma1 activity compared to insulin (0.95 pmol/min/mg vs 0.68 pmol/min/mg). Furthermore, insulin and PDGF promoted increases in total cellular DAG, one of the products of PI-(4,5)P(2) hydrolysis. Insulin-stimulated PLC activity appears to be downstream of PI-3Kinase as the DAG increase was partially blocked by Wortmannin and addition of PI-(3,4,5)P(3) activated PLC-gamma1 in vitro. Inhibition of PLC using U73122 or an inhibitory peptide caused a decrease in insulin-stimulated 2-deoxyglucose transport and GLUT4 translocation that was rescued by the addition of OAG, a cell-permeable synthetic DAG.

Inhibition of PLC-gamma1 activity converts nerve growth factor from an anti-mitogenic to a mitogenic signal in CHO cells

Nerve growth factor (NGF) treatment of Chinese hamster ovary fibroblast (CHO) cells exogenously expressing 2.5x105 TrkA receptors (CHO/TrkA) results in inhibition of serum and insulin-like growth factor-I (IGF-I) stimulated cell proliferation in a dose-dependent manner. Furthermore, NGF does not stimulate [3H]thymidine incorporation and inhibits IGF-I mediated DNA synthesis in CHO/TrkA cells. NGF and IGF-I induce extracellular-signal regulated kinase 1 (ERK1) and ERK2 activation, but NGF is able to stimulate a higher and more sustained activation of these enzymes compared with IGF-I. Cotreatment with NGF and IGF-I yields an ERK1/2 activity profile similar to that of NGF treatment alone. While pretreatment with mitogen activated protein kinase kinase (MKK) inhibitor PD98059 (30 microM) results in 100% inhibition of IGF-I stimulated MAPK phosphorylation (IC50<1 microM), NGF mediated MAPK phosphorylation is only decreased by 50% (IC50=3 microM). NGF, but not IGF-I, stimulates tyrosine phosphorylation and activation of PLC-gamma1 which can be inhibited in a dose-dependent manner by phosphoinositide-specific phospholipase C (PI-PLC) inhibitor U73122 (IC50=4 microM). Pretreatment with U73122 (IC50=7 microM) results in an 87% inhibition of NGF mediated MAPK phosphorylation, while cotreatment with PD98059 and U73122 results in 97% inhibition. U73122 pretreatment has no effect on NGF stimulated Akt activation. NGF, but not IGF-I, stimulates the tyrosine phosphorylation of Suc1-associated neurotrophic factor-induced tyrosine phosphorylation target (SNT-1)/fibroblast growth factor receptor substrate 2 (FRS2) which can be completely prevented by pretreatment with 10 microM U73122. Finally, inhibition of PI-PLC results in NGF's ability to stimulate DNA synthesis in the absence and presence of IGF-I.

Association of the insulin receptor with phospholipase C-gamma (PLCgamma) in 3T3-L1 adipocytes suggests a role for PLCgamma in metabolic signaling by insulin

Phospholipase C-gamma (PLCgamma) is the isozyme of PLC phosphorylated by multiple tyrosine kinases including epidermal growth factor, platelet-derived growth factor, nerve growth factor receptors, and nonreceptor tyrosine kinases. In this paper, we present evidence for the association of the insulin receptor (IR) with PLCgamma. Precipitation of the IR with glutathione S-transferase fusion proteins derived from PLCgamma and coimmunoprecipitation of the IR and PLCgamma were observed in 3T3-L1 adipocytes. To determine the functional significance of the interaction of PLCgamma and the IR, we used a specific inhibitor of PLC, U73122, or microinjection of SH2 domain glutathione S-transferase fusion proteins derived from PLCgamma to block insulin-stimulated GLUT4 translocation. We demonstrate inhibition of 2-deoxyglucose uptake in isolated primary rat adipocytes and 3T3-L1 adipocytes pretreated with U73122. Antilipolytic effect of insulin in 3T3-L1 adipocytes is unaffected by U73122. U73122 selectively inhibits mitogen-activated protein kinase, leaving the Akt and p70 S6 kinase pathways unperturbed. We conclude that PLCgamma is an active participant in metabolic and perhaps mitogenic signaling by the insulin receptor in 3T3-L1 adipocytes.

Noninvasive biomagnetic imaging in coronary artery disease based on individual current density maps of the heart

OBJECTIVE

In this paper we present an attempt at noninvasive imaging of distributed myocardial electrical activity in patients suffering from myocardial infarction and in healthy subjects. Although advances have been made, noninvasive three-dimensional imaging of cardiac electrophysiological activity is still in its infancy and extending our knowledge of cardiac electrophysiological properties may be a valuable guide in the treatment of patients with coronary artery disease.

METHODS

Magnetic field mapping data formed the input for an inverse solution that is based on a multiple dipole model. The lead field normalized minimum norm least square criterion was applied to predefined myocardial source geometry. Current density distributions were calculated for the left ventricle during ventricular depolarization. Images from two patients with previous myocardial infarction were compared to images from two healthy subjects.

RESULTS

Low regional and global current density was found in the infarction patients. Regions of low current density corresponded to infarcted segments. The images of the healthy subjects displayed less marked areas of low current density.

CONCLUSION

The proposed multiple dipole model may be able to distinguish viable from scarred myocardium. A prospective clinical study should be undertaken to investigate the spatial resolution and the diagnostic performance of this method.

Antiendothelial cell antibodies in thromboangiitis obliterans

The occurrence of autoimmune phenomena in 28 patients with thromboangiitis obliterans (Buerger's disease) was determined. The following were sought: antineutrophil cytoplasmic antibodies against proteinase 3 (cANCA) and myeloperoxidase (pANCA), antinuclear antibodies, anti-Ro antibodies, anticardiolipin antibodies, and antiendothelial cell antibodies (AECA). For the last, an enzyme-linked immunosorbent assay was developed which verified the presence of the AECA phenomenon with immunofluorescence and confocal microscopy. Seven patients with active disease had AECA titers of 1,857 +/- 450 arbitrary units (AU) compared with 126 +/- 15 AU in 30 normal control subjects (P < 0.001) and 461 +/- 41 AU in 21 patients in remission (P < 0.01). Antibodies from the sera of patients with active disease reacted not only with surface epitopes but also with sites within the cytoplasm of human endothelial cells. AECA may be useful in following disease activity and may play a role in the pathogenesis of thromboangiitis obliterans.

Endothelial adhesion molecules and leukocyte integrins in preeclamptic patients

Endothelial cell activation is important in the pathogenesis of preeclampsia; however, the nature of the activation is unknown. We investigated 22 patients with preeclampsia. 29 normotensive pregnancies, and 18 nonpregnant women to test the hypothesis that serum from preeclamptic patients induces expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) and stimulates intracellular free calcium concentrations [Ca2+]i in cultured endothelial cells. We then asked whether the corresponding integrin adhesive counter receptors lymphocyte function-associated antigen-1 (CD11a/CD18), macrophage-1 antigen (CD11b/CD18), p150,95 (CD11c/CD18), and very late activation antigen-4 (CD49/CD29) are increased in patients with preeclampsia. In the pregnant women, the measurements were conducted both before and after delivery. Integrin expression was measured by fluorescent antibody cell sorting analysis using monoclonal antibodies. ICAM-1 and VCAM-1 were analyzed on endothelial cells by enzyme-linked immunosorbent assay. [Ca2+]i was measured with fura 2. Serum from preeclamptic patients increased endothelial cell ICAM-1 expression but not VCAM-1 expression. Preeclamptic patients' serum also increased [Ca2+]i in endothelial cells compared with serum from normal nonpregnant or normal pregnant women. Endothelial cell [Ca2+]i concentrations were correlated with the ICAM-1 expression in preeclamptic patients (r = .80, P < .001) before but not after delivery. Expression of the integrin counter receptors on leukocytes was similarly increased in preclampsia and normal pregnancy compared with the nonpregnant state. The expression decreased significantly after delivery in both groups. Our results demonstrate that serum from preeclamptic women induces increased ICAM-1 surface expression on endothelial cells, while the expression of the integrin counterreceptors was not different. The effect on endothelial cells may be related to an increase in [Ca2+]i. The effect on cultured endothelial cells and the rapid decrease after delivery suggests the presence of a circulating serum factor which increases endothelial cell [Ca2+]i and enhances adhesion molecule expression.

Anti-endothelial cell antibodies in Takayasu arteritis

BACKGROUND

Although a specific etiology for Takayasu arteritis has not been found, the bulk of evidence favors an autoimmune mechanism. We examined the sera of 19 patients with Takayasu arteritis for antineutrophil cytoplasmic antibodies (ANCA), antinuclear antibodies (ANA), anti-DNA antibodies, antibodies to extractable nuclear antigens (ENA), anti-Ro anti-bodies, anticardiolipin antibodies, circulating immune complexes, and anti-endothelial cell antibodies (AECA).

METHODS AND RESULTS

We used enzyme-linked immunoassays, immunofluorescence, counterimmunoelectrophoresis, fluorescent-activated cell sorter (FACS) analysis, and confocal microscopy. We found that although no patient had positive ANCA, ANA, anti-DNA antibodies, ENA antibodies, anti-Ro antibodies, or anticardiolipin antibodies, 18 of the 19 patients had AECA. The AECA titers of the patients were 2561 +/- 1458 compared with 126 +/- 15 arbitrary units in a normal group of control subjects (P < .001). To verify the specificity of AECA, we performed cytofluorimetry on human endothelial cells with the sera from patients and control subjects. Two entirely separate patterns of fluorescence intensity were identified. We next performed immunocytochemistry and confocal microscopy with human endothelial cells subjected to patients' sera and to sera from normal subjects. The cells subjected to sera from patients with Takayasu arteritis demonstrated specific immunofluorescent staining of their plasma membrane and cytosol.

CONCLUSIONS

AECA are frequently present in patients with Takayasu arteritis. They may play a role in the pathogenesis. Furthermore, they may be useful as an additional diagnostic tool.