Effect of various antithrombotic regimens (aspirin, aspirin plus dipyridamole, anticoagulants) on the functional status of patients and grafts one year after coronary artery bypass grafting

From 1987 until 1991 a large prospective randomized multicentre study was performed in The Netherlands, Germany and Switzerland entitled CABADAS (Prevention of Coronary Artery Bypass graft occlusion by Aspirin, Dipyridamole, and Acenocoumarol/Phenprocoumon Study). The aim of CABADAS was to evaluate the relative efficacy of (1) aspirin, (2) aspirin plus dipyridamole, and (3) oral anticoagulants in the prevention of vein graft occlusion during the first year after aortocoronary bypass surgery. No significant difference was observed in the incidence of graft occlusion among the three treatment groups. In a subgroup of 127 CABADAS patients, studied in the Academic Medical Centre in Amsterdam, the relationship between treatment and clinical status (i.e. symptoms of angina pectoris and exercise capacity) was assessed, and the relationship between treatment and functional status of the vein grafts was determined by means of thallium-201 exercise scintigraphy. There were no differences in symptoms among the three treatment groups in the 127 patients studied. There were no significant differences either among the treatment groups, as regards exercise capacity and the number or intensity of perfusion defects, in the 81 patients who underwent thallium-201 exercise scintigraphy. The three antithrombotic treatment regimens had a similar effect on the clinical status of patients and on the functional status of venous bypass grafts one year after coronary bypass surgery. This finding underscores the CABADAS results in that aspirin may be the preferred treatment option in patients following venous bypass surgery.     

Texture Characterization of High-Temperature Superconductor Wires

Texture measurements have been made for BSCCO tapes produced by dip coating and by powder-in-tube techniques. The texture of the Bi2212 grains was characterized for both c axis texture using (001) pole figures from 008 reflections and a–b axis texture using (115) pole figures. The critical current densities of these tapes were also measured and correlated with texture parameters obtained from contours of the pole figures. For the tapes with good current transport, the arrangement of grains in a crystallographic sense was inferred from the pole figures and was found to be consistent with a model based on global alignment of the c axes and the presence of colonies of grains differing mostly in c axis twist.     

Avoiding adverse drug effects in elderly patients

This review delineates why commonly prescribed drugs and dosages often have unexpected responses in the elderly, and suggests ways to improve prescribing for this vulnerable population.     

The roles of perforin- and Fas-dependent cytotoxicity in protection against cytopathic and noncytopathic viruses

In vitro, T cell-dependent cytotoxicity is mediated by two distinct mechanisms, one being perforin-, the other Fas-dependent. The contribution of both of these mechanisms to clearance of viral infections was investigated in mice for the non-cytopathic lymphocytic choriomeningitis virus (LCMV) and the cytopathic vaccinia, vesicular stomatitis (VSV) and Semliki forest (SFV) viruses. Clearance of an acute LCMV infection was mediated by the perforin-dependent mechanism without measurable involvement of the Fas-dependent pathway. For the resolution of vaccinia virus infection and for resistance against VSV and SFV, however, neither of the two pathways was required. These data suggest that perforin-dependent cytotoxicity mediated by T cells is crucial for protection against non-cytopathic viruses, whereas infections with cytopathic viruses are controlled by nonlytic T cell-dependent soluble mediators such as cytokines (IFN-gamma against vaccinia virus) and neutralizing antibodies (against VSV and SFV).     

Properties,implementations and applications of rank filters

The results of research on rank filters are presented. The relationship of rank filters with other filters is briefly discussed. The main properties of rank filters are listed and an explanation is given for these properties. Several software and hardware implementations of the filter are described. Major applications to image processing are discussed, including noise smoothing, cluster detection, skeletization, edge enhancement and edge detection.     

Color indicator of cuprate superconductivity observed by polarized light microscopy

A common mineralogical technique for identifying individual crystals in a heterogeneous, polycrystalline sample involves the observation at room temperature of their colors in reflected polarized light (colors of polarization). Here we present the observation that a brownish yellow (golden) color of polarization is not only characteristic of the YBa₂Cu₃O₇ superconductor, but of the cuprate superconductors in general and is correlated with the occurrence of superconductivity.