julilili42/papers huggingface dataset:
ETA receptor blockade improves post-ischaemic functional recovery in ‘hibernating’ rat myocardium
2002-09-01

Endothelin-1 (ET-1) is a potent vasoconstrictor, and ETA receptors mainly mediate this effect. Elevated plasma levels of ET-1 are observed in patients with coronary heart disease. The release of this peptide from the damaged endothelium may play a role in the initiation and maintenance of myocardial ischaemia. This study examines the ETA receptor-mediated role of endogenous ET-1 in post-ischaemic myocardial function after prolonged hypoperfusion in normal non-failing hearts. In an isolated rat heart model for short-term myocardial hibernation, left ventricular functional recovery after 3h of hypoperfusion (15% of pre-ischaemic flow) followed by 2h of reperfusion was determined. Under steady-state conditions, coronary flow, left ventricular pressure (LVP) and dP/dtmax were measured in the isovolumically beating heart. Additionally, the maximal inotropic response (LVP and dP/dtmax) to calcium stimulation was determined. To study the role of ETA receptors under these pathophysiological conditions, one group was treated with the ETA antagonist BQ 610 (0.8μmol/l) during hypoperfusion, and compared with a control group which received a saline infusion during hypoperfusion. Reperfusion for 2h after 3h of hypoperfusion resulted in partial functional recovery in both groups. Post-ischaemic recovery was significantly better in the hearts that were treated with the ETA antagonist BQ 610 during hypoperfusion (LVP, +19.5% compared with control; dP/dtmax, +13.7% compared with control). The inotropic response to calcium was nearly normalized after ETA blockade. Thus the normal non-failing myocardium profits from ETA receptor blockade during a prolonged period of hypoperfusion, resulting in significantly better post-ischaemic recovery of myocardial function.
Transdermal application of prostaglandin E1 ethyl ester for the treatment of trophic acral skin lesions in a patient with systemic scleroderma
2002-09-01

Abstract An early clinical symptom in scleroderma patients is Raynaud's phenomenon. Later cutaneous manifestations of the disease include oedematous swelling in the extremities and in more extreme cases often very painful, refractory acral necroses. We report on a 56‐year‐old female patient who participated in a prospective, double‐blind, multicentre comparative pilot study because of her severe Raynaud symptoms, with dystrophic skin lesions on both hands. The goal of the study was to evaluate the efficacy and safety of prostaglandin E 1 ethyl ester in a transdermal drug delivery system compared with placebo in patients with secondary Raynaud's phenomenon associated with systemic scleroderma or mixed connective tissue disease. After 2 weeks of verum treatment the patient experienced a marked improvement of Raynaud's attacks, with increased capillary flow velocity, reduced blood stasis and clinical healing of the acral trophic lesions. For this patient the transdermal application of prostaglandin E 1 ethyl ester in the form of a medicated patch proved to be a simple and effective therapy for the acral trophic skin lesions associated with systemic scleroderma.
Chronic elevated endothelin-1 concentrations regulate mitogen-activated protein kinases ERK 1 and ERK 2 in vascular smooth muscle cells
2002-09-01

Increased endothelin-1 (ET-1) levels are found in patients with atherosclerosis. ET-1 is known to increase the mitotic response of different growth factors already at threshold concentrations. The aim of this study was to investigate the influence of ET-1 on the mitogen-activated protein (MAP) kinases, extracellular signal-regulated protein kinase (ERK) 1 and ERK 2. Smooth muscle cells were incubated with ET-1 at a concentration of 10-7M for 1–120h. ERK 1 and ERK 2 were determined in cell homogenates by electrophoresis. Specific antibodies were used to investigate the amount of ERK 1 or ERK 2 in the homogenate. The functional activity of ERK 1 and ERK 2 was determined. Immunofluorescence microscopy was performed to analyse the translocation of the MAP kinases into the nucleus. ET-1 incubation for 12h decreased ERK 1 concentration by -51%. After 36h of ET-1 application the concentration of ERK 1 increased to control levels again. When the cells were incubated for 120h ERK 1 rose by +65% above control. The incubation with ET-1 in the presence of an ETA receptor antagonist inhibited the increase of ERK 1. ERK 2 showed a comparable time course with an initial decrease in the protein concentration followed by an increase after 120h. Incubation with an ETA receptor antagonist inhibited the increase in protein concentration after 120h. However, the functional activity of both MAP kinases remained unchanged between 1 and 120h. Especially, after 120h of ET-1 incubation no translocation into the nucleus was observed. However, an additional stimulus with angiotensin II resulted in translocation of ERK into the nucleus. These data show that ET-1 increases the protein concentration of MAP kinases ERK 1 and ERK 2 but not their basal activity. Only an additional stimulation with angiotensin II leads to the translocation of ERK into the cell nucleus.
Fremde (the Foreign, Strange, Other) and the Museum
2002-09-01

The museum as an institution has had a historically incomparable career in Europe (and elsewhere), a fact this article attempts to explain. Its basic assumption is that the success of the museum does not rest on a promise of experiences of familiarity, on the contrary, its success is due to the increase in experiences of alterity in modern society. The museum is intrinsically a place of foreignness: the objects are delocated, they originate from a foreign place (in the geographic and/or historical sense), and they are (didactically) presented in contexts that “estrange” them. As a place of “heterodoxy” (in Baudrillard's sense of the term), the museum has been described by the German philosopher Peter Sloterdijk as a “xenological institution,” meaning that it encourages an “intelligent border traffic with foreignness” by presenting, framing, and explaining the Other. In this sense, the museum is an institution which responds to specific needs of modern society.
An Axially Bridged Indium Phthalocyanine Dimer with an In���In Bond
2002-09-02

Enhanced nonlinear optical response is observed in a soluble dimeric indium–phthalocyanine (Pc) complex stabilized as a Lewis base adduct. The Pc moieties are tilted 14.5° from an axis connecting the In centers, which are out of plane with respect to the Pc macrocycles (see diagram). The InIn separation was calculated to be 3.24 Å by using extended X-ray absorption fine structure (EXAFS) spectroscopy.
An Axially Bridged Indium Phthalocyanine Dimer with an In���In Bond
2002-09-02

Verstärkte nichtlineare optische Eigenschaften werden bei einem löslichen dimeren Indium-Phthalocyanin(Pc)-Komplex beobachtet, der als Lewis-Base-Addukt stabilisiert wird. Die In-Zentren liegen etwas außerhalb der makrocyclischen Ringebenen, und die Pc-Liganden sind bezüglich der In-In-Achse um 14.5° gekippt (siehe Bild). Der In-In-Abstand wurde durch EXAFS-spektroskopische Messungen zu 3.24 Å bestimmt.
Comparing brain activation associated with isolated upper and lower limb movement across corresponding joints
2002-09-04

Abstract It was shown recently that functional activation across brain motor areas during locomotion and foot movements are similar but differ substantially from activation related to upper extremity movement (Miyai [ 2001 ]: Neuroimage 14:1186–1192). The activation pattern may be a function of the behavioral context of the movement rather than of its mechanical properties. We compare motor system activation patterns associated with isolated single‐joint movement of corresponding joints in arm and leg carried out in equal frequency and range. Eleven healthy volunteers underwent BOLD‐weighted fMRI while performing repetitive elbow or knee extension/flexion. To relate elbow and knee activation to the well‐described patterns of finger movement, serial finger‐to‐thumb opposition was assessed in addition. After identifying task‐related voxels using statistical parametric mapping, activation was measured in five regions of interest (ROI; primary motor [M1] and somatosensory cortex [S1], premotor cortex, supplementary motor area [SMA] divided into preSMA and SMA‐proper, and cerebellum). Differences in the degree of activation across ROIs were found between elbow and knee movement. SMA‐proper activation was prominent for knee, but almost absent for elbow movement ( P &lt; 0.05); finger movement produced small but constant SMA‐proper activation. Ipsilateral M1 activation was detected during knee and finger movement, but was absent for the elbow task ( P &lt; 0.05). Knee movement showed less lateralization in M1 and S1 than other tasks ( P &lt; 0.05). The data demonstrate that central motor structures contribute differently to isolated elbow and knee movement. Activation during knee movement shows similarities to gait‐related activation patterns. Hum. Brain Mapping 17:131–140, 2002. © 2002 Wiley‐Liss, Inc.
Adsorption/desorption phenomena on pure and Teflon® AF‐coated titania surfaces studied by dynamic contact angle analysis
2002-09-05

Abstract As a result of inflammatory processes, plaque formation on dental titanium implants often leads to clinically pathogenic situations. This special biofilm formation on (bio)materials in contact with saliva is initiated by ionic and protein interactions. In this interfacial process, albumin becomes a main constituent of dental pellicle. Interfacial reactions change the surface characteristics. They determine the following steps of macromolecular adsorption and bacterial adhesion. This work focuses on the dynamic contact angle analysis (DCA), which is a tool for online measurements of dynamic changes of wettability without disturbing the interface during detection. Repeatability of the DCA method has been assessed according to the Bland and Altman method. The kinetics and equilibrium data of shifts in the wetting tension hysteresis indicate ionic influences at the titanium/bovine serum albumin (BSA) interface: the Ca‐mediated increase of the BSA adsorption on titanium and the adsorption maximum at the isoelectric point (IEP) of BSA. Ti was surface modified by Teflon® AF polymeric coatings. The result of the assessment gives reason to consider Teflon® AF as a reference material for DCA repeatability studies. This surface modification caused drastic changes in the dynamic interfacial reactions. Shifts in the wetting tensions during DCA adsorption‐desorption experiments clearly demonstrated the partially irreversible adsorption of BSA on Teflon® AF. In contrast, reversible adsorption behavior was detected on pure Ti surfaces. These findings strengthen the hypothesis that the analysis of dynamic changes in wetting tension and wetting tension hysteresis is a sensitive analytical method for the detection of dynamic interfacial changes at biomaterial/biosystem interfaces during the initial steps of biofilm formation. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 567–578, 2002
Critical role of nuclear factor‐κB and stress‐activated protein kinases in steroid unresponsiveness
2002-09-05

Glucocorticoid resistance is a serious clinical problem in chronic inflammatory diseases, because many patients with rheumatoid arthritis, asthma, or Crohn's disease fail to respond to steroid treatment. The molecular mechanisms underlying this unresponsiveness, however, are completely unknown. The effects of steroids are largely mediated by the interference of the glucocorticoid receptor (GR) with proinflammatory transcription factors. In the present study, we therefore investigated the activation of the transcription factors nuclear factor‐κB (NF‐κB), activator protein‐1 (AP‐1), and the upstream kinases p38 and c‐Jun N‐terminal kinase (JNK) in steroid‐sensitive and steroid‐resistant patients with Crohn's disease. We demonstrated that steroid‐sensitive and steroid‐resistant patients reveal a remarkably different cellular activation pattern of these proinflammatory mediators. In steroid‐sensitive patients, activation of NF‐κB, AP‐1, p38, and JNK was mainly found in lamina propria macrophages. In contrast, steroid‐ resistant patients revealed activation of all these mediators mostly in epithelial cells. The functional interference of the proinflammatory mediators with the glucocorticoid response was supported by reporter gene assays. Expression of NF‐κB and, interestingly, also JNK1 and p38 inhibited the activity of the GR. Thus, our results suggest that steroid resistance is associated with increased epithelial activation of stress‐activated protein kinases and NF‐κB, which might inhibit the anti‐inflammatory action of a limited number of GRs.
[Robotic and systems technology for advanced endoscopic procedures].
2002-09-06

The advent of endoscopic techniques changed surgery in many regards. This paper intends to describe an overview about technologies to facilitate endoscopic surgery. The systems described have been developed for the use in general surgery, but an easy application also in other fields of endoscopic surgery seems realistic. The introduction of system technology and robotic technology enables today to design a highly ergonomic solo-surgery platform. This consists of a system of devices for endoscopic surgery (HF, light source, etc...) with which the surgeon interacts directly, positioning systems for optic and instruments that the surgeon drives as the likes without assistance, and a chair to increase the comfort of the surgeon during surgery. The system of endoscopic devices named OREST (Dornier, München) designed already in 1992 opened the way to a number of systems available today that allow to the surgeon a direct control of the instrumentation. A considerable step ahead in endoscopic technology is the introduction of robotic technology to design assisting systems for solo-surgery and microsurgical instrument manipulators. Results of a number of experimental trials on combinations of different positioning devices are presented and commented. A further step in the employment of robotic technology is the design of "master-slave manipulators" to provide the surgeon with additional degrees of freedom of instrumentation. In 1996 a first prototype of an endoscopic manipulator system, named ARTEMIS, designed in cooperation with the Research Center in Karlsruhe, could be used in experimental applications. Clinical use of the system, however, will require further development of the arm mechanics and the control system. The combination with the implementation of telecommunication technology will open new frontiers, such as teleconsulting, teleassistance and telemanipulation.
Proceedings of the Fourth Eurographics Workshop on Parallel Graphics and Visualization
2002-09-09

Welcome to the fourth Eurographics Workshop on Parallel Graphics and Visualization. It is held every second year in Europe, while our sister event, the IEEE Symposium on Parallel and Large-Data Visualization and Graphics takes place every other year in the USA. Together, we look into the state-of-the-art in parallel visual techniques. This year, we also had a special focus on large-data techniques which are not necessarily parallel.Several changes have taken place since the last time this event was held. Probably the most important change is that the proceedings are now published through ACM SIGGRAPH and will be available in the digital libraries of the ACM and of the Eurographics Association. This gives the contributions to our workshop a much better visibility than in the past years.This time, we received a total of 19 submissions of which we selected 14. Each of the papers was reviewed by at least three members of the international program committee. The number of accepted papers is larger than in previous years because we felt that there are more good submissions which deserve publication beyond the original planned paper limit. Additional to the 14 regular papers, there are two full papers from our invited speakers.
Effect of Heterogenic Surfaces on Contact Angle Hysteresis: Dynamic Contact Angle Analysis in Material Sciences
2002-09-10

Considerable economic damage is caused by biofilms on material surfaces originating when materials are in contact with aqueous biological systems. Therefore, (macro)molecular interfacial reactions at the interface between material surface and biological system are of basic interest for the development of advanced materials. Recently, the classic Wilhelmy balance method and the dynamic contact angle analysis have been successfully applied on initial interfacial reactions of surface-modified biomaterials.
Stem‐like cells in hepatoblastoma
2002-09-12

Abstract Background The principles of tumor biology suggest that hepatoblastoma is derived from a pluripotent stem cell. Our studies were undertaken to investigate this tumor for the presence of cells with morphologic and immunophenotypic features of the oval cells of rodents that are thought to be closely related to hepatic stem cells. Procedure Hepatoblastomas of various subtypes were investigated by electron microscopy and immunoelectron microscopy with antibodies against cytokeratin 7, in the liver a marker of biliary differentiation, and albumin, a marker of hepatocytic differentiation. Immunohistochemical investigations were performed with the antibodies OV‐1 and OV‐6, which recognize antigens associated with oval cells. Results OV‐1 stained scattered cells in seven of 12 tumors investigated and OV‐6 in nine. Small epithelial cells (SEC) with the ultrastructural features of the oval cells were found by electron microscopy. They were characterized by small size (7–18 μm), often an oval shape, tonofilament bundles, and tight junctions or desmosome‐like junctions. SEC were found in small numbers in areas of fetal differentiation and in moderate numbers in areas of embryonal differentiation. In small cell hepatoblastoma, nearly all the tumor cells exhibited SEC‐like features. Immunoelectron microscopy revealed coexpression of cytokeratin 7 and albumin by SEC. Conclusions SEC with ultrastructural and immunophenotypic features exhibited by oval cells, i.e., hepatic stem‐like cells, are found in hepatoblastoma. Their numbers vary with the differing degrees of differentiation seen in the various subtypes. The findings further support the hypothesis that hepatoblastoma is derived from a pluripotent stem cell. Med Pediatr Oncol 2002;39:504–507. © 2002 Wiley‐Liss, Inc.
The Neandertal type site revisited: Interdisciplinary investigations of skeletal remains from the Neander Valley, Germany
2002-09-13

The 1856 discovery of the Neandertal type specimen (Neandertal 1) in western Germany marked the beginning of human paleontology and initiated the longest-standing debate in the discipline: the role of Neandertals in human evolutionary history. We report excavations of cave sediments that were removed from the Feldhofer caves in 1856. These deposits have yielded over 60 human skeletal fragments, along with a large series of Paleolithic artifacts and faunal material. Our analysis of this material represents the first interdisciplinary analysis of Neandertal remains incorporating genetic, direct dating, and morphological dimensions simultaneously. Three of these skeletal fragments fit directly on Neandertal 1, whereas several others have distinctively Neandertal features. At least three individuals are represented in the skeletal sample. Radiocarbon dates for Neandertal 1, from which a mtDNA sequence was determined in 1997, and a second individual indicate an age of ≈40,000 yr for both. mtDNA analysis on the same second individual yields a sequence that clusters with other published Neandertal sequences.
Imidazole Inhibitors of Cytokine Release:  Probing Substituents in the 2 Position
2002-09-13

Novel 2,4,5-trisubstituted imidazole derivatives were prepared as potential anticytokine agents. Thirty-seven compounds were tested on their ability to inhibit the release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) from peripheral blood mononuclear cells (PBMC) or human whole blood. SARs (structure activity relationships) for substituents at the 4 and 5 position of the imidazole core were similar to those described for other inhibitors of cytokine release and p38 MAP (mitogen-activated protein) kinase. Starting from benzylsulfanyl imidazole 2b (IC(50) p38, 4.0 microM; TNF-alpha, 1.1 microM; IL-1beta, 0.38 microM), the contribution of substituents at the 2 position to enzyme inhibitory and cellular activity of test compounds was investigated. This strategy led to the identification of compound 2q (IC(50) p38, 0.63 microM; TNF-alpha, 0.90 microM; IL-1beta, 0.04 microM), which was 6-10 times more potent than the initial lead 2b with respect to inhibition of p38 and IL-1beta release and equipotently inhibited TNF-alpha release.
Sirolimus-Eluting Stents for the Treatment of Obstructive Superficial Femoral Artery Disease
2002-09-16

Background— Stent implantation for obstructive femoropopliteal artery disease has been associated with poor long-term outcomes. This study evaluated the effectiveness of shape memory alloy recoverable technology (SMART) nitinol self-expanding stents coated with a polymer impregnated with sirolimus (rapamycin) versus uncoated SMART stents in superficial femoral artery obstructions. Methods and Results— Thirty-six patients were recruited for this double-blind, randomized, prospective trial. All patients had chronic limb ischemia and femoral artery occlusions (57%) or stenoses (average lesion length, 85±57 mm). Patients were eligible for randomization after successful guidewire passage across the lesion. Eighteen patients received sirolimus-eluting SMART stents and 18 patients received uncoated SMART stents. The primary end point of the study was the in-stent mean percent diameter stenosis, as measured by quantitative angiography at 6 months. The in-stent mean percent diameter stenosis was 22.6% in the sirolimus-eluting stent group versus 30.9% in the uncoated stent group ( P =0.294). The in-stent mean lumen diameter was significantly larger in the sirolimus-eluting stent group (4.95 mm versus 4.31 mm in the uncoated stent group; P =0.047). No serious adverse events (death or prolonged hospitalization) were reported. Conclusions— The use of sirolimus-eluting SMART stents for superficial femoral artery occlusion is feasible, with a trend toward reducing late loss compared with uncoated stents. The coated stent also proved to be safe and was not associated with any serious adverse events.
Fluorobalhimycin—A New Chapter in Glycopeptide Antibiotic Research
2002-09-16

Mutasynthesis—a very potent tool? The two chlorine atoms attached to the aglycon of vancomycin-type glycopeptide antibiotics (see structure) have considerable influence on the antibiotic activity of each compound. By combining molecular genetic methods and chemical synthesis these chlorine atoms can be replaced by fluorine atoms. The described approach may also be applicable to modifying other parts of the glycopeptide molecule.